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

    :root {
      --bg-deep: #0c0e14;
      --bg-card: #141720;
      --bg-card-hover: #1a1d28;
      --accent-primary: #6b9eff;
      --accent-glow: rgba(107, 158, 255, 0.2);
      --accent-glow-strong: rgba(107, 158, 255, 0.4);
      --text-primary: #e8eaed;
      --text-secondary: #8b8f9a;
      --text-muted: #4a4d58;
      --border: #2a2d38;
      --border-active: #6b9eff;
      --transition: 300ms cubic-bezier(0.4, 0, 0.2, 1);
    }

    ::selection { background: var(--accent-primary); color: var(--bg-deep); }
    ::-webkit-scrollbar { width: 8px; height: 8px; }
    ::-webkit-scrollbar-track { background: var(--bg-deep); }
    ::-webkit-scrollbar-thumb { background: var(--border); border-radius: 4px; }
    ::-webkit-scrollbar-thumb:hover { background: var(--text-muted); }
    html { scroll-behavior: smooth; }

    body {
      font-family: 'Inter', -apple-system, BlinkMacSystemFont, sans-serif;
      background: var(--bg-deep);
      color: var(--text-primary);
      min-height: 100vh;
      overflow-x: hidden;
      line-height: 1.6;
    }

    body::before {
      content: '';
      position: fixed;
      inset: 0;
      background: radial-gradient(ellipse at 30% 20%, rgba(107, 158, 255, 0.08) 0%, transparent 50%),
                  radial-gradient(ellipse at 70% 80%, rgba(139, 92, 246, 0.06) 0%, transparent 50%);
      pointer-events: none;
      z-index: 1000;
    }

    .container { max-width: 1200px; margin: 0 auto; padding: 0 24px; }

    .ambient-orb {
      position: fixed;
      border-radius: 50%;
      opacity: 0.15;
      pointer-events: none;
      will-change: transform;
    }
    .orb-1 { width: 400px; height: 400px; background: radial-gradient(circle, var(--accent-primary) 0%, transparent 70%); top: -100px; right: -100px; }
    .orb-2 { width: 300px; height: 300px; background: radial-gradient(circle, #8b5cf6 0%, transparent 70%); bottom: -50px; left: -50px; }
    @keyframes float {
      0%, 100% { transform: translate(0, 0); }
      50% { transform: translate(-20px, 20px); }
    }

    header {
      position: fixed;
      top: 0; left: 0; right: 0;
      z-index: 100;
      padding: 20px 0;
      background: linear-gradient(to bottom, var(--bg-deep) 0%, transparent 100%);
    }
    .header-content { display: flex; align-items: center; justify-content: space-between; }
    .logo { display: flex; align-items: center; gap: 12px; }
    .logo-icon {
      width: 36px; height: 36px;
      background: linear-gradient(135deg, var(--accent-primary), #8bb8ff);
      border-radius: 50%;
      display: flex; align-items: center; justify-content: center;
      box-shadow: 0 0 20px var(--accent-glow);
    }
    .logo-icon svg { width: 20px; height: 20px; color: var(--bg-deep); }
    .logo-text { font-family: 'Noto Serif SC', Georgia, serif; font-size: 20px; font-weight: 600; }
    .timer-btn {
      background: transparent;
      border: 1px solid var(--border);
      border-radius: 8px;
      padding: 8px 12px;
      color: var(--text-secondary);
      cursor: pointer;
      display: flex; align-items: center; gap: 6px;
      font-size: 13px;
      transition: var(--transition);
    }
    .timer-btn:hover { border-color: var(--accent-primary); color: var(--accent-primary); }
    .timer-btn.active { background: var(--accent-glow); border-color: var(--accent-primary); color: var(--accent-primary); }
    .timer-btn svg { width: 16px; height: 16px; }

    /* Header actions */
    .header-actions {
      display: flex;
      align-items: center;
      gap: 12px;
    }

    /* Language button */
    .lang-btn {
      background: transparent;
      border: 1px solid var(--border);
      border-radius: 8px;
      padding: 8px 12px;
      color: var(--text-secondary);
      cursor: pointer;
      display: flex; align-items: center; gap: 6px;
      font-size: 13px;
      transition: var(--transition);
    }
    .lang-btn:hover { border-color: var(--accent-primary); color: var(--accent-primary); }
    .lang-btn svg { width: 16px; height: 16px; }
    .lang-current { font-weight: 500; }

    /* Language modal */
    .lang-modal { max-width: 360px; }
    .lang-grid {
      display: grid;
      grid-template-columns: repeat(2, 1fr);
      gap: 8px;
      padding: 8px 0;
    }
    .lang-option {
      display: flex;
      align-items: center;
      gap: 12px;
      padding: 12px 16px;
      background: var(--bg-card);
      border: 1px solid transparent;
      border-radius: 10px;
      cursor: pointer;
      transition: var(--transition);
      text-decoration: none;
      color: var(--text-primary);
    }
    .lang-option:hover {
      background: var(--bg-card-hover);
      border-color: var(--accent-primary);
    }
    .lang-option.current {
      background: var(--accent-glow);
      border-color: var(--accent-primary);
    }
    .lang-option-code {
      font-size: 12px;
      font-weight: 600;
      color: var(--text-muted);
      text-transform: uppercase;
      min-width: 24px;
    }
    .lang-option.current .lang-option-code {
      color: var(--accent-primary);
    }
    .lang-option-name {
      font-size: 14px;
      flex: 1;
    }
    .lang-option-check {
      width: 16px;
      height: 16px;
      color: var(--accent-primary);
      opacity: 0;
    }
    .lang-option.current .lang-option-check {
      opacity: 1;
    }

    .timer-display {
      position: fixed;
      top: 80px; left: 50%;
      transform: translateX(-50%);
      background: var(--bg-card);
      border: 1px solid var(--accent-primary);
      border-radius: 30px;
      padding: 10px 20px;
      display: flex; align-items: center; gap: 12px;
      z-index: 100;
      opacity: 0; visibility: hidden;
      transition: var(--transition);
    }
    .timer-display.active { opacity: 1; visibility: visible; }
    .timer-display svg { width: 16px; height: 16px; color: var(--accent-primary); }
    .timer-display-time { font-family: 'JetBrains Mono', monospace; font-size: 14px; }
    .timer-display-cancel {
      background: transparent; border: none;
      color: var(--text-muted); cursor: pointer;
      padding: 4px; transition: var(--transition);
    }
    .timer-display-cancel:hover { color: #ff6b6b; }

    .hero {
      min-height: 100vh;
      display: flex; flex-direction: column;
      align-items: center; justify-content: center;
      text-align: center;
      padding: 120px 24px 80px;
    }
    .hero-content { max-width: 600px; }
    .hero h1 {
      font-family: 'Noto Serif SC', Georgia, serif;
      font-size: clamp(2.5rem, 6vw, 4rem);
      font-weight: 600;
      margin-bottom: 16px;
      background: linear-gradient(135deg, var(--text-primary) 0%, var(--text-secondary) 100%);
      -webkit-background-clip: text; -webkit-text-fill-color: transparent;
      background-clip: text;
    }
    .hero p { font-size: 18px; color: var(--text-secondary); margin-bottom: 48px; line-height: 1.8; }
    .hero-btn {
      position: relative;
      background: linear-gradient(135deg, var(--accent-primary), #8bb8ff);
      border: none;
      border-radius: 60px;
      padding: 20px 48px;
      font-size: 18px; font-weight: 500;
      color: var(--bg-deep);
      cursor: pointer;
      overflow: hidden;
      transition: var(--transition);
      box-shadow: 0 4px 24px var(--accent-glow);
    }
    .hero-btn::before {
      content: '';
      position: absolute; top: 50%; left: 50%;
      width: 0; height: 0;
      background: rgba(255, 255, 255, 0.2);
      border-radius: 50%;
      transform: translate(-50%, -50%);
      transition: width 0.6s, height 0.6s;
    }
    .hero-btn:hover { transform: translateY(-2px); box-shadow: 0 8px 32px var(--accent-glow-strong); }
    .hero-btn:hover::before { width: 300px; height: 300px; }
    .hero-btn.playing { background: linear-gradient(135deg, #ff6b6b, #ff8e8e); }

/* Shortcuts hint */
.shortcuts-hint {
      display: none;
      justify-content: center;
      gap: 24px;
      margin-top: 20px;
      opacity: 0;
      transition: opacity 0.3s ease;
    }
    .shortcuts-hint.visible {
      display: flex;
      opacity: 1;
    }
    .shortcut {
      display: flex;
      align-items: center;
      gap: 8px;
      font-size: 13px;
      color: var(--text-muted);
    }
    .shortcut kbd {
      background: var(--bg-card);
      border: 1px solid var(--border);
      border-radius: 4px;
      padding: 4px 8px;
      font-family: inherit;
      font-size: 12px;
    }

    .hero-btn-content { display: flex; align-items: center; gap: 10px; position: relative; z-index: 1; }
    .hero-btn svg { width: 24px; height: 24px; }

    main { padding: 0 0 80px; }
    .section-header { text-align: center; margin-bottom: 48px; }
    .section-title { font-family: 'Noto Serif SC', Georgia, serif; font-size: 28px; font-weight: 600; margin-bottom: 8px; }
    .section-subtitle { color: var(--text-secondary); font-size: 14px; }

    .sound-grid {
      display: grid;
      grid-template-columns: repeat(auto-fill, minmax(150px, 1fr));
      gap: 16px;
    }
    @media (min-width: 768px) {
      .sound-grid { grid-template-columns: repeat(auto-fill, minmax(160px, 1fr)); gap: 20px; }
    }

    .sound-card {
      position: relative;
      background: var(--bg-card);
      border: 1px solid var(--border);
      border-radius: 16px;
      padding: 24px 16px 20px;
      cursor: pointer;
      transition: var(--transition);
      opacity: 0;
      transform: translateY(20px);
      animation: fadeInUp 0.5s ease-out forwards;
    }
    .sound-card:nth-child(1) { animation-delay: 0ms; }
    .sound-card:nth-child(2) { animation-delay: 60ms; }
    .sound-card:nth-child(3) { animation-delay: 120ms; }
    .sound-card:nth-child(4) { animation-delay: 180ms; }
    .sound-card:nth-child(5) { animation-delay: 240ms; }
    .sound-card:nth-child(6) { animation-delay: 300ms; }
    .sound-card:nth-child(7) { animation-delay: 360ms; }
    .sound-card:nth-child(8) { animation-delay: 420ms; }
    .sound-card:nth-child(9) { animation-delay: 480ms; }
    .sound-card:nth-child(10) { animation-delay: 540ms; }
    .sound-card:nth-child(11) { animation-delay: 600ms; }
    .sound-card:nth-child(12) { animation-delay: 660ms; }
    @keyframes fadeInUp { to { opacity: 1; transform: translateY(0); } }
    .sound-card:hover { background: var(--bg-card-hover); border-color: var(--text-muted); transform: translateY(-4px); }
    .sound-card.active {
      border-color: var(--border-active);
      box-shadow: 0 0 24px var(--accent-glow), inset 0 0 20px var(--accent-glow);
    }
    .sound-card.active::before {
      content: '';
      position: absolute; inset: -1px;
      border-radius: 16px;
      background: linear-gradient(135deg, var(--accent-primary), transparent);
      opacity: 0.1;
      z-index: -1;
    }

    .sound-icon {
      width: 48px; height: 48px;
      margin: 0 auto 12px;
      display: flex; align-items: center; justify-content: center;
      color: var(--text-muted);
      transition: var(--transition);
    }
    .sound-icon svg { width: 32px; height: 32px; }
    .sound-card:hover .sound-icon { color: var(--text-secondary); }
    .sound-card.active .sound-icon { color: var(--accent-primary); }

    .sound-name {
      font-size: 14px; font-weight: 500;
      text-align: center; color: var(--text-secondary);
      margin-bottom: 4px;
      transition: var(--transition);
    }
    .sound-card:hover .sound-name { color: var(--text-primary); }
    .sound-card.active .sound-name { color: var(--text-primary); }
    .sound-desc { font-size: 11px; color: var(--text-muted); text-align: center; }

    .volume-control {
      margin-top: 16px;
      opacity: 0; max-height: 0;
      overflow: hidden;
      transition: var(--transition);
    }
    .sound-card.active .volume-control { opacity: 1; max-height: 60px; }
    .volume-slider {
      -webkit-appearance: none; appearance: none;
      width: 100%; height: 4px;
      background: var(--border);
      border-radius: 2px;
      outline: none; cursor: pointer;
    }
    .volume-slider::-webkit-slider-thumb {
      -webkit-appearance: none; appearance: none;
      width: 14px; height: 14px;
      background: var(--accent-primary);
      border-radius: 50%; cursor: pointer;
      transition: var(--transition);
      box-shadow: 0 0 8px var(--accent-glow);
    }
    .volume-slider::-webkit-slider-thumb:hover { transform: scale(1.2); box-shadow: 0 0 12px var(--accent-glow-strong); }
    .volume-slider::-moz-range-thumb { width: 14px; height: 14px; background: var(--accent-primary); border: none; border-radius: 50%; cursor: pointer; }
    .volume-value { font-size: 11px; color: var(--text-muted); text-align: center; margin-top: 8px; font-family: 'JetBrains Mono', monospace; }

    footer {
      text-align: center;
      padding: 40px 24px;
      border-top: 1px solid var(--border);
      color: var(--text-muted); font-size: 13px;
    }
    .shortcuts { display: flex; justify-content: center; gap: 24px; margin-bottom: 16px; flex-wrap: wrap; }
    .shortcut { display: flex; align-items: center; gap: 6px; }
    .shortcut kbd {
      background: var(--bg-card);
      border: 1px solid var(--border);
      border-radius: 4px;
      padding: 2px 6px;
      font-family: 'JetBrains Mono', monospace;
      font-size: 11px;
    }

    .modal-overlay {
      position: fixed; inset: 0;
      background: rgba(12, 14, 20, 0.85);
      display: flex; align-items: center; justify-content: center;
      z-index: 1000;
      opacity: 0; visibility: hidden;
      transition: var(--transition);
    }
    .modal-overlay.active { opacity: 1; visibility: visible; }
    .modal {
      background: var(--bg-card);
      border: 1px solid var(--border);
      border-radius: 20px;
      padding: 32px;
      max-width: 400px; width: 90%;
      transform: scale(0.9) translateY(20px);
      transition: var(--transition);
    }
    .modal-overlay.active .modal { transform: scale(1) translateY(0); }
    .modal-header { display: flex; align-items: center; justify-content: space-between; margin-bottom: 24px; }
    .modal-title { font-family: 'Noto Serif SC', Georgia, serif; font-size: 20px; font-weight: 600; }
    .modal-close { background: transparent; border: none; color: var(--text-muted); cursor: pointer; padding: 4px; transition: var(--transition); }
    .modal-close:hover { color: var(--text-primary); }
    .timer-options { display: grid; grid-template-columns: repeat(3, 1fr); gap: 12px; }
    .timer-option {
      background: var(--bg-deep);
      border: 1px solid var(--border);
      border-radius: 12px;
      padding: 16px 12px;
      text-align: center; cursor: pointer;
      transition: var(--transition);
    }
    .timer-option:hover, .timer-option.selected { border-color: var(--accent-primary); background: var(--accent-glow); }
    .timer-option-value { font-size: 24px; font-weight: 600; color: var(--text-primary); font-family: 'JetBrains Mono', monospace; }
    .timer-option-label { font-size: 12px; color: var(--text-muted); margin-top: 4px; }
    .timer-custom { margin-top: 16px; display: flex; gap: 12px; align-items: center; }
    .timer-custom input {
      flex: 1;
      background: var(--bg-deep);
      border: 1px solid var(--border);
      border-radius: 8px;
      padding: 12px;
      color: var(--text-primary);
      font-size: 16px; font-family: 'JetBrains Mono', monospace;
      outline: none; transition: var(--transition);
    }
    .timer-custom input:focus { border-color: var(--accent-primary); }
    .timer-custom button {
      background: var(--accent-primary); border: none;
      border-radius: 8px;
      padding: 12px 20px;
      color: var(--bg-deep); font-weight: 500;
      cursor: pointer; transition: var(--transition);
    }
    .timer-custom button:hover { background: #8bb8ff; }

    .toast {
      position: fixed;
      bottom: 40px; left: 50%;
      transform: translateX(-50%) translateY(100px);
      background: var(--bg-card);
      border: 1px solid var(--border);
      border-radius: 12px;
      padding: 14px 24px;
      display: flex; align-items: center; gap: 10px;
      z-index: 1001;
      opacity: 0; transition: var(--transition);
    }
    .toast.show { opacity: 1; transform: translateX(-50%) translateY(0); }
    .toast svg { width: 18px; height: 18px; color: var(--accent-primary); }
    .toast-message { font-size: 14px; color: var(--text-primary); }

    .main-content { opacity: 0; transform: translateY(40px); transition: var(--transition); }
    .main-content.visible { opacity: 1; transform: translateY(0); }

    @media (max-width: 640px) {
      .hero { padding: 100px 20px 60px; }
      .hero-btn { padding: 16px 36px; font-size: 16px; }
      .section-title { font-size: 24px; }
      .sound-grid { grid-template-columns: repeat(2, 1fr); gap: 12px; }
      .sound-card { padding: 20px 12px 16px; }
      .sound-icon svg { width: 28px; height: 28px; }
      .shortcuts { display: none; }
      .logo-text { font-size: 18px; }
    }