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

        body {
            font-family: -apple-system, BlinkMacSystemFont, "PingFang SC", "Helvetica Neue", sans-serif;
            background-color: #f7f8fa;
            color: #333;
            line-height: 1.6;
        }

        /* 导航栏 */
        .navbar {
            position: sticky;
            top: 0;
            background: rgba(255, 255, 255, 0.95);
            backdrop-filter: blur(10px);
            padding: 16px 40px;
            display: flex;
            justify-content: space-between;
            align-items: center;
            box-shadow: 0 2px 12px rgba(0, 0, 0, 0.04);
            z-index: 100;
        }

        .nav-brand {
            display: flex;
            align-items: center;
            gap: 10px;
        }

        .nav-logo {
            width: 40px;
            height: 40px;
            object-fit: contain;
        }

        .logo {
            font-size: 20px;
            font-weight: 600;
            color: #07c160;
        }

        .nav-links {
            display: flex;
            gap: 32px;
        }

        .nav-links a {
            text-decoration: none;
            color: #666;
            font-size: 15px;
            transition: color 0.3s;
        }

        .nav-links a:hover {
            color: #07c160;
        }

        /* v0.73.6: nav 右侧两 CTA 按钮容器 — 挨一起, 不变 nav 三栏布局 */
        .nav-actions {
            display: flex;
            gap: 10px;
            align-items: center;
        }

        .cta-btn-small {
            background: #07c160;
            color: white;
            padding: 8px 20px;
            border-radius: 20px;
            text-decoration: none;
            font-size: 14px;
            font-weight: 500;
            transition: background 0.3s;
            cursor: pointer;
        }

        .cta-btn-small:hover {
            background: #06ad56;
        }

        /* Hero 区域 */
        .hero {
            padding: 100px 40px 80px;
            text-align: center;
            background: linear-gradient(180deg, #e8faf0 0%, #f7f8fa 100%);
        }

        .hero h1 {
            font-size: 48px;
            font-weight: 700;
            margin-bottom: 20px;
            color: #1a1a1a;
        }

        .hero h1 span {
            color: #07c160;
        }

        .hero p {
            font-size: 18px;
            color: #666;
            margin-bottom: 40px;
            max-width: 600px;
            margin-left: auto;
            margin-right: auto;
        }

        .hero-btns {
            display: flex;
            gap: 16px;
            justify-content: center;
            margin-bottom: 60px;
        }

        .btn-primary {
            background: #07c160;
            color: white;
            padding: 14px 36px;
            border-radius: 28px;
            text-decoration: none;
            font-size: 16px;
            font-weight: 500;
            transition: all 0.3s;
            box-shadow: 0 4px 14px rgba(7, 193, 96, 0.3);
            cursor: pointer;
        }

        .btn-primary:hover {
            background: #06ad56;
            transform: translateY(-2px);
            box-shadow: 0 6px 20px rgba(7, 193, 96, 0.4);
        }

        .btn-secondary {
            background: white;
            color: #333;
            padding: 14px 36px;
            border-radius: 28px;
            text-decoration: none;
            font-size: 16px;
            font-weight: 500;
            border: 1px solid #e5e5e5;
            transition: all 0.3s;
        }

        .btn-secondary:hover {
            border-color: #07c160;
            color: #07c160;
        }

        /* 手机预览图 */
        .phone-mockup {
            max-width: 320px;
            margin: 0 auto;
            background: white;
            border-radius: 32px;
            padding: 12px;
            box-shadow: 0 20px 60px rgba(0, 0, 0, 0.1);
        }

        .phone-screen {
            background: #f7f8fa;
            border-radius: 24px;
            padding: 24px 16px;
            min-height: 500px;
        }

        .phone-status-bar {
            display: flex;
            justify-content: space-between;
            font-size: 12px;
            color: #333;
            margin-bottom: 20px;
        }

        .phone-title {
            text-align: center;
            font-size: 18px;
            font-weight: 600;
            margin-bottom: 24px;
        }

        .stats-row {
            display: flex;
            justify-content: space-around;
            background: white;
            border-radius: 12px;
            padding: 16px;
            margin-bottom: 20px;
        }

        .stat-item {
            text-align: center;
        }

        .stat-num {
            font-size: 24px;
            font-weight: 600;
            color: #333;
        }

        .stat-label {
            font-size: 12px;
            color: #999;
            margin-top: 4px;
        }

        .feature-cards-row {
            display: grid;
            grid-template-columns: 1fr 1fr;
            gap: 12px;
            margin-bottom: 20px;
        }

        .mini-card {
            background: white;
            border-radius: 12px;
            padding: 20px 12px;
            text-align: center;
        }

        .mini-icon {
            width: 48px;
            height: 48px;
            margin: 0 auto 10px;
            background: #e8faf0;
            border-radius: 12px;
            display: flex;
            align-items: center;
            justify-content: center;
            color: #07c160;
            font-size: 20px;
        }

        .mini-card h4 {
            font-size: 14px;
            margin-bottom: 4px;
        }

        .mini-card p {
            font-size: 11px;
            color: #999;
        }

        /* 通用区块 */
        .section {
            padding: 80px 40px;
            max-width: 1200px;
            margin: 0 auto;
        }

        .section-title {
            text-align: center;
            margin-bottom: 60px;
        }

        .section-title h2 {
            font-size: 32px;
            margin-bottom: 12px;
        }

        .section-title p {
            color: #666;
            font-size: 16px;
        }

        /* 核心玩法卡片网格 */
        .features-grid {
            display: grid;
            grid-template-columns: repeat(3, 1fr);
            gap: 24px;
        }

        .feature-card {
            background: white;
            border-radius: 16px;
            padding: 32px 24px;
            transition: all 0.3s;
            border: 1px solid #f0f0f0;
        }

        .feature-card:hover {
            transform: translateY(-4px);
            box-shadow: 0 12px 32px rgba(0, 0, 0, 0.08);
            border-color: #07c160;
        }

        .feature-icon {
            width: 56px;
            height: 56px;
            background: #e8faf0;
            border-radius: 14px;
            display: flex;
            align-items: center;
            justify-content: center;
            font-size: 24px;
            color: #07c160;
            margin-bottom: 20px;
        }

        .feature-card h3 {
            font-size: 20px;
            margin-bottom: 12px;
        }

        .feature-card p {
            color: #666;
            font-size: 14px;
            line-height: 1.7;
        }

        /* 词库区域 */
        .wordbooks {
            background: white;
            border-radius: 20px;
            padding: 40px;
        }

        .wordbook-grid {
            display: grid;
            grid-template-columns: repeat(4, 1fr);
            gap: 16px;
        }

        .wordbook-item {
            background: #f7f8fa;
            border-radius: 12px;
            padding: 20px;
            transition: all 0.3s;
            cursor: pointer;
        }

        .wordbook-item:hover {
            background: #e8faf0;
        }

        .wordbook-item h4 {
            font-size: 16px;
            margin-bottom: 6px;
        }

        .wordbook-item .count {
            color: #07c160;
            font-size: 14px;
            font-weight: 500;
        }

        .wordbook-item .desc {
            color: #999;
            font-size: 12px;
            margin-top: 6px;
        }

        /* 选择难度 - 悬浮卡片效果 */
        .modes {
            display: grid;
            grid-template-columns: repeat(4, 1fr);
            gap: 24px;
            margin-top: 40px;
        }

        .mode-card {
            background: white;
            border-radius: 16px;
            padding: 32px 24px;
            text-align: center;
            border: 1px solid #f0f0f0;
            transition: all 0.3s;
            cursor: pointer;
        }

        .mode-card:hover {
            transform: translateY(-6px);
            box-shadow: 0 12px 32px rgba(0, 0, 0, 0.08);
            border-color: #07c160;
        }

        .mode-card.active {
            border-color: #07c160;
            background: #f0fdf5;
        }

        .mode-card h4 {
            font-size: 18px;
            margin-bottom: 8px;
        }

        .mode-card p {
            font-size: 14px;
            color: #666;
            line-height: 1.6;
        }

        /* 底部 CTA */
        .cta-section {
            background: linear-gradient(135deg, #07c160 0%, #10b981 100%);
            color: white;
            padding: 80px 40px;
            text-align: center;
            margin-top: 40px;
        }

        .cta-section h2 {
            font-size: 32px;
            margin-bottom: 16px;
        }

        .cta-section p {
            font-size: 16px;
            opacity: 0.9;
            margin-bottom: 32px;
        }

        .btn-white {
            background: white;
            color: #07c160;
            padding: 14px 40px;
            border-radius: 28px;
            text-decoration: none;
            font-size: 16px;
            font-weight: 600;
            display: inline-block;
            transition: all 0.3s;
            cursor: pointer;
        }

        .btn-white:hover {
            transform: translateY(-2px);
            box-shadow: 0 8px 24px rgba(0, 0, 0, 0.15);
        }

        /* v0.73.5: '登录' 按钮 (nav 小 + 底部 CTA 大) — 跟立即体验并排 */
        .cta-btn-outline {
            display: inline-block;
            background: transparent;
            color: #07c160;
            border: 1.5px solid #07c160;
            padding: 8px 20px;
            border-radius: 20px;
            text-decoration: none;
            font-size: 14px;
            font-weight: 500;
            transition: background 0.3s, color 0.3s;
            cursor: pointer;
        }
        .cta-btn-outline:hover {
            background: #07c160;
            color: #fff;
        }

/* 小程序码弹窗 */
        .modal-overlay {
            position: fixed;
            inset: 0;
            background: rgba(0, 0, 0, 0.5);
            display: flex;
            align-items: center;
            justify-content: center;
            z-index: 1000;
            opacity: 0;
            visibility: hidden;
            transition: all 0.3s ease;
        }

        .modal-overlay.show {
            opacity: 1;
            visibility: visible;
        }

        .modal-content {
            background: white;
            width: 90%;
            max-width: 420px;
            border-radius: 24px;
            padding: 32px 24px;
            position: relative;
            transform: translateY(20px);
            transition: transform 0.3s ease;
        }

        .modal-overlay.show .modal-content {
            transform: translateY(0);
        }

        .modal-close {
            position: absolute;
            top: 16px;
            right: 16px;
            width: 32px;
            height: 32px;
            border-radius: 50%;
            background: #f7f8fa;
            color: #666;
            display: flex;
            align-items: center;
            justify-content: center;
            font-size: 18px;
            cursor: pointer;
            transition: all 0.3s;
        }

        .modal-close:hover {
            background: #07c160;
            color: white;
        }

        .modal-title {
            text-align: center;
            font-size: 20px;
            font-weight: 600;
            margin-bottom: 8px;
            color: #1a1a1a;
        }

        .modal-desc {
            text-align: center;
            color: #666;
            font-size: 14px;
            margin-bottom: 24px;
        }

        .qrcode-box {
            display: flex;
            justify-content: center;
            padding: 16px;
            background: #f7f8fa;
            border-radius: 16px;
        }

        .qrcode-box img {
            width: 280px;
            height: 280px;
            object-fit: contain;
            border-radius: 12px;
        }

        .modal-tip {
            text-align: center;
            margin-top: 16px;
            font-size: 13px;
            color: #999;
        }

        /* 页脚 */
        .footer {
            background: #1a1a1a;
            color: #999;
            padding: 40px 20px;
            text-align: center;
            font-size: 14px;
        }

        .footer a {
            color: #999;
            text-decoration: none;
        }

        .footer a:hover {
            color: #07c160;
        }

        .footer-brand {
            margin-bottom: 12px;
            font-size: 16px;
            font-weight: 600;
            color: #fff;
        }

        .footer-icp {
            margin-top: 12px;
            font-size: 13px;
        }

        /* 响应式 */
        @media (max-width: 768px) {
            .navbar {
                padding: 12px 20px;
            }
            .nav-links {
                display: none;
            }
            .hero {
                padding: 60px 20px 40px;
            }
            .hero h1 {
                font-size: 32px;
            }
            .features-grid {
                grid-template-columns: 1fr;
            }
            .wordbook-grid {
                grid-template-columns: repeat(2, 1fr);
            }
            .modes {
                grid-template-columns: repeat(2, 1fr);
                gap: 16px;
            }
            .section {
                padding: 60px 20px;
            }
        }