/* 首屏极少数关键样式，避免进度条初始闪烁 */
#progress-bar {
    transform: scaleX(0);
}

/* 跳过导航：默认离屏，聚焦时进入视口（勿用 display:none，否则无法聚焦） */
.skip-to-main {
    position: fixed;
    top: 0;
    left: 50%;
    z-index: 100000;
    padding: 0.65rem 1.15rem;
    font-size: 0.875rem;
    font-weight: 600;
    line-height: 1.25;
    color: #fff;
    text-decoration: none;
    background: #163268;
    border-radius: 0;
    box-shadow: 0 8px 24px rgba(22, 50, 104, 0.35);
    transform: translate(-50%, -120%);
    transition: transform 0.2s ease;
}

.skip-to-main:focus {
    transform: translate(-50%, 0.5rem);
    outline: 2px solid #fff;
    outline-offset: 2px;
}

.skip-to-main:focus:not(:focus-visible) {
    transform: translate(-50%, -120%);
    outline: none;
}

.skip-to-main:focus-visible {
    transform: translate(-50%, 0.5rem);
    outline: 2px solid #fff;
    outline-offset: 2px;
}

#main-content:focus {
    outline: none;
}

@media (prefers-reduced-motion: reduce) {
    .skip-to-main {
        transition: none;
    }
}