/* otm- 明亮浅色科技风 · OTA 测试与天线测量平台 */
:root{
  --bg:#F4F7FB;
  --surface:#FFFFFF;
  --surface-2:#EEF3F9;
  --line:#E2E9F1;
  --line-strong:#CBD5E1;
  --ink:#13243B;
  --ink-2:#41526B;
  --ink-3:#6B7A92;
  --primary:#0E6BA8;
  --primary-2:#13B5C4;
  --primary-grad:linear-gradient(135deg,#0E6BA8 0%,#13B5C4 100%);
  --ok:#1F9D6B;
  --warn:#D9822B;
  --bad:#C0392B;
  --radius:14px;
  --shadow:0 8px 26px rgba(19,52,91,.08);
  --shadow-sm:0 2px 10px rgba(19,52,91,.06);
  --h2-inset:16px;
  --h2-inset-page:48px;
  --maxw:1120px;
  --header-h:64px;
}
*{box-sizing:border-box;}
html{scroll-behavior:smooth;}
body{
  margin:0;background:var(--bg);color:var(--ink);
  font-family:"Segoe UI","PingFang SC","Microsoft YaHei",system-ui,-apple-system,sans-serif;
  font-size:16px;line-height:1.75;-webkit-font-smoothing:antialiased;
}
a{color:var(--primary);text-decoration:none;}
a:hover{color:var(--primary-2);}
img{max-width:100%;}
h1,h2,h3,h4{color:var(--ink);line-height:1.35;font-weight:700;}
h2{font-size:22px;margin:34px 0 14px;padding-left:14px;border-left:3px solid var(--primary);}
h3{font-size:18px;margin:24px 0 10px;}
p{margin:0 0 14px;}
code{background:var(--surface-2);padding:1px 6px;border-radius:6px;font-size:.92em;color:#0b5d8a;}

/* ===== 顶部固定导航 ===== */
.otm-header{position:sticky;top:0;z-index:50;height:var(--header-h);
  background:rgba(255,255,255,.92);backdrop-filter:blur(10px);
  border-bottom:1px solid var(--line);box-shadow:var(--shadow-sm);}
.otm-header .otm-bar{max-width:var(--maxw);margin:0 auto;height:100%;
  display:flex;align-items:center;gap:18px;padding:0 20px;}
.otm-logo{display:flex;align-items:center;gap:10px;font-weight:800;font-size:18px;color:var(--ink);white-space:nowrap;}
.otm-logo .otm-mark{width:30px;height:30px;border-radius:8px;background:var(--primary-grad);
  display:flex;align-items:center;justify-content:center;color:#fff;font-size:14px;font-weight:800;}
.otm-nav{display:flex;align-items:center;gap:4px;margin-left:auto;}
.otm-nav-item{position:relative;}
.otm-nav-item>a{display:block;padding:10px 14px;border-radius:8px;color:var(--ink-2);font-weight:600;font-size:14.5px;}
.otm-nav-item>a:hover{background:var(--surface-2);color:var(--primary);}
.otm-nav-sub{position:absolute;top:100%;left:0;min-width:200px;background:var(--surface);
  border:1px solid var(--line);border-radius:10px;box-shadow:var(--shadow);padding:6px;
  display:none;}
.otm-nav-item:hover .otm-nav-sub,.otm-nav-item:focus-within .otm-nav-sub{display:block;}
.otm-nav-sub a{display:block;padding:8px 12px;border-radius:7px;font-size:13.5px;color:var(--ink-2);}
.otm-nav-sub a:hover{background:var(--surface-2);color:var(--primary);}
.otm-hamburger{display:none;margin-left:auto;width:42px;height:42px;border:none;background:transparent;
  cursor:pointer;border-radius:8px;font-size:22px;color:var(--ink);}
.otm-hamburger:hover{background:var(--surface-2);}
.otm-mobile-nav{display:none;}

/* ===== 容器 / 面包屑 ===== */
.otm-wrap{max-width:var(--maxw);margin:0 auto;padding:0 20px;}
.otm-breadcrumb{border-left:3px solid transparent;padding-left:0;margin:18px 0 6px;font-size:13.5px;color:var(--ink-3);}
.otm-breadcrumb ol{list-style:none;display:flex;flex-wrap:wrap;gap:6px;margin:0;padding:0;}
.otm-breadcrumb li:not(:last-child)::after{content:"›";margin-left:6px;color:var(--line-strong);}
.otm-breadcrumb a{color:var(--ink-3);}
.otm-breadcrumb a:hover{color:var(--primary);}
.otm-article-layout>.otm-breadcrumb,.otm-list-layout>.otm-breadcrumb,.otm-product-layout>.otm-breadcrumb{grid-column:1/-1;}
.otm-cat-content{padding-left:0;}

/* ===== 详情页布局（内容 + TOC） ===== */
.otm-article-layout,.otm-product-layout{max-width:var(--maxw);margin:0 auto;padding:0 20px 50px;
  display:grid;grid-template-columns:minmax(0,1fr) 240px;gap:34px;align-items:start;}
.otm-content-main{padding-left:0;min-width:0;}
.otm-content-main .otm-summary{background:var(--surface);border:1px solid var(--line);border-left:4px solid var(--primary-2);
  border-radius:10px;padding:16px 18px;margin:0 0 18px;color:var(--ink-2);font-size:15px;}
.otm-content-main .otm-keywords{margin:0 0 16px;font-size:13.5px;color:var(--ink-3);}
.otm-content-main .otm-update{font-size:13px;color:var(--ink-3);margin:0 0 18px;}
.otm-content-main h2{padding-left:0;}
.otm-content-main>p,.otm-content-main>ul,.otm-content-main>ol,.otm-content-main>blockquote,.otm-content-main>table{
  max-width:820px;}

/* ===== 目录悬浮 ===== */
.otm-toc-aside{position:sticky;top:calc(var(--header-h) + 16px);max-height:calc(100vh - var(--header-h) - 40px);
  overflow:auto;}
.otm-toc-panel{background:var(--surface);border:1px solid var(--line);border-radius:12px;padding:12px 14px;box-shadow:var(--shadow-sm);}
.otm-toc-panel summary{cursor:pointer;font-weight:700;color:var(--ink);list-style:none;padding:4px 0;font-size:14.5px;}
.otm-toc-panel summary::after{content:"▾";float:right;color:var(--ink-3);}
.otm-toc-panel[open] summary::after{content:"▴";}
.otm-toc-panel ol{list-style:none;margin:8px 0 0;padding:0;counter-reset:toc;}
.otm-toc-panel li{counter-increment:toc;margin:2px 0;}
.otm-toc-panel li a{display:block;padding:5px 8px;border-radius:6px;color:var(--ink-2);font-size:13px;line-height:1.5;}
.otm-toc-panel li a:hover{background:var(--surface-2);color:var(--primary);}
.otm-toc-panel li a::before{content:counter(toc) ". ";color:var(--primary-2);font-weight:700;}

/* ===== 列表/分类页（侧栏 + 内容） ===== */
.otm-list-layout{max-width:var(--maxw);margin:0 auto;padding:0 20px 50px;
  display:grid;grid-template-columns:240px minmax(0,1fr);gap:30px;align-items:start;}
.otm-cat-side{position:sticky;top:calc(var(--header-h) + 16px);}
.otm-cat-panel{background:var(--surface);border:1px solid var(--line);border-radius:12px;padding:10px 12px;box-shadow:var(--shadow-sm);}
.otm-cat-panel summary{cursor:pointer;font-weight:700;list-style:none;padding:6px 0;font-size:15px;color:var(--ink);}
.otm-cat-panel summary::after{content:"▾";float:right;color:var(--ink-3);}
.otm-cat-panel[open] summary::after{content:"▴";}
.otm-cat-panel ul.category-list{list-style:none;margin:8px 0 0;padding:0;}
.otm-cat-panel ul.category-list li{margin:2px 0;}
.otm-cat-panel ul.category-list a{display:block;padding:7px 10px;border-radius:7px;color:var(--ink-2);font-size:13.5px;}
.otm-cat-panel ul.category-list a:hover,.otm-cat-panel ul.category-list a.active{background:var(--surface-2);color:var(--primary);font-weight:600;}
.otm-cat-content{min-width:0;}
.otm-cat-content .otm-cat-intro{background:var(--surface);border:1px solid var(--line);border-radius:12px;padding:18px 20px;margin-bottom:20px;color:var(--ink-2);}
.otm-list-grid{display:grid;grid-template-columns:repeat(auto-fill,minmax(240px,1fr));gap:18px;}

/* ===== 卡片 ===== */
.otm-card{background:var(--surface);border:1px solid var(--line);border-radius:var(--radius);padding:18px;
  box-shadow:var(--shadow-sm);transition:transform .15s,box-shadow .15s,border-color .15s;display:flex;flex-direction:column;}
.otm-card:hover{transform:translateY(-3px);box-shadow:var(--shadow);border-color:var(--primary-2);}
.otm-card h3{margin:0 0 8px;font-size:16.5px;}
.otm-card h3 a{color:var(--ink);}
.otm-card .otm-card-cat{font-size:12px;color:var(--primary);font-weight:700;letter-spacing:.3px;}
.otm-card p{font-size:13.5px;color:var(--ink-2);margin:6px 0 0;flex:1;}
.otm-card .otm-card-meta{margin-top:12px;font-size:12.5px;color:var(--ink-3);}

/* ===== 表格（M26 覆盖全部正文 table） ===== */
.otm-content-main table,.otm-page-main table,table.otm-spec{
  border-collapse:collapse;width:100%;max-width:820px;margin:16px 0;background:var(--surface);
  border:1px solid var(--line-strong);border-radius:10px;overflow:hidden;font-size:14px;}
.otm-content-main table th,.otm-page-main table th,table.otm-spec th{
  background:var(--primary);color:#fff;text-align:left;padding:9px 12px;font-weight:600;}
.otm-content-main table td,.otm-page-main table td,table.otm-spec td{
  padding:8px 12px;border-top:1px solid var(--line);color:var(--ink-2);}
.otm-content-main table tr:nth-child(even) td,.otm-page-main table tr:nth-child(even) td,table.otm-spec tr:nth-child(even) td{
  background:var(--surface-2);}

/* ===== 引用 / 列表 ===== */
.otm-content-main blockquote,.otm-page-main blockquote{
  border-left:4px solid var(--primary-2);background:var(--surface-2);margin:14px 0;padding:12px 16px;border-radius:8px;color:var(--ink-2);}
.otm-content-main ul,.otm-content-main ol,.otm-page-main ul,.otm-page-main ol{padding-left:22px;color:var(--ink-2);}
.otm-content-main li,.otm-page-main li{margin:6px 0;}

/* ===== 标签 / 结论 / 案例 / 相关 ===== */
.tag-text{display:inline-block;background:var(--surface-2);color:var(--primary);border:1px solid var(--line);
  border-radius:999px;padding:2px 10px;font-size:12.5px;margin:0 6px 6px 0;}
.otm-conclusion{background:var(--surface);border:1px solid var(--line);border-radius:12px;padding:16px 20px;margin:20px 0;}
.otm-conclusion h2{border:none;padding:0;margin:0 0 10px;font-size:18px;}
.otm-conclusion ol{margin:0;padding-left:22px;}
.otm-conclusion li{margin:8px 0;color:var(--ink-2);}
.otm-case{background:linear-gradient(135deg,#EAF6FB,#EAFBF4);border:1px solid #CDE9EF;border-radius:12px;
  padding:14px 18px;margin:20px 0;color:#0d4a5a;font-size:14.5px;}
.otm-case strong{color:var(--primary);}
.otm-related{margin:24px 0;padding:16px 20px;background:var(--surface);border:1px solid var(--line);border-radius:12px;}
.otm-related h2{border:none;padding:0;margin:0 0 10px;font-size:18px;}
.otm-related ul{list-style:none;padding:0;margin:0;}
.otm-related li{margin:8px 0;font-size:14px;color:var(--ink-2);}

/* ===== FAQ 裸 details ===== */
.otm-faq{margin:22px 0;}
.otm-faq details{border:1px solid var(--line);border-radius:10px;background:var(--surface);margin:8px 0;overflow:hidden;}
.otm-faq details summary{cursor:pointer;padding:12px 16px;font-weight:600;color:var(--ink);list-style:none;position:relative;padding-right:36px;}
.otm-faq details summary::after{content:"+";position:absolute;right:14px;top:50%;transform:translateY(-50%);font-size:20px;color:var(--primary);}
.otm-faq details[open] summary::after{content:"−";}
.otm-faq details div{padding:0 16px 14px;color:var(--ink-2);font-size:14.5px;}

/* ===== 页面（about/contact/...） ===== */
.otm-page-main{max-width:860px;margin:0 auto;padding:10px 20px 50px;}
.otm-page-main .otm-page-card{background:var(--surface);border:1px solid var(--line);border-radius:var(--radius);
  padding:26px 30px;box-shadow:var(--shadow-sm);padding-left:var(--h2-inset-page);}
.otm-page-card h2{padding-left:0;}
.otm-breadcrumb.otm-breadcrumb-page{padding-left:0;}

/* ===== 首页 hero / 区块 ===== */
.otm-hero{background:var(--primary-grad);color:#fff;border-radius:0 0 26px 26px;padding:56px 20px 60px;margin-bottom:34px;}
.otm-hero .otm-wrap{color:#fff;}
.otm-hero h1{color:#fff;font-size:34px;margin:0 0 14px;}
.otm-hero p{color:rgba(255,255,255,.92);font-size:17px;max-width:760px;}
.otm-hero .otm-hero-cta{margin-top:22px;display:flex;gap:14px;flex-wrap:wrap;}
.otm-btn{display:inline-block;padding:11px 22px;border-radius:10px;font-weight:700;font-size:14.5px;}
.otm-btn-primary{background:#fff;color:var(--primary);}
.otm-btn-ghost{background:rgba(255,255,255,.16);color:#fff;border:1px solid rgba(255,255,255,.5);}
.otm-stats{display:grid;grid-template-columns:repeat(auto-fit,minmax(150px,1fr));gap:16px;margin:30px 0;}
.otm-stat{background:var(--surface);border:1px solid var(--line);border-radius:12px;padding:18px;text-align:center;box-shadow:var(--shadow-sm);}
.otm-stat b{display:block;font-size:26px;color:var(--primary);}
.otm-stat span{font-size:13px;color:var(--ink-3);}
.otm-section{max-width:var(--maxw);margin:0 auto 40px;padding:0 20px;}
.otm-section h2{border-left:3px solid var(--primary);padding:0;margin:0 0 18px;font-size:24px;}
.otm-section h2::after{content:"";display:block;width:46px;height:3px;background:var(--primary-grad);margin-top:8px;border-radius:2px;}
.otm-pill{display:inline-block;background:var(--surface-2);border:1px solid var(--line);border-radius:999px;
  padding:6px 14px;margin:0 8px 8px 0;font-size:13.5px;color:var(--ink-2);}
.otm-baseline{background:var(--surface);border:1px solid var(--line);border-left:4px solid var(--primary);border-radius:12px;padding:20px 24px;color:var(--ink-2);}
.otm-baseline ul{margin:10px 0 0;padding-left:22px;}
.otm-baseline li{margin:6px 0;}

/* ===== 悬浮胶囊 ===== */
.otm-float{position:fixed;right:18px;top:50%;transform:translateY(-50%);z-index:60;display:flex;flex-direction:column;gap:10px;}
.otm-float button{width:auto;min-width:46px;height:46px;border:none;cursor:pointer;border-radius:999px;
  background:var(--primary-grad);color:#fff;font-size:13px;font-weight:600;padding:0 14px;
  box-shadow:var(--shadow);display:flex;align-items:center;gap:6px;justify-content:center;white-space:nowrap;}
.otm-float button:hover{filter:brightness(1.06);}
.otm-modal-mask{position:fixed;inset:0;background:rgba(10,20,35,.55);z-index:90;display:none;align-items:center;justify-content:center;padding:20px;}
.otm-modal-mask.open{display:flex;}
.otm-modal{background:#fff;border-radius:14px;padding:16px;max-width:92vw;max-height:92vh;overflow:auto;text-align:center;box-shadow:var(--shadow);}
.otm-modal img{max-width:240px;width:100%;height:auto;max-height:62vh;object-fit:contain;}
.otm-modal .otm-modal-close{margin-top:12px;}

/* ===== 页脚 ===== */
.otm-footer{background:#0C1A2E;color:#B9C6D6;margin-top:50px;padding:40px 20px 26px;}
.otm-footer .otm-wrap{display:grid;grid-template-columns:1.4fr 1fr 1fr;gap:30px;}
.otm-footer h4{color:#fff;font-size:15px;margin:0 0 12px;}
.otm-footer a{color:#B9C6D6;}
.otm-footer a:hover{color:#fff;}
.otm-footer ul{list-style:none;padding:0;margin:0;}
.otm-footer li{margin:7px 0;font-size:13.5px;}
.otm-footer .otm-foot-bottom{border-top:1px solid #1d2c42;margin-top:26px;padding-top:18px;text-align:center;font-size:13px;color:#7E8CA0;}

/* ===== 响应式（断点 1024 与 responsive_folding 一致） ===== */
@media (max-width:1024px){
  .otm-nav{display:none;}
  .otm-hamburger{display:block;}
  .otm-mobile-nav.open{display:block;position:absolute;top:var(--header-h);left:0;right:0;background:#fff;
    border-bottom:1px solid var(--line);box-shadow:var(--shadow);padding:10px 20px;}
  .otm-mobile-nav a{display:block;padding:10px 0;color:var(--ink-2);font-weight:600;border-bottom:1px solid var(--line);}
  .otm-mobile-nav details{padding:6px 0;}
  .otm-mobile-nav summary{font-weight:700;color:var(--ink);cursor:pointer;}
  .otm-mobile-nav .otm-mobile-sub a{padding-left:14px;font-weight:500;font-size:14px;}
  .otm-article-layout,.otm-product-layout{grid-template-columns:1fr;}
  .otm-toc-aside{position:static;max-height:none;}
  .otm-list-layout{grid-template-columns:1fr;}
  .otm-cat-side{position:static;}
  .otm-content-main{padding-left:0;}
  .otm-breadcrumb{padding-left:0;}
  .otm-page-main .otm-page-card{padding-left:20px;}
  .otm-breadcrumb.otm-breadcrumb-page{padding-left:0;}
}
@media (max-width:600px){
  .otm-hero h1{font-size:26px;}
  .otm-footer .otm-wrap{grid-template-columns:1fr;}
  .otm-float{right:10px;}
}