:root {
      --primary: #3b82f6;
      --primary-dark: #2563eb;
      --accent: #8b5cf6;
      --bg: #0b0f1a;
      --bg-card: #121826;
      --bg-elevated: #1a2234;
      --text: #f1f5f9;
      --text-muted: #94a3b8;
      --border: rgba(148, 163, 184, 0.12);
      --gradient: linear-gradient(135deg, #3b82f6 0%, #8b5cf6 100%);
      --success: #22c55e;
      --warning: #f59e0b;
      --danger: #ef4444;
    }

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

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

    a {
      text-decoration: none;
      color: inherit;
    }

    /* ========== Header ========== */
    .header {
      position: fixed;
      top: 0;
      left: 0;
      right: 0;
      z-index: 1000;
      background: rgba(11, 15, 26, 0.9);
      backdrop-filter: blur(16px);
      border-bottom: 1px solid var(--border);
    }

    .header-inner {
      max-width: 1100px;
      margin: 0 auto;
      padding: 0 24px;
      height: 64px;
      display: flex;
      align-items: center;
      justify-content: space-between;
    }

    .logo {
      display: flex;
      align-items: center;
      gap: 10px;
      font-weight: 700;
      font-size: 20px;
      letter-spacing: -0.02em;
    }

    .logo-icon {
      width: 32px;
      height: 32px;
      background: var(--gradient);
      border-radius: 10px;
      display: flex;
      align-items: center;
      justify-content: center;
      font-size: 14px;
      font-weight: 800;
      color: white;
    }

    .header-actions {
      display: flex;
      align-items: center;
      gap: 16px;
    }

    .lang-switch {
      font-size: 13px;
      color: var(--text-muted);
      cursor: pointer;
      padding: 6px 10px;
      border-radius: 6px;
      transition: background 0.2s;
    }

    .lang-switch:hover {
      background: rgba(255,255,255,0.05);
    }

    .btn {
      display: inline-flex;
      align-items: center;
      justify-content: center;
      gap: 8px;
      padding: 10px 20px;
      border-radius: 10px;
      font-size: 14px;
      font-weight: 600;
      cursor: pointer;
      border: none;
      transition: all 0.2s;
    }

    .btn-primary {
      background: var(--gradient);
      color: white;
      box-shadow: 0 4px 14px rgba(59, 130, 246, 0.35);
    }

    .btn-primary:hover {
      transform: translateY(-1px);
      box-shadow: 0 6px 20px rgba(59, 130, 246, 0.45);
    }

    .btn-outline {
      background: transparent;
      color: var(--text);
      border: 1px solid var(--border);
    }

    .btn-outline:hover {
      background: rgba(255,255,255,0.05);
      border-color: rgba(148, 163, 184, 0.25);
    }

    .btn-lg {
      padding: 16px 28px;
      font-size: 16px;
      border-radius: 12px;
      width: 100%;
    }

    .btn-apple {
      background: #000;
      color: white;
      border: 1px solid #333;
    }

    .btn-apple:hover {
      background: #111;
    }

    .btn-android {
      background: #3ddc84;
      color: #0b0f1a;
    }

    .btn-android:hover {
      background: #34c574;
    }

    .btn-google {
      background: #fff;
      color: #1f2937;
    }

    .btn-google:hover {
      background: #f3f4f6;
    }

    /* ========== Hero Download ========== */
    .download-hero {
      padding: 120px 24px 60px;
      max-width: 1100px;
      margin: 0 auto;
      text-align: center;
    }

    .download-hero h1 {
      font-size: 42px;
      font-weight: 800;
      letter-spacing: -0.03em;
      margin-bottom: 12px;
      background: linear-gradient(135deg, #fff 0%, #c7d2fe 100%);
      -webkit-background-clip: text;
      -webkit-text-fill-color: transparent;
      background-clip: text;
    }

    .download-hero .subtitle {
      font-size: 17px;
      color: var(--text-muted);
      margin-bottom: 40px;
    }

    /* ========== Download Cards ========== */
    .download-cards {
      display: grid;
      grid-template-columns: 1fr 1fr;
      gap: 24px;
      max-width: 900px;
      margin: 0 auto 60px;
    }

    .download-card {
      background: var(--bg-card);
      border: 1px solid var(--border);
      border-radius: 20px;
      padding: 36px 28px;
      text-align: center;
      transition: all 0.25s;
      position: relative;
      overflow: hidden;
    }

    .download-card:hover {
      border-color: rgba(59, 130, 246, 0.4);
      transform: translateY(-3px);
      box-shadow: 0 20px 40px rgba(0,0,0,0.25);
    }

    .download-card .platform-icon {
      width: 64px;
      height: 64px;
      margin: 0 auto 20px;
      border-radius: 16px;
      display: flex;
      align-items: center;
      justify-content: center;
      font-size: 32px;
    }

    .download-card.ios .platform-icon {
      background: linear-gradient(145deg, #1a1a1a, #333);
    }

    .download-card.android .platform-icon {
      background: linear-gradient(145deg, #1a3a2a, #0d2818);
    }

    .download-card h3 {
      font-size: 22px;
      font-weight: 700;
      margin-bottom: 8px;
    }

    .download-card .platform-desc {
      font-size: 14px;
      color: var(--text-muted);
      margin-bottom: 24px;
    }

    .download-btns {
      display: flex;
      flex-direction: column;
      gap: 12px;
    }

    .qr-hint {
      margin-top: 20px;
      font-size: 12px;
      color: var(--text-muted);
    }

    .qr-box {
      width: 120px;
      height: 120px;
      margin: 16px auto 0;
      background: #fff;
      border-radius: 12px;
      display: flex;
      align-items: center;
      justify-content: center;
      font-size: 11px;
      color: #64748b;
      border: 4px solid #e2e8f0;
    }

    /* ========== Security Notice ========== */
    .security-section {
      max-width: 900px;
      margin: 0 auto 60px;
      padding: 0 24px;
    }

    .security-card {
      background: linear-gradient(135deg, rgba(239, 68, 68, 0.08), rgba(245, 158, 11, 0.06));
      border: 1px solid rgba(239, 68, 68, 0.2);
      border-radius: 16px;
      padding: 28px 32px;
    }

    .security-card h3 {
      font-size: 18px;
      font-weight: 700;
      margin-bottom: 16px;
      display: flex;
      align-items: center;
      gap: 10px;
    }

    .security-list {
      list-style: none;
      display: flex;
      flex-direction: column;
      gap: 12px;
    }

    .security-list li {
      font-size: 14px;
      color: var(--text-muted);
      display: flex;
      align-items: flex-start;
      gap: 10px;
      line-height: 1.5;
    }

    .security-list li::before {
      content: "⚠";
      flex-shrink: 0;
      font-size: 14px;
    }

    .security-list strong {
      color: var(--text);
    }

    .security-links {
      margin-top: 20px;
      display: flex;
      gap: 20px;
      flex-wrap: wrap;
    }

    .security-links a {
      font-size: 14px;
      color: var(--primary);
      font-weight: 500;
    }

    .security-links a:hover {
      text-decoration: underline;
    }

    /* ========== Features ========== */
    .features-section {
      max-width: 1100px;
      margin: 0 auto;
      padding: 40px 24px 80px;
    }

    .section-title {
      text-align: center;
      font-size: 28px;
      font-weight: 800;
      margin-bottom: 36px;
      letter-spacing: -0.02em;
    }

    .features-grid {
      display: grid;
      grid-template-columns: repeat(2, 1fr);
      gap: 20px;
    }

    .feature-card {
      background: var(--bg-card);
      border: 1px solid var(--border);
      border-radius: 16px;
      padding: 28px;
      display: flex;
      gap: 18px;
      transition: all 0.2s;
    }

    .feature-card:hover {
      border-color: rgba(59, 130, 246, 0.3);
    }

    .feature-icon {
      width: 48px;
      height: 48px;
      background: rgba(59, 130, 246, 0.12);
      border-radius: 12px;
      display: flex;
      align-items: center;
      justify-content: center;
      font-size: 22px;
      flex-shrink: 0;
    }

    .feature-content h4 {
      font-size: 16px;
      font-weight: 600;
      margin-bottom: 6px;
    }

    .feature-content p {
      font-size: 13px;
      color: var(--text-muted);
      line-height: 1.5;
    }

    /* ========== Steps ========== */
    .steps-section {
      max-width: 900px;
      margin: 0 auto 80px;
      padding: 0 24px;
    }

    .steps-grid {
      display: grid;
      grid-template-columns: repeat(3, 1fr);
      gap: 20px;
    }

    .step-card {
      background: var(--bg-card);
      border: 1px solid var(--border);
      border-radius: 16px;
      padding: 24px;
      text-align: center;
      position: relative;
    }

    .step-num {
      width: 36px;
      height: 36px;
      background: var(--gradient);
      border-radius: 50%;
      display: flex;
      align-items: center;
      justify-content: center;
      font-size: 16px;
      font-weight: 700;
      margin: 0 auto 16px;
      color: white;
    }

    .step-card h4 {
      font-size: 15px;
      font-weight: 600;
      margin-bottom: 8px;
    }

    .step-card p {
      font-size: 13px;
      color: var(--text-muted);
    }

    /* ========== Verify ========== */
    .verify-section {
      max-width: 900px;
      margin: 0 auto 80px;
      padding: 0 24px;
    }

    .verify-card {
      background: var(--bg-card);
      border: 1px solid var(--border);
      border-radius: 16px;
      padding: 32px;
    }

    .verify-card h3 {
      font-size: 18px;
      font-weight: 700;
      margin-bottom: 20px;
      display: flex;
      align-items: center;
      gap: 10px;
    }

    .verify-steps {
      display: flex;
      flex-direction: column;
      gap: 16px;
    }

    .verify-step {
      display: flex;
      gap: 14px;
      align-items: flex-start;
    }

    .verify-step .num {
      width: 28px;
      height: 28px;
      background: rgba(59, 130, 246, 0.15);
      color: var(--primary);
      border-radius: 50%;
      display: flex;
      align-items: center;
      justify-content: center;
      font-size: 13px;
      font-weight: 700;
      flex-shrink: 0;
    }

    .verify-step p {
      font-size: 14px;
      color: var(--text-muted);
      padding-top: 3px;
    }

    .verify-step strong {
      color: var(--text);
    }

    /* ========== Footer ========== */
    .footer {
      border-top: 1px solid var(--border);
      padding: 40px 24px;
      text-align: center;
    }

    .footer-inner {
      max-width: 1100px;
      margin: 0 auto;
    }

    .footer p {
      font-size: 13px;
      color: var(--text-muted);
      margin-bottom: 8px;
    }

    .footer a {
      color: var(--primary);
    }

    .footer a:hover {
      text-decoration: underline;
    }

    .official-badge {
      display: inline-flex;
      align-items: center;
      gap: 6px;
      background: rgba(34, 197, 94, 0.1);
      color: var(--success);
      font-size: 13px;
      font-weight: 600;
      padding: 6px 14px;
      border-radius: 20px;
      margin-top: 12px;
    }

    /* ========== Responsive ========== */
    @media (max-width: 768px) {
      .download-hero h1 {
        font-size: 28px;
      }

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

      .features-grid {
        grid-template-columns: 1fr;
      }

      .steps-grid {
        grid-template-columns: 1fr;
      }
    }