/* roulang page: index */
:root {
            --sidebar-width: 256px;
            --topbar-height: 60px;
            --transition-speed: 280ms;
            --color-primary: #1e3a5f;
            --color-accent: #3b82f6;
            --color-gold: #f0c040;
            --color-sidebar: #0f172a;
            --color-surface: #f8fafc;
        }

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

        html {
            scroll-behavior: smooth;
            -webkit-font-smoothing: antialiased;
            -moz-osx-font-smoothing: grayscale;
        }

        body {
            font-family: "Inter", "SF Pro Display", "PingFang SC", "Microsoft YaHei", "Helvetica Neue", Arial, sans-serif;
            line-height: 1.6;
            color: #1e293b;
            background-color: #f8fafc;
            min-height: 100vh;
            overflow-x: hidden;
        }

        img {
            max-width: 100%;
            height: auto;
            display: block;
        }

        a {
            text-decoration: none;
            color: inherit;
            transition: color 200ms ease;
        }

        button {
            cursor: pointer;
            border: none;
            background: none;
            font-family: inherit;
        }

        input,
        select,
        textarea {
            font-family: inherit;
        }

        /* 侧边栏 */
        .sidebar {
            position: fixed;
            top: 0;
            left: 0;
            width: var(--sidebar-width);
            height: 100vh;
            background-color: #0f172a;
            z-index: 1000;
            display: flex;
            flex-direction: column;
            box-shadow: 2px 0 12px rgba(0, 0, 0, 0.08);
            transition: transform var(--transition-speed) cubic-bezier(0.4, 0, 0.2, 1);
        }

        .sidebar-logo {
            padding: 24px 20px 20px;
            border-bottom: 1px solid rgba(255, 255, 255, 0.08);
            flex-shrink: 0;
        }

        .sidebar-logo .logo-text {
            font-size: 17px;
            font-weight: 700;
            color: #ffffff;
            letter-spacing: 0.02em;
            line-height: 1.35;
            display: block;
            transition: color 200ms ease;
        }

        .sidebar-logo .logo-text:hover {
            color: #f0c040;
        }

        .sidebar-logo .logo-sub {
            font-size: 11px;
            color: rgba(255, 255, 255, 0.45);
            letter-spacing: 0.04em;
            text-transform: uppercase;
            margin-top: 3px;
            display: block;
        }

        .sidebar-nav {
            flex: 1;
            padding: 16px 14px;
            overflow-y: auto;
            display: flex;
            flex-direction: column;
            gap: 4px;
        }

        .sidebar-nav .nav-item {
            display: flex;
            align-items: center;
            gap: 12px;
            padding: 12px 16px;
            border-radius: 10px;
            font-size: 15px;
            font-weight: 500;
            color: rgba(255, 255, 255, 0.7);
            transition: all 200ms ease;
            cursor: pointer;
            white-space: nowrap;
            position: relative;
        }

        .sidebar-nav .nav-item i {
            font-size: 18px;
            width: 22px;
            text-align: center;
            flex-shrink: 0;
        }

        .sidebar-nav .nav-item:hover {
            background-color: rgba(255, 255, 255, 0.06);
            color: #ffffff;
        }

        .sidebar-nav .nav-item.active {
            background-color: rgba(59, 130, 246, 0.2);
            color: #60a5fa;
            font-weight: 600;
        }

        .sidebar-nav .nav-item.active::before {
            content: '';
            position: absolute;
            left: -14px;
            top: 50%;
            transform: translateY(-50%);
            width: 3px;
            height: 24px;
            background-color: #3b82f6;
            border-radius: 0 3px 3px 0;
        }

        .sidebar-footer {
            padding: 16px 20px;
            border-top: 1px solid rgba(255, 255, 255, 0.08);
            flex-shrink: 0;
        }

        .sidebar-footer .footer-info {
            font-size: 12px;
            color: rgba(255, 255, 255, 0.35);
            line-height: 1.6;
        }

        /* 主内容区 */
        .main-content {
            margin-left: var(--sidebar-width);
            min-height: 100vh;
            display: flex;
            flex-direction: column;
            transition: margin-left var(--transition-speed) cubic-bezier(0.4, 0, 0.2, 1);
        }

        /* 移动端顶部栏 */
        .mobile-topbar {
            display: none;
            position: fixed;
            top: 0;
            left: 0;
            right: 0;
            height: var(--topbar-height);
            background-color: #ffffff;
            z-index: 999;
            box-shadow: 0 2px 12px rgba(0, 0, 0, 0.06);
            align-items: center;
            padding: 0 16px;
            gap: 12px;
        }

        .mobile-topbar .hamburger {
            width: 40px;
            height: 40px;
            display: flex;
            align-items: center;
            justify-content: center;
            border-radius: 10px;
            font-size: 20px;
            color: #1e293b;
            flex-shrink: 0;
            transition: background-color 200ms ease;
        }

        .mobile-topbar .hamburger:hover {
            background-color: #f1f5f9;
        }

        .mobile-topbar .topbar-logo {
            font-size: 15px;
            font-weight: 700;
            color: #1e3a5f;
            letter-spacing: 0.02em;
            line-height: 1.3;
            flex: 1;
        }

        /* 移动端遮罩 */
        .sidebar-overlay {
            display: none;
            position: fixed;
            inset: 0;
            background-color: rgba(0, 0, 0, 0.5);
            z-index: 998;
            opacity: 0;
            transition: opacity var(--transition-speed) ease;
        }

        .sidebar-overlay.visible {
            opacity: 1;
        }

        /* Hero装饰 */
        .hero-glow {
            position: absolute;
            border-radius: 50%;
            filter: blur(80px);
            opacity: 0.12;
            pointer-events: none;
        }

        /* 卡片hover */
        .card-hover-lift {
            transition: transform 280ms ease, box-shadow 280ms ease;
        }
        .card-hover-lift:hover {
            transform: translateY(-4px);
            box-shadow: 0 10px 25px -5px rgba(0, 0, 0, 0.10), 0 4px 10px -6px rgba(0, 0, 0, 0.06);
        }

        /* 步骤编号 */
        .step-number {
            width: 48px;
            height: 48px;
            border-radius: 50%;
            display: flex;
            align-items: center;
            justify-content: center;
            font-weight: 700;
            font-size: 18px;
            flex-shrink: 0;
        }

        /* 统计数字动画 */
        .stat-number {
            font-variant-numeric: tabular-nums;
            font-feature-settings: "tnum";
        }

        /* FAQ手风琴 */
        .faq-item {
            border-bottom: 1px solid #e2e8f0;
        }
        .faq-item:last-child {
            border-bottom: none;
        }
        .faq-question {
            cursor: pointer;
            transition: color 200ms ease;
        }
        .faq-question:hover {
            color: #3b82f6;
        }
        .faq-answer {
            max-height: 0;
            overflow: hidden;
            transition: max-height 350ms ease, padding 350ms ease;
        }
        .faq-item.open .faq-answer {
            max-height: 400px;
        }
        .faq-item.open .faq-icon {
            transform: rotate(180deg);
        }
        .faq-icon {
            transition: transform 300ms ease;
            flex-shrink: 0;
        }

        /* 页脚链接 */
        .footer-link {
            transition: color 200ms ease, opacity 200ms ease;
        }
        .footer-link:hover {
            color: #f0c040;
            opacity: 1;
        }

        /* 响应式 */
        @media (max-width: 1023px) {
            .sidebar {
                transform: translateX(-100%);
            }
            .sidebar.open {
                transform: translateX(0);
            }
            .sidebar-overlay {
                display: block;
                pointer-events: none;
            }
            .sidebar-overlay.visible {
                pointer-events: auto;
            }
            .mobile-topbar {
                display: flex;
            }
            .main-content {
                margin-left: 0;
                padding-top: var(--topbar-height);
            }
        }

        @media (min-width: 1024px) {
            .sidebar-overlay {
                display: none !important;
            }
            .mobile-topbar {
                display: none !important;
            }
            .sidebar {
                transform: translateX(0) !important;
            }
            .main-content {
                margin-left: var(--sidebar-width);
                padding-top: 0;
            }
        }

        @media (max-width: 768px) {
            .hero-title {
                font-size: 2rem !important;
                line-height: 1.25 !important;
            }
            .hero-subtitle {
                font-size: 1rem !important;
            }
            .section-title {
                font-size: 1.5rem !important;
            }
            .card-grid {
                grid-template-columns: 1fr !important;
            }
            .stat-row {
                flex-direction: column !important;
                gap: 20px !important;
            }
        }

        @media (max-width: 520px) {
            .sidebar {
                width: 100%;
                max-width: 300px;
            }
            .hero-title {
                font-size: 1.6rem !important;
            }
            .cta-button-group {
                flex-direction: column !important;
                width: 100%;
            }
            .cta-button-group a,
            .cta-button-group button {
                width: 100%;
                text-align: center;
                justify-content: center;
            }
        }

        /* 滚动条美化 */
        .sidebar-nav::-webkit-scrollbar {
            width: 4px;
        }
        .sidebar-nav::-webkit-scrollbar-track {
            background: transparent;
        }
        .sidebar-nav::-webkit-scrollbar-thumb {
            background: rgba(255, 255, 255, 0.15);
            border-radius: 4px;
        }

        /* 焦点可见 */
        a:focus-visible,
        button:focus-visible {
            outline: 2px solid #3b82f6;
            outline-offset: 2px;
            border-radius: 6px;
        }