:root {
    --primary: #2563eb;
    --secondary: #7c3aed;
    --gradient: linear-gradient(135deg, var(--primary), var(--secondary));
    --bg-color: #f4f7fb;
    --transition: all 0.3s cubic-bezier(0.4, 0, 0.2, 1);
}

/* 窄边渐变滚动条 */
::-webkit-scrollbar {
    width: 7px;
    height: 7px;
}

::-webkit-scrollbar-track {
    background: transparent;
}

::-webkit-scrollbar-thumb {
    background: var(--gradient);
    border-radius: 10px;
    border: 2px solid var(--bg-color);
    transition: var(--transition);
}

::-webkit-scrollbar-thumb:hover {
    background: linear-gradient(135deg, #1d4ed8, #6d28d9);
}

/* Firefox */
html {
    scrollbar-width: thin;
    scrollbar-color: var(--primary) transparent;
}