/* =========================================================
   Angular Interview Prep - Dark Mode Design System
   ========================================================= */

:root {
  --bg-base:       #0d1117;
  --bg-surface:    #161b22;
  --bg-elevated:   #1c2128;
  --bg-hover:      #21262d;
  --border:        #30363d;
  --border-light:  #21262d;
  --text-primary:  #e6edf3;
  --text-secondary:#8b949e;
  --text-muted:    #6e7681;
  --accent:        #58a6ff;
  --accent-dim:    #1f3d5c;
  --success:       #3fb950;
  --success-dim:   #1a3326;
  --error:         #f85149;
  --error-dim:     #3d1a1a;
  --warning:       #d29922;
  --warning-dim:   #3d2e00;
  --purple:        #bc8cff;
  --purple-dim:    #2d1f4a;
  --teal:          #39d353;
  --orange:        #f0883e;
  --orange-dim:    #3d2200;
  --pink:          #ff7b72;

  /* Category colours */
  --cat-architecture: #58a6ff;
  --cat-angular:      #dd6b20;
  --cat-rxjs:         #bc8cff;
  --cat-forms:        #3fb950;
  --cat-performance:  #f0883e;
  --cat-css:          #ff7b72;
  --cat-pwa:          #39d353;
  --cat-testing:      #d29922;
  --cat-devops:       #58a6ff;
  --cat-camunda:      #bc8cff;
  --cat-domain:       #f0883e;
  --cat-ai-tools:     #ff7b72;
  --cat-cloud:        #39d353;
  --cat-typescript:   #58a6ff;
  --cat-behavioral:   #8b949e;
  --cat-system-design:#d29922;

  --radius-sm: 6px;
  --radius:    10px;
  --radius-lg: 14px;
  --shadow:    0 4px 24px rgba(0,0,0,.4);
  --transition: .18s ease;
}

*, *::before, *::after { box-sizing: border-box; margin: 0; padding: 0; }

html { scroll-behavior: smooth; font-size: 16px; }

body {
  font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, Helvetica, Arial, sans-serif;
  background: var(--bg-base);
  color: var(--text-primary);
  line-height: 1.6;
  min-height: 100vh;
}

/* ── Scrollbar ─────────────────────────────────────────── */
::-webkit-scrollbar { width: 6px; }
::-webkit-scrollbar-track { background: var(--bg-base); }
::-webkit-scrollbar-thumb { background: var(--border); border-radius: 3px; }

/* ── Typography ────────────────────────────────────────── */
h1 { font-size: clamp(1.4rem, 4vw, 2rem); font-weight: 700; }
h2 { font-size: clamp(1.1rem, 3vw, 1.4rem); font-weight: 600; }
h3 { font-size: 1rem; font-weight: 600; }
p  { color: var(--text-secondary); }

code, pre {
  font-family: 'Courier New', 'Fira Code', monospace;
  font-size: .85em;
  background: var(--bg-elevated);
  border-radius: var(--radius-sm);
  padding: .15em .4em;
  color: var(--orange);
}

/* ── Header ────────────────────────────────────────────── */
.header {
  position: sticky;
  top: 0;
  z-index: 100;
  background: rgba(13,17,23,.92);
  backdrop-filter: blur(12px);
  border-bottom: 1px solid var(--border);
  padding: 0 1rem;
}

.header-inner {
  max-width: 1100px;
  margin: 0 auto;
  display: flex;
  align-items: center;
  gap: .75rem;
  height: 56px;
  flex-wrap: nowrap;
}

.logo {
  display: flex;
  align-items: center;
  gap: .5rem;
  text-decoration: none;
  color: var(--text-primary);
  font-weight: 700;
  font-size: 1rem;
  white-space: nowrap;
  flex-shrink: 0;
}

.logo-icon {
  width: 32px; height: 32px;
  background: linear-gradient(135deg, var(--accent), var(--purple));
  border-radius: 8px;
  position: relative;
  overflow: hidden;
  font-size: 0;
  color: transparent;
}

.logo-icon::before {
  content: "";
  position: absolute;
  inset: 3px;
  background: url('./logo-capybara.svg') center / contain no-repeat;
}

.nav {
  display: flex;
  gap: .25rem;
  flex: 1;
}

.nav-link {
  text-decoration: none;
  color: var(--text-secondary);
  padding: .35rem .65rem;
  border-radius: var(--radius-sm);
  font-size: .875rem;
  font-weight: 500;
  transition: color var(--transition), background var(--transition);
  white-space: nowrap;
}

.nav-link:hover { color: var(--text-primary); background: var(--bg-hover); }
.nav-link.active { color: var(--accent); background: var(--accent-dim); }

.header-actions {
  display: flex;
  align-items: center;
  gap: .5rem;
  flex-shrink: 0;
}

/* ── Language Toggle ────────────────────────────────────── */
.lang-toggle {
  display: flex;
  background: var(--bg-elevated);
  border: 1px solid var(--border);
  border-radius: var(--radius-sm);
  overflow: hidden;
}

.lang-btn {
  padding: .3rem .55rem;
  border: none;
  background: none;
  color: var(--text-secondary);
  font-size: .8rem;
  font-weight: 600;
  cursor: pointer;
  transition: background var(--transition), color var(--transition);
}

.lang-btn.active {
  background: var(--accent);
  color: #fff;
}

/* ── Main Layout ────────────────────────────────────────── */
.main {
  max-width: 1100px;
  margin: 0 auto;
  padding: 1.5rem 1rem 3rem;
}

/* ── Hero ───────────────────────────────────────────────── */
.hero {
  text-align: center;
  padding: 2rem 1rem 1.5rem;
  border-bottom: 1px solid var(--border-light);
  margin-bottom: 1.5rem;
}

.hero-subtitle {
  margin: .5rem auto 0;
  max-width: 560px;
  font-size: .9rem;
  color: var(--text-secondary);
}

.badge-row {
  display: flex;
  flex-wrap: wrap;
  gap: .4rem;
  justify-content: center;
  margin-top: 1rem;
}

.badge {
  display: inline-flex;
  align-items: center;
  gap: .3rem;
  padding: .2rem .6rem;
  border-radius: 999px;
  font-size: .75rem;
  font-weight: 600;
  border: 1px solid;
}

/* ── Search ─────────────────────────────────────────────── */
.search-bar {
  position: relative;
  margin-bottom: 1rem;
}

.search-bar input {
  width: 100%;
  background: var(--bg-surface);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: .65rem 1rem .65rem 2.4rem;
  color: var(--text-primary);
  font-size: .9rem;
  outline: none;
  transition: border-color var(--transition);
}

.search-bar input:focus { border-color: var(--accent); }
.search-bar input::placeholder { color: var(--text-muted); }

.search-icon {
  position: absolute;
  left: .8rem;
  top: 50%;
  transform: translateY(-50%);
  color: var(--text-muted);
  pointer-events: none;
}

/* ── Category Filters ───────────────────────────────────── */
.cat-filters {
  display: flex;
  gap: .4rem;
  flex-wrap: wrap;
  margin-bottom: 1.25rem;
}

.cat-btn {
  padding: .3rem .7rem;
  border: 1px solid var(--border);
  border-radius: 999px;
  background: none;
  color: var(--text-secondary);
  font-size: .8rem;
  font-weight: 500;
  cursor: pointer;
  transition: all var(--transition);
  white-space: nowrap;
}

.cat-btn:hover { border-color: var(--accent); color: var(--accent); }
.cat-btn.active { background: var(--accent); border-color: var(--accent); color: #fff; }

/* ── Category Section ───────────────────────────────────── */
.category-section {
  margin-bottom: 1.5rem;
}

.category-header {
  display: flex;
  align-items: center;
  gap: .6rem;
  margin-bottom: .75rem;
  padding-bottom: .5rem;
  border-bottom: 1px solid var(--border-light);
}

.category-dot {
  width: 10px; height: 10px;
  border-radius: 50%;
  flex-shrink: 0;
}

.category-title {
  font-size: .85rem;
  font-weight: 700;
  text-transform: uppercase;
  letter-spacing: .06em;
  color: var(--text-muted);
}

.category-count {
  margin-left: auto;
  font-size: .75rem;
  color: var(--text-muted);
  background: var(--bg-elevated);
  padding: .1rem .45rem;
  border-radius: 999px;
}

/* ── Topic Card ─────────────────────────────────────────── */
.topic-card {
  background: var(--bg-surface);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  margin-bottom: .5rem;
  overflow: hidden;
  transition: border-color var(--transition);
}

.topic-card:hover { border-color: var(--border); }
.topic-card.open { border-color: var(--accent); }

.topic-header {
  display: flex;
  align-items: center;
  gap: .75rem;
  padding: .85rem 1rem;
  cursor: pointer;
  user-select: none;
  transition: background var(--transition);
}

.topic-header:hover { background: var(--bg-hover); }

.topic-number {
  font-size: .7rem;
  font-weight: 700;
  color: var(--text-muted);
  background: var(--bg-elevated);
  width: 24px; height: 24px;
  border-radius: 4px;
  display: flex; align-items: center; justify-content: center;
  flex-shrink: 0;
}

.topic-name { font-weight: 600; font-size: .95rem; flex: 1; }

.topic-tags {
  display: flex;
  gap: .3rem;
}

.topic-tag {
  font-size: .65rem;
  font-weight: 600;
  padding: .15rem .4rem;
  border-radius: 4px;
  background: var(--bg-elevated);
  color: var(--text-muted);
}

.topic-chevron {
  color: var(--text-muted);
  transition: transform var(--transition);
  flex-shrink: 0;
}

.topic-card.open .topic-chevron { transform: rotate(180deg); }

.topic-body {
  display: none;
  padding: 0 1rem 1rem;
  border-top: 1px solid var(--border-light);
}

.topic-card.open .topic-body { display: block; }

.topic-definition {
  margin-top: .75rem;
  font-size: .9rem;
  color: var(--text-primary);
  line-height: 1.65;
}

.topic-section-label {
  font-size: .7rem;
  font-weight: 700;
  text-transform: uppercase;
  letter-spacing: .07em;
  color: var(--text-muted);
  margin: 1rem 0 .4rem;
}

.topic-bullets {
  list-style: none;
  display: flex;
  flex-direction: column;
  gap: .35rem;
}

.topic-bullets li {
  font-size: .875rem;
  color: var(--text-secondary);
  padding-left: 1.1rem;
  position: relative;
}

.topic-bullets li::before {
  content: '▸';
  position: absolute;
  left: 0;
  color: var(--accent);
}

.topic-example {
  background: var(--bg-elevated);
  border: 1px solid var(--border-light);
  border-left: 3px solid var(--accent);
  border-radius: var(--radius-sm);
  padding: .65rem .85rem;
  font-size: .825rem;
  color: var(--text-secondary);
  margin-top: .5rem;
  line-height: 1.6;
}

.topic-keywords {
  display: flex;
  flex-wrap: wrap;
  gap: .3rem;
  margin-top: .75rem;
}

.keyword {
  font-size: .72rem;
  font-weight: 500;
  padding: .15rem .5rem;
  border-radius: 999px;
  border: 1px solid var(--border);
  color: var(--accent);
  background: var(--accent-dim);
}

/* ── Quiz Page ──────────────────────────────────────────── */
.quiz-start {
  text-align: center;
  max-width: 480px;
  margin: 3rem auto;
}

.quiz-start h2 { margin-bottom: .5rem; }
.quiz-start p { margin-bottom: 1.5rem; }

.count-options {
  display: flex;
  gap: .75rem;
  justify-content: center;
  flex-wrap: wrap;
  margin-bottom: 1.5rem;
}

.count-btn {
  width: 100px; height: 100px;
  border-radius: var(--radius);
  border: 2px solid var(--border);
  background: var(--bg-surface);
  cursor: pointer;
  display: flex; flex-direction: column;
  align-items: center; justify-content: center;
  gap: .25rem;
  transition: all var(--transition);
  color: var(--text-primary);
}

.count-btn:hover { border-color: var(--accent); background: var(--accent-dim); }
.count-btn.selected { border-color: var(--accent); background: var(--accent-dim); }
.count-btn .count-num { font-size: 2rem; font-weight: 800; line-height: 1; }
.count-btn .count-label { font-size: .75rem; color: var(--text-secondary); }

/* ── Quiz Progress ──────────────────────────────────────── */
.quiz-progress-bar {
  background: var(--bg-elevated);
  height: 4px;
  border-radius: 2px;
  margin-bottom: 1.25rem;
  overflow: hidden;
}

.quiz-progress-fill {
  height: 100%;
  background: linear-gradient(90deg, var(--accent), var(--purple));
  border-radius: 2px;
  transition: width .3s ease;
}

.quiz-status {
  display: flex;
  justify-content: space-between;
  font-size: .8rem;
  color: var(--text-secondary);
  margin-bottom: 1rem;
}

/* ── Question Card ──────────────────────────────────────── */
.question-card {
  background: var(--bg-surface);
  border: 1px solid var(--border);
  border-radius: var(--radius-lg);
  padding: 1.25rem;
  margin-bottom: 1rem;
}

.question-type-badge {
  display: inline-block;
  font-size: .7rem;
  font-weight: 700;
  text-transform: uppercase;
  letter-spacing: .06em;
  padding: .2rem .55rem;
  border-radius: 999px;
  background: var(--bg-elevated);
  color: var(--text-muted);
  margin-bottom: .75rem;
}

.question-text {
  font-size: 1rem;
  font-weight: 600;
  color: var(--text-primary);
  line-height: 1.5;
  margin-bottom: 1rem;
}

.answers-grid {
  display: flex;
  flex-direction: column;
  gap: .5rem;
}

.answer-btn {
  display: flex;
  align-items: flex-start;
  gap: .75rem;
  padding: .75rem .9rem;
  border-radius: var(--radius);
  border: 1.5px solid var(--border);
  background: var(--bg-elevated);
  cursor: pointer;
  text-align: left;
  transition: all var(--transition);
  color: var(--text-primary);
  font-size: .875rem;
  line-height: 1.45;
}

.answer-btn:hover:not(:disabled) {
  border-color: var(--accent);
  background: var(--accent-dim);
}

.answer-btn:disabled { cursor: default; }

.answer-marker {
  width: 22px; height: 22px;
  border: 2px solid var(--border);
  border-radius: 50%;
  display: flex; align-items: center; justify-content: center;
  flex-shrink: 0;
  font-size: .75rem;
  font-weight: 700;
  margin-top: .05rem;
  transition: all var(--transition);
}

.answer-btn.multi .answer-marker {
  border-radius: 4px;
}

.answer-btn.selected .answer-marker {
  background: var(--accent);
  border-color: var(--accent);
  color: #fff;
}

.answer-btn.correct {
  border-color: var(--success) !important;
  background: var(--success-dim) !important;
}

.answer-btn.correct .answer-marker {
  background: var(--success);
  border-color: var(--success);
  color: #fff;
}

.answer-btn.wrong {
  border-color: var(--error) !important;
  background: var(--error-dim) !important;
}

.answer-btn.wrong .answer-marker {
  background: var(--error);
  border-color: var(--error);
  color: #fff;
}

.answer-btn.missed {
  border-color: var(--warning) !important;
  background: var(--warning-dim) !important;
}

.answer-text { flex: 1; }

.check-btn {
  width: 100%;
  margin-top: .75rem;
  padding: .65rem;
  border-radius: var(--radius);
  border: none;
  background: var(--accent);
  color: #fff;
  font-size: .9rem;
  font-weight: 600;
  cursor: pointer;
  transition: background var(--transition);
}

.check-btn:hover { background: #79b8ff; }
.check-btn:disabled { background: var(--bg-elevated); color: var(--text-muted); cursor: default; }

.explanation-box {
  margin-top: .75rem;
  padding: .7rem .9rem;
  border-radius: var(--radius-sm);
  background: var(--bg-elevated);
  border-left: 3px solid var(--accent);
  font-size: .825rem;
  color: var(--text-secondary);
  display: none;
}

.explanation-box.show { display: block; }

.next-btn {
  width: 100%;
  margin-top: .75rem;
  padding: .65rem;
  border-radius: var(--radius);
  border: 1px solid var(--border);
  background: var(--bg-elevated);
  color: var(--text-primary);
  font-size: .9rem;
  font-weight: 600;
  cursor: pointer;
  transition: all var(--transition);
  display: none;
}

.next-btn.show { display: block; }
.next-btn:hover { background: var(--bg-hover); border-color: var(--accent); color: var(--accent); }

/* ── Results ────────────────────────────────────────────── */
.results-card {
  text-align: center;
  padding: 2rem 1rem;
  background: var(--bg-surface);
  border: 1px solid var(--border);
  border-radius: var(--radius-lg);
  margin-top: 1.5rem;
}

.score-circle {
  width: 120px; height: 120px;
  border-radius: 50%;
  border: 4px solid;
  display: flex; flex-direction: column;
  align-items: center; justify-content: center;
  margin: 0 auto 1.25rem;
  position: relative;
}

.score-pct {
  font-size: 2rem;
  font-weight: 800;
  line-height: 1;
}

.score-label {
  font-size: .7rem;
  color: var(--text-secondary);
  text-transform: uppercase;
  letter-spacing: .06em;
}

.results-details {
  display: flex;
  justify-content: center;
  gap: 1.5rem;
  margin-bottom: 1.25rem;
  flex-wrap: wrap;
}

.result-stat { text-align: center; }
.result-stat-num { font-size: 1.5rem; font-weight: 700; display: block; }
.result-stat-label { font-size: .75rem; color: var(--text-secondary); }

.results-actions {
  display: flex;
  gap: .75rem;
  justify-content: center;
  flex-wrap: wrap;
  margin-bottom: 1.5rem;
}

.btn {
  display: inline-flex;
  align-items: center;
  gap: .4rem;
  padding: .6rem 1.1rem;
  border-radius: var(--radius);
  font-size: .875rem;
  font-weight: 600;
  cursor: pointer;
  border: none;
  transition: all var(--transition);
  text-decoration: none;
}

.btn-primary { background: var(--accent); color: #fff; }
.btn-primary:hover { background: #79b8ff; }
.btn-secondary { background: var(--bg-elevated); color: var(--text-primary); border: 1px solid var(--border); }
.btn-secondary:hover { background: var(--bg-hover); border-color: var(--accent); }
.btn-success { background: var(--success-dim); color: var(--success); border: 1px solid var(--success); }
.btn-success:hover { background: var(--success); color: #fff; }

/* Wrong topics list */
.wrong-topics {
  text-align: left;
  margin-top: 1rem;
}

.wrong-topic-item {
  background: var(--bg-elevated);
  border: 1px solid var(--border);
  border-left: 3px solid var(--error);
  border-radius: var(--radius-sm);
  padding: .6rem .85rem;
  margin-bottom: .4rem;
  font-size: .85rem;
}

.wrong-topic-name { font-weight: 600; color: var(--text-primary); }
.wrong-topic-hint { font-size: .78rem; color: var(--text-secondary); margin-top: .2rem; }

/* ── Utility ────────────────────────────────────────────── */
.hidden { display: none !important; }
.text-center { text-align: center; }

.section-divider {
  border: none;
  border-top: 1px solid var(--border-light);
  margin: 1.25rem 0;
}

/* ── Empty state ────────────────────────────────────────── */
.empty-state {
  text-align: center;
  padding: 3rem 1rem;
  color: var(--text-muted);
}

.empty-state svg { margin-bottom: .75rem; opacity: .4; }

/* ── Responsive adjustments for iPhone 13 mini (375px) ─── */
@media (max-width: 390px) {
  .header-inner { gap: .4rem; }
  .logo span { display: none; }
  .nav-link { padding: .3rem .5rem; font-size: .8rem; }
  .count-btn { width: 85px; height: 85px; }
  .count-btn .count-num { font-size: 1.75rem; }
  .topic-tags { display: none; }
  .results-details { gap: 1rem; }
}

@media (min-width: 768px) {
  .answers-grid { display: grid; grid-template-columns: 1fr 1fr; }
}

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

.topic-card, .question-card, .results-card {
  animation: fadeIn .2s ease;
}

/* ── Stats row at top of definitions ────────────────────── */
.stats-row {
  display: flex;
  gap: .75rem;
  margin-bottom: 1.25rem;
  flex-wrap: wrap;
}

.stat-chip {
  display: flex;
  align-items: center;
  gap: .4rem;
  background: var(--bg-surface);
  border: 1px solid var(--border);
  border-radius: var(--radius-sm);
  padding: .4rem .75rem;
  font-size: .8rem;
  color: var(--text-secondary);
}

.stat-chip strong { color: var(--text-primary); }

/* ── Mock interview specifics ───────────────────────────── */
.mock-meta {
  display: flex;
  gap: .5rem;
  flex-wrap: wrap;
  margin-bottom: .75rem;
}

.mock-timer {
  font-variant-numeric: tabular-nums;
  font-weight: 700;
  color: var(--text-primary);
}

.mock-timer.warn { color: var(--warning); }
.mock-timer.over { color: var(--error); }

.mock-textarea {
  width: 100%;
  min-height: 140px;
  background: var(--bg-elevated);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: .75rem .9rem;
  color: var(--text-primary);
  font-family: inherit;
  font-size: .9rem;
  line-height: 1.55;
  outline: none;
  resize: vertical;
  transition: border-color var(--transition);
}

.mock-textarea:focus { border-color: var(--accent); }

.time-up-banner {
  margin-top: .75rem;
  padding: .6rem .9rem;
  background: var(--warning-dim);
  border: 1px solid var(--warning);
  border-left: 3px solid var(--warning);
  border-radius: var(--radius-sm);
  color: var(--warning);
  font-size: .85rem;
  font-weight: 600;
}

.model-answer {
  margin-top: 1rem;
  padding-top: 1rem;
  border-top: 1px solid var(--border-light);
}

.model-answer-text {
  background: var(--bg-elevated);
  border: 1px solid var(--border-light);
  border-left: 3px solid var(--accent);
  border-radius: var(--radius-sm);
  padding: .75rem .9rem;
  font-size: .9rem;
  color: var(--text-primary);
  line-height: 1.65;
  white-space: pre-line;
}

.rate-buttons {
  display: flex;
  gap: .5rem;
  flex-wrap: wrap;
}

.rate-btn {
  flex: 1;
  min-width: 120px;
  justify-content: center;
}

.rate-btn.selected {
  outline: 2px solid var(--accent);
  outline-offset: 2px;
}

@media (max-width: 390px) {
  .rate-btn { min-width: 0; }
}

/* ── Home page (index.html) ───────────────────────────── */
.home-cards {
  display: grid;
  grid-template-columns: 1fr;
  gap: 1rem;
  margin-top: 2rem;
}

@media (min-width: 768px) {
  .home-cards { grid-template-columns: repeat(3, 1fr); }
}

.home-card {
  --card-color: var(--accent);
  display: flex;
  flex-direction: column;
  gap: .75rem;
  padding: 1.5rem;
  background: var(--bg-surface);
  border: 1px solid var(--border-light);
  border-top: 3px solid var(--card-color);
  border-radius: var(--radius);
  text-decoration: none;
  color: var(--text-primary);
  transition: transform .15s ease, border-color .15s ease, background .15s ease;
}

.home-card:hover,
.home-card:focus-visible {
  background: var(--bg-hover);
  border-color: var(--card-color);
  transform: translateY(-2px);
  outline: none;
}

.home-card-icon {
  width: 44px;
  height: 44px;
  display: grid;
  place-items: center;
  border-radius: 50%;
  background: color-mix(in oklab, var(--card-color) 18%, transparent);
  color: var(--card-color);
}

.home-card h2 {
  margin: 0;
  font-size: 1.25rem;
  color: var(--text-primary);
}

.home-card p {
  margin: 0;
  color: var(--text-secondary);
  line-height: 1.55;
  font-size: .95rem;
  flex: 1;
}

.home-card-cta {
  margin-top: .25rem;
  color: var(--card-color);
  font-weight: 600;
  font-size: .95rem;
}