/* 
 * Vibe Coding 課程介紹網站 - 核心樣式表
 * 專為初學者設計：使用 CSS 變數與現代 CSS 特性，結構清晰且好懂。
 * 稍微複雜的動畫與毛玻璃濾鏡皆附有詳細的繁體中文註解。
 */

/* ==========================================
   1. 外部字型與基本重設
   ========================================== */
@import url('https://fonts.googleapis.com/css2?family=Outfit:wght@300;400;600;800&family=Space+Grotesk:wght@400;700&display=swap');

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

html {
  scroll-behavior: smooth;
}

/* ==========================================
   2. 全域變數系統 (CSS Variables)
   * 透過切換 body 的 class 來改變這組變數，即可輕鬆變更全站主題！
   ========================================== */
:root {
  /* Lofi Chill 預設主題 (極光綠藍色調) */
  --bg-color: #0a0b10;
  --panel-bg: rgba(18, 22, 40, 0.65);
  --panel-border: rgba(255, 255, 255, 0.06);
  --text-primary: #f8fafc;
  --text-secondary: #94a3b8;
  
  --neon-1: #00f2fe;
  --neon-2: #4facfe;
  --neon-glow: rgba(0, 242, 254, 0.25);
  
  --font-title: 'Space Grotesk', 'Outfit', -apple-system, sans-serif;
  --font-body: 'Outfit', -apple-system, sans-serif;
  --transition-smooth: all 0.5s cubic-bezier(0.16, 1, 0.3, 1);
  --pulse-speed: 2.5s;
  --visualizer-speed: 1.2s;
}

/* Synthwave Neon 主題 (粉紫霓虹色調) */
body.vibe-synthwave {
  --bg-color: #0b020f;
  --panel-bg: rgba(27, 10, 36, 0.7);
  --panel-border: rgba(255, 0, 127, 0.15);
  --text-primary: #fff2f8;
  --text-secondary: #c084fc;
  
  --neon-1: #ff007f;
  --neon-2: #7928ca;
  --neon-glow: rgba(255, 0, 127, 0.3);
  --pulse-speed: 1.8s;
  --visualizer-speed: 0.8s;
}

/* Cyberpunk Techno 主題 (極客黃綠色調) */
body.vibe-cyberpunk {
  --bg-color: #040908;
  --panel-bg: rgba(10, 26, 24, 0.75);
  --panel-border: rgba(0, 255, 204, 0.18);
  --text-primary: #e0fcf6;
  --text-secondary: #2dd4bf;
  
  --neon-1: #f3f915;
  --neon-2: #00ffcc;
  --neon-glow: rgba(0, 255, 204, 0.35);
  --pulse-speed: 1.2s;
  --visualizer-speed: 0.5s;
}

/* ==========================================
   3. 基礎與版面樣式
   ========================================== */
body {
  font-family: var(--font-body);
  background-color: var(--bg-color);
  color: var(--text-primary);
  line-height: 1.6;
  overflow-x: hidden;
  transition: var(--transition-smooth);
}

/* 背景發光氣泡效果 - 營造氛圍感 */
.bg-glow-container {
  position: fixed;
  top: 0;
  left: 0;
  width: 100vw;
  height: 100vh;
  z-index: -1;
  overflow: hidden;
  pointer-events: none;
}

.bg-glow-1, .bg-glow-2 {
  position: absolute;
  width: 500px;
  height: 500px;
  border-radius: 50%;
  filter: blur(140px);
  opacity: 0.18;
  transition: var(--transition-smooth);
}

/* 第一個發光球：左上角 */
.bg-glow-1 {
  top: -10%;
  left: -5%;
  background: radial-gradient(circle, var(--neon-1) 0%, transparent 70%);
  animation: floatGlow 15s infinite alternate ease-in-out;
}

/* 第二個發光球：右下角 */
.bg-glow-2 {
  bottom: -10%;
  right: -5%;
  background: radial-gradient(circle, var(--neon-2) 0%, transparent 70%);
  animation: floatGlow 20s infinite alternate-reverse ease-in-out;
}

/* 浮動動畫 */
@keyframes floatGlow {
  0% { transform: translate(0, 0) scale(1); }
  100% { transform: translate(80px, 50px) scale(1.15); }
}

/* ==========================================
   4. 導覽列與首頁頂部 (Header & Nav)
   ========================================== */
header {
  position: sticky;
  top: 0;
  width: 100%;
  z-index: 100;
  background: rgba(var(--bg-color), 0.7);
  backdrop-filter: blur(12px); /* 毛玻璃模糊濾鏡 */
  -webkit-backdrop-filter: blur(12px);
  border-bottom: 1px solid var(--panel-border);
  transition: var(--transition-smooth);
}

.nav-container {
  max-width: 1200px;
  margin: 0 auto;
  padding: 1.2rem 2rem;
  display: flex;
  justify-content: space-between;
  align-items: center;
}

.logo {
  font-family: var(--font-title);
  font-size: 1.5rem;
  font-weight: 700;
  letter-spacing: -0.5px;
  text-decoration: none;
  color: var(--text-primary);
  display: flex;
  align-items: center;
  gap: 0.5rem;
}

.logo span {
  background: linear-gradient(135deg, var(--neon-1), var(--neon-2));
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
}

.logo-badge {
  font-size: 0.75rem;
  padding: 0.2rem 0.6rem;
  border-radius: 50px;
  background: var(--panel-bg);
  border: 1px solid var(--panel-border);
  color: var(--text-secondary);
  font-weight: 400;
}

.nav-links {
  display: flex;
  gap: 2.2rem;
  list-style: none;
}

.nav-links a {
  text-decoration: none;
  color: var(--text-secondary);
  font-weight: 400;
  transition: var(--transition-smooth);
  font-size: 0.95rem;
}

.nav-links a:hover {
  color: var(--text-primary);
  text-shadow: 0 0 10px var(--neon-glow);
}

.cta-btn {
  text-decoration: none;
  background: linear-gradient(135deg, var(--neon-1) 0%, var(--neon-2) 100%);
  color: #000;
  font-weight: 600;
  padding: 0.6rem 1.4rem;
  border-radius: 50px;
  box-shadow: 0 4px 15px var(--neon-glow);
  transition: var(--transition-smooth);
  font-size: 0.9rem;
}

.cta-btn:hover {
  transform: translateY(-2px);
  box-shadow: 0 8px 25px var(--neon-glow);
}

/* ==========================================
   5. Hero 主視覺區
   ========================================== */
.hero {
  padding: 8rem 2rem 5rem 2rem;
  max-width: 1000px;
  margin: 0 auto;
  text-align: center;
  position: relative;
}

.hero-badge {
  display: inline-flex;
  align-items: center;
  gap: 0.5rem;
  background: rgba(255, 255, 255, 0.03);
  border: 1px solid var(--panel-border);
  padding: 0.4rem 1rem;
  border-radius: 50px;
  font-size: 0.85rem;
  color: var(--neon-2);
  margin-bottom: 2rem;
  box-shadow: inset 0 1px 1px rgba(255, 255, 255, 0.05);
}

.hero-badge i {
  animation: pulseGlow var(--pulse-speed) infinite;
}

@keyframes pulseGlow {
  0%, 100% { opacity: 0.4; }
  50% { opacity: 1; }
}

.hero h1 {
  font-family: var(--font-title);
  font-size: 4rem;
  font-weight: 800;
  line-height: 1.15;
  letter-spacing: -2px;
  margin-bottom: 1.5rem;
}

.gradient-text {
  background: linear-gradient(135deg, var(--neon-1) 0%, var(--neon-2) 100%);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  display: inline-block;
  position: relative;
}

.hero p {
  font-size: 1.25rem;
  color: var(--text-secondary);
  max-width: 680px;
  margin: 0 auto 3rem auto;
  line-height: 1.8;
}

.hero-actions {
  display: flex;
  justify-content: center;
  gap: 1.2rem;
}

.btn-primary {
  cursor: pointer;
  border: none;
  font-family: var(--font-body);
  font-size: 1rem;
  font-weight: 600;
  padding: 1rem 2.2rem;
  border-radius: 50px;
  background: linear-gradient(135deg, var(--neon-1) 0%, var(--neon-2) 100%);
  color: #05070f;
  box-shadow: 0 4px 20px var(--neon-glow);
  transition: var(--transition-smooth);
}

.btn-primary:hover {
  transform: translateY(-3px) scale(1.02);
  box-shadow: 0 10px 30px var(--neon-glow);
}

.btn-secondary {
  cursor: pointer;
  font-family: var(--font-body);
  font-size: 1rem;
  font-weight: 600;
  padding: 1rem 2.2rem;
  border-radius: 50px;
  background: var(--panel-bg);
  border: 1px solid var(--panel-border);
  color: var(--text-primary);
  backdrop-filter: blur(5px);
  transition: var(--transition-smooth);
}

.btn-secondary:hover {
  border-color: var(--neon-1);
  background: rgba(255, 255, 255, 0.03);
  transform: translateY(-2px);
}

/* ==========================================
   6. Vibe 控制台 (互動區)
   ========================================== */
.section-title {
  font-family: var(--font-title);
  font-size: 2.2rem;
  text-align: center;
  margin-bottom: 0.8rem;
  letter-spacing: -0.5px;
}

.section-subtitle {
  color: var(--text-secondary);
  text-align: center;
  margin-bottom: 3.5rem;
  font-size: 1.05rem;
}

.vibe-console-section {
  padding: 5rem 2rem;
  max-width: 1000px;
  margin: 0 auto;
}

/* 控制台毛玻璃卡片 */
.vibe-console-card {
  background: var(--panel-bg);
  border: 1px solid var(--panel-border);
  border-radius: 24px;
  padding: 3rem;
  backdrop-filter: blur(20px);
  -webkit-backdrop-filter: blur(20px);
  box-shadow: 0 20px 50px rgba(0, 0, 0, 0.3), inset 0 1px 0 rgba(255, 255, 255, 0.05);
  display: grid;
  grid-template-columns: 1.2fr 0.8fr;
  gap: 3rem;
  align-items: center;
  transition: var(--transition-smooth);
  position: relative;
  overflow: hidden;
}

.vibe-console-card::before {
  content: '';
  position: absolute;
  top: 0;
  left: 0;
  width: 100%;
  height: 4px;
  background: linear-gradient(90deg, var(--neon-1), var(--neon-2));
}

.vibe-controls-info h3 {
  font-family: var(--font-title);
  font-size: 1.6rem;
  margin-bottom: 1rem;
}

.vibe-controls-info p {
  color: var(--text-secondary);
  margin-bottom: 2rem;
  font-size: 1rem;
}

/* 控制按鈕組 */
.vibe-selector-group {
  display: flex;
  flex-direction: column;
  gap: 1rem;
}

.vibe-select-btn {
  cursor: pointer;
  background: rgba(255, 255, 255, 0.02);
  border: 1px solid var(--panel-border);
  border-radius: 14px;
  padding: 1.2rem;
  display: flex;
  align-items: center;
  justify-content: space-between;
  color: var(--text-secondary);
  transition: var(--transition-smooth);
  font-family: var(--font-body);
}

.vibe-btn-left {
  display: flex;
  align-items: center;
  gap: 1rem;
}

.vibe-btn-icon {
  font-size: 1.5rem;
}

.vibe-btn-text h4 {
  color: var(--text-primary);
  font-size: 1.05rem;
  font-weight: 600;
  text-align: left;
  margin-bottom: 0.15rem;
}

.vibe-btn-text p {
  font-size: 0.8rem;
  color: var(--text-secondary);
  margin: 0;
}

.vibe-select-btn i.fa-chevron-right {
  opacity: 0;
  transform: translateX(-5px);
  transition: var(--transition-smooth);
}

/* 按鈕選中狀態 */
.vibe-select-btn.active {
  background: rgba(255, 255, 255, 0.05);
  border-color: var(--neon-1);
  box-shadow: 0 0 15px rgba(var(--neon-1), 0.1);
}

.vibe-select-btn.active i.fa-chevron-right {
  opacity: 1;
  transform: translateX(0);
  color: var(--neon-1);
}

.vibe-select-btn:hover:not(.active) {
  border-color: rgba(255, 255, 255, 0.15);
  background: rgba(255, 255, 255, 0.04);
}

/* 音量與音樂播放器顯示區 */
.player-visualizer-container {
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 2rem;
  background: rgba(0, 0, 0, 0.2);
  border-radius: 18px;
  padding: 2rem;
  border: 1px solid rgba(255, 255, 255, 0.02);
}

/* 模擬黑膠唱片/光碟旋轉效果 */
.disc-wrapper {
  position: relative;
  width: 140px;
  height: 140px;
}

.disc-element {
  width: 100%;
  height: 100%;
  border-radius: 50%;
  background: radial-gradient(circle, #222 25%, #050505 26%, #111 60%, #000 61%, var(--neon-2) 100%);
  border: 4px solid var(--panel-border);
  box-shadow: 0 10px 25px rgba(0, 0, 0, 0.5), 0 0 30px var(--neon-glow);
  display: flex;
  align-items: center;
  justify-content: center;
  animation: rotateDisc 10s infinite linear;
  transition: var(--transition-smooth);
}

.disc-center {
  width: 32px;
  height: 32px;
  border-radius: 50%;
  background: var(--bg-color);
  border: 2px solid var(--neon-1);
  display: flex;
  align-items: center;
  justify-content: center;
}

.disc-center::after {
  content: '';
  width: 8px;
  height: 8px;
  border-radius: 50%;
  background: var(--text-primary);
}

@keyframes rotateDisc {
  from { transform: rotate(0deg); }
  to { transform: rotate(360deg); }
}

/* 當前播放曲目跑馬燈 */
.current-track-card {
  width: 100%;
  text-align: center;
  overflow: hidden;
  white-space: nowrap;
  position: relative;
  padding: 0.5rem 0;
}

.current-track-title {
  display: inline-block;
  font-size: 0.9rem;
  color: var(--neon-2);
  font-weight: 600;
  animation: marquee 12s infinite linear;
}

@keyframes marquee {
  0% { transform: translateX(100%); }
  100% { transform: translateX(-100%); }
}

/* 音波圖視覺化 (模擬動態音頻波形) */
.audio-visualizer {
  display: flex;
  align-items: flex-end;
  gap: 4px;
  height: 45px;
  width: 160px;
}

.visualizer-bar {
  flex: 1;
  background: linear-gradient(to top, var(--neon-2), var(--neon-1));
  border-radius: 3px 3px 0 0;
  height: 10%;
  animation: bounceBar var(--visualizer-speed) infinite ease-in-out alternate;
  box-shadow: 0 0 10px var(--neon-glow);
}

/* 為每根音波設定不同的延遲，製造起伏參差不齊的效果 */
.visualizer-bar:nth-child(2) { animation-delay: 0.15s; }
.visualizer-bar:nth-child(3) { animation-delay: 0.3s; }
.visualizer-bar:nth-child(4) { animation-delay: 0.05s; }
.visualizer-bar:nth-child(5) { animation-delay: 0.4s; }
.visualizer-bar:nth-child(6) { animation-delay: 0.2s; }
.visualizer-bar:nth-child(7) { animation-delay: 0.35s; }
.visualizer-bar:nth-child(8) { animation-delay: 0.1s; }

@keyframes bounceBar {
  0% { height: 10%; }
  100% { height: 100%; }
}

/* ==========================================
   7. 課程大綱區 (Curriculum Cards)
   ========================================== */
.curriculum-section {
  padding: 5rem 2rem;
  max-width: 1200px;
  margin: 0 auto;
}

.grid-cards {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(320px, 1fr));
  gap: 2rem;
}

.curriculum-card {
  background: var(--panel-bg);
  border: 1px solid var(--panel-border);
  border-radius: 20px;
  padding: 2.5rem;
  backdrop-filter: blur(15px);
  -webkit-backdrop-filter: blur(15px);
  transition: var(--transition-smooth);
  position: relative;
  display: flex;
  flex-direction: column;
  justify-content: space-between;
}

.curriculum-card:hover {
  transform: translateY(-8px);
  border-color: var(--neon-1);
  box-shadow: 0 15px 35px var(--neon-glow);
}

.card-num {
  font-family: var(--font-title);
  font-size: 3rem;
  font-weight: 700;
  line-height: 1;
  background: linear-gradient(135deg, var(--neon-1) 0%, transparent 100%);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  margin-bottom: 1rem;
}

.curriculum-card h3 {
  font-family: var(--font-title);
  font-size: 1.35rem;
  margin-bottom: 1rem;
  font-weight: 700;
}

.curriculum-card p {
  color: var(--text-secondary);
  font-size: 0.95rem;
  line-height: 1.7;
  margin-bottom: 1.5rem;
  flex-grow: 1;
}

.card-features {
  list-style: none;
}

.card-features li {
  display: flex;
  align-items: center;
  gap: 0.6rem;
  font-size: 0.85rem;
  color: var(--text-primary);
  margin-bottom: 0.5rem;
}

.card-features i {
  color: var(--neon-1);
}

/* ==========================================
   7.2 導師介紹區 (Instructor Section)
   ========================================== */
.instructor-section {
  padding: 5rem 2rem;
  max-width: 900px;
  margin: 0 auto;
}

.instructor-card {
  background: var(--panel-bg);
  border: 1px solid var(--panel-border);
  border-radius: 24px;
  padding: 3rem;
  backdrop-filter: blur(20px);
  -webkit-backdrop-filter: blur(20px);
  display: flex;
  gap: 3rem;
  align-items: center;
  transition: var(--transition-smooth);
  box-shadow: 0 20px 40px rgba(0, 0, 0, 0.25);
  position: relative;
}

.instructor-card:hover {
  border-color: var(--neon-2);
  box-shadow: 0 15px 30px var(--neon-glow);
}

/* 科技感虛擬頭像 */
.instructor-avatar-container {
  flex-shrink: 0;
}

.instructor-avatar {
  width: 140px;
  height: 140px;
  border-radius: 50%;
  background: linear-gradient(135deg, var(--neon-2) 0%, var(--neon-1) 100%);
  display: flex;
  align-items: center;
  justify-content: center;
  box-shadow: 0 0 25px var(--neon-glow);
  position: relative;
  border: 4px solid var(--bg-color);
  animation: avatarFloat 6s infinite ease-in-out alternate;
}

.instructor-avatar span {
  font-family: var(--font-title);
  font-size: 4.5rem;
  font-weight: 800;
  color: #05070f;
  text-shadow: 0 2px 4px rgba(0,0,0,0.15);
}

.instructor-avatar img {
  width: 100%;
  height: 100%;
  object-fit: cover;
  object-position: top;
  border-radius: 50%;
  display: block;
}

@keyframes avatarFloat {
  0% { transform: translateY(0) rotate(0deg); }
  100% { transform: translateY(-8px) rotate(3deg); }
}

.instructor-info {
  flex-grow: 1;
}

.instructor-header {
  display: flex;
  align-items: center;
  gap: 1.2rem;
  margin-bottom: 1rem;
  flex-wrap: wrap;
}

.instructor-name {
  font-family: var(--font-title);
  font-size: 1.8rem;
  font-weight: 700;
  color: var(--text-primary);
}

.instructor-tag {
  background: rgba(255, 255, 255, 0.05);
  border: 1px solid var(--panel-border);
  color: var(--neon-1);
  padding: 0.2rem 0.8rem;
  border-radius: 50px;
  font-size: 0.8rem;
  font-weight: 600;
  display: inline-flex;
  align-items: center;
  gap: 0.4rem;
}

.instructor-bio {
  color: var(--text-secondary);
  font-size: 0.95rem;
  line-height: 1.8;
  margin-bottom: 2rem;
}

.instructor-stats {
  display: flex;
  gap: 2.5rem;
  border-top: 1px solid var(--panel-border);
  padding-top: 1.5rem;
}

.stat-item {
  display: flex;
  flex-direction: column;
}

.stat-num {
  font-family: var(--font-title);
  font-size: 1.6rem;
  font-weight: 700;
  color: var(--neon-2);
}

.stat-label {
  font-size: 0.8rem;
  color: var(--text-secondary);
  margin-top: 0.2rem;
}

/* 配合行動裝置的排版調整 */
@media (max-width: 768px) {
  .instructor-card {
    flex-direction: column;
    text-align: center;
    padding: 2.5rem 1.8rem;
    gap: 2rem;
  }
  
  .instructor-header {
    justify-content: center;
  }
  
  .instructor-stats {
    justify-content: center;
    gap: 1.5rem;
  }
}

/* ==========================================
   8. 精神看板 (Vibe Philosophy)
   ========================================== */
.philosophy-section {
  padding: 6rem 2rem;
  max-width: 1000px;
  margin: 0 auto;
  text-align: center;
}

.philosophy-banner {
  background: radial-gradient(circle at top left, rgba(255,255,255,0.02), transparent), var(--panel-bg);
  border: 1px solid var(--panel-border);
  border-radius: 24px;
  padding: 4rem 2rem;
  position: relative;
  overflow: hidden;
}

.philosophy-banner::after {
  content: '';
  position: absolute;
  width: 150px;
  height: 150px;
  background: var(--neon-glow);
  filter: blur(50px);
  border-radius: 50%;
  top: -75px;
  right: -75px;
  pointer-events: none;
}

.philosophy-banner blockquote {
  font-family: var(--font-title);
  font-size: 1.8rem;
  font-weight: 400;
  line-height: 1.5;
  margin-bottom: 1.5rem;
  color: var(--text-primary);
}

.philosophy-banner blockquote span {
  color: var(--neon-1);
  font-weight: 700;
}

.philosophy-banner cite {
  font-style: normal;
  color: var(--text-secondary);
  font-size: 0.95rem;
}

/* ==========================================
   9. 報名表單區 (Join Us Form)
   ========================================== */
.join-section {
  padding: 5rem 2rem 8rem 2rem;
  max-width: 600px;
  margin: 0 auto;
}

.join-card {
  background: var(--panel-bg);
  border: 1px solid var(--panel-border);
  border-radius: 24px;
  padding: 3rem;
  backdrop-filter: blur(20px);
  -webkit-backdrop-filter: blur(20px);
  box-shadow: 0 20px 40px rgba(0,0,0,0.3);
  position: relative;
}

.form-group {
  margin-bottom: 1.5rem;
}

.form-label {
  display: block;
  font-size: 0.9rem;
  font-weight: 600;
  color: var(--text-primary);
  margin-bottom: 0.5rem;
}

.form-control {
  width: 100%;
  background: rgba(0, 0, 0, 0.25);
  border: 1px solid var(--panel-border);
  border-radius: 10px;
  padding: 0.9rem 1.1rem;
  color: var(--text-primary);
  font-family: var(--font-body);
  font-size: 0.95rem;
  transition: var(--transition-smooth);
}

.form-control:focus {
  outline: none;
  border-color: var(--neon-1);
  box-shadow: 0 0 15px var(--neon-glow);
  background: rgba(0, 0, 0, 0.4);
}

select.form-control {
  appearance: none;
  -webkit-appearance: none;
  background-image: url("data:image/svg+xml;utf8,<svg fill='white' height='24' viewBox='0 0 24 24' width='24' xmlns='http://www.w3.org/2000/svg'><path d='M7 10l5 5 5-5z'/><path d='M0 0h24v24H0z' fill='none'/></svg>");
  background-repeat: no-repeat;
  background-position: right 10px center;
  cursor: pointer;
}

/* 報名成功狀態彈窗與覆蓋層 */
.success-overlay {
  position: fixed;
  top: 0;
  left: 0;
  width: 100vw;
  height: 100vh;
  background: rgba(10, 11, 16, 0.9);
  backdrop-filter: blur(8px);
  z-index: 1000;
  display: flex;
  align-items: center;
  justify-content: center;
  opacity: 0;
  pointer-events: none;
  transition: var(--transition-smooth);
}

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

.success-modal {
  background: var(--panel-bg);
  border: 2px solid var(--neon-1);
  box-shadow: 0 0 35px var(--neon-glow);
  border-radius: 24px;
  padding: 3rem;
  max-width: 450px;
  width: 90%;
  text-align: center;
  transform: scale(0.9);
  transition: var(--transition-smooth);
}

.success-overlay.show .success-modal {
  transform: scale(1);
}

.success-icon {
  width: 70px;
  height: 70px;
  border-radius: 50%;
  background: linear-gradient(135deg, var(--neon-1), var(--neon-2));
  display: flex;
  align-items: center;
  justify-content: center;
  margin: 0 auto 1.5rem auto;
  font-size: 2rem;
  color: #000;
  box-shadow: 0 0 20px var(--neon-glow);
}

.success-modal h3 {
  font-family: var(--font-title);
  font-size: 1.8rem;
  margin-bottom: 0.8rem;
}

.success-modal p {
  color: var(--text-secondary);
  margin-bottom: 2rem;
  font-size: 0.95rem;
}

/* ==========================================
   10. 頁尾與響應式斷點
   ========================================== */
footer {
  border-top: 1px solid var(--panel-border);
  padding: 3rem 2rem;
  text-align: center;
  background: rgba(5, 6, 10, 0.8);
  font-size: 0.9rem;
  color: var(--text-secondary);
}

.footer-socials {
  display: flex;
  justify-content: center;
  gap: 1.5rem;
  margin-bottom: 1.5rem;
}

.footer-socials a {
  color: var(--text-secondary);
  font-size: 1.2rem;
  transition: var(--transition-smooth);
}

.footer-socials a:hover {
  color: var(--neon-1);
  text-shadow: 0 0 8px var(--neon-glow);
}

/* 響應式斷點設定 */
@media (max-width: 900px) {
  .vibe-console-card {
    grid-template-columns: 1fr;
    gap: 2.5rem;
    padding: 2rem;
  }
  
  .hero h1 {
    font-size: 3rem;
  }
}

@media (max-width: 600px) {
  .nav-links, .nav-container .cta-btn {
    display: none; /* 在極小螢幕隱藏一般導覽以保持乾淨 */
  }
  
  .hero {
    padding: 6rem 1rem 3rem 1rem;
  }
  
  .hero h1 {
    font-size: 2.4rem;
  }
  
  .hero-actions {
    flex-direction: column;
    align-items: stretch;
  }
  
  .join-card, .success-modal {
    padding: 2rem 1.5rem;
  }
}