/* roulang page: index */
:root {
            --bg-base: #0E1013;
            --bg-panel: #16191E;
            --bg-card: #1E232B;
            --border-line: #2A303C;
            --accent-orange: #FF5E1E;
            --accent-orange-hover: #FF7738;
            --radar-green: #00E599;
            --text-light: #F1F3F5;
            --text-muted: #8C96A5;
        }

        body {
            background-color: var(--bg-base);
            color: var(--text-light);
            font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, "PingFang SC", "Microsoft YaHei", sans-serif;
            overflow-x: hidden;
            letter-spacing: -0.01em;
        }

        /* 战术切角与准星 HUD 细节 */
        .hud-corner {
            clip-path: polygon(0 0, calc(100% - 14px) 0, 100% 14px, 100% 100%, 14px 100%, 0 calc(100% - 14px));
        }

        .hud-border {
            position: relative;
        }
        .hud-border::before {
            content: '';
            position: absolute;
            top: -1px;
            left: -1px;
            width: 8px;
            height: 8px;
            border-top: 2px solid var(--accent-orange);
            border-left: 2px solid var(--accent-orange);
        }
        .hud-border::after {
            content: '';
            position: absolute;
            bottom: -1px;
            right: -1px;
            width: 8px;
            height: 8px;
            border-bottom: 2px solid var(--accent-orange);
            border-right: 2px solid var(--accent-orange);
        }

        /* 雷达脉冲动画 */
        @keyframes radar-pulse {
            0% { transform: scale(0.95); opacity: 0.8; box-shadow: 0 0 0 0 rgba(0, 229, 153, 0.7); }
            70% { transform: scale(1); opacity: 1; box-shadow: 0 0 0 6px rgba(0, 229, 153, 0); }
            100% { transform: scale(0.95); opacity: 0.8; box-shadow: 0 0 0 0 rgba(0, 229, 153, 0); }
        }
        .radar-beacon {
            animation: radar-pulse 2s infinite ease-in-out;
        }

        /* 平滑手风琴过渡 */
        .faq-content {
            max-height: 0;
            overflow: hidden;
            transition: max-height 0.35s cubic-bezier(0.16, 1, 0.3, 1), padding 0.35s ease;
        }
        .faq-item.active .faq-content {
            max-height: 240px;
            padding-top: 1rem;
        }
        .faq-item.active .faq-icon {
            transform: rotate(45deg);
            color: var(--accent-orange);
        }
        .faq-item.active {
            border-color: var(--accent-orange);
            background-color: #1a1e26;
        }

        /* 自定义滚动条 */
        ::-webkit-scrollbar {
            width: 6px;
        }
        ::-webkit-scrollbar-track {
            background: #0E1013;
        }
        ::-webkit-scrollbar-thumb {
            background: #2A303C;
            border-radius: 3px;
        }
        ::-webkit-scrollbar-thumb:hover {
            background: #FF5E1E;
        }