/* ====== 前台样式（白 + 浅蓝主题） ====== */
* { margin: 0; padding: 0; box-sizing: border-box; }
:root {
  --primary: #40A6F8;
  --primary-dark: #2196F0;
  --primary-light: #EAF5FE;
  --bg: #ffffff;
  --card: #ffffff;
  --text: #243342;
  --text2: #7b8ca3;
  --border: #e6eef7;
  --radius: 14px;
  --shadow: 0 2px 14px rgba(64, 166, 248, .07);
  --shadow-lg: 0 10px 32px rgba(64, 166, 248, .14);
}
html { scroll-behavior: smooth; }
body { font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", "PingFang SC", "Microsoft YaHei", sans-serif; background: var(--bg); color: var(--text); line-height: 1.7; }
a { color: var(--primary-dark); text-decoration: none; }
img { max-width: 100%; }
.container { max-width: 1160px; margin: 0 auto; padding: 0 20px; }
.muted { color: var(--text2); }

/* 公告条（浅蓝） */
.announce { background: var(--primary-light); color: #3178b5; font-size: 14px; border-bottom: 1px solid var(--border); }
.ann-inner { display: flex; align-items: center; gap: 10px; padding: 9px 20px; }
.ann-icon { color: var(--primary-dark); }
.ann-text { flex: 1; overflow: hidden; text-overflow: ellipsis; white-space: nowrap; }
.ann-text a { color: #3178b5; text-decoration: underline; }
.ann-close { background: none; border: none; color: #7ba8cf; font-size: 18px; cursor: pointer; }
.ann-close:hover { color: var(--primary-dark); }

/* 顶栏 */
.site-header { position: sticky; top: 0; z-index: 100; background: rgba(255,255,255,.94); backdrop-filter: blur(10px); border-bottom: 1px solid var(--border); }
.header-inner { display: flex; align-items: center; gap: 26px; height: 62px; }
.logo { display: flex; align-items: center; gap: 10px; font-weight: 800; font-size: 19px; color: var(--text); flex-shrink: 0; }
.logo-badge { width: 34px; height: 34px; border-radius: 10px; color: #fff; display: inline-flex; align-items: center; justify-content: center; font-size: 18px; box-shadow: 0 3px 10px rgba(64,166,248,.35); }
.logo-img { height: 34px; }
.main-nav { display: flex; align-items: center; gap: 4px; flex: 1; }
.main-nav > a { padding: 8px 13px; border-radius: 9px; color: #4b5c70; font-size: 15px; font-weight: 500; transition: .15s; white-space: nowrap; }
.main-nav > a:hover { background: var(--primary-light); color: var(--primary-dark); }
.main-nav > a.active { background: var(--primary); color: #fff; }
.nav-search { margin-left: auto; display: flex; align-items: center; background: #f4f9fe; border: 1px solid var(--border); border-radius: 99px; padding: 3px 4px 3px 14px; }
.nav-search input { border: none; outline: none; background: transparent; width: 130px; font-size: 13px; color: var(--text); }
.nav-search button { border: none; background: var(--primary); color: #fff; width: 28px; height: 28px; border-radius: 50%; cursor: pointer; font-size: 12px; }
.nav-toggle { display: none; background: none; border: none; font-size: 24px; cursor: pointer; color: var(--text); margin-left: auto; }

/* Hero（浅蓝渐变 + 深色文字） */
.hero { background: linear-gradient(180deg, #E3F1FE 0%, #F3F9FF 55%, #ffffff 100%); color: var(--text); text-align: center; padding: 62px 0 66px; position: relative; overflow: hidden; }
.hero::before { content: ''; position: absolute; width: 420px; height: 420px; border-radius: 50%; background: radial-gradient(circle, rgba(64,166,248,.14), transparent 65%); top: -180px; right: -120px; }
.hero::after { content: ''; position: absolute; width: 320px; height: 320px; border-radius: 50%; background: radial-gradient(circle, rgba(64,166,248,.10), transparent 65%); bottom: -150px; left: -80px; }
.hero h1 { font-size: 34px; font-weight: 800; letter-spacing: 1px; color: #1d3a56; }
.hero p { margin: 12px auto 26px; color: #5e7a95; max-width: 640px; font-size: 15px; }
.hero-search { display: flex; max-width: 560px; margin: 0 auto; background: #fff; border: 1.5px solid #cfe6fb; border-radius: 99px; padding: 5px 5px 5px 22px; box-shadow: 0 8px 28px rgba(64,166,248,.16); position: relative; z-index: 1; }
.hero-search:focus-within { border-color: var(--primary); }
.hero-search input { flex: 1; border: none; outline: none; font-size: 15px; color: var(--text); background: transparent; }
.hero-search button { border: none; background: var(--primary); color: #fff; padding: 10px 30px; border-radius: 99px; font-size: 15px; cursor: pointer; font-weight: 600; transition: .2s; }
.hero-search button:hover { background: var(--primary-dark); }
.hero-tags { margin-top: 16px; font-size: 13px; color: #7b93ab; position: relative; z-index: 1; }
.hero-tags a { color: #4a90cf; margin: 0 6px; border-bottom: 1px dashed #a9cdec; }

/* 区块 */
.section { margin: 38px 0; }
.sec-head { display: flex; align-items: baseline; gap: 12px; margin-bottom: 20px; }
.sec-head h2 { font-size: 22px; color: #1d3a56; }
.sec-sub { color: var(--text2); font-size: 13px; }

/* 分类卡片 */
.cat-grid { display: grid; grid-template-columns: repeat(auto-fill, minmax(200px, 1fr)); gap: 16px; }
.cat-card { --c: var(--primary); background: var(--card); border-radius: var(--radius); padding: 22px 18px; display: flex; flex-direction: column; gap: 4px; box-shadow: var(--shadow); border: 1px solid var(--border); transition: .2s; }
.cat-card:hover { transform: translateY(-4px); box-shadow: var(--shadow-lg); border-color: color-mix(in srgb, var(--c) 45%, white); }
.cat-icon { font-size: 30px; margin-bottom: 6px; }
.cat-name { font-weight: 700; font-size: 16px; color: var(--text); }
.cat-desc { font-size: 12.5px; color: var(--text2); display: -webkit-box; -webkit-line-clamp: 2; -webkit-box-orient: vertical; overflow: hidden; min-height: 38px; }
.cat-count { margin-top: 8px; font-size: 12px; color: var(--primary-dark); font-weight: 600; }

/* 教程卡片 */
.card-grid { display: grid; grid-template-columns: repeat(auto-fill, minmax(258px, 1fr)); gap: 18px; }
.t-card { background: var(--card); border-radius: var(--radius); overflow: hidden; box-shadow: var(--shadow); transition: .2s; display: flex; flex-direction: column; border: 1px solid var(--border); }
.t-card:hover { transform: translateY(-4px); box-shadow: var(--shadow-lg); border-color: #bcdcf8; }
.card-cover { height: 150px; overflow: hidden; background: #f4f9fe; }
.card-cover img { width: 100%; height: 100%; object-fit: cover; transition: .3s; }
.t-card:hover .card-cover img { transform: scale(1.05); }
.cover-fallback { display: flex; align-items: center; justify-content: center; font-size: 46px; background: linear-gradient(135deg, color-mix(in srgb, var(--c) 14%, white), color-mix(in srgb, var(--c) 38%, white)); }
.card-body { padding: 15px 16px 14px; display: flex; flex-direction: column; gap: 8px; flex: 1; }
.card-cats { display: flex; gap: 6px; align-items: center; }
.cat-badge { --c: var(--primary); display: inline-block; font-size: 11.5px; color: var(--primary-dark); background: color-mix(in srgb, var(--c) 12%, white); padding: 2px 9px; border-radius: 99px; font-weight: 600; }
.pin-badge { display: inline-block; font-size: 11.5px; color: #d97706; background: #fdf3df; padding: 2px 9px; border-radius: 99px; font-weight: 600; }
.card-title { font-size: 15.5px; line-height: 1.45; color: var(--text); display: -webkit-box; -webkit-line-clamp: 2; -webkit-box-orient: vertical; overflow: hidden; }
.card-excerpt { font-size: 13px; color: var(--text2); display: -webkit-box; -webkit-line-clamp: 2; -webkit-box-orient: vertical; overflow: hidden; }
.card-meta { margin-top: auto; display: flex; gap: 14px; font-size: 12px; color: #a3b3c7; }

/* 列表行 */
.list-wrap { display: flex; flex-direction: column; gap: 12px; }
.t-row { display: flex; gap: 16px; background: var(--card); border-radius: var(--radius); padding: 17px 18px; box-shadow: var(--shadow); transition: .2s; align-items: flex-start; border: 1px solid var(--border); }
.t-row:hover { transform: translateX(4px); box-shadow: var(--shadow-lg); border-color: #bcdcf8; }
.row-icon { --c: var(--primary); width: 46px; height: 46px; border-radius: 12px; background: color-mix(in srgb, var(--c) 12%, white); display: flex; align-items: center; justify-content: center; font-size: 22px; flex-shrink: 0; }
.row-body { flex: 1; min-width: 0; }
.row-body h3 { font-size: 15.5px; color: var(--text); display: flex; align-items: center; gap: 8px; flex-wrap: wrap; }
.row-body p { font-size: 13px; color: var(--text2); margin-top: 3px; display: -webkit-box; -webkit-line-clamp: 1; -webkit-box-orient: vertical; overflow: hidden; }
.row-meta { display: flex; gap: 14px; font-size: 12px; color: #a3b3c7; margin-top: 6px; }

/* 分页 */
.pager { display: flex; justify-content: center; gap: 8px; margin: 30px 0 10px; flex-wrap: wrap; }
.pg-btn { padding: 7px 15px; border-radius: 9px; background: #fff; border: 1px solid var(--border); color: var(--text); font-size: 13.5px; box-shadow: var(--shadow); }
.pg-btn:hover:not(.disabled):not(.active) { border-color: var(--primary); color: var(--primary-dark); }
.pg-btn.active { background: var(--primary); border-color: var(--primary); color: #fff; }
.pg-btn.disabled { opacity: .45; cursor: default; }
.pg-dots { align-self: center; color: var(--text2); }

/* 页面头（浅色） */
.page-head { --c: var(--primary); background: linear-gradient(180deg, color-mix(in srgb, var(--c) 12%, white), #ffffff); padding: 36px 0 40px; border-bottom: 1px solid var(--border); }
.page-head.plain { background: #fff; border-bottom: 1px solid var(--border); padding: 30px 0; }
.page-head .crumb a, .page-head .crumb span { color: #7b93ab; }
.page-head.plain .crumb a, .page-head.plain .crumb span { color: var(--text2); }
.page-head-main { display: flex; align-items: center; gap: 18px; }
.ph-icon { width: 64px; height: 64px; border-radius: 18px; background: color-mix(in srgb, var(--c) 14%, white); border: 1px solid color-mix(in srgb, var(--c) 25%, white); display: flex; align-items: center; justify-content: center; font-size: 32px; }
.page-head h1 { font-size: 26px; color: #1d3a56; }
.page-head p { color: #6d87a0; font-size: 14px; margin-top: 4px; }
.ph-count { margin-left: auto; background: #fff; border: 1px solid var(--border); color: var(--primary-dark); padding: 6px 16px; border-radius: 99px; font-size: 13px; font-weight: 600; }
.crumb { font-size: 13px; margin-bottom: 14px; }
.crumb a { color: inherit; }
.article-wrap .crumb { color: var(--text2); margin: 18px 0; }
.article-wrap .crumb a { color: var(--text2); }
.search-title { font-size: 22px; color: #1d3a56; margin-bottom: 4px; }

/* 文章页 */
.article-card { background: var(--card); border-radius: var(--radius); box-shadow: var(--shadow); padding: 34px 38px; border: 1px solid var(--border); }
.art-title { font-size: 26px; line-height: 1.4; color: #1d3a56; }
.art-meta { display: flex; align-items: center; gap: 16px; color: #a3b3c7; font-size: 13px; margin: 14px 0 8px; padding-bottom: 18px; border-bottom: 1px solid var(--border); flex-wrap: wrap; }
.art-content { padding-top: 10px; font-size: 15.5px; word-break: break-word; }
.art-content h2 { font-size: 21px; margin: 28px 0 12px; padding-left: 12px; border-left: 4px solid var(--primary); color: #1d3a56; }
.art-content h3 { font-size: 17.5px; margin: 22px 0 10px; color: #2a4a68; }
.art-content p { margin: 10px 0; color: #3d4f63; }
.art-content ul, .art-content ol { padding-left: 24px; margin: 10px 0; color: #3d4f63; }
.art-content li { margin: 5px 0; }
.art-content img { border-radius: 10px; box-shadow: var(--shadow); margin: 8px 0; }
.art-content video { display: block; width: 100%; max-width: 720px; margin: 14px auto; border-radius: 12px; background: #000; box-shadow: var(--shadow-lg); }

/* 视频查看按钮（文字底部右下角） */
.video-cta { display: flex; align-items: center; justify-content: center; gap: 8px; width: fit-content; margin: 16px 0 6px auto; padding: 11px 24px; border: none; border-radius: 99px; background: linear-gradient(135deg, var(--primary), var(--primary-dark)); color: #fff; font-size: 14.5px; font-weight: 600; cursor: pointer; box-shadow: 0 6px 18px rgba(64, 166, 248, .35); transition: .2s; }
.video-cta:hover { transform: translateY(-2px); box-shadow: 0 10px 26px rgba(64, 166, 248, .45); }
.video-cta .vc-ico { font-size: 11px; }

/* 视频弹窗 */
.video-modal { position: fixed; inset: 0; z-index: 999; display: none; }
.video-modal.open { display: block; }
.vm-backdrop { position: absolute; inset: 0; background: rgba(8, 18, 30, .74); backdrop-filter: blur(3px); }
.vm-box { position: absolute; left: 50%; top: 50%; transform: translate(-50%, -50%); width: min(860px, 94vw); background: #000; border-radius: 16px; padding: 10px; box-shadow: 0 24px 70px rgba(0, 0, 0, .55); }
.vm-box video { display: block; width: 100%; max-height: 76vh; border-radius: 10px; background: #000; }
.vm-close { position: absolute; top: -14px; right: -14px; width: 36px; height: 36px; border-radius: 50%; border: none; background: #fff; color: #243342; font-size: 20px; line-height: 1; cursor: pointer; box-shadow: 0 4px 14px rgba(0, 0, 0, .3); }
.vm-close:hover { background: #ffe8e8; color: #d33; }

/* 返回上一页 / 回到首页 */
.page-actions { display: flex; gap: 10px; flex-wrap: wrap; margin: 14px 0; }
.pa-btn { display: inline-flex; align-items: center; gap: 6px; padding: 8px 18px; border-radius: 99px; background: #fff; border: 1px solid #dbe7f3; color: #3d5a76; font-size: 13.5px; font-weight: 500; text-decoration: none; box-shadow: 0 2px 8px rgba(42, 130, 200, .07); transition: .18s; }
.pa-btn:hover { border-color: var(--primary); color: var(--primary); transform: translateY(-1px); box-shadow: 0 5px 14px rgba(42, 130, 200, .14); }
.pa-btn.pa-home { background: linear-gradient(135deg, var(--primary), var(--primary-dark)); border-color: transparent; color: #fff; }
.pa-btn.pa-home:hover { color: #fff; box-shadow: 0 6px 18px rgba(64, 166, 248, .35); }

/* 联系我们卡片 */
.contact-card { margin-top: 22px; padding: 18px 20px; border-radius: 12px; background: linear-gradient(135deg, var(--primary-light), #fff); border: 1px solid var(--primary-light); }
.contact-card h3 { margin: 0 0 12px; font-size: 16px; color: #24466b; }
.contact-list { display: grid; grid-template-columns: repeat(auto-fit, minmax(240px, 1fr)); gap: 10px; }
.contact-item { display: flex; align-items: center; gap: 10px; background: rgba(255, 255, 255, .85); border-radius: 9px; padding: 10px 14px; border: 1px solid #e6eef7; }
.ci-label { flex: none; font-size: 12.5px; color: var(--primary-dark); font-weight: 600; padding: 3px 10px; border-radius: 99px; background: var(--primary-light); }
.ci-value { font-size: 14px; color: #33475c; word-break: break-all; }

/* 搜索联想下拉 */
.live-search { position: relative; }
.search-suggest { position: absolute; top: calc(100% + 8px); left: 0; right: 0; z-index: 60; background: #fff; border-radius: 14px; box-shadow: 0 14px 44px rgba(20, 50, 90, .18); border: 1px solid #e4eef8; overflow: hidden; text-align: left; max-width: 560px; margin: 0 auto; }
.hero-search .search-suggest { left: 50%; transform: translateX(-50%); width: min(560px, 94%); right: auto; }
.ss-head { padding: 10px 16px; font-size: 12.5px; color: #7b8ea3; border-bottom: 1px solid #eef4fa; background: #f8fbfe; }
.ss-item { display: flex; align-items: center; gap: 10px; padding: 11px 16px; text-decoration: none; border-bottom: 1px solid #f2f7fc; transition: .15s; }
.ss-item:hover { background: var(--primary-light); }
.ss-cat { flex: none; font-size: 11px; color: var(--primary-dark); background: var(--primary-light); border-radius: 99px; padding: 2px 9px; font-weight: 600; }
.ss-title { flex: 1; font-size: 14px; color: #2c3e50; overflow: hidden; text-overflow: ellipsis; white-space: nowrap; }
.ss-title b { color: var(--primary); }
.ss-meta { flex: none; font-size: 12px; color: #9db0c3; }
.ss-all { display: block; padding: 10px 16px; font-size: 13px; color: var(--primary); text-decoration: none; text-align: center; background: #f8fbfe; font-weight: 500; }
.ss-all:hover { background: var(--primary-light); }
.ss-empty { padding: 22px 16px; text-align: center; font-size: 14px; color: #51667c; line-height: 1.9; }
.ss-empty span { font-size: 12.5px; color: #93a7ba; }
.art-content blockquote { border-left: 4px solid var(--primary); background: var(--primary-light); padding: 12px 18px; border-radius: 0 10px 10px 0; margin: 14px 0; color: #3d5a76; }
.art-content pre { background: #101b28; color: #dbe7f3; padding: 16px 18px; border-radius: 10px; overflow-x: auto; margin: 14px 0; font-size: 13.5px; }
.art-content code { background: #eff6fd; padding: 2px 7px; border-radius: 6px; font-size: .9em; color: #1d7ad6; }
.art-content pre code { background: none; color: inherit; padding: 0; }
.art-content table { border-collapse: collapse; width: 100%; margin: 14px 0; font-size: 14px; }
.art-content th, .art-content td { border: 1px solid var(--border); padding: 9px 13px; text-align: left; }
.art-content th { background: #f4f9fe; font-weight: 600; color: #2a4a68; }
.art-content hr { border: none; border-top: 1px dashed var(--border); margin: 22px 0; }
.art-content a { border-bottom: 1px dashed var(--primary); }
.tip-box { background: #edf7ff; border: 1px solid #cfe6fb; color: #2a6ea6; border-radius: 10px; padding: 12px 16px; margin: 14px 0; font-size: 14px; }
.warn-box { background: #fffaf0; border: 1px solid #fbe4b6; color: #ad6800; border-radius: 10px; padding: 12px 16px; margin: 14px 0; font-size: 14px; }
.art-tags { margin-top: 22px; display: flex; gap: 8px; flex-wrap: wrap; }
.art-tags a { font-size: 12.5px; background: #f4f9fe; color: var(--text2); padding: 4px 12px; border-radius: 99px; }
.art-tags a:hover { background: var(--primary-light); color: var(--primary-dark); }
.art-nav { display: flex; justify-content: space-between; gap: 14px; margin-top: 26px; padding-top: 20px; border-top: 1px solid var(--border); }
.art-nav-link { flex: 1; max-width: 48%; background: #f7fbff; border: 1px solid var(--border); border-radius: 12px; padding: 12px 16px; display: flex; flex-direction: column; gap: 3px; overflow: hidden; }
.art-nav-link small { color: var(--text2); font-size: 12px; }
.art-nav-link span { color: var(--text); font-size: 14px; font-weight: 600; white-space: nowrap; overflow: hidden; text-overflow: ellipsis; }
.art-nav-link.next { text-align: right; margin-left: auto; }
.art-nav-link:hover { background: var(--primary-light); border-color: #bcdcf8; }
.related h2 { font-size: 19px; margin-bottom: 14px; color: #1d3a56; }
.empty-tip { text-align: center; color: var(--text2); padding: 46px 0; background: #fff; border: 1px dashed #cfe0f0; border-radius: var(--radius); }

/* 页脚（简洁单栏） */
.site-footer { background: #f7fbff; border-top: 1px solid var(--border); margin-top: 60px; padding: 34px 0 0; }
.footer-simple { text-align: center; }
.footer-brand { display: flex; align-items: center; justify-content: center; gap: 10px; font-weight: 800; font-size: 17px; color: #1d3a56; }
.footer-about { max-width: 560px; margin: 10px auto 0; font-size: 13px; color: var(--text2); line-height: 1.8; }
.footer-fl { margin-top: 14px; font-size: 13px; color: #9db0c5; }
.footer-fl a { color: #6d87a0; margin: 0 8px; }
.footer-fl a:hover { color: var(--primary-dark); }
.footer-bottom-line { border-top: 1px solid var(--border); margin-top: 22px; padding: 16px 0; font-size: 12.5px; color: #9db0c5; display: flex; justify-content: center; gap: 18px; flex-wrap: wrap; }
.footer-bottom-line a { color: #9db0c5; }
.footer-bottom-line a:hover { color: var(--primary-dark); }

/* 返回顶部 */
.back-top { position: fixed; right: 26px; bottom: 30px; width: 44px; height: 44px; border-radius: 12px; border: none; background: var(--primary); color: #fff; font-size: 19px; cursor: pointer; box-shadow: var(--shadow-lg); opacity: 0; pointer-events: none; transition: .25s; z-index: 90; }
.back-top.show { opacity: 1; pointer-events: auto; }
.back-top:hover { background: var(--primary-dark); transform: translateY(-2px); }

/* 错误页 */
.err-page { min-height: 100vh; display: flex; align-items: center; justify-content: center; }
.err-box { text-align: center; }
.err-code { font-size: 80px; font-weight: 800; color: var(--primary); }
.btn-primary { display: inline-block; margin-top: 18px; background: var(--primary); color: #fff; padding: 10px 30px; border-radius: 99px; font-weight: 600; }

/* 响应式 */
@media (max-width: 900px) {
  .footer-grid { grid-template-columns: 1fr 1fr; }
}
@media (max-width: 768px) {
  .nav-toggle { display: block; }
  .main-nav { display: none; position: absolute; top: 62px; left: 0; right: 0; background: #fff; flex-direction: column; align-items: stretch; padding: 12px 16px 18px; gap: 6px; border-bottom: 1px solid var(--border); box-shadow: var(--shadow-lg); }
  .main-nav.open { display: flex; }
  .main-nav > a { padding: 11px 14px; }
  .nav-search { margin: 8px 0 0; }
  .nav-search input { flex: 1; width: auto; }
  .hero { padding: 44px 0 50px; }
  .hero h1 { font-size: 25px; }
  .hero p { font-size: 13.5px; padding: 0 22px; }
  .article-card { padding: 22px 18px; }
  .art-title { font-size: 21px; }
  .page-head-main { flex-wrap: wrap; }
  .card-grid { grid-template-columns: repeat(auto-fill, minmax(160px, 1fr)); gap: 12px; }
  .card-cover { height: 110px; }
  .art-content video { max-width: 100%; }
}