/* ===== 基础 ===== */
* { box-sizing: border-box; margin: 0; padding: 0; }

:root {
    --primary: #1a6fe0;
    --primary-dark: #1359b8;
    --dark: #16233a;
    --text: #2b3445;
    --muted: #7a8699;
    --bg: #f5f7fb;
    --card: #ffffff;
    --border: #e4e9f2;
    --radius: 12px;
    --shadow: 0 2px 12px rgba(22, 35, 58, .08);
}

html { font-size: 16px; }
body {
    font-family: "Segoe UI", "Microsoft YaHei", "PingFang SC", sans-serif;
    color: var(--text);
    background: var(--bg);
    line-height: 1.6;
}
a { color: var(--primary); text-decoration: none; }
a:hover { color: var(--primary-dark); }

.container { max-width: 1160px; margin: 0 auto; padding: 0 20px; }
.section { padding: 40px 20px; }
.narrow { max-width: 720px; }
.muted { color: var(--muted); font-size: .9rem; }
.inline-form { display: inline; }

/* ===== 顶部导航 ===== */
.site-header {
    background: #fff;
    border-bottom: 1px solid var(--border);
    position: sticky; top: 0; z-index: 100;
}
.header-inner { display: flex; align-items: center; gap: 32px; height: 64px; }
.brand { display: flex; align-items: center; gap: 10px; color: var(--dark); font-weight: 700; font-size: 1.15rem; }
.brand-logo {
    width: 36px; height: 36px; border-radius: 9px;
    object-fit: contain; display: block;
}
.main-nav { display: flex; gap: 26px; flex: 1; }
.main-nav a { color: var(--text); font-weight: 500; padding: 4px 0; border-bottom: 2px solid transparent; }
.main-nav a:hover { color: var(--primary); }
.header-actions { display: flex; align-items: center; gap: 10px; }

/* ===== 按钮 ===== */
.btn {
    display: inline-block; padding: 9px 20px; border-radius: 8px;
    border: 1px solid transparent; cursor: pointer; font-size: .95rem;
    font-weight: 500; text-align: center; transition: all .15s;
    background: none;
}
.btn-primary { background: var(--primary); color: #fff; }
.btn-primary:hover { background: var(--primary-dark); color: #fff; }
.btn-outline { border-color: var(--primary); color: var(--primary); }
.btn-outline:hover { background: var(--primary); color: #fff; }
.btn-light { background: #fff; color: var(--primary); }
.btn-light:hover { background: #eaf2fd; color: var(--primary-dark); }
.btn-ghost { color: var(--muted); border-color: var(--border); }
.btn-ghost:hover { color: var(--text); border-color: var(--muted); }
.btn-danger { background: #e5484d; color: #fff; }
.btn-danger:hover { background: #c93a3f; color: #fff; }
.btn-lg { padding: 13px 34px; font-size: 1.05rem; border-radius: 10px; }
.btn-sm { padding: 4px 12px; font-size: .82rem; border-radius: 6px; }
.btn-block { display: block; width: 100%; }

/* ===== 首页 Hero ===== */
.hero {
    background: linear-gradient(135deg, #16233a 0%, #1a4a8f 60%, #1a6fe0 100%);
    color: #fff; text-align: center; padding: 90px 20px 100px;
}
.hero h1 { font-size: 2.6rem; margin-bottom: 12px; letter-spacing: 1px; }
.hero-slogan { font-size: 1.15rem; opacity: .85; margin-bottom: 34px; }
.hero-actions { display: flex; justify-content: center; gap: 16px; }

/* ===== 页面横幅 ===== */
.page-banner {
    background: linear-gradient(135deg, #16233a, #1a4a8f);
    color: #fff; text-align: center; padding: 52px 20px;
}
.page-banner h1 { font-size: 1.8rem; margin-bottom: 8px; }
.page-banner p { opacity: .8; }

/* ===== 筛选工具栏 ===== */
.toolbar { display: flex; flex-wrap: wrap; gap: 16px; justify-content: space-between; align-items: center; margin-bottom: 28px; }
.filter-tabs { display: flex; flex-wrap: wrap; gap: 8px; }
.filter-tab {
    padding: 7px 18px; border-radius: 20px; background: #fff;
    border: 1px solid var(--border); color: var(--text); font-size: .92rem;
}
.filter-tab:hover { border-color: var(--primary); color: var(--primary); }
.filter-tab.active { background: var(--primary); color: #fff; border-color: var(--primary); }
.search-form { display: flex; gap: 8px; }
.search-form input {
    width: 260px; padding: 8px 14px; border: 1px solid var(--border);
    border-radius: 8px; background: #fff; outline: none;
}
.search-form input:focus { border-color: var(--primary); }

/* ===== 卡片 ===== */
.section-head { display: flex; justify-content: space-between; align-items: center; margin-bottom: 22px; }
.section-head h2 { font-size: 1.35rem; color: var(--dark); }
.more-link { font-size: .92rem; font-weight: 500; }

.card-grid { display: grid; grid-template-columns: repeat(auto-fill, minmax(330px, 1fr)); gap: 20px; }
.card { background: var(--card); border-radius: var(--radius); box-shadow: var(--shadow); overflow: hidden; display: flex; flex-direction: column; }
.card-body { padding: 20px 20px 12px; flex: 1; }
.card-title-row { display: flex; align-items: center; gap: 10px; margin-bottom: 8px; }
.card-title-row h3 { font-size: 1.08rem; color: var(--dark); }
.card-meta { display: flex; flex-wrap: wrap; gap: 14px; color: var(--muted); font-size: .84rem; margin-bottom: 10px; }
.card-desc { color: var(--text); font-size: .92rem; display: -webkit-box; -webkit-line-clamp: 2; -webkit-box-orient: vertical; overflow: hidden; }
.card-footer { padding: 0 20px 20px; }

.chip {
    background: #eaf2fd; color: var(--primary); padding: 2px 10px;
    border-radius: 12px; font-size: .8rem;
}
.badge { padding: 2px 8px; border-radius: 6px; font-size: .75rem; }
.badge-blue { background: #eaf2fd; color: var(--primary); }
.badge-orange { background: #fdf1e3; color: #c47a10; }

.empty-state {
    background: #fff; border: 1px dashed var(--border); border-radius: var(--radius);
    text-align: center; padding: 60px 20px; color: var(--muted);
}
.empty-state h1 { color: var(--dark); margin-bottom: 8px; }

/* ===== 视频卡片 ===== */
.video-grid { display: grid; grid-template-columns: repeat(auto-fill, minmax(300px, 1fr)); gap: 20px; }
.video-card {
    background: var(--card); border-radius: var(--radius); overflow: hidden;
    box-shadow: var(--shadow); color: var(--text); transition: transform .15s, box-shadow .15s;
    display: flex; flex-direction: column;
}
.video-card:hover { transform: translateY(-3px); box-shadow: 0 6px 20px rgba(22,35,58,.14); color: var(--text); }
.video-thumb {
    height: 170px; background: linear-gradient(135deg, #22314e, #1a4a8f);
    display: flex; align-items: center; justify-content: center;
}
.play-icon {
    width: 58px; height: 58px; border-radius: 50%;
    background: rgba(255,255,255,.18); backdrop-filter: blur(2px);
    color: #fff; font-size: 1.5rem; display: flex; align-items: center; justify-content: center;
    padding-left: 5px;
}
.video-info { padding: 16px 18px 18px; }
.video-info h3 { font-size: 1.02rem; color: var(--dark); margin-bottom: 6px; }
.video-desc { color: var(--muted); font-size: .88rem; display: -webkit-box; -webkit-line-clamp: 2; -webkit-box-orient: vertical; overflow: hidden; }

/* ===== 视频播放页 ===== */
.watch-layout { display: grid; grid-template-columns: 1fr 300px; gap: 28px; align-items: start; }
.player-wrap { background: #000; border-radius: var(--radius); overflow: hidden; }
.player-wrap video { display: block; width: 100%; max-height: 560px; }
.watch-info { background: #fff; border-radius: var(--radius); box-shadow: var(--shadow); padding: 22px; margin-top: 18px; }
.watch-info h1 { font-size: 1.4rem; color: var(--dark); margin-bottom: 10px; }
.watch-desc { margin: 12px 0 18px; }
.watch-side { background: #fff; border-radius: var(--radius); box-shadow: var(--shadow); padding: 20px; }
.watch-side h2 { font-size: 1.05rem; color: var(--dark); margin-bottom: 14px; }
.related-item {
    display: flex; flex-direction: column; gap: 3px; padding: 10px 12px;
    border-radius: 8px; margin-bottom: 6px; color: var(--text);
}
.related-item:hover { background: var(--bg); color: var(--text); }
.related-item strong { font-size: .95rem; font-weight: 600; }

/* ===== 分类面板 ===== */
.category-columns { display: grid; grid-template-columns: 1fr 1fr; gap: 20px; }
.category-panel { background: #fff; border-radius: var(--radius); box-shadow: var(--shadow); padding: 24px; }
.category-panel h3 { color: var(--dark); margin-bottom: 12px; font-size: 1.05rem; }
.category-panel ul { list-style: none; }
.category-panel li { padding: 6px 0; border-bottom: 1px solid var(--border); }
.category-panel li:last-child { border-bottom: none; }

/* ===== 管理后台 ===== */
.admin-nav { background: var(--dark); }
.admin-nav .container { display: flex; gap: 6px; }
.admin-nav a { color: rgba(255,255,255,.75); padding: 12px 18px; font-size: .95rem; }
.admin-nav a:hover { color: #fff; background: rgba(255,255,255,.08); }

.stat-grid { display: grid; grid-template-columns: repeat(auto-fit, minmax(180px, 1fr)); gap: 18px; margin: 20px 0 26px; }
.stat-card {
    background: #fff; border-radius: var(--radius); box-shadow: var(--shadow);
    padding: 24px; text-align: center;
}
.stat-num { display: block; font-size: 2rem; font-weight: 700; color: var(--primary); }
.stat-label { color: var(--muted); font-size: .9rem; }

.admin-actions { display: flex; gap: 12px; margin-bottom: 28px; flex-wrap: wrap; }
.admin-columns { display: grid; grid-template-columns: 1fr 1fr; gap: 20px; }
.admin-panel { background: #fff; border-radius: var(--radius); box-shadow: var(--shadow); padding: 22px; }
.admin-panel h2 { font-size: 1.05rem; color: var(--dark); margin-bottom: 12px; }
.admin-row {
    display: flex; justify-content: space-between; align-items: center;
    padding: 9px 4px; border-bottom: 1px solid var(--border); gap: 10px;
}
.admin-row:last-child { border-bottom: none; }

/* ===== 表格 ===== */
.data-table { width: 100%; background: #fff; border-radius: var(--radius); box-shadow: var(--shadow); border-collapse: collapse; overflow: hidden; }
.data-table th, .data-table td { padding: 13px 16px; text-align: left; font-size: .93rem; }
.data-table thead th { background: var(--bg); color: var(--dark); font-weight: 600; }
.data-table tbody tr { border-top: 1px solid var(--border); }
.data-table tbody tr:hover { background: #fafcff; }
.table-actions { display: flex; gap: 8px; align-items: center; }

/* 用户管理：内联重置密码 */
.reset-details { position: relative; }
.reset-details summary { list-style: none; cursor: pointer; display: inline-block; }
.reset-details summary::-webkit-details-marker { display: none; }
.reset-details[open] .form-row {
    position: absolute; left: 0; top: 36px; z-index: 20;
    background: #fff; padding: 10px; border-radius: 8px;
    box-shadow: 0 8px 24px rgba(22,35,58,.18); border: 1px solid var(--border);
}

/* ===== 表单 ===== */
.admin-form { background: #fff; border-radius: var(--radius); box-shadow: var(--shadow); padding: 28px; display: flex; flex-direction: column; gap: 8px; }
.admin-form label { font-weight: 600; color: var(--dark); margin-top: 10px; }
.admin-form input[type="text"], .admin-form input[type="number"],
.admin-form select, .admin-form textarea {
    padding: 10px 13px; border: 1px solid var(--border); border-radius: 8px;
    font-size: .95rem; font-family: inherit; background: #fff; outline: none; width: 100%;
}
.admin-form input:focus, .admin-form select:focus, .admin-form textarea:focus { border-color: var(--primary); }
.admin-form button[type="submit"] { margin-top: 20px; }
.admin-form input[type="file"] { padding: 8px 0; }

.category-form { margin-bottom: 26px; padding: 22px; }
.category-form h2 { font-size: 1.05rem; color: var(--dark); margin-bottom: 14px; }
.form-row { display: flex; gap: 10px; flex-wrap: wrap; }
.form-row input, .form-row select {
    padding: 9px 13px; border: 1px solid var(--border); border-radius: 8px; outline: none; font-family: inherit;
}
.form-row input[name="name"] { flex: 1; min-width: 180px; }
.form-row input:focus, .form-row select:focus { border-color: var(--primary); }

.validation-summary { color: #e5484d; }
.validation-summary:empty { display: none; }
.validation-summary ul { list-style: none; margin: 8px 0; }

/* ===== 提示 ===== */
.toast { padding: 13px 18px; border-radius: 8px; margin-bottom: 20px; font-size: .95rem; }
.toast-success { background: #e7f7ee; color: #1d7a4d; border: 1px solid #b7e4cc; }
.toast-error { background: #fdecec; color: #c0392b; border: 1px solid #f5c6c6; }

/* ===== 登录页 ===== */
.login-body {
    display: flex; align-items: center; justify-content: center; min-height: 100vh;
    background: linear-gradient(135deg, #16233a, #1a4a8f);
}
.login-card {
    background: #fff; border-radius: 16px; padding: 40px 38px; width: 400px; max-width: 92vw;
    box-shadow: 0 18px 50px rgba(0,0,0,.3); text-align: center;
}
.login-card h1 { font-size: 1.4rem; color: var(--dark); margin-bottom: 6px; }
.login-card p.login-tip { margin-top: 18px; }
.login-card form { display: flex; flex-direction: column; gap: 6px; text-align: left; margin-top: 20px; }
.login-card label { font-weight: 600; color: var(--dark); }
.login-card input {
    padding: 11px 13px; border: 1px solid var(--border); border-radius: 8px;
    font-size: .98rem; outline: none;
}
.login-card input:focus { border-color: var(--primary); }
.login-card button { margin-top: 16px; }

/* ===== 页脚 ===== */
.site-footer { background: var(--dark); color: rgba(255,255,255,.6); text-align: center; padding: 26px 0; margin-top: 40px; font-size: .88rem; }

/* ===== 响应式 ===== */
@media (max-width: 900px) {
    .watch-layout, .admin-columns, .category-columns { grid-template-columns: 1fr; }
    .header-inner { gap: 14px; }
    .main-nav { gap: 14px; }
}
@media (max-width: 640px) {
    .header-inner { flex-wrap: wrap; height: auto; padding: 10px 0; }
    .toolbar { flex-direction: column; align-items: stretch; }
    .search-form input { width: 100%; flex: 1; }
    .hero h1 { font-size: 1.9rem; }
}