:root {
            --primary: #ec608f;
            --primary-hover: #d84b7a;
            --primary-light: rgba(236, 96, 143, 0.08);
            --primary-border: rgba(236, 96, 143, 0.2);
            --bg-main: #fcf9fa;
            --bg-card: #ffffff;
            --text-main: #1e2025;
            --text-muted: #5c6270;
            --text-light: #8a92a3;
            --border-color: #eaeef5;
            --radius-sm: 6px;
            --radius-md: 10px;
            --radius-lg: 12px;
            --shadow-sm: 0 2px 8px rgba(0, 0, 0, 0.04);
            --shadow-md: 0 6px 20px rgba(0, 0, 0, 0.06);
            --max-width: 1180px;
        }

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

        body {
            font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, "Helvetica Neue", Arial, sans-serif;
            background-color: var(--bg-main);
            color: var(--text-main);
            line-height: 1.65;
            word-break: keep-all;
            overflow-wrap: break-word;
            -webkit-font-smoothing: antialiased;
        }

        a {
            color: var(--primary);
            text-decoration: none;
            transition: color 0.15s ease;
        }

        a:hover {
            color: var(--primary-hover);
        }

        .envelope {
            width: 100%;
            min-height: 100vh;
            display: flex;
            flex-direction: column;
        }

        /* 顶部导航 */
        .vista {
            background-color: #ffffff;
            border-bottom: 1px solid var(--border-color);
            position: sticky;
            top: 0;
            z-index: 100;
            box-shadow: var(--shadow-sm);
        }

        .vector {
            max-width: var(--max-width);
            margin: 0 auto;
            padding: 0 24px;
            height: 72px;
            display: flex;
            flex-wrap: wrap;
            align-items: center;
            justify-content: space-between;
        }

        .nose {
            display: flex;
            align-items: center;
            min-width: 0;
        }

        .nose img {
            height: 40px;
            width: auto;
            display: block;
        }

        .draft {
            display: flex;
            flex-wrap: wrap;
            align-items: center;
            gap: 28px;
            list-style: none;
        }

        .rudder {
            font-size: 15px;
            font-weight: 500;
            color: var(--text-muted);
            padding: 8px 12px;
            border-radius: var(--radius-sm);
            transition: all 0.15s ease;
        }

        .rudder:hover {
            color: var(--primary);
            background-color: var(--primary-light);
        }

        .rudder.active,
        .rudder.active {
            color: var(--primary);
            font-weight: 600;
            background-color: var(--primary-light);
        }

        /* 主体布局 */
        main {
            flex: 1;
            max-width: var(--max-width);
            width: 100%;
            margin: 0 auto;
            padding: 40px 24px;
            display: flex;
            flex-direction: column;
            gap: 56px;
        }

        /* Hero 下载首屏 (acquire) */
        .launch {
            background: linear-gradient(135deg, #ffffff 0%, #fff7f9 100%);
            border: 1px solid var(--primary-border);
            border-radius: var(--radius-lg);
            padding: 48px;
            box-shadow: var(--shadow-md);
            display: flex;
            flex-wrap: wrap;
            gap: 40px;
            align-items: center;
        }

        .zenith {
            flex: 1 1 500px;
            min-width: 0;
        }

        .feather {
            display: inline-flex;
            align-items: center;
            gap: 8px;
            padding: 6px 14px;
            background-color: var(--primary-light);
            border: 1px solid var(--primary-border);
            border-radius: 20px;
            color: var(--primary);
            font-size: 13px;
            font-weight: 600;
            margin-bottom: 20px;
        }

        .fin {
            font-size: 34px;
            line-height: 1.3;
            font-weight: 800;
            color: var(--text-main);
            margin-bottom: 16px;
            white-space: normal;
            word-break: break-word;
        }

        .apex {
            font-size: 16px;
            color: var(--text-muted);
            margin-bottom: 32px;
            line-height: 1.7;
            word-break: break-word;
        }

        .emblem {
            display: flex;
            flex-wrap: wrap;
            gap: 16px;
        }

        .thrust {
            display: inline-flex;
            align-items: center;
            justify-content: center;
            gap: 10px;
            background-color: var(--primary);
            color: #ffffff;
            padding: 14px 28px;
            border-radius: var(--radius-md);
            font-weight: 600;
            font-size: 15px;
            transition: all 0.15s ease;
            box-shadow: 0 4px 14px rgba(236, 96, 143, 0.3);
            border: none;
            cursor: pointer;
            min-width: 0;
        }

        .thrust:hover {
            background-color: var(--primary-hover);
            color: #ffffff;
            transform: translateY(-2px);
            box-shadow: 0 6px 20px rgba(236, 96, 143, 0.4);
        }

        .propel {
            display: inline-flex;
            align-items: center;
            justify-content: center;
            gap: 10px;
            background-color: #ffffff;
            color: var(--text-main);
            border: 1px solid var(--border-color);
            padding: 14px 24px;
            border-radius: var(--radius-md);
            font-weight: 600;
            font-size: 15px;
            transition: all 0.15s ease;
            cursor: pointer;
            min-width: 0;
        }

        .propel:hover {
            border-color: var(--primary);
            color: var(--primary);
            background-color: var(--primary-light);
            transform: translateY(-2px);
        }

        .fleet-wrap {
            flex: 1 1 400px;
            min-width: 0;
            text-align: center;
        }

        .fleet {
            max-width: 100%;
            height: auto;
            border-radius: var(--radius-md);
            box-shadow: var(--shadow-md);
            border: 1px solid var(--border-color);
            display: block;
        }

        /* 快捷客户端卡片展示 */
        .origami-grid {
            display: flex;
            flex-wrap: wrap;
            gap: 20px;
            margin-top: 36px;
            width: 100%;
        }

        .origami {
            flex: 1 1 240px;
            min-width: 0;
            background-color: #ffffff;
            border: 1px solid var(--border-color);
            border-radius: var(--radius-md);
            padding: 24px;
            transition: all 0.15s ease;
            display: flex;
            flex-direction: column;
            justify-content: space-between;
        }

        .origami:hover {
            border-color: var(--primary-border);
            box-shadow: var(--shadow-md);
            transform: translateY(-3px);
        }

        .crease {
            width: 44px;
            height: 44px;
            border-radius: var(--radius-sm);
            background-color: var(--primary-light);
            display: flex;
            align-items: center;
            justify-content: center;
            margin-bottom: 16px;
            color: var(--primary);
            flex-shrink: 0;
        }

        .origami .fin {
            font-size: 18px;
            font-weight: 700;
            margin-bottom: 8px;
        }

        .origami .apex {
            font-size: 14px;
            color: var(--text-muted);
            margin-bottom: 20px;
            flex-grow: 1;
        }

        /* 平台参数矩阵 Section (comparison) */
        .airspace {
            background-color: #ffffff;
            border: 1px solid var(--border-color);
            border-radius: var(--radius-lg);
            padding: 40px;
            box-shadow: var(--shadow-sm);
        }

        .airspace .fin {
            font-size: 26px;
            text-align: center;
            margin-bottom: 12px;
        }

        .airspace .apex {
            text-align: center;
            max-width: 720px;
            margin: 0 auto 36px auto;
        }

        .glider-table {
            width: 100%;
            border-collapse: collapse;
            margin-top: 16px;
        }

        .glider-table th,
        .glider-table td {
            padding: 16px 20px;
            text-align: left;
            border-bottom: 1px solid var(--border-color);
            font-size: 14px;
            word-break: break-word;
        }

        .glider-table th {
            background-color: var(--bg-main);
            color: var(--text-main);
            font-weight: 700;
        }

        .glider-table tr:hover td {
            background-color: #fff9fb;
        }

        .plume-code {
            font-family: SFMono-Regular, Consolas, "Liberation Mono", Menlo, monospace;
            font-size: 12px;
            background-color: #f1f3f7;
            padding: 4px 8px;
            border-radius: 4px;
            color: #4a5160;
            display: inline-block;
            max-width: 280px;
            overflow: hidden;
            text-overflow: ellipsis;
            white-space: nowrap;
        }

        /* 安装步骤 Aside (steps) */
        .skybox {
            background-color: #ffffff;
            border: 1px solid var(--border-color);
            border-radius: var(--radius-lg);
            padding: 40px;
            box-shadow: var(--shadow-sm);
        }

        .skybox .fin {
            font-size: 26px;
            margin-bottom: 12px;
        }

        .skybox .apex {
            margin-bottom: 32px;
        }

        .biplane-steps {
            display: flex;
            flex-wrap: wrap;
            gap: 24px;
        }

        .biplane {
            flex: 1 1 280px;
            min-width: 0;
            background-color: var(--bg-main);
            border: 1px solid var(--border-color);
            border-radius: var(--radius-md);
            padding: 28px;
            position: relative;
        }

        .biplane-num {
            font-size: 36px;
            font-weight: 900;
            color: var(--primary);
            opacity: 0.3;
            line-height: 1;
            margin-bottom: 12px;
        }

        .biplane .fin {
            font-size: 18px;
            margin-bottom: 10px;
        }

        .biplane .apex {
            font-size: 14px;
            margin-bottom: 0;
        }

        /* FAQ 与更新日志 Aside (faq / system_requirements) */
        .updraft {
            background-color: #ffffff;
            border: 1px solid var(--border-color);
            border-radius: var(--radius-lg);
            padding: 40px;
            box-shadow: var(--shadow-sm);
            display: flex;
            flex-wrap: wrap;
            gap: 40px;
        }

        .updraft-left {
            flex: 1 1 450px;
            min-width: 0;
        }

        .updraft-right {
            flex: 1 1 450px;
            min-width: 0;
        }

        .updraft .fin {
            font-size: 24px;
            margin-bottom: 16px;
        }

        .trail-draft {
            list-style: none;
            display: flex;
            flex-direction: column;
            gap: 16px;
        }

        .trail-trail {
            border: 1px solid var(--border-color);
            border-radius: var(--radius-md);
            padding: 20px;
            background-color: #ffffff;
            transition: border-color 0.15s ease;
        }

        .trail-trail:hover {
            border-color: var(--primary-border);
        }

        .trail-trail-fin {
            font-size: 16px;
            font-weight: 700;
            color: var(--text-main);
            margin-bottom: 8px;
            display: flex;
            align-items: center;
            gap: 8px;
        }

        .trail-trail-desc {
            font-size: 14px;
            color: var(--text-muted);
            line-height: 1.6;
        }

        .log-origami {
            background-color: var(--bg-main);
            border-radius: var(--radius-md);
            padding: 24px;
            border: 1px solid var(--border-color);
        }

        .log-vista {
            display: flex;
            flex-wrap: wrap;
            justify-content: space-between;
            align-items: center;
            margin-bottom: 16px;
            border-bottom: 1px solid var(--border-color);
            padding-bottom: 12px;
        }

        .log-tag {
            background-color: var(--primary);
            color: #ffffff;
            font-size: 12px;
            padding: 4px 10px;
            border-radius: 12px;
            font-weight: 600;
        }

        .log-date {
            font-size: 13px;
            color: var(--text-light);
        }

        .log-body {
            font-size: 14px;
            color: var(--text-muted);
            line-height: 1.7;
        }

        .log-body ul {
            padding-left: 20px;
            margin-top: 8px;
        }

        .log-body li {
            margin-bottom: 6px;
        }

        /* 页脚区域 */
        .hangar {
            background-color: #ffffff;
            border-top: 1px solid var(--border-color);
            padding: 48px 24px 32px 24px;
            margin-top: 40px;
        }

        .tarmac {
            max-width: var(--max-width);
            margin: 0 auto;
            display: flex;
            flex-wrap: wrap;
            gap: 40px;
            justify-content: space-between;
            margin-bottom: 36px;
        }

        .stamp {
            flex: 1 1 300px;
            min-width: 0;
        }

        .stamp-name {
            font-size: 20px;
            font-weight: 800;
            color: var(--text-main);
            margin-bottom: 12px;
        }

        .stamp-desc {
            font-size: 14px;
            color: var(--text-muted);
            line-height: 1.6;
        }

        .tarmac-links {
            display: flex;
            flex-wrap: wrap;
            gap: 48px;
        }

        .tarmac-col {
            display: flex;
            flex-direction: column;
            gap: 12px;
        }

        .tarmac-col-fin {
            font-size: 15px;
            font-weight: 700;
            color: var(--text-main);
            margin-bottom: 4px;
        }

        .landing {
            max-width: var(--max-width);
            margin: 0 auto;
            padding-top: 24px;
            border-top: 1px solid var(--border-color);
            display: flex;
            flex-wrap: wrap;
            justify-content: space-between;
            align-items: center;
            gap: 16px;
            font-size: 13px;
            color: var(--text-light);
        }

        /* 响应式调整 */
        @media (max-width: 768px) {
            .vector {
                height: auto;
                padding: 16px;
                flex-direction: column;
                gap: 16px;
                align-items: flex-start;
            }

            .draft {
                width: 100%;
                gap: 12px;
                justify-content: flex-start;
            }

            .launch {
                padding: 24px;
            }

            .fin {
                font-size: 26px;
            }

            .airspace, .skybox, .updraft {
                padding: 24px;
            }

            .glider-table th, .glider-table td {
                padding: 12px 10px;
                font-size: 13px;
            }

            .plume-code {
                max-width: 140px;
            }
        }