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

      :root {
        --primary: #6366f1;
        --primary-dark: #4f46e5;
        --primary-light: #8b5cf6;
        --secondary: #10b981;
        --secondary-dark: #059669;
        --accent: #f59e0b;
        --dark: #1e293b;
        --dark-light: #334155;
        --dark-lighter: #475569;
        --light: #f8fafc;
        --light-dark: #e2e8f0;
        --border: #e2e8f0;
        --text: #0f172a;
        --text-muted: #64748b;
        --text-light: #94a3b8;
        --shadow: rgba(0, 0, 0, 0.1);
        --shadow-lg: rgba(0, 0, 0, 0.15);
        --shadow-xl: rgba(0, 0, 0, 0.25);
        --bg-gradient-1: #ffffff;
        --bg-gradient-2: #f8fafc;
        --glass-bg: rgba(255, 255, 255, 0.25);
        --glass-border: rgba(255, 255, 255, 0.18);
        --blur: blur(10px);
        --animation-speed: 0.3s;
        --animation-timing: cubic-bezier(0.4, 0, 0.2, 1);
      }

      [data-theme="dark"] {
        --primary: #818cf8;
        --primary-dark: #6366f1;
        --primary-light: #a78bfa;
        --secondary: #34d399;
        --secondary-dark: #10b981;
        --accent: #fbbf24;
        --dark: #0f172a;
        --dark-light: #1e293b;
        --dark-lighter: #334155;
        --light: #0f172a;
        --light-dark: #1e293b;
        --border: #334155;
        --text: #f1f5f9;
        --text-muted: #cbd5e1;
        --text-light: #94a3b8;
        --shadow: rgba(0, 0, 0, 0.4);
        --shadow-lg: rgba(0, 0, 0, 0.5);
        --shadow-xl: rgba(0, 0, 0, 0.6);
        --bg-gradient-1: #0f172a;
        --bg-gradient-2: #020617;
        --glass-bg: rgba(15, 23, 42, 0.25);
        --glass-border: rgba(255, 255, 255, 0.1);
      }

      body {
        font-family: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, sans-serif;
        line-height: 1.6;
        color: var(--text);
        background: linear-gradient(135deg, var(--bg-gradient-1) 0%, var(--bg-gradient-2) 100%);
        min-height: 100vh;
        position: relative;
        overflow-x: hidden;
        animation: fadeIn 1s ease-out;
      }

      @keyframes fadeIn {
        from { opacity: 0; transform: translateY(20px); }
        to { opacity: 1; transform: translateY(0); }
      }

      body::before {
        content: "";
        position: fixed;
        top: 0;
        left: 0;
        width: 100%;
        height: 100%;
        background:
          radial-gradient(circle at 20% 50%, rgba(99, 102, 241, 0.15) 0%, transparent 50%),
          radial-gradient(circle at 80% 80%, rgba(139, 92, 246, 0.15) 0%, transparent 50%),
          radial-gradient(circle at 40% 20%, rgba(236, 72, 153, 0.1) 0%, transparent 50%),
          radial-gradient(circle at 60% 30%, rgba(16, 185, 129, 0.1) 0%, transparent 50%);
        z-index: -2;
        pointer-events: none;
        animation: float 20s ease-in-out infinite;
      }

      @keyframes float {
        0%, 100% { transform: translateY(0px) rotate(0deg); }
        33% { transform: translateY(-10px) rotate(1deg); }
        66% { transform: translateY(10px) rotate(-1deg); }
      }

      /* Animated background shapes */
      body::after {
        content: "";
        position: fixed;
        top: 0;
        left: 0;
        width: 100%;
        height: 100%;
        background-image:
          radial-gradient(circle at 25% 25%, rgba(99, 102, 241, 0.05) 0%, transparent 50%),
          radial-gradient(circle at 75% 75%, rgba(16, 185, 129, 0.05) 0%, transparent 50%),
          radial-gradient(circle at 50% 50%, rgba(245, 158, 11, 0.03) 0%, transparent 50%);
        z-index: -1;
        pointer-events: none;
        animation: pulse 15s ease-in-out infinite;
      }

      @keyframes pulse {
        0%, 100% { opacity: 0.5; transform: scale(1); }
        50% { opacity: 1; transform: scale(1.05); }
      }

      [data-theme="dark"] body::before {
        background: radial-gradient(
            circle at 20% 50%,
            rgba(99, 102, 241, 0.08) 0%,
            transparent 50%
          ),
          radial-gradient(
            circle at 80% 80%,
            rgba(139, 92, 246, 0.08) 0%,
            transparent 50%
          ),
          radial-gradient(
            circle at 40% 20%,
            rgba(236, 72, 153, 0.05) 0%,
            transparent 50%
          ),
          radial-gradient(
            circle at 60% 30%,
            rgba(52, 211, 153, 0.05) 0%,
            transparent 50%
          );
      }

      .container {
        max-width: 900px;
        margin: 0 auto;
        padding: 2rem 1rem 4rem;
      }

      /* Navigation Header */
      .nav-header {
        background: var(--glass-bg);
        backdrop-filter: var(--blur);
        border-bottom: 1px solid var(--glass-border);
        position: sticky;
        top: 0;
        z-index: 1000;
        box-shadow: 0 2px 20px var(--shadow);
        transition: all var(--animation-speed) var(--animation-timing);
        animation: slideDown 0.8s ease-out;
      }

      @keyframes slideDown {
        from { transform: translateY(-100%); opacity: 0; }
        to { transform: translateY(0); opacity: 1; }
      }

      .nav-header:hover {
        background: rgba(255, 255, 255, 0.3);
        backdrop-filter: blur(20px);
        box-shadow: 0 4px 30px var(--shadow-lg);
      }

      [data-theme="dark"] .nav-header {
        background: var(--glass-bg);
        border-color: var(--glass-border);
      }

      [data-theme="dark"] .nav-header:hover {
        background: rgba(15, 23, 42, 0.3);
      }

      .nav-container {
        max-width: 1200px;
        margin: 0 auto;
        padding: 1rem 2rem;
        display: flex;
        justify-content: space-between;
        align-items: center;
      }

      .nav-brand .brand-link {
        text-decoration: none;
        color: var(--primary);
        font-weight: 700;
        font-size: 1.5rem;
        display: flex;
        align-items: center;
        gap: 0.5rem;
      }

      .brand-icon {
        width: 44px;
        height: 44px;
        object-fit: cover;
        border-radius: 8px;
        display: inline-block;
        border: 2px solid rgba(0,0,0,0.06);
        background: white;
      }

      .nav-brand .brand-text {
        background: linear-gradient(135deg, var(--primary), var(--secondary));
        -webkit-background-clip: text;
        -webkit-text-fill-color: transparent;
        background-clip: text;
      }

      .nav-controls {
        display: flex;
        align-items: center;
        gap: 1rem;
      }

      .nav-home-btn {
        display: flex;
        align-items: center;
        gap: 0.5rem;
        padding: 0.5rem 1rem;
        border-radius: 12px;
        background: var(--glass-bg);
        color: var(--text);
        text-decoration: none;
        font-weight: 500;
        font-size: 0.9rem;
        border: 1px solid var(--glass-border);
        transition: all var(--animation-speed) var(--animation-timing);
        backdrop-filter: var(--blur);
        position: relative;
        overflow: hidden;
      }

      .nav-home-btn::before {
        content: "";
        position: absolute;
        top: 0;
        left: -100%;
        width: 100%;
        height: 100%;
        background: linear-gradient(90deg, transparent, rgba(99, 102, 241, 0.1), transparent);
        transition: left 0.6s ease;
      }

      .nav-home-btn:hover::before {
        left: 100%;
      }

      .nav-home-btn:hover {
        background: var(--primary);
        color: white;
        transform: translateY(-2px);
        box-shadow: 0 8px 25px rgba(99, 102, 241, 0.3);
        border-color: var(--primary);
      }

      [data-theme="dark"] .nav-home-btn {
        background: var(--glass-bg);
        color: var(--text);
        border-color: var(--glass-border);
      }

      .theme-toggle {
        width: 42px;
        height: 42px;
        border-radius: 50%;
        border: 2px solid var(--glass-border);
        background: var(--glass-bg);
        backdrop-filter: var(--blur);
        cursor: pointer;
        display: flex;
        align-items: center;
        justify-content: center;
        font-size: 20px;
        transition: all var(--animation-speed) var(--animation-timing);
        position: relative;
        overflow: hidden;
        box-shadow: 0 4px 15px var(--shadow);
      }

      .theme-toggle::before {
        content: "";
        position: absolute;
        top: 50%;
        left: 50%;
        width: 0;
        height: 0;
        background: radial-gradient(circle, rgba(99, 102, 241, 0.2), transparent);
        border-radius: 50%;
        transform: translate(-50%, -50%);
        transition: all 0.6s ease;
      }

      .theme-toggle:hover::before {
        width: 60px;
        height: 60px;
      }

      .theme-toggle:hover {
        border-color: var(--primary);
        transform: rotate(180deg) scale(1.1);
        box-shadow: 0 8px 25px rgba(99, 102, 241, 0.3);
      }

      .theme-toggle:active {
        transform: rotate(180deg) scale(0.95);
      }

      .header {
        text-align: center;
        margin-bottom: 4rem;
        padding: 4rem 0 2rem;
        position: relative;
        overflow: hidden;
        animation: fadeInUp 1s ease-out 0.2s both;
      }

      .header::before {
        content: "";
        position: absolute;
        top: 50%;
        left: 50%;
        transform: translate(-50%, -50%);
        width: 200%;
        height: 200%;
        background: radial-gradient(circle, rgba(99, 102, 241, 0.05) 0%, transparent 70%);
        animation: rotate 20s linear infinite;
        z-index: -1;
      }

      @keyframes rotate {
        from { transform: translate(-50%, -50%) rotate(0deg); }
        to { transform: translate(-50%, -50%) rotate(360deg); }
      }

      .header h1 {
        font-size: 3.5rem;
        font-weight: 900;
        background: linear-gradient(135deg, var(--primary), var(--primary-light), var(--secondary), var(--accent));
        -webkit-background-clip: text;
        -webkit-text-fill-color: transparent;
        background-clip: text;
        margin-bottom: 2rem;
        line-height: 1.1;
        position: relative;
        letter-spacing: -0.02em;
        animation: textGlow 3s ease-in-out infinite alternate;
      }

      .header h1::after {
        content: "✨";
        position: absolute;
        top: -10px;
        right: -40px;
        font-size: 1.5rem;
        animation: sparkle 2s ease-in-out infinite;
      }

      .header-subtitle {
        font-size: 1.4rem;
        color: var(--text-muted);
        font-weight: 500;
        margin-bottom: 3rem;
        position: relative;
        animation: fadeInUp 1s ease-out 0.3s both;
      }

      .header-subtitle::before {
        content: "🔒";
        margin-right: 0.5rem;
        vertical-align: middle;
      }

      .features-highlights {
        display: flex;
        justify-content: center;
        gap: 2rem;
        margin-bottom: 3rem;
        flex-wrap: wrap;
        animation: fadeInUp 1s ease-out 0.4s both;
      }

      .feature-highlight {
        display: flex;
        align-items: center;
        gap: 0.5rem;
        padding: 0.75rem 1.5rem;
        background: var(--glass-bg);
        backdrop-filter: var(--blur);
        border-radius: 50px;
        border: 1px solid var(--glass-border);
        font-size: 0.9rem;
        font-weight: 600;
        color: var(--text);
        transition: all var(--animation-speed) var(--animation-timing);
        animation: bounceIn 0.8s ease-out both;
        animation-delay: calc(var(--highlight-index, 0) * 0.1s);
      }

      @keyframes bounceIn {
        0% {
          opacity: 0;
          transform: scale(0.3);
        }
        50% {
          opacity: 1;
          transform: scale(1.05);
        }
        70% {
          transform: scale(0.9);
        }
        100% {
          opacity: 1;
          transform: scale(1);
        }
      }

      .feature-highlight:hover {
        transform: translateY(-3px);
        box-shadow: 0 8px 25px var(--shadow-lg);
        background: rgba(255, 255, 255, 0.3);
        border-color: var(--primary);
      }

      .feature-highlight .icon {
        font-size: 1.2rem;
        color: var(--primary);
      }

      [data-theme="dark"] .feature-highlight {
        background: var(--glass-bg);
        border-color: var(--glass-border);
      }

      [data-theme="dark"] .feature-highlight:hover {
        background: rgba(15, 23, 42, 0.3);
      }

      .header-description {
        max-width: 1000px;
        margin: 0 auto;
        position: relative;
        animation: fadeInUp 1s ease-out 0.5s both;
      }

      .description-section {
        margin-bottom: 2rem;
        padding: 2rem;
        background: var(--glass-bg);
        backdrop-filter: var(--blur);
        border-radius: 20px;
        border: 1px solid var(--glass-border);
        position: relative;
        transition: all var(--animation-speed) var(--animation-timing);
        animation: slideInFromBottom 1s ease-out both;
        animation-delay: calc(var(--desc-index, 0) * 0.2s);
      }

      .description-section:hover {
        transform: translateY(-5px);
        box-shadow: 0 15px 35px var(--shadow-lg);
        background: rgba(255, 255, 255, 0.4);
        border-color: var(--primary);
      }

      .description-section::before {
        content: "";
        position: absolute;
        top: 0;
        left: 0;
        width: 4px;
        height: 100%;
        background: linear-gradient(180deg, var(--primary), var(--secondary));
        border-radius: 2px 0 0 2px;
      }

      .description-section h3 {
        font-size: 1.3rem;
        font-weight: 700;
        color: var(--primary);
        margin-bottom: 1rem;
        display: flex;
        align-items: center;
        gap: 0.5rem;
      }

      .description-section h3 .icon {
        font-size: 1.5rem;
      }

      .description-section p {
        font-size: 1.1rem;
        color: var(--text-muted);
        line-height: 1.7;
        margin: 0;
      }

      [data-theme="dark"] .description-section {
        background: var(--glass-bg);
        border-color: var(--glass-border);
      }

      [data-theme="dark"] .description-section:hover {
        background: rgba(15, 23, 42, 0.4);
      }

      @keyframes countUp {
        from {
          opacity: 0;
          transform: translateY(20px);
        }
        to {
          opacity: 1;
          transform: translateY(0);
        }
      }

      .extension-preview {
        text-align: center;
        margin: 4rem 0;
        position: relative;
        animation: fadeInUp 1s ease-out 0.6s both;
      }

      .extension-screenshot {
        max-width: 100%;
        height: auto;
        border-radius: 20px;
        box-shadow:
          0 20px 40px var(--shadow),
          0 0 0 1px var(--glass-border);
        border: 2px solid var(--glass-border);
        transition: all var(--animation-speed) var(--animation-timing);
        position: relative;
        backdrop-filter: var(--blur);
        animation: float 6s ease-in-out infinite;
      }

      .extension-screenshot::before {
        content: "";
        position: absolute;
        top: -2px;
        left: -2px;
        right: -2px;
        bottom: -2px;
        background: linear-gradient(45deg, var(--primary), var(--secondary), var(--accent));
        border-radius: 22px;
        z-index: -1;
        opacity: 0;
        transition: opacity var(--animation-speed) ease;
      }

      .extension-screenshot:hover::before {
        opacity: 0.3;
      }

      .extension-screenshot:hover {
        transform: translateY(-8px) scale(1.02);
        box-shadow:
          0 30px 60px var(--shadow-lg),
          0 0 0 1px var(--primary),
          0 0 30px rgba(99, 102, 241, 0.2);
      }

      .image-caption {
        margin-top: 2rem;
        font-size: 1rem;
        color: var(--text-muted);
        font-style: italic;
        font-weight: 500;
        animation: fadeIn 1s ease-out 0.8s both;
        position: relative;
      }

      .image-caption::before {
        content: "✨";
        position: absolute;
        left: -25px;
        top: 50%;
        transform: translateY(-50%);
        animation: sparkle 2s ease-in-out infinite;
      }

      @keyframes sparkle {
        0%, 100% { opacity: 0.5; transform: translateY(-50%) scale(1); }
        50% { opacity: 1; transform: translateY(-50%) scale(1.2); }
      }

      .extension-card {
        background: var(--glass-bg);
        backdrop-filter: var(--blur);
        border-radius: 24px;
        padding: 3rem;
        box-shadow:
          0 10px 30px var(--shadow),
          0 0 0 1px var(--glass-border);
        margin-bottom: 3rem;
        border: 1px solid var(--glass-border);
        position: relative;
        overflow: hidden;
        transition: all var(--animation-speed) var(--animation-timing);
        animation: slideInFromBottom 1s ease-out both;
        animation-delay: calc(var(--card-index, 0) * 0.2s);
      }

      @keyframes slideInFromBottom {
        from {
          opacity: 0;
          transform: translateY(50px);
        }
        to {
          opacity: 1;
          transform: translateY(0);
        }
      }

      .extension-card::before {
        content: "";
        position: absolute;
        top: 0;
        left: 0;
        right: 0;
        height: 4px;
        background: linear-gradient(90deg, var(--primary), var(--secondary), var(--accent));
        border-radius: 24px 24px 0 0;
        animation: shimmer 3s ease-in-out infinite;
      }

      @keyframes shimmer {
        0% { background-position: -200% 0; }
        100% { background-position: 200% 0; }
      }

      .extension-card:hover {
        transform: translateY(-5px);
        box-shadow:
          0 20px 50px var(--shadow-lg),
          0 0 0 1px var(--primary),
          0 0 40px rgba(99, 102, 241, 0.1);
        background: rgba(255, 255, 255, 0.3);
      }

      [data-theme="dark"] .extension-card {
        background: var(--glass-bg);
        border-color: var(--glass-border);
      }

      [data-theme="dark"] .extension-card:hover {
        background: rgba(15, 23, 42, 0.3);
      }

      .extension-card h2 {
        font-size: 2.2rem;
        font-weight: 700;
        color: var(--primary);
        margin-bottom: 1.5rem;
        display: flex;
        align-items: center;
        gap: 0.5rem;
      }

      .extension-card p {
        margin-bottom: 2rem;
        color: var(--text-muted);
        font-size: 1.1rem;
        line-height: 1.7;
      }

      .steps {
        list-style: none;
        counter-reset: step-counter;
        margin-bottom: 2rem;
      }

      .steps li {
        counter-increment: step-counter;
        margin-bottom: 1.5rem;
        padding: 1.5rem 2rem 1.5rem 4rem;
        position: relative;
        background: var(--glass-bg);
        backdrop-filter: var(--blur);
        border-radius: 16px;
        border: 1px solid var(--glass-border);
        transition: all var(--animation-speed) var(--animation-timing);
        animation: slideInFromLeft 0.8s ease-out both;
        animation-delay: calc(var(--step-index, 0) * 0.1s);
      }

      @keyframes slideInFromLeft {
        from {
          opacity: 0;
          transform: translateX(-30px);
        }
        to {
          opacity: 1;
          transform: translateX(0);
        }
      }

      .steps li:hover {
        transform: translateX(8px);
        box-shadow:
          0 8px 25px var(--shadow-lg),
          0 0 0 1px var(--primary);
        background: rgba(255, 255, 255, 0.4);
        border-color: var(--primary);
      }

      .steps li::before {
        content: counter(step-counter);
        position: absolute;
        left: -15px;
        top: 50%;
        transform: translateY(-50%);
        width: 2.5rem;
        height: 2.5rem;
        background: linear-gradient(135deg, var(--primary), var(--primary-dark));
        color: white;
        border-radius: 50%;
        display: flex;
        align-items: center;
        justify-content: center;
        font-weight: 700;
        font-size: 1rem;
        box-shadow: 0 4px 15px rgba(99, 102, 241, 0.3);
        transition: all var(--animation-speed) ease;
        z-index: 1;
      }

      .steps li:hover::before {
        transform: translateY(-50%) scale(1.1);
        box-shadow: 0 6px 20px rgba(99, 102, 241, 0.4);
      }

      [data-theme="dark"] .steps li {
        background: var(--glass-bg);
        border-color: var(--glass-border);
      }

      [data-theme="dark"] .steps li:hover {
        background: rgba(15, 23, 42, 0.4);
      }

      .download-btn {
        display: inline-flex;
        align-items: center;
        gap: 0.5rem;
        background: linear-gradient(135deg, var(--primary), var(--primary-dark));
        color: white;
        padding: 1rem 2rem;
        border-radius: 16px;
        text-decoration: none;
        font-weight: 600;
        font-size: 1.1rem;
        transition: all var(--animation-speed) var(--animation-timing);
        box-shadow:
          0 8px 20px rgba(99, 102, 241, 0.4),
          0 0 0 1px rgba(255, 255, 255, 0.1);
        position: relative;
        overflow: hidden;
        border: none;
        animation: pulseGlow 2s ease-in-out infinite;
      }

      @keyframes pulseGlow {
        0%, 100% { box-shadow: 0 8px 20px rgba(99, 102, 241, 0.4), 0 0 0 1px rgba(255, 255, 255, 0.1); }
        50% { box-shadow: 0 8px 30px rgba(99, 102, 241, 0.6), 0 0 0 1px rgba(255, 255, 255, 0.2); }
      }

      .download-btn::before {
        content: "";
        position: absolute;
        top: 0;
        left: -100%;
        width: 100%;
        height: 100%;
        background: linear-gradient(90deg, transparent, rgba(255, 255, 255, 0.2), transparent);
        transition: left 0.6s ease;
      }

      .download-btn:hover::before {
        left: 100%;
      }

      .download-btn:hover {
        transform: translateY(-4px) scale(1.02);
        box-shadow:
          0 15px 35px rgba(99, 102, 241, 0.5),
          0 0 0 1px rgba(255, 255, 255, 0.2),
          0 0 40px rgba(99, 102, 241, 0.3);
      }

      .download-btn:active {
        transform: translateY(-2px) scale(0.98);
      }

      .features-grid {
        display: grid;
        grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
        gap: 1.5rem;
        margin-top: 2rem;
      }

      .feature-item {
        display: flex;
        align-items: flex-start;
        gap: 1rem;
        padding: 1.5rem;
        background: var(--glass-bg);
        backdrop-filter: var(--blur);
        border-radius: 16px;
        border: 1px solid var(--glass-border);
        transition: all var(--animation-speed) var(--animation-timing);
        position: relative;
        overflow: hidden;
        animation: fadeInScale 0.8s ease-out both;
        animation-delay: calc(var(--feature-index, 0) * 0.1s);
      }

      @keyframes fadeInScale {
        from {
          opacity: 0;
          transform: scale(0.9);
        }
        to {
          opacity: 1;
          transform: scale(1);
        }
      }

      .feature-item::before {
        content: "";
        position: absolute;
        top: 0;
        left: 0;
        width: 4px;
        height: 100%;
        background: linear-gradient(180deg, var(--primary), var(--secondary));
        opacity: 0;
        transition: opacity var(--animation-speed) ease;
      }

      .feature-item:hover::before {
        opacity: 1;
      }

      .feature-item:hover {
        transform: translateY(-5px) scale(1.02);
        box-shadow:
          0 12px 30px var(--shadow-lg),
          0 0 0 1px var(--primary);
        background: rgba(255, 255, 255, 0.4);
        border-color: var(--primary);
      }

      [data-theme="dark"] .feature-item {
        background: var(--glass-bg);
        border-color: var(--glass-border);
      }

      [data-theme="dark"] .feature-item:hover {
        background: rgba(15, 23, 42, 0.4);
      }

      .feature-icon {
        font-size: 2rem;
        flex-shrink: 0;
        margin-top: 0.25rem;
      }

      .feature-content h3 {
        font-size: 1.1rem;
        font-weight: 600;
        color: var(--text);
        margin-bottom: 0.5rem;
      }

      .feature-content p {
        font-size: 0.95rem;
        color: var(--text-muted);
        margin: 0;
        line-height: 1.5;
      }

      .usage-guide {
        margin-bottom: 2rem;
      }

      .usage-step {
        display: flex;
        align-items: flex-start;
        gap: 1rem;
        margin-bottom: 1.5rem;
        padding: 1.5rem;
        background: var(--glass-bg);
        backdrop-filter: var(--blur);
        border-radius: 16px;
        border: 1px solid var(--glass-border);
        transition: all var(--animation-speed) var(--animation-timing);
        animation: slideInFromRight 0.8s ease-out both;
        animation-delay: calc(var(--usage-index, 0) * 0.15s);
      }

      @keyframes slideInFromRight {
        from {
          opacity: 0;
          transform: translateX(30px);
        }
        to {
          opacity: 1;
          transform: translateX(0);
        }
      }

      .usage-step:hover {
        transform: translateX(8px);
        box-shadow:
          0 8px 25px var(--shadow-lg),
          0 0 0 1px var(--primary);
        background: rgba(255, 255, 255, 0.4);
        border-color: var(--primary);
      }

      [data-theme="dark"] .usage-step {
        background: var(--glass-bg);
        border-color: var(--glass-border);
      }

      [data-theme="dark"] .usage-step:hover {
        background: rgba(15, 23, 42, 0.4);
      }

      .step-number {
        width: 2.5rem;
        height: 2.5rem;
        background: linear-gradient(135deg, var(--primary), var(--primary-dark));
        color: white;
        border-radius: 50%;
        display: flex;
        align-items: center;
        justify-content: center;
        font-weight: 700;
        font-size: 1rem;
        flex-shrink: 0;
        box-shadow: 0 4px 15px rgba(99, 102, 241, 0.3);
        transition: all var(--animation-speed) ease;
        position: relative;
        overflow: hidden;
      }

      .step-number::before {
        content: "";
        position: absolute;
        top: 50%;
        left: 50%;
        width: 0;
        height: 0;
        background: radial-gradient(circle, rgba(255, 255, 255, 0.3), transparent);
        border-radius: 50%;
        transform: translate(-50%, -50%);
        transition: all 0.4s ease;
      }

      .usage-step:hover .step-number::before {
        width: 40px;
        height: 40px;
      }

      .usage-step:hover .step-number {
        transform: scale(1.1);
        box-shadow: 0 6px 20px rgba(99, 102, 241, 0.4);
      }

      .step-content h3 {
        font-size: 1.1rem;
        font-weight: 600;
        color: var(--text);
        margin-bottom: 0.5rem;
      }

      .step-content p {
        font-size: 0.95rem;
        color: var(--text-muted);
        margin: 0;
        line-height: 1.5;
      }

      .tips-section {
        background: linear-gradient(135deg, var(--primary) 0%, var(--secondary) 50%, var(--accent) 100%);
        color: white;
        padding: 2rem;
        border-radius: 16px;
        margin-top: 2rem;
        position: relative;
        overflow: hidden;
        animation: gradientShift 4s ease-in-out infinite;
      }

      @keyframes gradientShift {
        0%, 100% { background-position: 0% 50%; }
        50% { background-position: 100% 50%; }
      }

      .tips-section::before {
        content: "";
        position: absolute;
        top: 0;
        left: 0;
        right: 0;
        bottom: 0;
        background: url('data:image/svg+xml,<svg xmlns="http://www.w3.org/2000/svg" viewBox="0 0 100 100"><defs><pattern id="sparkles" width="20" height="20" patternUnits="userSpaceOnUse"><circle cx="10" cy="10" r="1" fill="rgba(255,255,255,0.1)"/><circle cx="5" cy="15" r="0.5" fill="rgba(255,255,255,0.05)"/></pattern></defs><rect width="100" height="100" fill="url(%23sparkles)"/></svg>');
        opacity: 0.3;
        animation: twinkle 3s ease-in-out infinite;
      }

      @keyframes twinkle {
        0%, 100% { opacity: 0.3; }
        50% { opacity: 0.6; }
      }

      .tips-section h3 {
        font-size: 1.3rem;
        font-weight: 700;
        margin-bottom: 1rem;
        display: flex;
        align-items: center;
        gap: 0.5rem;
      }

      .tips-section ul {
        list-style: none;
        padding: 0;
      }

      .tips-section li {
        margin-bottom: 0.8rem;
        padding-left: 1rem;
        position: relative;
      }

      .tips-section li::before {
        content: "✓";
        position: absolute;
        left: 0;
        color: rgba(255, 255, 255, 0.8);
        font-weight: bold;
      }

      .tips-section strong {
        color: rgba(255, 255, 255, 0.9);
      }

      /* Final CTA Section */
      .final-cta {
        background: linear-gradient(135deg, var(--primary) 0%, var(--primary-dark) 50%, var(--secondary) 100%);
        padding: 4rem 0;
        margin-top: 2rem;
        position: relative;
        overflow: hidden;
        animation: gradientFlow 6s ease-in-out infinite;
      }

      @keyframes gradientFlow {
        0%, 100% {
          background-position: 0% 50%;
          filter: hue-rotate(0deg);
        }
        50% {
          background-position: 100% 50%;
          filter: hue-rotate(10deg);
        }
      }

      .final-cta::before {
        content: "";
        position: absolute;
        top: 0;
        left: 0;
        right: 0;
        bottom: 0;
        background:
          radial-gradient(circle at 30% 20%, rgba(255, 255, 255, 0.1) 0%, transparent 50%),
          radial-gradient(circle at 70% 80%, rgba(255, 255, 255, 0.1) 0%, transparent 50%),
          url('data:image/svg+xml,<svg xmlns="http://www.w3.org/2000/svg" viewBox="0 0 100 100"><defs><pattern id="particles" width="10" height="10" patternUnits="userSpaceOnUse"><circle cx="5" cy="5" r="0.5" fill="rgba(255,255,255,0.05)"/></pattern></defs><rect width="100" height="100" fill="url(%23particles)"/></svg>');
        animation: particleFloat 8s ease-in-out infinite;
      }

      @keyframes particleFloat {
        0%, 100% { transform: translateY(0px) rotate(0deg); }
        25% { transform: translateY(-5px) rotate(90deg); }
        50% { transform: translateY(-10px) rotate(180deg); }
        75% { transform: translateY(-5px) rotate(270deg); }
      }

      .cta-content {
        text-align: center;
        color: white;
        position: relative;
        z-index: 1;
      }

      .cta-content h2 {
        font-size: 2.5rem;
        font-weight: 800;
        margin-bottom: 1rem;
        text-shadow: 0 2px 4px rgba(0, 0, 0, 0.3);
      }

      .cta-content p {
        font-size: 1.2rem;
        margin-bottom: 2rem;
        opacity: 0.9;
        max-width: 600px;
        margin-left: auto;
        margin-right: auto;
      }

      .cta-buttons {
        display: flex;
        gap: 1rem;
        justify-content: center;
        flex-wrap: wrap;
      }

      .cta-primary-btn {
        display: inline-flex;
        align-items: center;
        gap: 0.5rem;
        background: white;
        color: var(--primary);
        padding: 1rem 2rem;
        border-radius: 12px;
        text-decoration: none;
        font-weight: 700;
        font-size: 1.1rem;
        transition: all 0.3s ease;
        box-shadow: 0 8px 20px rgba(0, 0, 0, 0.2);
        border: 2px solid white;
      }

      .cta-primary-btn:hover {
        transform: translateY(-3px);
        box-shadow: 0 12px 30px rgba(0, 0, 0, 0.3);
        background: rgba(255, 255, 255, 0.95);
      }

      .cta-secondary-btn {
        display: inline-flex;
        align-items: center;
        gap: 0.5rem;
        background: transparent;
        color: white;
        padding: 1rem 2rem;
        border-radius: 12px;
        text-decoration: none;
        font-weight: 600;
        font-size: 1.1rem;
        transition: all 0.3s ease;
        border: 2px solid rgba(255, 255, 255, 0.3);
      }

      .cta-secondary-btn:hover {
        background: rgba(255, 255, 255, 0.1);
        border-color: rgba(255, 255, 255, 0.5);
        transform: translateY(-2px);
      }

      .back-link {
        display: inline-block;
        color: var(--primary);
        text-decoration: none;
        font-weight: 500;
        margin-top: 2rem;
      }

      .back-link:hover {
        text-decoration: underline;
      }

      @media (max-width: 768px) {
        .nav-container {
          padding: 1rem;
        }

        .nav-brand .brand-text {
          font-size: 1.2rem;
        }

        .nav-home-btn {
          padding: 0.4rem 0.8rem;
          font-size: 0.8rem;
        }

        .header h1 {
          font-size: 2.5rem;
        }

        .header-subtitle {
          font-size: 1.1rem;
        }

        .features-highlights {
          gap: 1rem;
        }

        .feature-highlight {
          padding: 0.5rem 1rem;
          font-size: 0.8rem;
        }

        .description-section {
          padding: 1.5rem;
        }

        .description-section h3 {
          font-size: 1.1rem;
        }

        .container {
          padding: 1rem 1rem 3rem;
        }

        .extension-card {
          padding: 2rem 1.5rem;
        }

        .extension-card h2 {
          font-size: 1.8rem;
        }

        .steps li {
          padding: 1rem 1.5rem 1rem 3.5rem;
          margin-bottom: 1rem;
        }

        .steps li::before {
          width: 2rem;
          height: 2rem;
          font-size: 0.9rem;
          left: -10px;
        }

        .download-btn {
          padding: 0.8rem 1.5rem;
          font-size: 1rem;
        }

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

        .feature-item {
          padding: 1rem;
        }

        .extension-placeholder {
          height: 250px;
        }

        .placeholder-icon {
          font-size: 3rem;
        }

        .usage-step {
          flex-direction: column;
          text-align: center;
          gap: 1rem;
        }

        .step-number {
          align-self: center;
        }

        .tips-section {
          padding: 1.5rem;
        }

        .final-cta {
          padding: 3rem 0;
        }

        .cta-content h2 {
          font-size: 2rem;
        }

        .cta-content p {
          font-size: 1rem;
        }

        .cta-buttons {
          flex-direction: column;
          align-items: center;
        }

        .cta-primary-btn,
        .cta-secondary-btn {
          width: 100%;
          max-width: 300px;
          justify-content: center;
        }
      }