/* ============ 导航页美化样式（作用域 .nav-root，隔离 Chic 主题） ============ */

.nav-root {
    --card-bg: #ffffff;
    --card-border: #e8eaef;
    --card-shadow: 0 1px 3px rgba(20, 24, 35, .06), 0 6px 18px rgba(20, 24, 35, .05);
    --card-shadow-hover: 0 8px 24px rgba(79, 124, 255, .18);
    --text-strong: #1f2430;
    --text: #2c3340;
    --muted: #8b93a3;
    --accent: #4f7cff;
    --accent-soft: rgba(79, 124, 255, .10);
    --divider: #eceef3;
    --desc: #7a8290;

    box-sizing: border-box;
    width: 100%;
    max-width: 1080px;
    margin: 0 auto;
    padding: 8px 4px 48px;
}

.nav-root *,
.nav-root *::before,
.nav-root *::after { box-sizing: border-box; }

.nav-root a { text-decoration: none; color: inherit; }

/* 分类区块 */
.nav-root .main { margin-left: 0; }
.nav-root #mainContent { max-width: none; margin: 0 auto; }

.nav-root .box {
    margin: 0 0 30px;
    padding: 0;
    background: transparent;
    overflow: visible;
}

/* 常用推荐 + 参考文献 并排（桌面两列，手机堆叠） */
.nav-root .box-row {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 16px;
    margin: 0 0 30px;
    align-items: stretch;
}
.nav-root .box-row > .box {
    margin-bottom: 0;
    display: flex;
    flex-direction: column;
}
.nav-root .box-row > .box > div:not(.sub-category) {
    flex: 1;
    align-content: center;
}
@media (max-width: 600px) {
    .nav-root .box-row { grid-template-columns: 1fr; }
}

.nav-root .sub-category > div {
    display: flex;
    align-items: center;
    gap: 8px;
    padding: 10px 2px 12px;
    margin-bottom: 6px;
    font-size: 17px;
    font-weight: 700;
    color: var(--text-strong);
    letter-spacing: .5px;
    border-bottom: 1px solid var(--divider);
}
.nav-root .sub-category .iconfont {
    color: var(--accent);
    font-size: 21px;
    padding-right: 0;
}

/* 卡片网格 */
.nav-root .box > div:not(.sub-category) {
    display: grid;
    grid-template-columns: repeat(2, 1fr);
    gap: 16px;
    padding: 4px 2px 0;
}

.nav-root .item {
    display: flex;
    align-items: center;
    gap: 12px;
    min-width: 0;
    margin: 0;
    padding: 15px 16px;
    background: var(--card-bg);
    border: 1px solid var(--card-border);
    border-radius: 14px;
    box-shadow: var(--card-shadow);
    transition: transform .25s ease, box-shadow .25s ease, border-color .25s ease;
    overflow: hidden;
}
.nav-root .item:hover {
    transform: translateY(-4px);
    box-shadow: var(--card-shadow-hover);
    border-color: var(--accent);
}

.nav-root .item .no-logo {
    color: var(--text);
    font-weight: 700;
    font-size: 15px;
    line-height: 1.4;
}

.nav-root .item .logo {
    display: flex;
    align-items: center;
    gap: 10px;
    height: auto;
    position: static;
    font-size: 15px;
    font-weight: 700;
    color: var(--text);
    white-space: normal;
    overflow: visible;
    text-overflow: clip;
    padding: 0;
}
.nav-root .item .logo img {
    width: 38px;
    height: 38px;
    border-radius: 50%;
    flex: 0 0 38px;
    object-fit: cover;
    background: var(--accent-soft);
}

.nav-root .item .desc {
    color: var(--desc);
    font-size: 12.5px;
    line-height: 1.5;
    padding-top: 8px;
    height: auto;
    overflow: hidden;
    display: -webkit-box;
    -webkit-line-clamp: 2;
    -webkit-box-orient: vertical;
}

/* 小屏适配 */
@media (max-width: 600px) {
    .nav-root .box > div:not(.sub-category) {
        grid-template-columns: repeat(2, 1fr);
        gap: 12px;
    }
    .nav-root .item { padding: 12px 13px; }
}

/* ============ 暗色模式（跟随 Chic 主题 body.dark-theme） ============ */
body.dark-theme .nav-root {
    --card-bg: #23262e;
    --card-border: #33373f;
    --card-shadow: 0 1px 3px rgba(0, 0, 0, .35), 0 6px 18px rgba(0, 0, 0, .25);
    --card-shadow-hover: 0 8px 24px rgba(110, 168, 254, .25);
    --text-strong: #eef1f6;
    --text: #d6dae2;
    --muted: #8a93a3;
    --accent: #6ea8fe;
    --accent-soft: rgba(110, 168, 254, .14);
    --divider: #343842;
    --desc: #9aa2b1;
}
body.dark-theme .nav-root .item:hover { border-color: var(--accent); }