/* =============================================
   GlanceSQL — Custom Styles
   Dark-by-default professional theme
   ============================================= */

/* ─── Inter + JetBrains Mono ─── */
@import url('https://fonts.googleapis.com/css2?family=Inter:wght@400;500;600;700&family=JetBrains+Mono:wght@400;500;600&display=swap');

/* ─── Theme Variables ─── */
:root {
  --font-sans: 'Inter', system-ui, -apple-system, sans-serif;
  --font-mono: 'JetBrains Mono', 'Fira Code', 'Consolas', monospace;

  --sidebar-w: 280px;
  --header-h: 56px;
  --radius: 10px;
  --radius-sm: 6px;

  --transition: 200ms cubic-bezier(0.4, 0, 0.2, 1);
}

/* Light (default) */
:root {
  --bg-base: #f8fafc;
  --bg-surface: #ffffff;
  --bg-sidebar: #f1f5f9;
  --bg-elevated: #ffffff;
  --bg-hover: #e2e8f0;
  --bg-active: #dbeafe;

  --text-primary: #0f172a;
  --text-secondary: #475569;
  --text-tertiary: #94a3b8;
  --text-inverse: #ffffff;

  --border: #e2e8f0;
  --border-accent: #bfdbfe;

  --accent: #3b82f6;
  --accent-soft: #eff6ff;
  --accent-ring: #93c5fd;
  --green: #10b981;
  --green-soft: #ecfdf5;
  --amber: #f59e0b;
  --rose: #f43f5e;

  --syntax-keyword: #7c3aed;
  --syntax-function: #2563eb;
  --syntax-string: #059669;
  --syntax-number: #d97706;
  --syntax-comment: #94a3b8;

  --scrollbar-thumb: #cbd5e1;
  --scrollbar-track: transparent;
}

/* Dark */
.dark {
  --bg-base: #0b1120;
  --bg-surface: #131c31;
  --bg-sidebar: #0f172a;
  --bg-elevated: #1a2744;
  --bg-hover: #1e293b;
  --bg-active: #1e3a5f;

  --text-primary: #f1f5f9;
  --text-secondary: #94a3b8;
  --text-tertiary: #64748b;
  --text-inverse: #0f172a;

  --border: #1e293b;
  --border-accent: #1e3a5f;

  --accent: #60a5fa;
  --accent-soft: #172554;
  --accent-ring: #3b82f6;
  --green: #34d399;
  --green-soft: #064e3b;
  --amber: #fbbf24;
  --rose: #fb7185;

  --syntax-keyword: #a78bfa;
  --syntax-function: #93c5fd;
  --syntax-string: #34d399;
  --syntax-number: #fbbf24;
  --syntax-comment: #64748b;

  --scrollbar-thumb: #334155;
  --scrollbar-track: transparent;
}

/* ─── Base Reset ─── */
*, *::before, *::after {
  box-sizing: border-box;
}

html {
  font-family: var(--font-sans);
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
}

/* Safe area insets for notched phones */
@supports (padding: env(safe-area-inset-top)) {
  .safe-area-pt { padding-top: env(safe-area-inset-top); }
  .safe-area-pb { padding-bottom: env(safe-area-inset-bottom); }
  .safe-area-pl { padding-left: env(safe-area-inset-left); }
  .safe-area-pr { padding-right: env(safe-area-inset-right); }
}

body {
  margin: 0;
  background: var(--bg-base);
  color: var(--text-primary);
  line-height: 1.6;
  -webkit-tap-highlight-color: transparent;
  overscroll-behavior: none;
}

/* Better touch targets */
button, a, .topic-item, .step-item {
  touch-action: manipulation;
}

/* ─── Scrollbar ─── */
::-webkit-scrollbar { width: 6px; height: 6px; }
::-webkit-scrollbar-track { background: var(--scrollbar-track); }
::-webkit-scrollbar-thumb {
  background: var(--scrollbar-thumb);
  border-radius: 3px;
}
::-webkit-scrollbar-thumb:hover { background: var(--text-tertiary); }

/* Firefox */
* { scrollbar-width: thin; scrollbar-color: var(--scrollbar-thumb) var(--scrollbar-track); }

/* ─── Sidebar ─── */
.sidebar {
  position: fixed;
  top: var(--header-h);
  left: 0;
  width: var(--sidebar-w);
  height: calc(100vh - var(--header-h));
  height: calc(100dvh - var(--header-h));
  background: var(--bg-sidebar);
  border-right: 1px solid var(--border);
  overflow-y: auto;
  overscroll-behavior: contain;
  z-index: 40;
  transition: transform var(--transition);
}

.sidebar.closed {
  transform: translateX(-100%);
}

@media (max-width: 768px) {
  .sidebar {
    width: 85vw;
    max-width: 320px;
    transform: translateX(-100%);
  }
  .sidebar.open {
    transform: translateX(0);
  }
}

/* ─── Topic Items ─── */
.topic-item {
  display: flex;
  align-items: center;
  gap: 10px;
  padding: 8px 14px;
  border-radius: var(--radius-sm);
  color: var(--text-secondary);
  cursor: pointer;
  transition: all var(--transition);
  font-size: 0.875rem;
  line-height: 1.4;
  text-decoration: none;
  user-select: none;
}

@media (max-width: 640px) {
  .topic-item {
    padding: 12px 14px;
  }
}

.topic-item:hover {
  background: var(--bg-hover);
  color: var(--text-primary);
}

.topic-item.active {
  background: var(--bg-active);
  color: var(--accent);
  font-weight: 500;
}

.topic-item .check {
  width: 16px;
  height: 16px;
  flex-shrink: 0;
  border-radius: 50%;
  border: 2px solid var(--border);
  display: inline-flex;
  align-items: center;
  justify-content: center;
  transition: all var(--transition);
}

.topic-item .check.done {
  background: var(--green);
  border-color: var(--green);
}

.topic-item .check.done::after {
  content: '';
  width: 5px;
  height: 8px;
  border: solid white;
  border-width: 0 2px 2px 0;
  transform: rotate(45deg) translateY(-1px);
}

.topic-item .icon {
  flex-shrink: 0;
  font-size: 1rem;
  width: 20px;
  text-align: center;
}

/* ─── Category Group ─── */
.cat-header {
  padding: 16px 14px 6px;
  font-size: 0.7rem;
  font-weight: 600;
  text-transform: uppercase;
  letter-spacing: 0.08em;
  color: var(--text-tertiary);
}

/* ─── Difficulty Badge ─── */
.badge {
  display: inline-flex;
  align-items: center;
  padding: 2px 8px;
  border-radius: 999px;
  font-size: 0.65rem;
  font-weight: 600;
  text-transform: uppercase;
  letter-spacing: 0.04em;
  line-height: 1.4;
}

.badge-beginner { background: var(--green-soft); color: var(--green); }
.badge-intermediate { background: var(--accent-soft); color: var(--accent); }
.badge-advanced { background: #fff7ed; color: var(--amber); }
.dark .badge-advanced { background: #422006; color: var(--amber); }
.badge-expert { background: #fef2f2; color: var(--rose); }
.dark .badge-expert { background: #4c0519; color: var(--rose); }

/* ─── Content Card ─── */
.card {
  background: var(--bg-surface);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 24px;
  transition: background var(--transition), border-color var(--transition);
}

@media (max-width: 640px) {
  .card {
    padding: 16px;
  }
}

.card-header {
  font-size: 1rem;
  font-weight: 600;
  margin-bottom: 12px;
  display: flex;
  align-items: center;
  gap: 8px;
}

/* ─── Code Block ─── */
.code-block {
  background: #0d1117 !important;
  border: 1px solid #21262d;
  border-radius: var(--radius-sm);
  font-family: var(--font-mono);
  font-size: 0.8125rem;
  line-height: 1.6;
  overflow-x: auto;
  padding: 16px 20px;
  margin: 12px 0;
  tab-size: 2;
}

/* ─── Inline Code ─── */
code:not([class*="language"]) {
  background: var(--bg-hover);
  padding: 2px 6px;
  border-radius: 4px;
  font-family: var(--font-mono);
  font-size: 0.85em;
  color: var(--accent);
}

/* ─── Prism Overrides ─── */
code[class*="language-"],
pre[class*="language-"] {
  font-family: var(--font-mono) !important;
  font-size: 0.8125rem !important;
  line-height: 1.6 !important;
  text-shadow: none !important;
  direction: ltr;
  white-space: pre;
  word-spacing: normal;
  word-break: normal;
  tab-size: 2;
}

:not(pre) > code[class*="language-"],
pre[class*="language-"] {
  background: #0d1117 !important;
  border-radius: var(--radius-sm);
}

.token.keyword { color: var(--syntax-keyword) !important; }
.token.function { color: var(--syntax-function) !important; }
.token.string { color: var(--syntax-string) !important; }
.token.number { color: var(--syntax-number) !important; }
.token.comment { color: var(--syntax-comment) !important; font-style: italic; }
.token.operator { color: var(--syntax-keyword) !important; }
.token.punctuation { color: var(--text-secondary) !important; }

/* ─── Interactives ─── */
.table-wrap {
  overflow-x: auto;
  -webkit-overflow-scrolling: touch;
  max-width: 100%;
}

.demo-table {
  width: 100%;
  min-width: 0;
  border-collapse: collapse;
  font-size: 0.8125rem;
  font-family: var(--font-mono);
}

.demo-table th {
  text-align: left;
  padding: 8px 12px;
  background: var(--bg-hover);
  font-weight: 600;
  font-size: 0.75rem;
  text-transform: uppercase;
  letter-spacing: 0.05em;
  color: var(--text-secondary);
  border-bottom: 2px solid var(--border);
}

.demo-table td {
  padding: 8px 12px;
  border-bottom: 1px solid var(--border);
  color: var(--text-primary);
  word-break: break-word;
  max-width: 200px;
}

@media (max-width: 640px) {
  .demo-table td,
  .demo-table th {
    padding: 6px 8px;
    font-size: 0.75rem;
  }
}

.demo-table tr:hover td {
  background: var(--bg-hover);
}

.demo-table tr.highlight td {
  background: var(--accent-soft);
  border-color: var(--border-accent);
}

.demo-table tr.dim td {
  opacity: 0.3;
}

.visual-step {
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 16px;
  padding: 20px;
  background: var(--bg-elevated);
  border-radius: var(--radius-sm);
  border: 1px dashed var(--border);
  font-size: 0.875rem;
  color: var(--text-secondary);
}

/* ─── Step Walkthrough ─── */
.step-list {
  counter-reset: step;
}

.step-item {
  display: flex;
  gap: 16px;
  padding: 16px 0;
  border-bottom: 1px solid var(--border);
  counter-increment: step;
}

.step-item:last-child {
  border-bottom: none;
}

.step-number {
  flex-shrink: 0;
  width: 28px;
  height: 28px;
  border-radius: 50%;
  background: var(--accent-soft);
  color: var(--accent);
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 0.75rem;
  font-weight: 700;
}

.step-item.active .step-number {
  background: var(--accent);
  color: white;
}

/* ─── Search ─── */
.search-input {
  width: 100%;
  padding: 10px 14px;
  background: var(--bg-surface);
  border: 1px solid var(--border);
  border-radius: var(--radius-sm);
  color: var(--text-primary);
  font-family: var(--font-sans);
  font-size: 0.8125rem;
  outline: none;
  transition: border-color var(--transition), box-shadow var(--transition);
}

.search-input::placeholder {
  color: var(--text-tertiary);
}

.search-input:focus {
  border-color: var(--accent-ring);
  box-shadow: 0 0 0 3px var(--accent-soft);
}

/* ─── Animations ─── */
@keyframes fadeIn {
  from { opacity: 0; transform: translateY(8px); }
  to   { opacity: 1; transform: translateY(0); }
}

@keyframes slideIn {
  from { opacity: 0; transform: translateX(-12px); }
  to   { opacity: 1; transform: translateX(0); }
}

@keyframes pulse-dot {
  0%, 100% { opacity: 1; }
  50%      { opacity: 0.4; }
}

.animate-fade-in {
  animation: fadeIn 0.3s ease-out both;
}

.animate-slide-in {
  animation: slideIn 0.25s ease-out both;
}

/* ─── Section stagger ─── */
.section-enter {
  animation: fadeIn 0.35s ease-out both;
}

.section-enter:nth-child(1) { animation-delay: 0.02s; }
.section-enter:nth-child(2) { animation-delay: 0.06s; }
.section-enter:nth-child(3) { animation-delay: 0.10s; }
.section-enter:nth-child(4) { animation-delay: 0.14s; }
.section-enter:nth-child(5) { animation-delay: 0.18s; }
.section-enter:nth-child(6) { animation-delay: 0.22s; }
.section-enter:nth-child(7) { animation-delay: 0.26s; }
.section-enter:nth-child(8) { animation-delay: 0.30s; }

/* ─── Loading Skeleton ─── */
.skeleton {
  background: linear-gradient(90deg,
    var(--bg-hover) 25%,
    var(--bg-surface) 50%,
    var(--bg-hover) 75%
  );
  background-size: 200% 100%;
  animation: shimmer 1.5s ease-in-out infinite;
  border-radius: var(--radius-sm);
}

@keyframes shimmer {
  0%   { background-position: 200% 0; }
  100% { background-position: -200% 0; }
}

/* ─── Theme Toggle ─── */
.theme-btn {
  width: 36px;
  height: 36px;
  border-radius: 50%;
  border: 1px solid var(--border);
  background: var(--bg-surface);
  color: var(--text-secondary);
  cursor: pointer;
  display: flex;
  align-items: center;
  justify-content: center;
  transition: all var(--transition);
  font-size: 1rem;
}

.theme-btn:hover {
  background: var(--bg-hover);
  color: var(--text-primary);
  border-color: var(--text-tertiary);
}

@media (max-width: 640px) {
  .theme-btn {
    width: 44px;
    height: 44px;
  }
}

/* ─── Utility ─── */
.truncate {
  overflow: hidden;
  text-overflow: ellipsis;
  white-space: nowrap;
}

.flex-center {
  display: flex;
  align-items: center;
  justify-content: center;
}

.empty-state {
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  padding: 60px 20px;
  text-align: center;
  color: var(--text-tertiary);
  gap: 12px;
}

.empty-state svg {
  width: 64px;
  height: 64px;
  opacity: 0.4;
}

/* ─── Keyboard shortcut hint ─── */
kbd {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  padding: 2px 6px;
  font-size: 0.7rem;
  font-family: var(--font-mono);
  font-weight: 500;
  color: var(--text-tertiary);
  background: var(--bg-hover);
  border: 1px solid var(--border);
  border-radius: 4px;
  min-width: 20px;
}

/* ─── Main content sidebar-aware padding ─── */
@media (min-width: 769px) {
  .sidebar-open {
    padding-left: var(--sidebar-w) !important;
  }
}

/* ─── Responsive overlay ─── */
.sidebar-overlay {
  position: fixed;
  inset: 0;
  background: rgba(0,0,0,0.4);
  z-index: 35;
  opacity: 0;
  pointer-events: none;
  transition: opacity var(--transition);
}

.sidebar-overlay.show {
  opacity: 1;
  pointer-events: auto;
}

/* ─── Transition groups ─── */
.fade-enter { opacity: 0; }
.fade-enter-active { opacity: 1; transition: opacity 0.2s; }
.fade-leave { opacity: 1; }
.fade-leave-active { opacity: 0; transition: opacity 0.2s; }