/* ============================================
   组件：渐变背景容器（性能优化版）
   依赖：themes/*.css
   说明：独立的渐变背景，覆盖顶部栏和搜索区域
   ============================================ */

.gradient-bg {
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    height: 500px;
    background: linear-gradient(180deg,
        rgba(var(--bs-primary-rgb, 13,110,253), .25) 0%,
        rgba(var(--bs-primary-rgb, 13,110,253), .15) 30%,
        rgba(var(--bs-primary-rgb, 13,110,253), .08) 60%,
        transparent 100%);
    z-index: 0;
    pointer-events: none;
}

/* 响应式调整 */
@media (min-width: 768px) {
    .gradient-bg {
        height: 600px;
    }
}

@media (min-width: 992px) {
    .gradient-bg {
        height: 700px;
    }
}