/* roulang page: index */
:root {
            --primary: #0F172A;
            --signal-green: #00D285;
            --bus-blue: #3B82F6;
            --surface-dark: #0B0F19;
            --bg-light: #F8FAFC;
            --text-main: #1E293B;
            --text-muted: #64748B;
            --border-soft: #E2E8F0;
            --radius-box: 16px;
            --shadow-subtle: 0 4px 20px -2px rgba(15, 23, 42, 0.05);
            --shadow-card: 0 10px 30px -4px rgba(15, 23, 42, 0.08);
            --shadow-accent: 0 0 25px -3px rgba(0, 210, 133, 0.35);
        }

        body {
            background-color: var(--bg-light);
            color: var(--text-main);
            font-family: 'Inter', -apple-system, BlinkMacSystemFont, "PingFang SC", "Segoe UI", sans-serif;
            overflow-x: hidden;
        }

        .tool-card {
            background: #FFFFFF;
            border: 1px solid var(--border-soft);
            border-radius: var(--radius-box);
            transition: all 0.3s cubic-bezier(0.16, 1, 0.3, 1);
        }

        .tool-card:hover {
            transform: translateY(-4px);
            border-color: var(--signal-green);
            box-shadow: var(--shadow-card), 0 0 16px -2px rgba(0, 210, 133, 0.15);
        }

        .hud-border {
            border: 1px solid rgba(0, 210, 133, 0.25);
            background: rgba(11, 15, 25, 0.85);
            backdrop-filter: blur(12px);
        }

        .custom-scrollbar::-webkit-scrollbar {
            height: 6px;
            width: 6px;
        }
        .custom-scrollbar::-webkit-scrollbar-thumb {
            background: #CBD5E1;
            border-radius: 999px;
        }