/* roulang page: index */
:root {
            --primary: #1d4ed8;
            --primary-hover: #1e40af;
            --secondary: #0ea5e9;
            --bg-light: #f8fafc;
            --text-main: #0f172a;
            --text-muted: #475569;
            --border-soft: #e2e8f0;
            --card-radius: 1.25rem;
        }
        html {
            scroll-behavior: smooth;
        }
        body {
            font-family: system-ui, -apple-system, 'PingFang SC', 'Microsoft YaHei', sans-serif;
            color: var(--text-main);
            background-color: #ffffff;
            line-height: 1.7;
            overflow-x: hidden;
        }
        .coupon-mask {
            background-image: radial-gradient(circle at 0 50%, transparent 12px, #ffffff 13px), radial-gradient(circle at 100% 50%, transparent 12px, #ffffff 13px);
        }
        .coupon-border-dash {
            border-right: 2px dashed #cbd5e1;
        }
        .accordion-content {
            max-height: 0;
            transition: max-height 0.3s ease-out, opacity 0.25s ease-in-out;
            opacity: 0;
            overflow: hidden;
        }
        .accordion-content.open {
            max-height: 240px;
            opacity: 1;
        }