/* roulang page: index */
:root {
            --color-primary: #1E293B;
            --color-accent: #0F766E;
            --color-highlight: #D97706;
            --color-bg-light: #F8FAFC;
            --color-bg-dark: #0F172A;
            --color-text-main: #334155;
            --color-text-muted: #64748B;
            --shadow-soft: 0 4px 20px -2px rgba(15, 23, 42, 0.05);
            --shadow-hover: 0 12px 30px -4px rgba(15, 23, 42, 0.08);
        }
        * { box-sizing: border-box; scroll-behavior: smooth; }
        body {
            font-family: system-ui, -apple-system, "PingFang SC", "Lantinghei SC", "Microsoft YaHei", sans-serif;
            color: var(--color-text-main);
            background-color: var(--color-bg-light);
            line-height: 1.75;
            overflow-x: hidden;
        }
        .container-custom {
            max-width: 1280px;
            margin-left: auto;
            margin-right: auto;
            padding-left: 1rem;
            padding-right: 1rem;
        }
        @media (min-width: 640px) { .container-custom { padding-left: 1.5rem; padding-right: 1.5rem; } }
        @media (min-width: 1024px) { .container-custom { padding-left: 2rem; padding-right: 2rem; } }
        .card-subtle {
            background: #FFFFFF;
            border: 1px solid rgba(226, 232, 240, 0.8);
            border-radius: 12px;
            box-shadow: var(--shadow-soft);
            transition: all 0.3s cubic-bezier(0.4, 0, 0.2, 1);
        }
        .card-subtle:hover {
            box-shadow: var(--shadow-hover);
            transform: translateY(-3px);
            border-color: rgba(15, 118, 110, 0.25);
        }
        .text-gradient {
            background: linear-gradient(135deg, #1E293B 0%, #0F766E 100%);
            -webkit-background-clip: text;
            -webkit-text-fill-color: transparent;
        }
        .btn-primary {
            background-color: var(--color-accent);
            color: #ffffff;
            transition: all 0.2s ease-in-out;
        }
        .btn-primary:hover {
            background-color: #0D645E;
            box-shadow: 0 8px 16px -4px rgba(15, 118, 110, 0.4);
        }
        .btn-amber {
            background-color: var(--color-highlight);
            color: #ffffff;
            transition: all 0.2s ease-in-out;
        }
        .btn-amber:hover {
            background-color: #B45309;
            box-shadow: 0 8px 16px -4px rgba(217, 119, 6, 0.35);
        }
        /* 手风琴过渡动画 */
        .faq-content {
            max-height: 0;
            overflow: hidden;
            transition: max-height 0.35s ease-out, opacity 0.3s ease-out;
            opacity: 0;
        }
        .faq-item.active .faq-content {
            max-height: 240px;
            opacity: 1;
        }
        .faq-item.active .faq-icon {
            transform: rotate(180deg);
        }