/* roulang page: index */
:root {
            --primary: #1E40AF;
            --primary-hover: #1D4ED8;
            --dark-space: #0F172A;
            --surface-bg: #F8FAFC;
            --border-light: rgba(226, 232, 240, 0.85);
            --card-shadow: 0 4px 20px -2px rgba(15, 23, 42, 0.05);
            --card-hover-shadow: 0 16px 32px -4px rgba(30, 64, 175, 0.12);
        }
        body {
            font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, "PingFang SC", "Hiragino Sans GB", "Microsoft YaHei", sans-serif;
            background-color: var(--surface-bg);
            color: #334155;
            overflow-x: hidden;
            scroll-behavior: smooth;
        }
        .text-hero-gradient {
            background: linear-gradient(135deg, #0F172A 0%, #1E40AF 100%);
            -webkit-background-clip: text;
            -webkit-text-fill-color: transparent;
        }
        .tactical-card {
            background: #FFFFFF;
            border: 1px solid var(--border-light);
            border-radius: 14px;
            box-shadow: var(--card-shadow);
            transition: all 0.28s cubic-bezier(0.4, 0, 0.2, 1);
        }
        .tactical-card:hover {
            transform: translateY(-4px);
            box-shadow: var(--card-hover-shadow);
            border-color: rgba(30, 64, 175, 0.25);
        }
        .dark-matrix-card {
            background: rgba(30, 41, 59, 0.65);
            border: 1px solid rgba(51, 65, 85, 0.8);
            border-radius: 12px;
            backdrop-filter: blur(8px);
        }
        .faq-accordion summary::-webkit-details-marker {
            display: none;
        }
        .faq-accordion[open] summary .accordion-chevron {
            transform: rotate(180deg);
        }
        .skew-offset-container {
            clip-path: polygon(0 0, 100% 0, 100% 92%, 0 100%);
        }