/* =========================================================
   itnine 顶部导航：豆包样式全宽二级下拉菜单
   - 一级导航：悬停放大 scale(1.18) + 变色 + 下划线左向右展开 + 箭头旋转
   - 二级面板：相对吸顶导航栏横贯全宽、纯白底、顶部1px分割线 + 柔和阴影
   - 强调色：沿用站点按钮渐变主色 #355fd3 蓝紫系
   ========================================================= */

:root {
    --nav-accent: #355fd3;
    --nav-accent-soft: rgba(53, 95, 211, 0.07);
}

/* ---------- 一级导航链接：还原为可 scale 的文字，去掉旧胶囊背景 ---------- */
.site-header .nav .nav-link,
.site-header .desktop-nav .nav-link {
    position: relative;
    display: inline-flex;
    align-items: center;
    gap: 6px;
    border-radius: 0 !important;
    background: transparent !important;
    transform-origin: 50% 100%;
    transition:
            transform 0.28s cubic-bezier(0.22, 0.61, 0.36, 1),
            color 0.28s ease !important;
    will-change: transform;
}

.site-header .nav .nav-link:hover,
.site-header .desktop-nav .nav-link:hover {
    transform: scale(1.18);
    background: transparent !important;
    color: var(--nav-accent);
}

/* ---------- 悬停下划线：从左向右展开 ---------- */
.site-header .nav .nav-link::after,
.site-header .desktop-nav .nav-link::after {
    content: "";
    position: absolute;
    left: 14px;
    right: 14px;
    bottom: 2px;
    height: 2px;
    border-radius: 2px;
    background: var(--nav-accent);
    transform: scaleX(0);
    transform-origin: left;
    transition: transform 0.28s ease;
}

.site-header .nav-item:hover .nav-link::after,
.site-header .nav-item.open .nav-link::after,
.site-header .nav-item.active .nav-link::after {
    transform: scaleX(1);
}

/* ---------- 箭头：悬停 / 展开时旋转 180° ---------- */
.nav-link .caret {
    width: 11px;
    height: 11px;
    flex: none;
    animation: none;   /* 消除首页 hero 打字机光标 .caret 的 blink 闪烁动画误伤导航箭头 */
    background: transparent !important;   /* 消除首页 hero 全局 .caret 的橙/金黄背景色块误伤导航箭头，全站统一无底色 */
    box-shadow: none !important;
    transition: transform 0.25s ease;
}

.nav-item:hover .nav-link .caret,
.nav-item.open .nav-link .caret {
    transform: rotate(180deg);
}

/* ---------- 当前页 active：去掉旧胶囊背景，强调色 + 常显下划线 ---------- */
.site-header .nav .nav-link.active,
.site-header .desktop-nav .nav-link.active {
    color: var(--nav-accent) !important;
    background: transparent !important;
}

/* =========================================================
   二级下拉：全宽面板
   相对吸顶导航栏（sticky 作为定位上下文）定位，横贯整行；
   无圆角、纯白底、顶部 1px 分割线 + 下方柔和阴影。
   ========================================================= */
.site-header .nav .dropdown,
.site-header .desktop-nav .dropdown {
    position: absolute;
    top: 100%;
    left: 0;
    right: 0;
    z-index: 60;
    background: #fff;
    border-top: 1px solid #e4eaf3;
    box-shadow: 0 24px 48px rgba(25, 40, 70, 0.12);
    opacity: 0;
    visibility: hidden;
    transform: translateY(12px);
    transition:
            opacity 0.22s ease,
            transform 0.22s ease,
            visibility 0.22s;
    pointer-events: none;
}

.site-header .nav-item.open .dropdown {
    opacity: 1;
    visibility: visible;
    transform: translateY(0);
    pointer-events: auto;
}

/* 面板内容与正文同宽居中（对齐站点 .container ~1280px） */
.site-header .dropdown .dropdown-inner {
    width: min(1280px, 94%);
    margin-inline: auto;
    padding-block: 26px;
}

/* 子链接多列网格 */
.site-header .dropdown .dropdown-grid {
    display: grid;
    grid-template-columns: repeat(3, minmax(0, 1fr));
    gap: 6px 40px;
}

.site-header .dropdown .dropdown-grid a {
    display: block;
    padding: 10px 12px;
    font-size: 15px;
    font-weight: 600;
    color: #34425e;
    border-radius: 8px;
    transition:
            color 0.2s ease,
            padding-left 0.2s ease,
            background 0.2s ease;
}

.site-header .dropdown .dropdown-grid a:hover {
    color: var(--nav-accent);
    background: var(--nav-accent-soft);
    padding-left: 18px;
}

.site-header .dropdown .dropdown-grid a:focus-visible {
    outline: 2px solid var(--nav-accent);
    outline-offset: 2px;
}

/* =========================================================
   响应式：窄屏（<860px）隐藏二级面板，保留汉堡菜单
   ========================================================= */
@media (max-width: 860px) {
    .site-header .nav .nav-link,
    .site-header .desktop-nav .nav-link {
        transform: none !important;
    }
    .site-header .nav .nav-link::after,
    .site-header .desktop-nav .nav-link::after {
        display: none;
    }
    .site-header .nav .dropdown,
    .site-header .desktop-nav .dropdown {
        display: none;
    }
}