/* ============================================================
 * 响应式样式 - Step 2 版本
 * 适配手机 (≤768px) / 平板 (≤1024px) / PC (>1024px)
 * ============================================================ */

/* ---------- 平板 ---------- */
@media (max-width: 1024px) {
    .container { max-width: 90%; }

    /* 文章详情：正文变单列，TOC 浮层 */
    .article-layout {
        grid-template-columns: 1fr;
        gap: 20px;
    }
    .article-main { max-width: 100%; }
    .article-toc {
        position: fixed;
        top: 60px;
        left: 0;
        width: 280px;
        max-height: calc(100vh - 60px);
        z-index: 50;
        transform: translateX(-110%);
        transition: transform .25s ease;
        border-radius: 0 10px 10px 0;
        box-shadow: 4px 0 20px rgba(0,0,0,.1);
    }
    .article-toc.open { transform: translateX(0); }
    .toc-fab { display: block; }

    .article-title { font-size: 24px; }
    .article-content { padding: 24px; }
}

/* ---------- 手机 ---------- */
@media (max-width: 768px) {
    /* 导航折叠 */
    .mobile-menu-btn { display: block; margin-left: auto; }

    .site-nav {
        display: none;
        position: absolute;
        top: 60px;
        left: 0;
        right: 0;
        background: #fff;
        border-bottom: 1px solid #eee;
        box-shadow: 0 4px 8px rgba(0,0,0,.08);
    }
    .site-nav.active { display: block; }
    .site-nav ul {
        flex-direction: column;
        gap: 0;
    }
    .site-nav li {
        border-bottom: 1px solid #f0f0f0;
    }
    .site-nav a {
        display: block;
        padding: 12px 20px;
    }

    /* 移动端子菜单：折叠面板 */
    .site-nav li.has-sub {
        position: relative;
    }
    .site-nav > ul > li.has-sub > a::after {
        content: none;  /* 移动端不用 CSS 箭头，用按钮 */
    }
    .site-nav .sub-toggle {
        display: block;
        position: absolute;
        right: 12px;
        top: 50%;
        transform: translateY(-50%);
        width: 32px;
        height: 32px;
        border: none;
        background: transparent;
        color: #64748b;
        font-size: 14px;
        cursor: pointer;
    }
    .site-nav .sub-nav {
        display: none;
        position: static;
        transform: none;
        min-width: 0;
        box-shadow: none;
        border-radius: 0;
        padding: 0;
        background: #fafafa;
    }
    .site-nav .sub-nav::before { display: none; }
    .site-nav .sub-nav li {
        border-bottom: none;
    }
    .site-nav .sub-nav li a {
        padding: 10px 20px 10px 40px;
        font-size: 13px;
    }
    /* 子菜单展开状态 */
    .site-nav li.has-sub.open > .sub-nav {
        display: block;
    }
    .site-nav li.has-sub.open > .sub-toggle {
        transform: translateY(-50%) rotate(180deg);
    }
    /* 服务商城：移动端子菜单默认展开（无展开按钮） */
    .site-nav li.has-sub.nav-svc .sub-nav {
        display: block;
    }

    .header-search { display: none; }

    /* Hero 区 */
    .hero-section { padding: 40px 0; }
    .hero-section h1 { font-size: 22px; }
    .hero-section p { font-size: 14px; }

    /* 分类网格 */
    .categories-grid {
        grid-template-columns: repeat(2, 1fr);
        gap: 10px;
    }
    .category-card { padding: 14px; }
    .category-card h3 { font-size: 14px; }

    /* 文章卡片 */
    .article-item { padding: 16px; }
    .article-item h3 { font-size: 16px; }

    /* 文章详情 */
    .article-title { font-size: 20px; }
    .article-content { padding: 18px; font-size: 15px; line-height: 1.8; }

    /* 上下篇 */
    .article-nav { flex-direction: column; }
    .article-nav a { text-align: left; }

    /* 页脚 */
    .footer-inner { flex-direction: column; gap: 20px; }
}

/* ---------- 小屏手机 ---------- */
@media (max-width: 480px) {
    .categories-grid { grid-template-columns: 1fr; }

    .article-meta { flex-wrap: wrap; gap: 8px; }

    .pagination ul { gap: 4px; }
    .pagination a, .pagination span { padding: 4px 8px; font-size: 12px; }

    .error-content h1 { font-size: 80px; }
}