/* ============================================
   OpenCode 教學網站 — 全域樣式
   ============================================ */

/* --- CSS 變數（主題系統） --- */
:root {
  /* 淺色主題 */
  --bg-primary: #ffffff;
  --bg-secondary: #f8f9fa;
  --bg-tertiary: #e9ecef;
  --text-primary: #1a1a2e;
  --text-secondary: #495057;
  --text-muted: #868e96;
  --accent-primary: #4361ee;
  --accent-secondary: #3a0ca3;
  --accent-gradient: linear-gradient(135deg, #4361ee, #3a0ca3);
  --success: #2ec4b6;
  --warning: #ff9f1c;
  --danger: #e71d36;
  --border-color: #dee2e6;
  --card-bg: #ffffff;
  --card-shadow: 0 2px 8px rgba(0,0,0,0.08);
  --code-bg: #1e1e2e;
  --code-text: #cdd6f4;
  --nav-bg: rgba(255,255,255,0.9);
  --footer-bg: #1a1a2e;
  --footer-text: #e9ecef;
  --tag-beginner: #2ec4b6;
  --tag-intermediate: #ff9f1c;
  --tag-advanced: #e71d36;
}

[data-theme="dark"] {
  --bg-primary: #0f0f23;
  --bg-secondary: #1a1a2e;
  --bg-tertiary: #16213e;
  --text-primary: #e4e4e7;
  --text-secondary: #a1a1aa;
  --text-muted: #71717a;
  --accent-primary: #818cf8;
  --accent-secondary: #6366f1;
  --accent-gradient: linear-gradient(135deg, #818cf8, #6366f1);
  --border-color: #27272a;
  --card-bg: #1a1a2e;
  --card-shadow: 0 2px 8px rgba(0,0,0,0.3);
  --code-bg: #11111b;
  --code-text: #cdd6f4;
  --nav-bg: rgba(15,15,35,0.95);
  --footer-bg: #0a0a1a;
  --footer-text: #a1a1aa;
}

/* --- 基礎重置 --- */
*, *::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, "Noto Sans TC", "PingFang TC", "Microsoft JhengHei", sans-serif;
  background: var(--bg-primary);
  color: var(--text-primary);
  line-height: 1.7;
  transition: background 0.3s, color 0.3s;
  min-height: 100vh;
}

a {
  color: var(--accent-primary);
  text-decoration: none;
  transition: color 0.2s;
}
a:hover {
  color: var(--accent-secondary);
  text-decoration: underline;
}

/* --- 導覽列 --- */
.navbar {
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  z-index: 1000;
  background: var(--nav-bg);
  backdrop-filter: blur(12px);
  border-bottom: 1px solid var(--border-color);
  padding: 0 2rem;
  height: 64px;
  display: flex;
  align-items: center;
  justify-content: space-between;
  transition: background 0.3s;
}

.navbar-brand {
  display: flex;
  align-items: center;
  gap: 0.75rem;
  font-weight: 700;
  font-size: 1.2rem;
  color: var(--text-primary);
  text-decoration: none;
}
.navbar-brand:hover {
  text-decoration: none;
}
.navbar-brand .brand-icon {
  width: 32px;
  height: 32px;
  background: var(--accent-gradient);
  border-radius: 8px;
  display: flex;
  align-items: center;
  justify-content: center;
  color: white;
  font-size: 1rem;
  font-weight: 700;
}

.navbar-links {
  display: flex;
  align-items: center;
  gap: 1rem;
  list-style: none;
}

.navbar-links a {
  color: var(--text-secondary);
  padding: 0.5rem 0.75rem;
  border-radius: 6px;
  font-size: 0.9rem;
  font-weight: 500;
  transition: all 0.2s;
}
.navbar-links a:hover,
.navbar-links a.active {
  background: var(--bg-tertiary);
  color: var(--accent-primary);
  text-decoration: none;
}

.theme-toggle {
  background: none;
  border: 1px solid var(--border-color);
  border-radius: 8px;
  padding: 0.5rem;
  cursor: pointer;
  color: var(--text-primary);
  font-size: 1.1rem;
  display: flex;
  align-items: center;
  justify-content: center;
  transition: all 0.2s;
  width: 40px;
  height: 40px;
}
.theme-toggle:hover {
  background: var(--bg-tertiary);
}

.mobile-menu-btn {
  display: none;
  background: none;
  border: none;
  color: var(--text-primary);
  font-size: 1.5rem;
  cursor: pointer;
  padding: 0.5rem;
}

/* --- 頁首英雄區 --- */
.hero {
  padding: 8rem 2rem 4rem;
  text-align: center;
  background: var(--bg-secondary);
  position: relative;
  overflow: hidden;
}

.hero::before {
  content: '';
  position: absolute;
  top: -50%;
  left: -50%;
  width: 200%;
  height: 200%;
  background: radial-gradient(circle at 30% 50%, rgba(67,97,238,0.05) 0%, transparent 50%),
              radial-gradient(circle at 70% 50%, rgba(58,12,163,0.05) 0%, transparent 50%);
  animation: heroGlow 10s ease-in-out infinite alternate;
}

@keyframes heroGlow {
  0% { transform: translate(0, 0) rotate(0deg); }
  100% { transform: translate(2%, 2%) rotate(3deg); }
}

.hero-content {
  position: relative;
  z-index: 1;
  max-width: 800px;
  margin: 0 auto;
}

.hero h1 {
  font-size: 3rem;
  font-weight: 800;
  margin-bottom: 1rem;
  background: var(--accent-gradient);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
}

.hero p {
  font-size: 1.2rem;
  color: var(--text-secondary);
  max-width: 600px;
  margin: 0 auto 2rem;
  line-height: 1.8;
}

/* --- 學習路徑卡片 --- */
.path-section {
  padding: 4rem 2rem;
  max-width: 1200px;
  margin: 0 auto;
}

.section-title {
  text-align: center;
  font-size: 2rem;
  font-weight: 700;
  margin-bottom: 3rem;
  color: var(--text-primary);
}

.path-cards {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 2rem;
  margin-bottom: 3rem;
}

.path-card {
  background: var(--card-bg);
  border: 1px solid var(--border-color);
  border-radius: 16px;
  padding: 2rem;
  position: relative;
  overflow: hidden;
  transition: all 0.3s;
  box-shadow: var(--card-shadow);
}
.path-card:hover {
  transform: translateY(-4px);
  box-shadow: 0 8px 24px rgba(0,0,0,0.12);
}

.path-card .level-tag {
  display: inline-block;
  padding: 0.25rem 0.75rem;
  border-radius: 20px;
  font-size: 0.8rem;
  font-weight: 600;
  margin-bottom: 1rem;
  text-transform: uppercase;
}
.level-tag.beginner { background: rgba(46,196,182,0.15); color: var(--tag-beginner); }
.level-tag.intermediate { background: rgba(255,159,28,0.15); color: var(--tag-intermediate); }
.level-tag.advanced { background: rgba(231,29,54,0.15); color: var(--tag-advanced); }

.path-card h3 {
  font-size: 1.3rem;
  margin-bottom: 0.75rem;
}

.path-card p {
  color: var(--text-secondary);
  font-size: 0.9rem;
  margin-bottom: 1.5rem;
}

.path-card .chapter-list {
  list-style: none;
}
.path-card .chapter-list li {
  padding: 0.4rem 0;
  font-size: 0.9rem;
  color: var(--text-secondary);
  border-bottom: 1px solid var(--border-color);
  display: flex;
  align-items: center;
  gap: 0.5rem;
}
.path-card .chapter-list li:last-child {
  border-bottom: none;
}
.path-card .chapter-list .ch-num {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  width: 24px;
  height: 24px;
  border-radius: 6px;
  font-size: 0.75rem;
  font-weight: 700;
  color: white;
  flex-shrink: 0;
}
.ch-num.beginner { background: var(--tag-beginner); }
.ch-num.intermediate { background: var(--tag-intermediate); }
.ch-num.advanced { background: var(--tag-advanced); }
.ch-num.omo { background: var(--accent-primary); }

/* --- 通用內容區塊 --- */
.container {
  max-width: 1200px;
  margin: 0 auto;
  padding: 0 2rem;
}

.content-section {
  padding: 6rem 0 4rem;
}

.page-header {
  padding: 7rem 2rem 2rem;
  background: var(--bg-secondary);
  border-bottom: 1px solid var(--border-color);
}

.page-header h1 {
  font-size: 2.5rem;
  font-weight: 800;
  margin-bottom: 0.5rem;
}

.page-header .breadcrumb {
  font-size: 0.85rem;
  color: var(--text-muted);
  margin-bottom: 1rem;
  display: flex;
  gap: 0.5rem;
  align-items: center;
}
.breadcrumb a { color: var(--text-muted); }
.breadcrumb a:hover { color: var(--accent-primary); }
.breadcrumb .sep { color: var(--text-muted); }

/* --- 學習目標卡 --- */
.learning-goals {
  background: var(--bg-tertiary);
  border-radius: 12px;
  padding: 1.5rem 2rem;
  margin: 1.5rem 0;
  border-left: 4px solid var(--accent-primary);
}
.learning-goals h3 {
  font-size: 1rem;
  font-weight: 700;
  margin-bottom: 0.75rem;
  color: var(--accent-primary);
}
.learning-goals ul {
  list-style: none;
  padding: 0;
}
.learning-goals li {
  padding: 0.3rem 0;
  font-size: 0.95rem;
  color: var(--text-secondary);
}
.learning-goals li::before {
  content: '🎯 ';
}

/* --- 內容區塊 --- */
.content-block {
  margin: 2.5rem 0;
}
.content-block h2 {
  font-size: 1.8rem;
  font-weight: 700;
  margin-bottom: 1rem;
  padding-bottom: 0.5rem;
  border-bottom: 2px solid var(--accent-primary);
}
.content-block h3 {
  font-size: 1.4rem;
  font-weight: 600;
  margin: 1.5rem 0 0.75rem;
}
.content-block h4 {
  font-size: 1.1rem;
  font-weight: 600;
  margin: 1rem 0 0.5rem;
}
.content-block p {
  margin-bottom: 1rem;
  color: var(--text-secondary);
  line-height: 1.8;
}

/* --- 提示框 --- */
.tip-box {
  background: rgba(46,196,182,0.08);
  border: 1px solid rgba(46,196,182,0.3);
  border-radius: 10px;
  padding: 1rem 1.5rem;
  margin: 1.5rem 0;
  border-left: 4px solid var(--success);
}
.tip-box strong { color: var(--success); }

.warning-box {
  background: rgba(255,159,28,0.08);
  border: 1px solid rgba(255,159,28,0.3);
  border-radius: 10px;
  padding: 1rem 1.5rem;
  margin: 1.5rem 0;
  border-left: 4px solid var(--warning);
}
.warning-box strong { color: var(--warning); }

.info-box {
  background: rgba(67,97,238,0.08);
  border: 1px solid rgba(67,97,238,0.3);
  border-radius: 10px;
  padding: 1rem 1.5rem;
  margin: 1.5rem 0;
  border-left: 4px solid var(--accent-primary);
}
.info-box strong { color: var(--accent-primary); }

/* --- 程式碼區塊 --- */
pre {
  background: var(--code-bg);
  color: var(--code-text);
  border-radius: 10px;
  padding: 1.25rem;
  overflow-x: auto;
  margin: 1rem 0;
  position: relative;
  font-family: 'JetBrains Mono', 'Fira Code', 'Cascadia Code', 'Consolas', monospace;
  font-size: 0.9rem;
  line-height: 1.6;
}

pre .copy-btn {
  position: absolute;
  top: 0.5rem;
  right: 0.5rem;
  background: rgba(255,255,255,0.1);
  border: none;
  color: var(--code-text);
  padding: 0.3rem 0.6rem;
  border-radius: 4px;
  font-size: 0.75rem;
  cursor: pointer;
  opacity: 0;
  transition: opacity 0.2s;
}
pre:hover .copy-btn {
  opacity: 1;
}
pre .copy-btn:hover {
  background: rgba(255,255,255,0.2);
}

code {
  font-family: 'JetBrains Mono', 'Fira Code', 'Consolas', monospace;
  font-size: 0.9em;
  background: var(--bg-tertiary);
  padding: 0.15em 0.4em;
  border-radius: 4px;
}
pre code {
  background: none;
  padding: 0;
  border-radius: 0;
}

/* --- 表格 --- */
.table-wrap {
  overflow-x: auto;
  margin: 1.5rem 0;
}
table {
  width: 100%;
  border-collapse: collapse;
  font-size: 0.9rem;
}
thead th {
  background: var(--bg-tertiary);
  padding: 0.75rem 1rem;
  text-align: left;
  font-weight: 600;
  border-bottom: 2px solid var(--border-color);
}
tbody td {
  padding: 0.75rem 1rem;
  border-bottom: 1px solid var(--border-color);
  color: var(--text-secondary);
}
tbody tr:hover {
  background: var(--bg-tertiary);
}

/* --- 頁尾 --- */
.footer {
  background: var(--footer-bg);
  color: var(--footer-text);
  padding: 3rem 2rem;
  text-align: center;
  margin-top: 4rem;
}
.footer a {
  color: var(--accent-primary);
}
.footer .footer-links {
  display: flex;
  justify-content: center;
  gap: 2rem;
  margin-bottom: 1.5rem;
  flex-wrap: wrap;
}
.footer .footer-links a {
  font-size: 0.9rem;
  color: var(--footer-text);
}
.footer .footer-links a:hover {
  color: var(--accent-primary);
}

/* --- 章節導覽（上下頁） --- */
.chapter-nav {
  display: flex;
  justify-content: space-between;
  margin: 3rem 0;
  gap: 1rem;
}
.chapter-nav a {
  flex: 1;
  padding: 1rem 1.5rem;
  border: 1px solid var(--border-color);
  border-radius: 10px;
  text-align: center;
  transition: all 0.3s;
  background: var(--card-bg);
}
.chapter-nav a:hover {
  border-color: var(--accent-primary);
  text-decoration: none;
  transform: translateY(-2px);
  box-shadow: 0 4px 12px rgba(0,0,0,0.1);
}
.chapter-nav .nav-label {
  font-size: 0.75rem;
  color: var(--text-muted);
  text-transform: uppercase;
  letter-spacing: 0.05em;
}
.chapter-nav .nav-title {
  font-weight: 600;
  color: var(--text-primary);
}
.chapter-nav a.disabled {
  opacity: 0.4;
  pointer-events: none;
}

/* --- 互動 CLI 模擬器 --- */
.cli-simulator {
  background: #1a1a2e;
  border-radius: 12px;
  overflow: hidden;
  margin: 1.5rem 0;
  box-shadow: 0 4px 16px rgba(0,0,0,0.3);
}
.cli-simulator .cli-header {
  background: #2a2a3e;
  padding: 0.5rem 1rem;
  display: flex;
  align-items: center;
  gap: 0.5rem;
}
.cli-simulator .cli-dot {
  width: 12px;
  height: 12px;
  border-radius: 50%;
}
.cli-dot.red { background: #ff5f56; }
.cli-dot.yellow { background: #ffbd2e; }
.cli-dot.green { background: #27c93f; }
.cli-simulator .cli-title {
  color: #888;
  font-size: 0.8rem;
  margin-left: 0.5rem;
}
.cli-simulator .cli-body {
  padding: 1.25rem;
  font-family: 'JetBrains Mono', 'Fira Code', monospace;
  font-size: 0.85rem;
  line-height: 1.7;
  color: #cdd6f4;
}
.cli-simulator .cli-prompt {
  color: #89b4fa;
}
.cli-simulator .cli-output {
  color: #a6adc8;
}
.cli-simulator .cli-success {
  color: #a6e3a1;
}
.cli-simulator .cli-error {
  color: #f38ba8;
}
.cli-simulator .cli-cursor {
  display: inline-block;
  width: 8px;
  height: 1.1em;
  background: #89b4fa;
  animation: blink 1s step-end infinite;
  vertical-align: text-bottom;
  margin-left: 2px;
}
@keyframes blink {
  50% { opacity: 0; }
}

/* --- 小測驗 --- */
.quiz-card {
  background: var(--card-bg);
  border: 1px solid var(--border-color);
  border-radius: 12px;
  padding: 1.5rem;
  margin: 1.5rem 0;
}
.quiz-question {
  font-weight: 600;
  margin-bottom: 1rem;
  font-size: 1.05rem;
}
.quiz-options label {
  display: block;
  padding: 0.75rem 1rem;
  border: 1px solid var(--border-color);
  border-radius: 8px;
  margin-bottom: 0.5rem;
  cursor: pointer;
  transition: all 0.2s;
  font-size: 0.95rem;
}
.quiz-options label:hover {
  background: var(--bg-tertiary);
}
.quiz-options input[type="radio"] {
  margin-right: 0.75rem;
}
.quiz-options input[type="radio"]:checked + span {
  color: var(--accent-primary);
  font-weight: 600;
}
.quiz-btn {
  background: var(--accent-gradient);
  color: white;
  border: none;
  padding: 0.6rem 1.5rem;
  border-radius: 8px;
  font-size: 0.9rem;
  font-weight: 600;
  cursor: pointer;
  margin-top: 1rem;
  transition: all 0.2s;
}
.quiz-btn:hover {
  transform: translateY(-1px);
  box-shadow: 0 4px 12px rgba(67,97,238,0.3);
}
.quiz-result {
  margin-top: 1rem;
  padding: 1rem;
  border-radius: 8px;
  font-weight: 600;
  display: none;
}
.quiz-result.correct {
  background: rgba(46,196,182,0.1);
  color: var(--success);
  border: 1px solid rgba(46,196,182,0.3);
  display: block;
}
.quiz-result.incorrect {
  background: rgba(231,29,54,0.1);
  color: var(--danger);
  border: 1px solid rgba(231,29,54,0.3);
  display: block;
}

/* --- 進度追蹤 --- */
.progress-bar-container {
  background: var(--bg-tertiary);
  border-radius: 12px;
  padding: 1.5rem;
  margin: 1.5rem 0;
}
.progress-bar {
  height: 8px;
  background: var(--border-color);
  border-radius: 4px;
  overflow: hidden;
  margin-top: 0.5rem;
}
.progress-bar .progress-fill {
  height: 100%;
  background: var(--accent-gradient);
  border-radius: 4px;
  transition: width 0.5s ease;
}
.progress-text {
  display: flex;
  justify-content: space-between;
  font-size: 0.85rem;
  color: var(--text-muted);
}

/* --- 圖文卡片 --- */
.feature-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
  gap: 1.5rem;
  margin: 2rem 0;
}
.feature-card, .path-card {
  background: var(--card-bg);
  border: 1px solid var(--border-color);
  border-radius: 12px;
  padding: 1.5rem;
  transition: all 0.3s cubic-bezier(0.4, 0, 0.2, 1);
  position: relative;
}
.feature-card::after, .path-card::after {
  content: '';
  position: absolute;
  inset: 0;
  border-radius: 12px;
  background: var(--accent-gradient);
  opacity: 0;
  transition: opacity 0.3s ease;
  z-index: -1;
  filter: blur(20px);
}
.feature-card:hover, .path-card:hover {
  transform: translateY(-4px);
  box-shadow: 0 8px 30px rgba(67,97,238,0.15);
  border-color: var(--accent-primary);
}
.feature-card .icon {
  font-size: 2rem;
  margin-bottom: 0.75rem;
}
.feature-card h4 {
  font-size: 1.1rem;
  font-weight: 600;
  margin-bottom: 0.5rem;
}
.feature-card p {
  font-size: 0.9rem;
  color: var(--text-secondary);
  line-height: 1.6;
}

/* --- FAQ --- */
.faq-item {
  border: 1px solid var(--border-color);
  border-radius: 10px;
  margin-bottom: 0.75rem;
  overflow: hidden;
}
.faq-question {
  padding: 1rem 1.25rem;
  background: var(--card-bg);
  cursor: pointer;
  font-weight: 600;
  display: flex;
  justify-content: space-between;
  align-items: center;
  transition: background 0.2s;
  user-select: none;
}
.faq-question:hover {
  background: var(--bg-tertiary);
}
.faq-question .arrow {
  transition: transform 0.3s;
  font-size: 0.8rem;
}
.faq-question.active .arrow {
  transform: rotate(180deg);
}
.faq-answer {
  padding: 0 1.25rem;
  max-height: 0;
  overflow: hidden;
  transition: all 0.3s ease;
  color: var(--text-secondary);
}
.faq-answer.open {
  padding: 0 1.25rem 1rem;
  max-height: 500px;
}

/* --- 回應式設計 --- */
@media (max-width: 1024px) {
  .path-cards {
    grid-template-columns: repeat(2, 1fr);
  }
}

@media (max-width: 768px) {
  .navbar { padding: 0 1rem; }
  .navbar-links { display: none; }
  .navbar-links.open {
    display: flex;
    flex-direction: column;
    position: absolute;
    top: 64px;
    left: 0;
    right: 0;
    background: var(--nav-bg);
    border-bottom: 1px solid var(--border-color);
    padding: 1rem;
    backdrop-filter: blur(12px);
  }
  .mobile-menu-btn { display: block; }

  .hero { padding: 6rem 1rem 3rem; }
  .hero h1 { font-size: 2rem; }

  .path-cards {
    grid-template-columns: 1fr;
  }

  .page-header h1 { font-size: 1.8rem; }

  .content-section { padding: 5rem 0 2rem; }
  .container { padding: 0 1rem; }

  .chapter-nav { flex-direction: column; }
}

@media (max-width: 480px) {
  .hero h1 { font-size: 1.6rem; }
  .feature-grid { grid-template-columns: 1fr; }
}