/* ============================================================
   VAB-CODE (vab-code) — Premium Dark-Mode Online IDE
   Inspired by Linear, Vercel Dashboard, VS Code
   ============================================================ */

/* ---------- Reset & Base ---------- */
*, *::before, *::after {
  box-sizing: border-box;
  margin: 0;
  padding: 0;
}

:root {
  --bg-deep:    #06070a;
  --bg-base:    #0a0c12;
  --bg-surface: #0f1119;
  --bg-raised:  #151821;
  --bg-hover:   #1a1e2b;
  --bg-active:  #1f2435;

  --border:       rgba(255,255,255,0.07);
  --border-hover: rgba(255,255,255,0.12);
  --border-focus: rgba(129,140,248,0.5);

  --text-primary:   #e8ecf4;
  --text-secondary: #8b93a7;
  --text-muted:     #4b5268;

  --accent:         #818cf8;
  --accent-bright:  #a78bfa;
  --green:          #34d399;
  --red:            #f87171;
  --amber:          #fbbf24;
  --cyan:           #22d3ee;

  --font-sans: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', system-ui, sans-serif;
  --font-mono: 'JetBrains Mono', 'Fira Code', 'Cascadia Code', monospace;

  --header-h: 54px;
  --langbar-h: 86px;
  --radius: 10px;
  --radius-lg: 14px;
}

html, body {
  min-height: 100%;
  overflow-x: hidden;
  overflow-y: auto;
  font-family: var(--font-sans);
  background: var(--bg-deep);
  color: var(--text-primary);
  -webkit-font-smoothing: antialiased;
}

::selection {
  background: rgba(129,140,248,0.3);
  color: #fff;
}

/* Scrollbars */
::-webkit-scrollbar { width: 6px; height: 6px; }
::-webkit-scrollbar-track { background: transparent; }
::-webkit-scrollbar-thumb { background: rgba(255,255,255,0.1); border-radius: 99px; }
::-webkit-scrollbar-thumb:hover { background: rgba(255,255,255,0.2); }


/* ---------- HEADER ---------- */
.header {
  height: var(--header-h);
  background: var(--bg-surface);
  border-bottom: 1px solid var(--border);
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 0 20px;
  position: relative;
  z-index: 20;
}

.header-left, .header-right { display: flex; align-items: center; gap: 12px; }
.header-center { display: flex; align-items: center; }

/* Logo */
.logo { display: flex; align-items: center; gap: 10px; }
.logo-icon {
  width: 32px; height: 32px;
  border-radius: 8px;
  background: var(--bg-raised);
  border: 1px solid var(--border);
  display: grid; place-items: center;
  box-shadow: 0 1px 3px rgba(0, 0, 0, 0.3);
}
.logo-text {
  font-weight: 800;
  font-size: 16px;
  letter-spacing: -0.3px;
  background: linear-gradient(135deg, #e0e7ff, #c4b5fd);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
}
.logo-badge {
  display: block;
  font-size: 9px;
  font-weight: 700;
  letter-spacing: 0.1em;
  color: var(--text-muted);
  margin-top: -2px;
}

/* Nav Tabs */
.nav-tabs { display: flex; gap: 4px; }
.nav-tab {
  display: flex; align-items: center; gap: 6px;
  padding: 7px 16px;
  border-radius: 8px;
  border: none;
  background: transparent;
  color: var(--text-secondary);
  font: 500 13px var(--font-sans);
  cursor: pointer;
  transition: all 0.15s;
}
.nav-tab:hover { background: var(--bg-hover); color: var(--text-primary); }
.nav-tab.active {
  background: var(--accent);
  color: #fff;
  box-shadow: 0 2px 12px -2px rgba(129,140,248,0.4);
}

/* Runtime Badge */
.runtime-badge {
  display: flex; align-items: center; gap: 7px;
  padding: 5px 12px;
  border-radius: 8px;
  background: rgba(52,211,153,0.08);
  border: 1px solid rgba(52,211,153,0.2);
  font: 500 11px var(--font-mono);
  color: var(--green);
}
.pulse-dot {
  width: 6px; height: 6px;
  border-radius: 50%;
  background: var(--green);
  animation: pulse 2s ease-in-out infinite;
}
@keyframes pulse {
  0%, 100% { opacity: 1; transform: scale(1); }
  50% { opacity: 0.5; transform: scale(0.8); }
}


/* ---------- WORKSPACE ---------- */
.workspace {
  height: calc(100vh - var(--header-h));
  display: flex;
  flex-direction: column;
}

/* ---------- LANGUAGE BAR (COMPACT & PRO) ---------- */
.lang-bar {
  background: var(--bg-base);
  border-bottom: 1px solid var(--border);
  padding: 0 12px;
  flex-shrink: 0;
}

.lang-bar-inner {
  display: flex;
  align-items: center;
  gap: 10px;
  padding: 6px 0;
  border-bottom: 1px solid var(--border);
}

.lang-bar-label {
  font: 600 10.5px var(--font-sans);
  text-transform: uppercase;
  letter-spacing: 0.06em;
  color: var(--text-muted);
  white-space: nowrap;
}

.lang-buttons { display: flex; gap: 4px; flex-wrap: wrap; }

.lang-divider {
  width: 1px;
  height: 20px;
  background: var(--border);
  margin: 0 2px;
}

.lang-btn {
  display: flex; align-items: center; gap: 5px;
  padding: 4px 10px;
  border-radius: 6px;
  border: 1px solid transparent;
  background: transparent;
  color: var(--text-secondary);
  font: 500 11.5px var(--font-sans);
  cursor: pointer;
  transition: all 0.15s;
}
.lang-btn:hover {
  background: var(--bg-hover);
  border-color: var(--border-hover);
  color: var(--text-primary);
}
.lang-btn.active {
  background: var(--bg-active);
  border-color: var(--border-focus);
  color: #fff;
  box-shadow: 0 0 10px -3px rgba(129,140,248,0.3);
}
.lang-dot {
  width: 7px; height: 7px;
  border-radius: 50%;
  flex-shrink: 0;
}

/* Editor Toolbar */
.editor-toolbar {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 6px 0;
  gap: 8px;
  flex-wrap: wrap;
}

.file-name {
  font: 500 12px var(--font-mono);
  color: var(--text-secondary);
  padding: 4px 10px;
  border-radius: 6px;
  background: var(--bg-raised);
  border: 1px solid var(--border);
  white-space: nowrap;
}

.toolbar-divider {
  width: 1px;
  height: 22px;
  background: var(--border);
  margin: 0 2px;
  flex-shrink: 0;
}

.toolbar-actions {
  display: flex;
  align-items: center;
  gap: 6px;
  flex-wrap: wrap;
}

.icon-btn {
  display: grid; place-items: center;
  width: 32px; height: 32px;
  border-radius: 8px;
  border: 1px solid var(--border);
  background: transparent;
  color: var(--text-secondary);
  cursor: pointer;
  transition: all 0.15s;
}
.icon-btn:hover {
  background: var(--bg-hover);
  color: var(--text-primary);
  border-color: var(--border-hover);
}
.icon-btn.small { width: 28px; height: 28px; border: none; }

.save-code-btn {
  display: flex;
  align-items: center;
  gap: 6px;
  padding: 5px 12px;
  border-radius: 8px;
  border: 1px solid rgba(56, 189, 248, 0.35);
  background: rgba(56, 189, 248, 0.08);
  color: #e0f2fe;
  font: 600 12px var(--font-sans);
  cursor: pointer;
  transition: all 0.15s;
}
.save-code-btn:hover {
  background: rgba(56, 189, 248, 0.18);
  border-color: rgba(56, 189, 248, 0.6);
  box-shadow: 0 0 14px -2px rgba(56, 189, 248, 0.35);
  transform: translateY(-1px);
}
.save-code-btn:active {
  transform: scale(0.97);
}

/* Core Lab Auto-Translator Badge */
.core-lang-badge {
  margin-left: auto;
  display: flex;
  align-items: center;
  gap: 6px;
  padding: 4px 10px;
  border-radius: 6px;
  background: rgba(167,139,250,0.08);
  border: 1px solid rgba(167,139,250,0.22);
  font: 500 11px var(--font-mono);
  color: #c4b5fd;
  white-space: nowrap;
}

/* Cross-Translate Toolbar Button & Dropdown */
.translate-dropdown-wrapper {
  position: relative;
  display: inline-block;
}

.translate-btn {
  display: flex;
  align-items: center;
  gap: 6px;
  padding: 5px 12px;
  border-radius: 8px;
  border: 1px solid rgba(167,139,250,0.3);
  background: rgba(167,139,250,0.08);
  color: #e0e7ff;
  font: 600 12px var(--font-sans);
  cursor: pointer;
  transition: all 0.2s;
}

.translate-btn:hover {
  background: rgba(167,139,250,0.18);
  border-color: rgba(167,139,250,0.5);
  box-shadow: 0 0 14px -3px rgba(167,139,250,0.35);
  transform: translateY(-1px);
}

.translate-btn:active {
  transform: scale(0.97);
}

.translate-btn.disabled {
  opacity: 0.35;
  cursor: not-allowed;
  pointer-events: none;
  border-color: var(--border);
  background: transparent;
  color: var(--text-muted);
}

.translate-menu {
  position: absolute;
  top: calc(100% + 6px);
  left: 0;
  z-index: 45;
  min-width: 220px;
  background: var(--bg-surface);
  border: 1px solid var(--border-hover);
  border-radius: var(--radius);
  box-shadow: 0 16px 36px rgba(0,0,0,0.7), 0 0 20px rgba(129,140,248,0.15);
  padding: 6px;
  backdrop-filter: blur(12px);
  animation: toastIn 0.15s forwards;
}

.translate-menu-header {
  display: flex;
  align-items: center;
  gap: 6px;
  font: 600 10px var(--font-mono);
  text-transform: uppercase;
  letter-spacing: 0.05em;
  color: var(--text-muted);
  padding: 6px 8px 4px 8px;
}

.translate-menu-list {
  display: flex;
  flex-direction: column;
  gap: 2px;
}

.translate-menu-item {
  display: flex;
  align-items: center;
  gap: 8px;
  width: 100%;
  padding: 8px 10px;
  border-radius: 6px;
  border: none;
  background: transparent;
  color: var(--text-primary);
  font: 500 12px var(--font-sans);
  cursor: pointer;
  transition: all 0.15s;
  text-align: left;
}

.translate-menu-item:hover {
  background: var(--bg-hover);
  color: #fff;
}

.translate-menu-footer {
  padding: 6px 8px 2px 8px;
  font: 500 9px var(--font-mono);
  color: var(--text-muted);
  border-top: 1px solid var(--border);
  margin-top: 4px;
}

/* High-Contrast Translation Loading Overlay */
.translation-overlay {
  position: absolute;
  inset: 0;
  z-index: 35;
  background: rgba(6, 7, 10, 0.88);
  backdrop-filter: blur(12px);
  display: flex;
  align-items: center;
  justify-content: center;
  padding: 20px;
  animation: overlayFadeIn 0.2s ease-out;
}

@keyframes overlayFadeIn {
  from { opacity: 0; transform: scale(0.98); }
  to { opacity: 1; transform: scale(1); }
}

.translation-card {
  position: relative;
  max-width: 440px;
  width: 100%;
  background: linear-gradient(180deg, #151824 0%, #0d0f17 100%);
  border: 1px solid rgba(167, 139, 250, 0.35);
  border-radius: 16px;
  padding: 28px 24px;
  text-align: center;
  box-shadow: 0 25px 60px -10px rgba(0,0,0,0.85), 0 0 40px rgba(129, 140, 248, 0.25);
  overflow: hidden;
}

.translation-glow {
  position: absolute;
  top: -50px;
  left: 50%;
  transform: translateX(-50%);
  width: 220px;
  height: 120px;
  background: radial-gradient(circle, rgba(167,139,250,0.3) 0%, transparent 70%);
  pointer-events: none;
}

.translation-badge-row {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  padding: 3px 10px;
  border-radius: 99px;
  background: rgba(52,211,153,0.1);
  border: 1px solid rgba(52,211,153,0.25);
  font: 500 10px var(--font-mono);
  color: var(--green);
  margin-bottom: 12px;
}

.translation-icon-wrapper {
  position: relative;
  width: 64px;
  height: 64px;
  margin: 8px auto 16px;
  display: grid;
  place-items: center;
}

.translation-spin-ring {
  position: absolute;
  inset: 0;
  border: 2.5px solid transparent;
  border-top-color: #facc15;
  border-right-color: #a78bfa;
  border-radius: 50%;
  animation: spinRing 1s linear infinite;
}

@keyframes spinRing {
  to { transform: rotate(360deg); }
}

.translation-bolt-icon {
  width: 28px;
  height: 28px;
  color: #facc15;
  filter: drop-shadow(0 0 12px rgba(250,204,21,0.7));
  animation: boltPulse 1.2s ease-in-out infinite;
}

@keyframes boltPulse {
  0%, 100% { transform: scale(1); filter: drop-shadow(0 0 8px rgba(250,204,21,0.5)); }
  50% { transform: scale(1.15); filter: drop-shadow(0 0 16px rgba(250,204,21,0.9)); }
}

.translation-title {
  font: 700 17px var(--font-sans);
  color: #fff;
  margin-bottom: 6px;
  letter-spacing: -0.2px;
}

.translation-desc {
  font: 400 12px var(--font-sans);
  color: var(--text-secondary);
  line-height: 1.5;
  margin-bottom: 16px;
}

.translation-meter {
  height: 4px;
  border-radius: 99px;
  background: rgba(255,255,255,0.08);
  overflow: hidden;
  margin-bottom: 14px;
  position: relative;
}

.translation-meter-bar {
  height: 100%;
  width: 50%;
  background: linear-gradient(90deg, #facc15, #a78bfa, #38bdf8);
  border-radius: 99px;
  animation: meterSlide 1.2s ease-in-out infinite;
}

@keyframes meterSlide {
  0% { transform: translateX(-100%); }
  50% { transform: translateX(50%); }
  100% { transform: translateX(200%); }
}

.translation-foot {
  font: 500 10px var(--font-mono);
  color: var(--text-muted);
  letter-spacing: 0.02em;
}

/* Translation Success / Revert Banner */
.translation-banner {
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  z-index: 25;
  background: linear-gradient(90deg, rgba(30,27,75,0.95), rgba(15,23,42,0.95));
  border-bottom: 1px solid rgba(167,139,250,0.3);
  padding: 8px 16px;
  display: flex;
  align-items: center;
  justify-content: space-between;
  backdrop-filter: blur(8px);
  animation: bannerSlideDown 0.2s ease-out;
}

@keyframes bannerSlideDown {
  from { transform: translateY(-100%); opacity: 0; }
  to { transform: translateY(0); opacity: 1; }
}

.banner-content {
  display: flex;
  align-items: center;
  gap: 10px;
}

.banner-badge {
  display: flex;
  align-items: center;
  gap: 4px;
  padding: 2px 7px;
  border-radius: 4px;
  background: rgba(250,204,21,0.15);
  border: 1px solid rgba(250,204,21,0.3);
  font: 700 9px var(--font-mono);
  color: #fde047;
  letter-spacing: 0.05em;
}

.banner-text {
  font: 500 12px var(--font-sans);
  color: var(--text-primary);
}

.banner-actions {
  display: flex;
  align-items: center;
  gap: 8px;
}

.banner-btn.revert {
  display: flex;
  align-items: center;
  gap: 5px;
  padding: 4px 10px;
  border-radius: 6px;
  border: 1px solid rgba(255,255,255,0.12);
  background: rgba(255,255,255,0.06);
  color: var(--text-primary);
  font: 500 11px var(--font-sans);
  cursor: pointer;
  transition: all 0.15s;
}

.banner-btn.revert:hover {
  background: rgba(255,255,255,0.12);
  border-color: rgba(255,255,255,0.25);
  color: #fff;
}

.banner-close {
  width: 22px;
  height: 22px;
  display: grid;
  place-items: center;
  border: none;
  background: transparent;
  color: var(--text-muted);
  cursor: pointer;
  border-radius: 4px;
  transition: all 0.15s;
}

.banner-close:hover {
  color: var(--text-primary);
  background: rgba(255,255,255,0.08);
}

/* Run Button */
.run-btn {
  display: inline-flex; align-items: center; gap: 8px;
  padding: 6px 16px;
  border-radius: 8px;
  border: none;
  background: linear-gradient(135deg, #059669, #10b981);
  color: #fff;
  font: 700 13px var(--font-sans);
  cursor: pointer;
  transition: all 0.2s;
  box-shadow: 0 4px 16px -4px rgba(16,185,129,0.5);
  flex-shrink: 0;
  white-space: nowrap;
}
.run-btn:hover {
  background: linear-gradient(135deg, #047857, #059669);
  transform: translateY(-1px);
  box-shadow: 0 6px 20px -4px rgba(16,185,129,0.5);
}
.run-btn:active { transform: scale(0.97); }

.run-btn.running {
  background: linear-gradient(135deg, #b45309, #d97706);
  box-shadow: 0 4px 16px -4px rgba(217,119,6,0.4);
  pointer-events: none;
}

.run-shortcut {
  font: 500 10px var(--font-mono);
  opacity: 0.6;
  padding: 2px 6px;
  border-radius: 4px;
  background: rgba(255,255,255,0.12);
}


/* ---------- EDITOR + OUTPUT SPLIT ---------- */
.editor-output-split {
  flex: 1;
  display: flex;
  flex-direction: column;
  min-height: 0;
}

/* Editor Panel */
.editor-panel {
  flex: 1;
  min-height: 120px;
  position: relative;
  background: var(--bg-deep);
}

/* Code Editor Wrapper (Left Side from Top to Bottom) */
.code-editor-wrapper {
  position: absolute;
  inset: 0;
  display: flex;
  width: 100%;
  height: 100%;
  background: #080a12;
  overflow: hidden;
  z-index: 5;
}

.editor-gutter {
  width: 52px;
  background: #05070d;
  border-right: 1px solid rgba(255, 255, 255, 0.08);
  color: #64748b;
  font-family: var(--font-mono);
  font-size: 13px;
  line-height: 22px;
  padding: 14px 10px 14px 6px;
  text-align: right;
  user-select: none;
  overflow: hidden;
  white-space: pre;
  flex-shrink: 0;
}

.fallback-editor {
  flex: 1;
  height: 100%;
  background: transparent;
  color: #f1f5f9;
  font-family: var(--font-mono);
  font-size: 13.5px;
  line-height: 22px;
  padding: 14px 16px;
  border: none;
  outline: none;
  resize: none;
  tab-size: 4;
  white-space: pre;
  overflow: auto;
  caret-color: #38bdf8;
  word-wrap: normal;
}

/* Split Handle */
.split-handle {
  height: 6px;
  background: var(--bg-surface);
  cursor: row-resize;
  display: grid;
  place-items: center;
  transition: background 0.15s;
  position: relative;
  z-index: 5;
}
.split-handle:hover, .split-handle.dragging { background: var(--accent); }
.handle-grip {
  width: 40px;
  height: 2px;
  border-radius: 2px;
  background: rgba(255,255,255,0.15);
}

/* Output Panel */
.output-panel {
  height: 260px;
  min-height: 100px;
  display: flex;
  flex-direction: column;
  background: var(--bg-deep);
  border-top: 1px solid var(--border);
}

/* Output Tabs */
.output-tabs {
  display: flex;
  align-items: center;
  gap: 2px;
  padding: 4px 12px;
  background: var(--bg-surface);
  border-bottom: 1px solid var(--border);
}

.output-tab {
  display: flex; align-items: center; gap: 6px;
  padding: 6px 14px;
  border-radius: 6px;
  border: none;
  background: transparent;
  color: var(--text-muted);
  font: 500 12px var(--font-sans);
  cursor: pointer;
  transition: all 0.15s;
}
.output-tab:hover { color: var(--text-secondary); }
.output-tab.active {
  background: var(--bg-raised);
  color: var(--text-primary);
  border: 1px solid var(--border);
}

/* Console */
.console-output {
  flex: 1;
  overflow-y: auto;
  padding: 14px 18px;
  font: 13px/1.7 var(--font-mono);
}

.console-line { word-break: break-word; }
.console-line.stdout { color: var(--text-primary); }
.console-line.stderr { color: var(--red); }
.console-line.info   { color: var(--cyan); }
.console-line.success { color: var(--green); }
.console-line.warn   { color: var(--amber); }
.console-line.system { color: var(--accent-bright); }
.console-line.dim    { color: var(--text-muted); }

/* Blinking cursor at the end of output */
.cursor-blink {
  display: inline-block;
  width: 7px; height: 15px;
  background: var(--accent);
  vertical-align: text-bottom;
  animation: blink 1s step-end infinite;
}
@keyframes blink {
  0%, 100% { opacity: 1; }
  50% { opacity: 0; }
}

/* Web Preview */
.web-preview {
  flex: 1;
  background: #fff;
}
.web-preview iframe {
  width: 100%;
  height: 100%;
  border: none;
}

/* Status Bar */
.status-bar {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 0 14px;
  height: 26px;
  background: var(--bg-surface);
  border-top: 1px solid var(--border);
  font: 500 11px var(--font-mono);
  color: var(--text-muted);
}
.status-left, .status-right { display: flex; align-items: center; gap: 14px; }

.status-indicator { display: flex; align-items: center; gap: 6px; }
.status-dot {
  width: 6px; height: 6px; border-radius: 50%;
}
.status-dot.green { background: var(--green); }
.status-dot.amber { background: var(--amber); }
.status-dot.red   { background: var(--red); }


/* ---------- PROBLEMS OVERLAY ---------- */
.overlay {
  position: fixed;
  inset: 0;
  z-index: 50;
  background: rgba(0,0,0,0.7);
  backdrop-filter: blur(8px);
  display: grid;
  place-items: center;
  padding: 20px;
}

.overlay-content {
  background: var(--bg-surface);
  border: 1px solid var(--border);
  border-radius: var(--radius-lg);
  width: 100%;
  max-width: 700px;
  max-height: 80vh;
  display: flex;
  flex-direction: column;
  box-shadow: 0 32px 64px -16px rgba(0,0,0,0.6);
}

.overlay-header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 20px 24px;
  border-bottom: 1px solid var(--border);
}
.overlay-header h2 {
  font: 700 18px var(--font-sans);
  color: var(--text-primary);
}
.overlay-header p {
  font: 400 12px var(--font-sans);
  color: var(--text-secondary);
  margin-top: 2px;
}

.problems-list {
  flex: 1;
  overflow-y: auto;
  padding: 16px;
  display: flex;
  flex-direction: column;
  gap: 10px;
}

.problem-card {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 16px 18px;
  border-radius: var(--radius);
  background: var(--bg-raised);
  border: 1px solid var(--border);
  cursor: pointer;
  transition: all 0.15s;
}
.problem-card:hover {
  border-color: var(--border-focus);
  background: var(--bg-active);
}
.problem-card .title {
  font: 600 14px var(--font-sans);
  color: var(--text-primary);
}
.problem-card .meta {
  display: flex; gap: 8px; margin-top: 4px;
}
.problem-card .tag {
  font: 500 10px var(--font-mono);
  padding: 2px 8px;
  border-radius: 4px;
  background: var(--bg-base);
  color: var(--text-muted);
}
.problem-card .difficulty {
  font: 700 11px var(--font-sans);
  padding: 3px 10px;
  border-radius: 6px;
  background: rgba(52,211,153,0.1);
  color: var(--green);
  border: 1px solid rgba(52,211,153,0.2);
  align-self: center;
}
.problem-card .difficulty.medium {
  background: rgba(251,191,36,0.1);
  color: var(--amber);
  border-color: rgba(251,191,36,0.2);
}


/* ---------- TOAST ---------- */
.toast-container {
  position: fixed;
  bottom: 20px;
  right: 20px;
  z-index: 100;
  display: flex;
  flex-direction: column;
  gap: 8px;
  pointer-events: none;
}

.toast {
  pointer-events: auto;
  padding: 10px 18px;
  border-radius: var(--radius);
  background: var(--bg-raised);
  border: 1px solid var(--border);
  color: var(--text-primary);
  font: 500 12px var(--font-sans);
  box-shadow: 0 12px 32px -8px rgba(0,0,0,0.5);
  transform: translateY(10px);
  opacity: 0;
  animation: toastIn 0.25s forwards;
}
.toast.success { border-color: rgba(52,211,153,0.3); }
.toast.error   { border-color: rgba(248,113,113,0.3); }

@keyframes toastIn {
  to { opacity: 1; transform: translateY(0); }
}
@keyframes toastOut {
  to { opacity: 0; transform: translateY(10px); }
}


/* ============================================================
   NEW FEATURES & FIXES:
   1. Compiler Lazy Loading Init Overlay (Problem 1 Fix)
   2. Lab Manual & Guides (Problem 3 AdSense Fix)
   3. Saved Code History & Warning Banner (Problem 4 Storage Fix)
   4. Cloud Sync Upgrade Modal
   ============================================================ */

/* Header Saved Code Button */
.header-action-btn {
  display: flex;
  align-items: center;
  gap: 7px;
  padding: 6px 12px;
  border-radius: 8px;
  border: 1px solid var(--border);
  background: var(--bg-raised);
  color: var(--text-primary);
  font: 500 12px var(--font-sans);
  cursor: pointer;
  transition: all 0.15s;
}
.header-action-btn:hover {
  background: var(--bg-hover);
  border-color: var(--border-hover);
  color: #fff;
}
.history-badge {
  font: 700 10px var(--font-mono);
  padding: 1px 6px;
  border-radius: 99px;
  background: rgba(167,139,250,0.18);
  color: #c4b5fd;
  border: 1px solid rgba(167,139,250,0.3);
}

.badge-mini-accent {
  font: 700 9px var(--font-mono);
  padding: 2px 7px;
  border-radius: 4px;
  background: rgba(129,140,248,0.15);
  color: #a78bfa;
  border: 1px solid rgba(129,140,248,0.3);
  text-transform: uppercase;
  letter-spacing: 0.05em;
}
.badge-mini-green {
  font: 700 9px var(--font-mono);
  padding: 2px 7px;
  border-radius: 4px;
  background: rgba(52,211,153,0.15);
  color: #34d399;
  border: 1px solid rgba(52,211,153,0.3);
  text-transform: uppercase;
  letter-spacing: 0.05em;
}

/* ──── 1. Compiler Lazy Loading Init Overlay ──── */
.compiler-init-overlay {
  position: fixed;
  inset: 0;
  z-index: 90;
  background: rgba(4, 5, 8, 0.92);
  backdrop-filter: blur(14px);
  display: flex;
  align-items: center;
  justify-content: center;
  padding: 20px;
  animation: overlayFadeIn 0.25s ease-out;
}

.compiler-init-card {
  position: relative;
  max-width: 500px;
  width: 100%;
  background: linear-gradient(180deg, #151824 0%, #0b0d14 100%);
  border: 1px solid rgba(129, 140, 248, 0.35);
  border-radius: 20px;
  padding: 32px 28px;
  text-align: center;
  box-shadow: 0 30px 70px -10px rgba(0,0,0,0.9), 0 0 50px rgba(129, 140, 248, 0.2);
  overflow: hidden;
}

.init-glow {
  position: absolute;
  top: -60px;
  left: 50%;
  transform: translateX(-50%);
  width: 260px;
  height: 140px;
  background: radial-gradient(circle, rgba(129,140,248,0.3) 0%, transparent 70%);
  pointer-events: none;
}

.init-icon-wrapper {
  position: relative;
  width: 68px;
  height: 68px;
  margin: 0 auto 16px;
  display: grid;
  place-items: center;
}

.init-spin-ring {
  position: absolute;
  inset: 0;
  border: 3px solid transparent;
  border-top-color: #818cf8;
  border-right-color: #34d399;
  border-radius: 50%;
  animation: spinRing 1.1s linear infinite;
}

.init-icon {
  width: 32px;
  height: 32px;
  color: #a78bfa;
  filter: drop-shadow(0 0 10px rgba(167,139,250,0.6));
}

.init-title {
  font: 700 18px var(--font-sans);
  color: #fff;
  margin-bottom: 6px;
  letter-spacing: -0.2px;
}

.init-subtitle {
  font: 400 12px var(--font-sans);
  color: var(--text-secondary);
  margin-bottom: 20px;
  line-height: 1.5;
}

.init-progress-bar {
  height: 6px;
  border-radius: 99px;
  background: rgba(255,255,255,0.08);
  overflow: hidden;
  margin-bottom: 20px;
}

.init-progress-fill {
  height: 100%;
  width: 15%;
  background: linear-gradient(90deg, #818cf8, #a78bfa, #34d399);
  border-radius: 99px;
  transition: width 0.3s ease;
}

.init-step-list {
  display: flex;
  flex-direction: column;
  gap: 10px;
  text-align: left;
  background: rgba(0,0,0,0.3);
  padding: 14px 16px;
  border-radius: 12px;
  border: 1px solid var(--border);
  margin-bottom: 20px;
}

.init-step {
  display: flex;
  align-items: center;
  gap: 10px;
  font: 500 12px var(--font-sans);
  color: var(--text-muted);
}
.init-step.done { color: var(--green); }
.init-step.done .step-icon { color: var(--green); font-weight: 700; }
.init-step.active { color: #fff; font-weight: 600; }
.init-step.active .step-icon { color: #facc15; }

.init-footer {
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 8px;
  font: 500 11px var(--font-mono);
  color: var(--text-muted);
}


/* ──── 2. Lab Manual & Guides (Problem 3 Fix) ──── */
.guides-modal-content {
  max-width: 960px;
  width: 95vw;
  max-height: 88vh;
}

.guides-toolbar {
  padding: 12px 20px;
  border-bottom: 1px solid var(--border);
  display: flex;
  flex-direction: column;
  gap: 10px;
  background: var(--bg-base);
}

.guides-search-box {
  display: flex;
  align-items: center;
  gap: 8px;
  padding: 8px 12px;
  border-radius: 8px;
  background: var(--bg-surface);
  border: 1px solid var(--border);
}
.guides-search-box input {
  flex: 1;
  background: transparent;
  border: none;
  color: var(--text-primary);
  font: 400 13px var(--font-sans);
  outline: none;
}

.guides-filter-chips {
  display: flex;
  gap: 6px;
  flex-wrap: wrap;
}

.filter-chip {
  padding: 4px 12px;
  border-radius: 6px;
  border: 1px solid var(--border);
  background: var(--bg-raised);
  color: var(--text-secondary);
  font: 500 11px var(--font-sans);
  cursor: pointer;
  transition: all 0.15s;
}
.filter-chip:hover {
  background: var(--bg-hover);
  color: var(--text-primary);
}
.filter-chip.active {
  background: var(--accent);
  color: #fff;
  border-color: var(--accent);
}

.guides-list {
  flex: 1;
  overflow-y: auto;
  padding: 18px 20px;
  display: flex;
  flex-direction: column;
  gap: 16px;
}

.guide-article-card {
  background: var(--bg-raised);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 20px;
  transition: all 0.2s;
  display: flex;
  flex-direction: column;
  gap: 12px;
}
.guide-article-card:hover {
  border-color: rgba(129,140,248,0.4);
  background: var(--bg-active);
}

.guide-header-row {
  display: flex;
  align-items: flex-start;
  justify-content: space-between;
  gap: 12px;
}

.guide-title {
  font: 700 16px var(--font-sans);
  color: #fff;
  letter-spacing: -0.2px;
}

.guide-course-label {
  font: 500 11px var(--font-mono);
  color: #a78bfa;
  margin-top: 3px;
}

.guide-meta-row {
  display: flex;
  align-items: center;
  gap: 8px;
  flex-wrap: wrap;
}

.complexity-pill {
  font: 600 10px var(--font-mono);
  padding: 2px 8px;
  border-radius: 4px;
  background: rgba(251,191,36,0.12);
  color: #fde047;
  border: 1px solid rgba(251,191,36,0.25);
}

.guide-aim-text {
  font: 400 13px/1.6 var(--font-sans);
  color: var(--text-primary);
}

.guide-algo-box {
  background: var(--bg-base);
  border-left: 3px solid var(--accent);
  padding: 10px 14px;
  border-radius: 0 6px 6px 0;
  font: 400 12px/1.6 var(--font-sans);
  color: var(--text-secondary);
}
.guide-algo-box strong { color: var(--text-primary); }

.guide-code-preview {
  background: var(--bg-deep);
  border: 1px solid var(--border);
  border-radius: 8px;
  padding: 12px 14px;
  font: 12px/1.6 var(--font-mono);
  color: #e2e8f0;
  max-height: 160px;
  overflow-y: auto;
  white-space: pre;
}

.guide-card-footer {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding-top: 8px;
  border-top: 1px solid var(--border);
}

.btn-load-guide {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  padding: 6px 14px;
  border-radius: 8px;
  border: 1px solid rgba(129,140,248,0.3);
  background: rgba(129,140,248,0.12);
  color: #c4b5fd;
  font: 600 12px var(--font-sans);
  cursor: pointer;
  transition: all 0.15s;
}
.btn-load-guide:hover {
  background: var(--accent);
  color: #fff;
  border-color: var(--accent);
  box-shadow: 0 0 16px -2px rgba(129,140,248,0.4);
}


/* ──── 3. Saved Code History & Warning Banner (Problem 4 Fix) ──── */
.history-modal-content {
  max-width: 720px;
  width: 95vw;
  max-height: 85vh;
}

.storage-warning-banner {
  margin: 14px 20px 0;
  display: flex;
  align-items: center;
  gap: 12px;
  padding: 12px 16px;
  border-radius: 10px;
  background: linear-gradient(90deg, rgba(245,158,11,0.12), rgba(217,119,6,0.06));
  border: 1px solid rgba(245,158,11,0.3);
}

.warning-icon-box {
  width: 36px;
  height: 36px;
  border-radius: 8px;
  background: rgba(245,158,11,0.15);
  display: grid;
  place-items: center;
  flex-shrink: 0;
}

.warning-text {
  flex: 1;
}
.warning-title {
  font: 700 12px var(--font-sans);
  color: #fbbf24;
  margin-bottom: 2px;
}
.warning-desc {
  font: 400 11px/1.4 var(--font-sans);
  color: var(--text-secondary);
}

.btn-upgrade-banner {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  padding: 7px 14px;
  border-radius: 8px;
  border: 1px solid rgba(245,158,11,0.4);
  background: rgba(245,158,11,0.15);
  color: #fde047;
  font: 700 11px var(--font-sans);
  cursor: pointer;
  white-space: nowrap;
  transition: all 0.15s;
}
.btn-upgrade-banner:hover {
  background: #f59e0b;
  color: #000;
  box-shadow: 0 0 16px -2px rgba(245,158,11,0.5);
}

.save-snippet-bar {
  display: flex;
  gap: 8px;
  padding: 14px 20px;
  border-bottom: 1px solid var(--border);
}
.save-snippet-bar input {
  flex: 1;
  background: var(--bg-surface);
  border: 1px solid var(--border);
  border-radius: 8px;
  padding: 8px 12px;
  font: 400 13px var(--font-sans);
  color: var(--text-primary);
  outline: none;
}
.save-snippet-bar input:focus {
  border-color: var(--border-focus);
}

.save-submit-btn {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  padding: 8px 16px;
  border-radius: 8px;
  border: none;
  background: var(--green);
  color: #064e3b;
  font: 700 12px var(--font-sans);
  cursor: pointer;
  transition: all 0.15s;
}
.save-submit-btn:hover {
  filter: brightness(1.1);
  transform: translateY(-1px);
}

.history-list {
  flex: 1;
  overflow-y: auto;
  padding: 16px 20px;
  display: flex;
  flex-direction: column;
  gap: 10px;
}

.history-item {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 12px 16px;
  border-radius: var(--radius);
  background: var(--bg-raised);
  border: 1px solid var(--border);
  transition: all 0.15s;
}
.history-item:hover {
  border-color: var(--border-focus);
  background: var(--bg-active);
}

.history-item-left {
  display: flex;
  flex-direction: column;
  gap: 4px;
}
.history-item-title {
  font: 600 13px var(--font-sans);
  color: var(--text-primary);
}
.history-item-meta {
  display: flex;
  align-items: center;
  gap: 8px;
  font: 500 10px var(--font-mono);
  color: var(--text-muted);
}

.history-item-actions {
  display: flex;
  align-items: center;
  gap: 6px;
}
.btn-history-load {
  display: inline-flex;
  align-items: center;
  gap: 4px;
  padding: 5px 10px;
  border-radius: 6px;
  border: 1px solid rgba(129,140,248,0.3);
  background: rgba(129,140,248,0.1);
  color: #c4b5fd;
  font: 600 11px var(--font-sans);
  cursor: pointer;
}
.btn-history-load:hover {
  background: var(--accent);
  color: #fff;
}


/* ──── 4. Cloud Sync Upgrade Modal ──── */
.upgrade-modal-content {
  max-width: 680px;
  width: 95vw;
}

.upgrade-body {
  padding: 24px 28px;
}

.upgrade-hero {
  text-align: center;
  margin-bottom: 24px;
}
.upgrade-icon-circle {
  width: 60px;
  height: 60px;
  border-radius: 50%;
  background: rgba(129,140,248,0.12);
  border: 1px solid rgba(129,140,248,0.3);
  display: grid;
  place-items: center;
  margin: 0 auto 12px;
}
.upgrade-hero h3 {
  font: 700 20px var(--font-sans);
  color: #fff;
  margin-bottom: 6px;
}
.upgrade-hero p {
  font: 400 13px var(--font-sans);
  color: var(--text-secondary);
  max-width: 480px;
  margin: 0 auto;
}

.upgrade-plans {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 16px;
}
@media (max-width: 640px) {
  .upgrade-plans { grid-template-columns: 1fr; }
}

.plan-card {
  border-radius: 12px;
  padding: 20px;
  background: var(--bg-raised);
  border: 1px solid var(--border);
  display: flex;
  flex-direction: column;
  position: relative;
}
.plan-card.pro {
  background: linear-gradient(180deg, #181c2e 0%, #10121d 100%);
  border-color: rgba(129,140,248,0.4);
  box-shadow: 0 0 30px rgba(129,140,248,0.15);
}

.plan-badge {
  font: 700 9px var(--font-mono);
  letter-spacing: 0.05em;
  color: var(--text-muted);
  margin-bottom: 8px;
}
.plan-badge.hot { color: #fde047; }

.plan-card h4 {
  font: 700 16px var(--font-sans);
  color: #fff;
}
.plan-price {
  font: 800 22px var(--font-sans);
  color: #fff;
  margin: 6px 0 14px;
}
.plan-price span {
  font: 400 12px var(--font-sans);
  color: var(--text-muted);
}

.plan-features {
  list-style: none;
  display: flex;
  flex-direction: column;
  gap: 8px;
  font: 400 12px var(--font-sans);
  color: var(--text-secondary);
  margin-bottom: 20px;
  flex: 1;
}
.plan-features strong { color: #fff; }

.btn-pro-activate {
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 8px;
  padding: 10px 16px;
  border-radius: 8px;
  border: none;
  background: linear-gradient(135deg, #6366f1, #8b5cf6);
  color: #fff;
  font: 700 13px var(--font-sans);
  cursor: pointer;
  transition: all 0.2s;
  box-shadow: 0 4px 16px -2px rgba(139,92,246,0.4);
}
.btn-pro-activate:hover {
  transform: translateY(-1px);
  box-shadow: 0 6px 22px -2px rgba(139,92,246,0.6);
}

/* ============================================================
   DAILY CODE TEST & STREAK COUNTER & AD CONTAINER SYSTEM
   ============================================================ */

/* ---------- Streak Badge in Header ---------- */
.streak-badge-header {
  display: flex;
  align-items: center;
  gap: 6px;
  padding: 5px 12px;
  border-radius: 99px;
  background: linear-gradient(135deg, rgba(245, 158, 11, 0.12), rgba(239, 68, 68, 0.12));
  border: 1px solid rgba(245, 158, 11, 0.35);
  font: 600 11px var(--font-sans);
  color: #fef08a;
  box-shadow: 0 0 16px -4px rgba(245, 158, 11, 0.3);
  cursor: pointer;
  transition: all 0.2s;
  user-select: none;
}
.streak-badge-header:hover {
  transform: translateY(-1px);
  border-color: rgba(245, 158, 11, 0.6);
  box-shadow: 0 0 20px -2px rgba(245, 158, 11, 0.45);
}
.streak-flame {
  font-size: 14px;
  animation: flameBounce 1.5s ease-in-out infinite;
  display: inline-block;
  transform-origin: center bottom;
}
@keyframes flameBounce {
  0%, 100% { transform: scale(1) rotate(0deg); }
  50% { transform: scale(1.15) rotate(3deg); }
}
.streak-label {
  color: #fcd34d;
  font-size: 11px;
}
.streak-count-val {
  color: #fff;
  font-weight: 700;
  text-shadow: 0 0 8px rgba(245, 158, 11, 0.5);
}

/* ---------- Top Leaderboard Ad Banner (728x90) ---------- */
.top-ad-banner-wrapper {
  background: var(--bg-surface);
  border-bottom: 1px solid var(--border);
  padding: 4px 16px;
  display: flex;
  justify-content: center;
  align-items: center;
  flex-shrink: 0;
  z-index: 10;
}
.ad-container-frame {
  position: relative;
  background: linear-gradient(135deg, rgba(24, 24, 27, 0.85), rgba(39, 39, 42, 0.65));
  border: 1px dashed rgba(161, 161, 170, 0.25);
  border-radius: 8px;
  overflow: hidden;
  transition: all 0.25s ease;
}
.ad-container-frame.ad-refreshed {
  animation: adPulse 0.5s ease-out;
}
@keyframes adPulse {
  0% { transform: scale(1); box-shadow: 0 0 0 rgba(129, 140, 248, 0); }
  50% { transform: scale(1.008); box-shadow: 0 0 20px rgba(129, 140, 248, 0.35); border-color: rgba(129, 140, 248, 0.6); }
  100% { transform: scale(1); box-shadow: 0 0 0 rgba(129, 140, 248, 0); }
}
.top-leaderboard {
  width: 100%;
  max-width: 728px;
  min-height: 58px;
  padding: 6px 14px;
  display: flex;
  flex-direction: column;
  justify-content: space-between;
}
.ad-meta-bar {
  display: flex;
  justify-content: space-between;
  align-items: center;
  margin-bottom: 4px;
}
.ad-badge-tag {
  font: 700 8.5px var(--font-mono);
  letter-spacing: 0.08em;
  color: var(--text-muted);
}
.ad-impression-badge {
  font: 600 8.5px var(--font-mono);
  color: #34d399;
  background: rgba(52, 211, 153, 0.08);
  border: 1px solid rgba(52, 211, 153, 0.25);
  padding: 1px 6px;
  border-radius: 4px;
}
.ad-content-box {
  display: flex;
  align-items: center;
  gap: 12px;
}
.ad-sponsor-pill {
  font: 800 8.5px var(--font-sans);
  background: #f59e0b;
  color: #000;
  padding: 2px 5px;
  border-radius: 4px;
  letter-spacing: 0.05em;
  flex-shrink: 0;
}
.ad-sponsor-details {
  flex: 1;
  display: flex;
  flex-direction: column;
  min-width: 0;
}
.ad-sponsor-headline {
  font: 600 12px var(--font-sans);
  color: #f4f4f5;
  white-space: nowrap;
  overflow: hidden;
  text-overflow: ellipsis;
}
.ad-sponsor-sub {
  font: 400 10.5px var(--font-sans);
  color: var(--text-muted);
  white-space: nowrap;
  overflow: hidden;
  text-overflow: ellipsis;
}
.ad-action-btn {
  font: 600 11px var(--font-sans);
  padding: 4px 10px;
  border-radius: 6px;
  background: var(--accent);
  color: #fff;
  border: none;
  cursor: pointer;
  white-space: nowrap;
  flex-shrink: 0;
  transition: all 0.15s;
}
.ad-action-btn:hover {
  background: #4f46e5;
  box-shadow: 0 0 10px rgba(129, 140, 248, 0.4);
}
.ad-refresh-shimmer {
  position: absolute;
  top: 0; left: -100%; width: 200%; height: 100%;
  background: linear-gradient(90deg, transparent, rgba(255, 255, 255, 0.08), transparent);
  animation: shimmerAnim 0.7s infinite;
  pointer-events: none;
}
@keyframes shimmerAnim {
  0% { transform: translateX(0); }
  100% { transform: translateX(50%); }
}

/* ---------- Workspace Split Layout Base ---------- */
.left-sidebar {
  width: 320px;
  flex-shrink: 0;
  background: var(--bg-surface);
  border-right: 1px solid var(--border);
  overflow-y: auto;
  padding: 12px;
  display: flex;
  flex-direction: column;
  gap: 12px;
}
.workspace-editor-main {
  flex: 1;
  min-width: 0;
  display: flex;
  flex-direction: column;
  height: 100%;
  overflow: hidden;
}

/* ---------- Daily Mind Workout Card ---------- */
.daily-workout-card {
  background: var(--bg-base);
  border: 1px solid var(--border);
  border-radius: 12px;
  padding: 12px;
  display: flex;
  flex-direction: column;
  gap: 10px;
  box-shadow: 0 4px 16px -6px rgba(0, 0, 0, 0.4);
}
.workout-header {
  display: flex;
  justify-content: space-between;
  align-items: center;
}
.workout-title-row {
  display: flex;
  align-items: center;
  gap: 8px;
}
.workout-icon-box {
  width: 30px;
  height: 30px;
  border-radius: 8px;
  background: rgba(250, 204, 21, 0.1);
  border: 1px solid rgba(250, 204, 21, 0.25);
  display: grid;
  place-items: center;
}
.workout-heading {
  font: 700 13px var(--font-sans);
  color: #f4f4f5;
  margin: 0;
}
.workout-sub {
  font: 500 9.5px var(--font-sans);
  color: var(--text-muted);
}
.sidebar-streak-pill {
  display: flex;
  align-items: center;
  gap: 4px;
  font: 700 11px var(--font-sans);
  color: #facc15;
  background: rgba(250, 204, 21, 0.1);
  border: 1px solid rgba(250, 204, 21, 0.3);
  padding: 2px 7px;
  border-radius: 99px;
}
.flame-mini {
  font-size: 12px;
}

/* Difficulty Toggle */
.difficulty-toggle-wrapper {
  display: flex;
  flex-direction: column;
  gap: 5px;
}
.toggle-label {
  font: 600 9.5px var(--font-sans);
  text-transform: uppercase;
  letter-spacing: 0.06em;
  color: var(--text-muted);
}
.difficulty-toggle-group {
  display: flex;
  background: var(--bg-raised);
  padding: 3px;
  border-radius: 8px;
  border: 1px solid var(--border);
  gap: 4px;
}
.diff-toggle-btn {
  flex: 1;
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 5px;
  font: 600 11px var(--font-sans);
  padding: 5px 8px;
  border-radius: 6px;
  border: none;
  background: transparent;
  color: var(--text-secondary);
  cursor: pointer;
  transition: all 0.15s;
}
.diff-toggle-btn:hover {
  color: var(--text-primary);
  background: var(--bg-hover);
}
.diff-toggle-btn.active {
  background: var(--accent);
  color: #fff;
  box-shadow: 0 2px 8px -2px rgba(129, 140, 248, 0.5);
}

/* Quiz Container */
.quiz-container {
  display: flex;
  flex-direction: column;
  gap: 9px;
}
.quiz-question-meta {
  display: flex;
  justify-content: space-between;
  align-items: center;
  font: 600 10px var(--font-mono);
}
.quiz-lang-tag {
  background: rgba(167, 139, 250, 0.15);
  color: #c4b5fd;
  border: 1px solid rgba(167, 139, 250, 0.3);
  padding: 2px 6px;
  border-radius: 4px;
}
.quiz-qnum {
  color: var(--text-muted);
}
.quiz-prompt {
  font: 600 11.5px var(--font-sans);
  color: var(--text-primary);
  line-height: 1.4;
}
.quiz-code-snippet {
  background: #09090b;
  border: 1px solid rgba(255, 255, 255, 0.08);
  border-radius: 7px;
  padding: 8px 10px;
  font-family: var(--font-mono);
  font-size: 11px;
  line-height: 1.45;
  color: #a5f3fc;
  overflow-x: auto;
  margin: 0;
  max-height: 140px;
}
.quiz-options-list {
  display: flex;
  flex-direction: column;
  gap: 6px;
}
.quiz-option-item {
  display: flex;
  align-items: center;
  gap: 8px;
  padding: 7px 10px;
  border-radius: 7px;
  background: var(--bg-raised);
  border: 1px solid var(--border);
  cursor: pointer;
  transition: all 0.15s;
  user-select: none;
}
.quiz-option-item:hover:not(.disabled) {
  border-color: var(--border-hover);
  background: var(--bg-hover);
}
.quiz-option-item.correct {
  background: rgba(52, 211, 153, 0.15) !important;
  border-color: #34d399 !important;
  color: #6ee7b7 !important;
}
.quiz-option-item.incorrect {
  background: rgba(248, 113, 113, 0.15) !important;
  border-color: #f87171 !important;
  color: #fca5a5 !important;
}
.quiz-option-item.disabled {
  cursor: default;
}
.option-label-circle {
  width: 20px;
  height: 20px;
  border-radius: 50%;
  background: rgba(255, 255, 255, 0.08);
  display: grid;
  place-items: center;
  font: 700 10px var(--font-mono);
  flex-shrink: 0;
  color: var(--text-secondary);
}
.quiz-option-item.correct .option-label-circle {
  background: #10b981;
  color: #000;
}
.quiz-option-item.incorrect .option-label-circle {
  background: #ef4444;
  color: #fff;
}
.option-text {
  font: 500 11px var(--font-mono);
  line-height: 1.35;
  color: var(--text-primary);
  flex: 1;
}

/* Explanation Box */
.quiz-explanation-box {
  background: rgba(15, 23, 42, 0.85);
  border: 1px solid rgba(129, 140, 248, 0.25);
  border-radius: 8px;
  padding: 9px 10px;
  display: flex;
  flex-direction: column;
  gap: 5px;
  animation: fadeIn 0.25s ease-out;
}
.explanation-header {
  display: flex;
  align-items: center;
  gap: 6px;
  font: 700 11px var(--font-sans);
}
.explanation-header.correct { color: #34d399; }
.explanation-header.incorrect { color: #f87171; }
.explanation-status-icon {
  font-size: 13px;
}
.explanation-text {
  font: 400 11px var(--font-sans);
  color: #cbd5e1;
  line-height: 1.45;
  margin: 0;
}
.explanation-streak-notice {
  font: 700 10px var(--font-sans);
  color: #facc15;
  margin-top: 2px;
}

/* Quiz Footer Actions */
.quiz-footer-actions {
  display: flex;
  justify-content: flex-end;
  margin-top: 2px;
}
.btn-quiz-next {
  display: flex;
  align-items: center;
  gap: 5px;
  font: 600 11px var(--font-sans);
  padding: 5px 11px;
  border-radius: 6px;
  background: var(--bg-raised);
  border: 1px solid var(--border);
  color: var(--text-primary);
  cursor: pointer;
  transition: all 0.15s;
}
.btn-quiz-next:hover {
  background: var(--bg-hover);
  border-color: var(--border-hover);
}

/* ---------- Left Sidebar Ad Container ---------- */
.left-sidebar-ad {
  width: 100%;
  min-height: 130px;
  padding: 10px;
  display: flex;
  flex-direction: column;
  justify-content: space-between;
  gap: 6px;
}
.ad-sidebar-content {
  display: flex;
  flex-direction: column;
  gap: 4px;
}
.ad-side-title {
  font: 700 11.5px var(--font-sans);
  color: #f4f4f5;
  margin: 0;
}
.ad-side-desc {
  font: 400 10px var(--font-sans);
  color: var(--text-muted);
  line-height: 1.35;
  margin: 0;
}
.side-btn {
  align-self: flex-start;
  margin-top: 4px;
  font-size: 10.5px;
  padding: 4px 9px;
}

/* Responsive adjustments */
@media (max-width: 900px) {
  .left-sidebar { width: 280px; }
  .top-leaderboard { max-width: 100%; }
}

/* ---------- Ad-Blocker Notice Banner (Problem 4 Fix) ---------- */
.adblock-notice-banner {
  background: linear-gradient(135deg, rgba(24, 24, 27, 0.95), rgba(39, 39, 42, 0.9));
  border-bottom: 1px solid rgba(250, 204, 21, 0.3);
  padding: 8px 20px;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 16px;
  z-index: 15;
  box-shadow: 0 4px 12px rgba(0, 0, 0, 0.35);
  animation: slideDown 0.3s ease-out;
}
@keyframes slideDown {
  from { transform: translateY(-100%); opacity: 0; }
  to { transform: translateY(0); opacity: 1; }
}
.adblock-notice-content {
  display: flex;
  align-items: center;
  gap: 12px;
  flex: 1;
}
.adblock-badge {
  display: flex;
  align-items: center;
  gap: 6px;
  font: 700 10px var(--font-mono);
  background: rgba(250, 204, 21, 0.12);
  border: 1px solid rgba(250, 204, 21, 0.3);
  color: #facc15;
  padding: 3px 8px;
  border-radius: 6px;
  white-space: nowrap;
}
.adblock-text {
  font: 500 11.5px var(--font-sans);
  color: #e4e4e7;
  line-height: 1.4;
  margin: 0;
}
.adblock-actions {
  display: flex;
  align-items: center;
  gap: 8px;
  flex-shrink: 0;
}
.btn-adblock-whitelist {
  display: flex;
  align-items: center;
  gap: 5px;
  font: 600 11px var(--font-sans);
  padding: 5px 12px;
  border-radius: 6px;
  background: rgba(129, 140, 248, 0.15);
  border: 1px solid rgba(129, 140, 248, 0.35);
  color: #c4b5fd;
  cursor: pointer;
  transition: all 0.15s;
}
.btn-adblock-whitelist:hover {
  background: rgba(129, 140, 248, 0.25);
  color: #fff;
}
.btn-adblock-dismiss {
  font: 600 11px var(--font-sans);
  padding: 5px 12px;
  border-radius: 6px;
  background: var(--bg-raised);
  border: 1px solid var(--border);
  color: var(--text-secondary);
  cursor: pointer;
  transition: all 0.15s;
}
.btn-adblock-dismiss:hover {
  background: var(--bg-hover);
  color: var(--text-primary);
}

/* ============================================================
   3-COLUMN IDE WORKSPACE
   Column 1 (Left):   Problem / Instructions & Examples
   Column 2 (Middle): Code Editor (Input Code)
   Column 3 (Right):  Console Output & Preview
   ============================================================ */

.workspace {
  flex: 1;
  min-height: 0;
  display: flex;
  padding: 10px 14px;
  background: var(--bg-deep);
  height: calc(100vh - var(--header-h));
  overflow: hidden;
  box-sizing: border-box;
}

.workspace-body-split {
  flex: 1;
  width: 100%;
  max-width: 100%;
  height: 100%;
  margin: 0;
  display: flex;
  flex-direction: row;
  border-radius: 12px;
  border: 1px solid rgba(255, 255, 255, 0.08);
  background: var(--bg-surface);
  box-shadow: 0 16px 40px -10px rgba(0, 0, 0, 0.7);
  overflow: hidden;
}

/* ---------- COLUMN 1 (LEFT): Dedicated Google AdSense Slot ---------- */
.workspace-left-ad {
  flex: 0 0 280px;
  min-width: 180px;
  max-width: 420px;
  height: 100%;
  display: flex;
  flex-direction: column;
  background: var(--bg-surface);
  border-right: 1px solid var(--border);
  overflow: hidden;
}

.ad-slot-header {
  padding: 8px 12px;
  background: var(--bg-base);
  border-bottom: 1px solid var(--border);
  display: flex;
  align-items: center;
  justify-content: center;
  flex-shrink: 0;
}

.ad-slot-badge {
  font: 700 9px var(--font-mono);
  color: #64748b;
  letter-spacing: 0.1em;
  text-transform: uppercase;
}

.ad-slot-container {
  flex: 1;
  display: flex;
  align-items: center;
  justify-content: center;
  padding: 16px;
  background: #060912;
  overflow: auto;
}

.google-ad-placeholder {
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  text-align: center;
  gap: 10px;
  padding: 24px 16px;
  border: 1px dashed rgba(255, 255, 255, 0.14);
  border-radius: 10px;
  background: rgba(255, 255, 255, 0.02);
  width: 100%;
  max-width: 250px;
  min-height: 480px;
}

.ad-ph-icon {
  width: 44px;
  height: 44px;
  border-radius: 50%;
  background: rgba(255, 255, 255, 0.05);
  display: flex;
  align-items: center;
  justify-content: center;
}

.ad-ph-title {
  font: 700 13px var(--font-sans);
  color: #cbd5e1;
}

.ad-ph-desc {
  font: 500 11px var(--font-mono);
  color: #64748b;
}

.ad-ph-note {
  font: 400 10.5px var(--font-sans);
  color: #475569;
  max-width: 180px;
  line-height: 1.4;
  margin-top: 6px;
}

/* ---------- COLUMN 1 (LEFT): Problem / Instructions ---------- */
.workspace-left-problem {
  flex: 0 0 320px;
  min-width: 240px;
  max-width: 480px;
  height: 100%;
  display: flex;
  flex-direction: column;
  background: var(--bg-surface);
  border-right: none;
  overflow: hidden;
}

.problem-panel-header {
  padding: 10px 14px;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 10px;
  background: var(--bg-base);
  border-bottom: 1px solid var(--border);
  flex-shrink: 0;
}

.problem-select-wrapper {
  display: flex;
  align-items: center;
  gap: 8px;
  flex: 1;
  min-width: 0;
}

.problem-label {
  font: 700 10px var(--font-mono);
  color: var(--text-muted);
  letter-spacing: 0.05em;
  white-space: nowrap;
}

.problem-selector {
  flex: 1;
  min-width: 0;
  background: var(--bg-raised);
  border: 1px solid var(--border);
  border-radius: 6px;
  color: var(--text-primary);
  font: 600 12px var(--font-sans);
  padding: 5px 8px;
  cursor: pointer;
  outline: none;
  transition: border-color 0.15s;
}
.problem-selector:focus {
  border-color: var(--accent);
}

.problem-diff-badge {
  font: 700 10.5px var(--font-mono);
  padding: 2px 8px;
  border-radius: 99px;
  white-space: nowrap;
}
.problem-diff-badge.easy {
  background: rgba(52, 211, 153, 0.15);
  color: #34d399;
  border: 1px solid rgba(52, 211, 153, 0.3);
}
.problem-diff-badge.medium {
  background: rgba(251, 191, 36, 0.15);
  color: #fbbf24;
  border: 1px solid rgba(251, 191, 36, 0.3);
}

.problem-panel-body {
  flex: 1;
  overflow-y: auto;
  padding: 16px 16px;
  display: flex;
  flex-direction: column;
  gap: 14px;
  font-family: var(--font-sans);
}

.problem-title {
  font-size: 17px;
  font-weight: 700;
  color: #f8fafc;
  line-height: 1.3;
  margin: 0;
}

.problem-tags {
  display: flex;
  flex-wrap: wrap;
  gap: 6px;
}
.problem-tag {
  font: 500 11px var(--font-mono);
  padding: 2px 8px;
  border-radius: 4px;
  background: rgba(129, 140, 248, 0.1);
  border: 1px solid rgba(129, 140, 248, 0.2);
  color: #c7d2fe;
}

.problem-description {
  font-size: 13px;
  color: #cbd5e1;
  line-height: 1.6;
}
.problem-description p {
  margin-bottom: 8px;
}
.problem-description code,
.problem-example-box code {
  background: rgba(255, 255, 255, 0.08);
  padding: 2px 5px;
  border-radius: 4px;
  font-family: var(--font-mono);
  font-size: 12px;
  color: #38bdf8;
}

.problem-section-heading {
  font: 700 11px var(--font-sans);
  text-transform: uppercase;
  letter-spacing: 0.05em;
  color: #94a3b8;
  margin-top: 4px;
}

.problem-example-box {
  background: var(--bg-deep);
  border: 1px solid var(--border);
  border-radius: 8px;
  padding: 10px 12px;
  font-size: 12px;
  line-height: 1.6;
  color: #e2e8f0;
  display: flex;
  flex-direction: column;
  gap: 4px;
}
.problem-example-box .example-explain {
  color: var(--text-muted);
  font-size: 11.5px;
  margin-top: 2px;
}

.problem-constraints {
  padding-left: 20px;
  font-size: 12px;
  color: #94a3b8;
  line-height: 1.6;
}

.btn-load-problem-code {
  margin-top: auto;
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 8px;
  padding: 9px 14px;
  border-radius: 8px;
  background: rgba(129, 140, 248, 0.12);
  border: 1px solid rgba(129, 140, 248, 0.35);
  color: #e0e7ff;
  font: 600 12.5px var(--font-sans);
  cursor: pointer;
  transition: all 0.15s;
}
.btn-load-problem-code:hover {
  background: rgba(129, 140, 248, 0.22);
  border-color: rgba(129, 140, 248, 0.55);
}

/* ---------- COLUMN 2 (MIDDLE): Code Input & Editor ---------- */
.workspace-left-editor {
  flex: 1 1 45%;
  min-width: 340px;
  height: 100%;
  display: flex;
  flex-direction: column;
  overflow: hidden;
  background: var(--bg-deep);
}

.workspace-left-editor .lang-bar {
  background: var(--bg-base);
  border-bottom: 1px solid var(--border);
  padding: 0 12px;
  flex-shrink: 0;
}

.workspace-left-editor .editor-panel.full-height {
  flex: 1;
  min-height: 0;
  height: 100%;
  position: relative;
  display: flex;
  flex-direction: column;
}

/* ---------- COLUMN 3 (RIGHT): Output Panel ---------- */
.workspace-right-column {
  flex: 0 0 380px;
  min-width: 280px;
  max-width: 580px;
  height: 100%;
  display: flex;
  flex-direction: column;
  overflow: hidden;
  background: var(--bg-surface);
  border-left: none;
}

.workspace-right-column .output-panel {
  flex: 1 1 100%;
  height: 100%;
  min-height: 0;
  display: flex;
  flex-direction: column;
  overflow: hidden;
  background: var(--bg-surface);
  border-top: none;
}

/* Fullscreen Output Box Mode */
.output-panel.fullscreen-output {
  position: fixed !important;
  top: 0 !important;
  left: 0 !important;
  right: 0 !important;
  bottom: 0 !important;
  width: 100vw !important;
  height: 100vh !important;
  max-width: 100vw !important;
  max-height: 100vh !important;
  z-index: 999999 !important;
  background: var(--bg-deep) !important;
  border: none !important;
  border-radius: 0 !important;
  box-shadow: 0 0 50px rgba(0, 0, 0, 0.9) !important;
  display: flex !important;
  flex-direction: column !important;
}

.output-panel.fullscreen-output .output-tabs {
  padding: 8px 16px !important;
  background: var(--bg-surface) !important;
  border-bottom: 1px solid rgba(255, 255, 255, 0.12) !important;
}

.output-panel.fullscreen-output .output-tabs .output-tab {
  padding: 8px 18px !important;
  font-size: 13px !important;
}

.output-panel.fullscreen-output .console-output {
  flex: 1 1 100% !important;
  height: auto !important;
  max-height: none !important;
  padding: 20px 24px !important;
  font-size: 14px !important;
}

.output-panel.fullscreen-output .web-preview-container,
.output-panel.fullscreen-output .testcases-panel {
  flex: 1 1 100% !important;
  height: auto !important;
  max-height: none !important;
}

/* ---------- Vertical Split Handles between Columns ---------- */
.split-handle-vertical {
  width: 6px;
  background: var(--border);
  cursor: col-resize;
  position: relative;
  transition: background 0.15s;
  flex-shrink: 0;
  display: grid;
  place-items: center;
  z-index: 10;
}
.split-handle-vertical:hover, .split-handle-vertical.dragging {
  background: var(--accent);
}
.handle-grip-v {
  width: 2px;
  height: 32px;
  background: rgba(255, 255, 255, 0.25);
  border-radius: 99px;
  transition: all 0.15s;
}
.split-handle-vertical:hover .handle-grip-v,
.split-handle-vertical.dragging .handle-grip-v {
  background: #fff;
  height: 44px;
}

/* Clean Output Area: Keep Workout Slot hidden in practice view for clean focused experience */
.daily-workout-slot,
.workout-collapsed-bar,
.workout-toggle-tab-btn,
#workoutSplitHandle {
  display: none !important;
}

.daily-workout-slot {
  display: none;
  flex: 1 1 50%;
  min-height: 140px;
  height: 50%;
  display: flex;
  flex-direction: column;
  overflow: hidden;
  background: var(--bg-base);
  border-top: 1px solid var(--border);
  transition: all 0.2s ease;
}

.workout-slot-header {
  padding: 8px 14px;
  display: flex;
  align-items: center;
  justify-content: space-between;
  background: var(--bg-surface);
  border-bottom: 1px solid var(--border);
  flex-shrink: 0;
}

.workout-slot-body {
  flex: 1;
  overflow-y: auto;
  padding: 12px 14px;
  display: flex;
  flex-direction: column;
  gap: 10px;
}

/* Toggle buttons in output tabs */
.workout-toggle-tab-btn {
  display: flex;
  align-items: center;
  gap: 6px;
  padding: 4px 10px;
  border-radius: 6px;
  background: rgba(250, 204, 21, 0.08);
  border: 1px solid rgba(250, 204, 21, 0.25);
  color: #fef08a;
  font: 600 11px var(--font-sans);
  cursor: pointer;
  transition: all 0.15s;
  margin-right: 6px;
}
.workout-toggle-tab-btn:hover {
  background: rgba(250, 204, 21, 0.18);
  border-color: rgba(250, 204, 21, 0.45);
}
.streak-mini-chip {
  font-size: 10px;
  color: #facc15;
}

/* Collapsed Bar indicator when Workout is closed */
.workout-collapsed-bar {
  padding: 6px 12px;
  background: var(--bg-surface);
  border-top: 1px solid var(--border);
  flex-shrink: 0;
  animation: fadeIn 0.2s ease;
}
.btn-reopen-workout {
  width: 100%;
  display: flex;
  align-items: center;
  gap: 8px;
  padding: 6px 12px;
  border-radius: 6px;
  background: var(--bg-raised);
  border: 1px solid var(--border);
  color: var(--text-primary);
  font: 600 11px var(--font-sans);
  cursor: pointer;
  transition: all 0.15s;
}
.btn-reopen-workout:hover {
  background: var(--bg-hover);
  border-color: rgba(250, 204, 21, 0.4);
}

/* Workout Closed State */
.workspace-right-column.workout-closed .output-panel {
  flex: 1 1 100% !important;
  height: 100% !important;
}

.workspace-right-column.workout-closed .split-handle-horizontal,
.workspace-right-column.workout-closed .daily-workout-slot {
  display: none !important;
}

.workspace-right-column.workout-closed .workout-collapsed-bar {
  display: none !important;
}

.workout-toggle-tab-btn {
  display: flex;
  align-items: center;
  gap: 6px;
  padding: 4px 10px;
  border-radius: 6px;
  background: rgba(250, 204, 21, 0.08);
  border: 1px solid rgba(250, 204, 21, 0.25);
  color: #fef08a;
  font: 600 11px var(--font-sans);
  cursor: pointer;
  transition: all 0.15s;
  margin-right: 6px;
}

.workout-toggle-tab-btn.active {
  background: rgba(250, 204, 21, 0.2);
  border-color: rgba(250, 204, 21, 0.5);
  color: #fff;
  box-shadow: 0 0 8px rgba(250, 204, 21, 0.2);
}

.workout-toggle-tab-btn:not(.active) {
  opacity: 0.8;
  filter: grayscale(0.2);
}

/* ============================================================
   NEW FEATURES: EDITOR CONTROLS, THEMES, STDIN & TEST CASES
   ============================================================ */

/* 1. Editor Controls Group (Font Size & Theme Dropdowns) */
.editor-controls-group {
  display: flex;
  align-items: center;
  gap: 5px;
}

.editor-select-sm {
  background: var(--bg-surface);
  border: 1px solid var(--border);
  color: var(--text-secondary);
  font: 500 11.5px var(--font-sans);
  padding: 5px 8px;
  border-radius: 6px;
  outline: none;
  cursor: pointer;
  transition: all 0.15s;
}

.editor-select-sm:hover,
.editor-select-sm:focus {
  border-color: rgba(56, 189, 248, 0.4);
  color: var(--text-primary);
  background: var(--bg-raised);
}

/* 2. Editor Themes */
.code-editor-wrapper.theme-vsdark {
  background: #080a12;
}
.code-editor-wrapper.theme-vsdark .editor-gutter {
  background: #05070d;
  color: #64748b;
  border-right-color: rgba(255, 255, 255, 0.08);
}
.code-editor-wrapper.theme-vsdark .fallback-editor {
  color: #f1f5f9;
  caret-color: #38bdf8;
}

.code-editor-wrapper.theme-monokai {
  background: #272822 !important;
}
.code-editor-wrapper.theme-monokai .editor-gutter {
  background: #1e1f1c !important;
  color: #75715e !important;
  border-right: 1px solid #3e3d32 !important;
}
.code-editor-wrapper.theme-monokai .fallback-editor {
  color: #f8f8f2 !important;
  caret-color: #f92672 !important;
}

.code-editor-wrapper.theme-dracula {
  background: #282a36 !important;
}
.code-editor-wrapper.theme-dracula .editor-gutter {
  background: #21222c !important;
  color: #6272a4 !important;
  border-right: 1px solid #44475a !important;
}
.code-editor-wrapper.theme-dracula .fallback-editor {
  color: #f8f8f2 !important;
  caret-color: #bd93f9 !important;
}

.code-editor-wrapper.theme-light {
  background: #ffffff !important;
}
.code-editor-wrapper.theme-light .editor-gutter {
  background: #f8fafc !important;
  color: #94a3b8 !important;
  border-right: 1px solid #e2e8f0 !important;
}
.code-editor-wrapper.theme-light .fallback-editor {
  color: #0f172a !important;
  caret-color: #2563eb !important;
}

/* 3. Share & Lab PDF Toolbar Buttons */
.share-code-btn {
  display: flex;
  align-items: center;
  gap: 6px;
  padding: 6px 12px;
  border-radius: 8px;
  background: rgba(192, 132, 252, 0.1);
  border: 1px solid rgba(192, 132, 252, 0.25);
  color: #d8b4fe;
  font: 600 12px var(--font-sans);
  cursor: pointer;
  transition: all 0.15s;
}
.share-code-btn:hover {
  background: rgba(192, 132, 252, 0.2);
  border-color: rgba(192, 132, 252, 0.5);
  color: #fff;
  transform: translateY(-1px);
}

.lab-pdf-btn {
  display: flex;
  align-items: center;
  gap: 6px;
  padding: 6px 12px;
  border-radius: 8px;
  background: rgba(16, 185, 129, 0.1);
  border: 1px solid rgba(16, 185, 129, 0.25);
  color: #6ee7b7;
  font: 600 12px var(--font-sans);
  cursor: pointer;
  transition: all 0.15s;
}
.lab-pdf-btn:hover {
  background: rgba(16, 185, 129, 0.2);
  border-color: rgba(16, 185, 129, 0.5);
  color: #fff;
  transform: translateY(-1px);
}

/* 4. Collapsible Custom Input (stdin) Panel */
.custom-stdin-panel {
  background: #090d16;
  border-bottom: 1px solid var(--border);
  transition: all 0.2s ease;
}

.custom-stdin-header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 6px 14px;
  cursor: pointer;
  user-select: none;
  background: rgba(15, 23, 42, 0.7);
  transition: background 0.15s;
}
.custom-stdin-header:hover {
  background: rgba(30, 41, 59, 0.8);
}

.custom-stdin-title {
  display: flex;
  align-items: center;
  gap: 7px;
  font: 600 11.5px var(--font-sans);
  color: var(--text-primary);
}

.stdin-hint {
  font: 500 10px var(--font-mono);
  color: var(--cyan);
  background: rgba(56, 189, 248, 0.1);
  padding: 1px 6px;
  border-radius: 4px;
  border: 1px solid rgba(56, 189, 248, 0.2);
}

.custom-stdin-controls {
  display: flex;
  align-items: center;
  gap: 6px;
}

.stdin-btn-text {
  background: transparent;
  border: none;
  color: var(--text-muted);
  font: 500 11px var(--font-sans);
  cursor: pointer;
  padding: 2px 6px;
  border-radius: 4px;
  transition: all 0.15s;
}
.stdin-btn-text:hover {
  color: var(--red);
  background: rgba(239, 68, 68, 0.1);
}

.stdin-toggle-btn {
  display: flex;
  align-items: center;
  gap: 4px;
  background: rgba(255, 255, 255, 0.05);
  border: 1px solid var(--border);
  color: var(--text-secondary);
  font: 500 11px var(--font-sans);
  padding: 2px 8px;
  border-radius: 5px;
  cursor: pointer;
  transition: all 0.15s;
}
.stdin-toggle-btn:hover {
  background: rgba(255, 255, 255, 0.1);
  color: var(--text-primary);
}

.custom-stdin-body {
  padding: 8px 12px;
  background: #060911;
  border-top: 1px solid rgba(255, 255, 255, 0.05);
}

.custom-stdin-textarea {
  width: 100%;
  height: 65px;
  background: #04060a;
  border: 1px solid rgba(255, 255, 255, 0.1);
  border-radius: 6px;
  color: #38bdf8;
  font: 12.5px/18px var(--font-mono);
  padding: 8px 10px;
  resize: vertical;
  outline: none;
  white-space: pre;
}
.custom-stdin-textarea:focus {
  border-color: #38bdf8;
  box-shadow: 0 0 0 1px rgba(56, 189, 248, 0.2);
}

/* 5. Automated Test Cases Panel */
.testcases-panel {
  flex: 1;
  display: flex;
  flex-direction: column;
  overflow-y: auto;
  background: var(--bg-deep);
  padding: 12px 16px;
  gap: 12px;
}

.testcases-toolbar {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding-bottom: 10px;
  border-bottom: 1px solid var(--border);
}

.testcases-info {
  display: flex;
  flex-direction: column;
  gap: 2px;
}

.testcases-heading {
  font: 700 13px var(--font-sans);
  color: var(--text-primary);
}

.testcases-sub {
  font: 500 11px var(--font-sans);
  color: var(--text-muted);
}

.btn-run-tests {
  display: flex;
  align-items: center;
  gap: 6px;
  padding: 6px 14px;
  border-radius: 8px;
  background: linear-gradient(135deg, #16a34a, #22c55e);
  border: none;
  color: #fff;
  font: 700 12px var(--font-sans);
  cursor: pointer;
  transition: all 0.2s;
  box-shadow: 0 4px 12px rgba(34, 197, 94, 0.3);
}
.btn-run-tests:hover {
  background: linear-gradient(135deg, #15803d, #16a34a);
  transform: translateY(-1px);
}

.testcases-results {
  display: flex;
  flex-direction: column;
  gap: 10px;
}

.testcase-card {
  background: #090d16;
  border: 1px solid var(--border);
  border-radius: 8px;
  padding: 12px;
  display: flex;
  flex-direction: column;
  gap: 8px;
  transition: border-color 0.2s;
}
.testcase-card.passed {
  border-color: rgba(34, 197, 94, 0.4);
  background: rgba(34, 197, 94, 0.04);
}
.testcase-card.failed {
  border-color: rgba(239, 68, 68, 0.4);
  background: rgba(239, 68, 68, 0.04);
}

.testcase-card-header {
  display: flex;
  align-items: center;
  justify-content: space-between;
}

.testcase-number {
  font: 700 12px var(--font-mono);
  color: var(--text-primary);
}

.testcase-status-badge {
  font: 700 10.5px var(--font-mono);
  padding: 2px 8px;
  border-radius: 99px;
  letter-spacing: 0.03em;
}
.testcase-status-badge.idle {
  background: rgba(255, 255, 255, 0.08);
  color: var(--text-muted);
}
.testcase-status-badge.passed {
  background: rgba(34, 197, 94, 0.15);
  color: #4ade80;
  border: 1px solid rgba(34, 197, 94, 0.3);
}
.testcase-status-badge.failed {
  background: rgba(239, 68, 68, 0.15);
  color: #f87171;
  border: 1px solid rgba(239, 68, 68, 0.3);
}

.testcase-io-grid {
  display: flex;
  flex-direction: column;
  gap: 6px;
  font: 11.5px var(--font-mono);
}

.testcase-io-block {
  display: flex;
  flex-direction: column;
  gap: 3px;
}

.testcase-io-label {
  font: 600 10px var(--font-sans);
  color: var(--text-muted);
  text-transform: uppercase;
  letter-spacing: 0.05em;
}

.testcase-io-code {
  background: #04060a;
  border: 1px solid rgba(255, 255, 255, 0.06);
  border-radius: 5px;
  padding: 6px 10px;
  color: #e2e8f0;
  white-space: pre-wrap;
  word-break: break-all;
}
.testcase-io-code.expected {
  color: #86efac;
}
.testcase-io-code.actual {
  color: #fca5a5;
}

/* ============================================================
   ADSENSE COMPLIANCE: HEADER LINKS, SEO CONTENT & FOOTER
   ============================================================ */

/* Header Nav Links */
.nav-tab-link {
  display: flex;
  align-items: center;
  gap: 6px;
  padding: 6px 14px;
  border-radius: 8px;
  color: var(--text-muted);
  text-decoration: none;
  font: 500 12.5px var(--font-sans);
  transition: all 0.15s;
}
.nav-tab-link:hover {
  color: var(--text-primary);
  background: var(--bg-surface);
}

/* Educational SEO Section */
.educational-seo-section {
  background: #060810;
  border-top: 1px solid var(--border);
  padding: 48px 24px;
  color: var(--text-secondary);
}

.seo-container {
  max-width: 1200px;
  margin: 0 auto;
}

.seo-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
  gap: 24px;
  margin-bottom: 48px;
}

.seo-card {
  background: #090d18;
  border: 1px solid rgba(255, 255, 255, 0.06);
  border-radius: 12px;
  padding: 24px;
  box-shadow: 0 4px 16px rgba(0, 0, 0, 0.2);
}

.seo-card-header {
  display: flex;
  align-items: center;
  gap: 10px;
  margin-bottom: 12px;
}

.seo-card-header h3 {
  font: 700 15px var(--font-sans);
  color: var(--text-primary);
  margin: 0;
}

.seo-card p {
  font: 400 13.5px/1.6 var(--font-sans);
  color: #94a3b8;
  margin: 0;
}

.seo-faq-section {
  border-top: 1px solid rgba(255, 255, 255, 0.08);
  padding-top: 36px;
}

.seo-faq-title {
  font: 800 20px var(--font-sans);
  color: var(--text-primary);
  margin: 0 0 24px 0;
  text-align: center;
}

.seo-faq-list {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(320px, 1fr));
  gap: 20px;
}

.seo-faq-item {
  background: #090d18;
  border: 1px solid rgba(255, 255, 255, 0.05);
  border-radius: 10px;
  padding: 20px;
}

.seo-faq-item h4 {
  font: 600 14px var(--font-sans);
  color: #38bdf8;
  margin: 0 0 8px 0;
}

.seo-faq-item p {
  font: 400 13px/1.6 var(--font-sans);
  color: #cbd5e1;
  margin: 0;
}

/* Site Footer */
.site-footer {
  background: #04060b;
  border-top: 1px solid rgba(255, 255, 255, 0.08);
  padding: 48px 24px 24px 24px;
  color: #94a3b8;
  font-family: var(--font-sans);
}

.footer-container {
  max-width: 1200px;
  margin: 0 auto;
}

.footer-top {
  display: grid;
  grid-template-columns: 2fr 1fr 1fr 1.2fr;
  gap: 36px;
  padding-bottom: 36px;
  border-bottom: 1px solid rgba(255, 255, 255, 0.06);
}

@media (max-width: 768px) {
  .footer-top {
    grid-template-columns: 1fr;
    gap: 24px;
  }
}

.footer-brand {
  display: flex;
  flex-direction: column;
  gap: 12px;
}

.footer-logo {
  display: flex;
  align-items: center;
  gap: 8px;
  font: 800 18px var(--font-sans);
  color: #fff;
  letter-spacing: -0.02em;
}

.footer-desc {
  font: 400 13px/1.6 var(--font-sans);
  color: #94a3b8;
  margin: 0;
  max-width: 340px;
}

.footer-meta {
  font: 500 11.5px var(--font-mono);
  color: var(--text-muted);
}

.footer-links-group h4 {
  font: 700 13px var(--font-sans);
  color: #f1f5f9;
  text-transform: uppercase;
  letter-spacing: 0.05em;
  margin: 0 0 14px 0;
}

.footer-links-group ul {
  list-style: none;
  padding: 0;
  margin: 0;
  display: flex;
  flex-direction: column;
  gap: 9px;
}

.footer-links-group a {
  color: #94a3b8;
  text-decoration: none;
  font-size: 13px;
  transition: color 0.15s;
}
.footer-links-group a:hover {
  color: #38bdf8;
}

.footer-bottom {
  display: flex;
  align-items: center;
  justify-content: space-between;
  flex-wrap: wrap;
  gap: 16px;
  padding-top: 24px;
  font-size: 12px;
  color: #64748b;
}

.footer-copyright {
  color: #64748b;
}

.footer-legal-inline {
  display: flex;
  align-items: center;
  gap: 8px;
}

.footer-legal-inline a {
  color: #94a3b8;
  text-decoration: none;
  transition: color 0.15s;
}
.footer-legal-inline a:hover {
  color: #38bdf8;
  text-decoration: underline;
}