:root { --bg:#f3f7fa; --bg-alt:#fff; --text:#152b3e; --muted:#6d8091; --primary:#168dbe; --primary-soft:#eaf6fc; --primary-strong:#116a91; --border:#e2eaf0; --shadow-md:none; --shadow-lg:none; --shadow-sm:none; --max-width:1360px; }
:root[data-theme=dark] { --bg:#0a1521; --bg-alt:#101f2e; --text:#e6f0f7; --muted:#95aabb; --primary:#51bde9; --primary-soft:#15354b; --primary-strong:#87d7f5; --border:#233747; }
html { scroll-behavior:smooth; scroll-padding-top:100px; }
body.classic-theme { background:var(--bg); color:var(--text); font-family:Inter,-apple-system,BlinkMacSystemFont,"Segoe UI","Microsoft YaHei",sans-serif; line-height:1.7; }
* { box-sizing:border-box; }
a { text-underline-offset:4px; }
button,input { font:inherit; }
:focus-visible { outline:3px solid #30a9dc; outline-offset:4px; }
.site-header { background:var(--bg-alt); box-shadow:none; border-bottom:1px solid var(--border); position:sticky; top:0; z-index:50; padding:0; }
.site-header-box { max-width:1360px; width:calc(100% - 64px); min-height:84px; padding:12px 0; margin:auto; display:flex; justify-content:space-between; gap:24px; }
.brand-title { font-size:19px; letter-spacing:-.6px; font-weight:750; display:flex; gap:12px; align-items:center; color:var(--text); }
.brand-logo { width:44px; height:44px; border-radius:12px; box-shadow:none; }
.flight-brand { display:flex; flex-direction:column; line-height:1.4; }
.flight-brand small { font-size:10px; letter-spacing:2px; font-weight:500; color:var(--muted); margin-top:3px; }
.site-nav-box { gap:24px; }
.site-nav { gap:22px; }
.site-nav .nav-link { background:none; padding:10px 0; border-radius:0; font-size:13px; font-weight:500; color:var(--muted); }
.site-nav .nav-link:hover,.site-nav .nav-link[aria-current=page] { color:var(--primary); box-shadow:inset 0 -2px var(--primary); }
.theme-switch { transform:scale(.82); margin:0; }
.switch-track { box-shadow:none; }
.site-main,.site-main:has(.help-grid) { width:calc(100% - 64px); max-width:1360px; padding:32px 0 64px; margin:0 auto; }
.flight-hero { position:relative; isolation:isolate; overflow:hidden; color:#fff; background:#102d46; border-radius:8px; padding:52px 54px; margin-bottom:38px; min-height:310px; display:flex; align-items:center; }
.flight-hero:before { content:""; position:absolute; inset:0; z-index:-1; background:radial-gradient(ellipse at 92% 40%,#19618a88,transparent 60%); }
.flight-eyebrow { color:#7fd5f5; font-size:10px; font-weight:600; letter-spacing:3px; margin:0 0 18px; display:flex; align-items:center; gap:10px; }
.flight-eyebrow:before { content:""; width:24px; height:1px; background:#63c6ee; }
.flight-hero h1 { font-size:clamp(32px,3.2vw,46px); line-height:1.3; letter-spacing:-1.5px; margin:0 0 16px; color:#fff; font-weight:650; }
.flight-hero h1 span { color:#54bde9; }
.flight-hero p.flight-intro { color:#aec4d5; font-size:13px; max-width:530px; line-height:1.9; margin:0; }
.flight-hero-actions { display:flex; align-items:center; gap:26px; margin-top:26px; }
.flight-hero-actions a { font-size:12px; text-decoration:none; color:#e5f6ff; }
.flight-hero-actions a:first-child { color:#102d46; background:#7fd5f5; padding:10px 18px; border-radius:4px; font-weight:650; }
.flight-art { position:absolute; right:7%; width:255px; height:255px; border:1px solid #84cfff21; border-radius:50%; display:grid; place-items:center; transform:rotate(-12deg); pointer-events:none; }
.flight-art:before,.flight-art:after { content:""; position:absolute; border:1px solid #84cfff21; border-radius:50%; width:72%; height:72%; }
.flight-art:after { width:135%; height:135%; border-style:dashed; }
.flight-art svg { width:115px; height:115px; filter:drop-shadow(0 16px 18px #00172555); }
.flight-coordinate { position:absolute; bottom:28px; right:35px; color:#80a5bc; font-size:9px; letter-spacing:2px; }
.site-main .grid-layout.help-grid { grid-template-columns:242px minmax(0,1fr); gap:34px; }
.site-main .help-grid.help-has-toc { grid-template-columns:242px minmax(0,1fr) 206px; gap:30px; }
body:not(.layout-post) .site-main .help-grid { grid-template-columns:242px minmax(0,1fr); }
body:not(.layout-post) .help-grid > .sidebar { display:none; }
.help-recommendations { top:108px; max-height:calc(100dvh - 128px); }
.help-recommendations .help-card { border-radius:6px; border:1px solid var(--border); box-shadow:none; padding:23px 12px 16px; background:var(--bg-alt); }
.help-eyebrow { color:var(--primary); font-size:9px; letter-spacing:2px; }
.help-card h2 { font-size:17px; margin-top:7px; margin-bottom:17px; font-weight:650; }
.help-card .help-link { grid-template-columns:14px 32px minmax(0,1fr) 12px; padding:14px 6px; gap:9px; border-radius:4px; border-bottom:1px solid var(--border); }
.help-card li:last-child .help-link { border-bottom:none; }
.help-logo { width:32px; height:32px; border-radius:7px; }
.help-name { font-size:13px; font-weight:650; }
.help-name small { font-size:10px; }
.help-rank,.help-card li:first-child .help-rank { font-size:10px; color:var(--primary); }
.help-card .help-more { color:var(--primary); border-top:none; padding:12px 0 0; margin-top:8px; font-size:11px; }
.flight-sidebar-note { font-size:10px; line-height:1.8; color:var(--muted); padding:16px 5px 0; margin:0; }
.flight-toolbar { display:flex; align-items:center; justify-content:space-between; gap:18px; margin-bottom:24px; border-bottom:1px solid var(--border); padding-bottom:19px; flex-wrap:wrap; }
.flight-section-title { margin:0; font-size:21px; letter-spacing:-.6px; font-weight:650; }
.flight-section-title small { font-size:10px; font-weight:400; color:var(--muted); margin-left:12px; letter-spacing:1px; }
.flight-search { border:1px solid var(--border); background:var(--bg-alt); color:var(--text); padding:9px 12px; border-radius:4px; width:230px; font-size:12px; }
.flight-filters { display:flex; gap:8px; margin-bottom:20px; }
.flight-filter { color:var(--muted); border:1px solid transparent; background:transparent; font-size:11px; cursor:pointer; padding:6px 12px; border-radius:4px; }
.flight-filter[aria-pressed=true] { background:var(--primary-soft); color:var(--primary); border-color:var(--border); }
.flight-results { display:grid; grid-template-columns:repeat(2,minmax(0,1fr)); gap:18px; }
.flight-results .summary-card { display:flex; flex-direction:column; min-width:0; background:var(--bg-alt); padding:24px; border-radius:6px; box-shadow:none; border:1px solid var(--border); margin:0; transition:border-color .2s,background .2s!important; transform:none!important; position:relative; }
.flight-results .summary-card:hover { border-color:#6cbdda; background:var(--bg-alt); }
.flight-results .summary-card h2 { font-size:17px; line-height:1.65; letter-spacing:-.3px; display:block; margin:12px 0; order:1; }
.flight-results .summary-card h2 a { color:var(--text); text-decoration:none; }
.flight-results .summary-meta { margin:0; gap:12px; order:0; font-size:10px; color:var(--muted); justify-content:space-between; }
.flight-results .summary-meta span { border:0; padding:0; background:transparent!important; color:var(--muted)!important; }
.flight-results .summary-meta a { color:var(--primary)!important; }
.flight-results .summary-divider { display:none; }
.flight-results .summary-desc { order:2; margin:0 0 20px; color:var(--muted); font-size:12px; line-height:1.9; display:-webkit-box; -webkit-line-clamp:3; -webkit-box-orient:vertical; overflow:hidden; }
.flight-read { order:3; margin-top:auto; color:var(--primary); font-size:11px; padding-top:16px; border-top:1px solid var(--border); text-decoration:none; display:flex; justify-content:space-between; }
.flight-empty { border:1px dashed var(--border); padding:45px 24px; color:var(--muted); text-align:center; font-size:14px; }
.flight-load { display:block; margin:26px auto 0; padding:10px 26px; background:var(--bg-alt); border:1px solid var(--border); color:var(--text); border-radius:4px; font-size:12px; cursor:pointer; }
.flight-results [hidden], .flight-load[hidden], .flight-empty[hidden] { display:none!important; }
.help-grid .post-list.post { overflow:visible; }
.help-grid .post-card { padding:36px 40px; background:var(--bg-alt); border:1px solid var(--border); border-radius:6px; box-shadow:none; }
.post-header { margin:0 0 30px; padding:0 0 26px; border-bottom:1px solid var(--border); text-align:left; }
.post-breadcrumb { margin:0 0 22px; color:var(--muted); font-size:10px; overflow-wrap:anywhere; }
.post-title { text-align:left; text-wrap:balance; font-size:clamp(25px,2.3vw,35px); line-height:1.5; font-weight:650; letter-spacing:-.9px; margin:0 0 18px; color:var(--text); }
.post-meta-other,.post-meta { text-align:left; justify-content:flex-start; font-size:11px; color:var(--muted); margin:10px 0 0; }
.chip,.tag-chip { border-radius:4px; box-shadow:none; background:var(--primary-soft); color:var(--primary); font-size:11px; }
.help-grid .post-content { font-size:15px; line-height:2; color:var(--text); }
.help-grid .post-content p { line-height:2; margin:1.3em 0; }
.help-grid .post-content :is(h2,h3,h4) { color:var(--text); line-height:1.6; margin-top:2em; overflow:visible; }
.help-grid .post-content h2 { font-size:25px; }
.help-grid .post-content h3 { font-size:21px; }
.help-grid .post-content blockquote { border-left:3px solid #32a9db; background:var(--primary-soft); color:var(--muted); padding:8px 20px; margin:24px 0; border-radius:0 4px 4px 0; }
.help-grid .post-content table { display:block; overflow-x:auto; max-width:100%; font-size:12px; border-collapse:collapse; }
.help-grid .post-content table th { background:var(--primary-soft); }
.help-grid .post-content :is(th,td) { border-color:var(--border); padding:10px 12px; }
.help-grid .post-content hr { height:1px; border:0; background:var(--border); margin:30px 0; }
.help-grid > .sidebar { top:108px; max-height:calc(100dvh - 130px); overflow-y:auto; scrollbar-width:thin; }
.help-grid > .sidebar .sidebar-card { padding:8px 0 16px 18px; border-radius:0; background:none; border-left:1px solid var(--border); box-shadow:none; }
.help-grid > .sidebar h2 { font-size:12px; margin-bottom:15px; padding-bottom:12px; color:var(--muted); font-weight:500; }
.help-grid > .sidebar .anchor-level a { font-size:11px; line-height:1.8; color:var(--muted); padding:7px 0; }
.help-grid > .sidebar .anchor-level a:hover { color:var(--primary); }
.site-footer { border-top:1px solid var(--border); padding:30px 32px; background:var(--bg-alt); color:var(--muted); font-size:11px; text-align:left; }
.flight-footer-inner { max-width:1360px; margin:auto; display:flex; justify-content:space-between; gap:15px; }
.flight-footer-inner strong { font-size:12px; color:var(--text); font-weight:500; }
.mobile-menu-button { background:transparent; box-shadow:none; border:1px solid var(--border); border-radius:6px; color:var(--text); width:36px; height:36px; }
.mobile-drawer { background:var(--bg-alt); color:var(--text); }
@media(min-width:981px) and (max-width:1279px) { .site-main .help-grid.help-has-toc { grid-template-columns:220px minmax(0,1fr);gap:24px; } .site-main .grid-layout.help-grid { grid-template-columns:220px minmax(0,1fr);gap:24px; } .flight-art { right:2%; opacity:.55; } .flight-hero>div:first-child { z-index:1; } .flight-results { gap:14px; } .flight-results .summary-card { padding:20px; } }
@media(max-width:980px) { .site-main,.site-main:has(.help-grid) { width:calc(100% - 40px);max-width:none;padding-top:24px; } .site-main .grid-layout.help-grid,.site-main .help-grid.help-has-toc,body:not(.layout-post) .site-main .help-grid { grid-template-columns:minmax(0,1fr); } .flight-hero { padding:38px; } .flight-art { right:-65px;opacity:.25; } .site-header-box { width:calc(100% - 40px); } .help-recommendations {display:none;} }
@media(max-width:600px) { .site-header-box { min-height:70px;width:calc(100% - 32px);gap:12px; } .brand-title { font-size:16px;gap:9px; } .brand-logo {width:36px;height:36px;border-radius:9px;} .flight-brand small {font-size:8px;} .site-main,.site-main:has(.help-grid) {width:calc(100% - 28px);padding:18px 0 38px;} .flight-hero {padding:30px 24px;min-height:290px;margin-bottom:28px;} .flight-hero h1 {font-size:31px;letter-spacing:-1px;} .flight-hero p.flight-intro {font-size:12px;max-width:280px;} .flight-art {right:-105px;opacity:.15;} .flight-coordinate {display:none;} .flight-hero-actions {gap:20px;} .flight-toolbar {gap:14px;margin-bottom:14px;padding-bottom:17px;} .flight-search {width:100%;} .flight-section-title {font-size:20px;} .flight-results {grid-template-columns:1fr;gap:12px;} .flight-results .summary-card {padding:22px;} .flight-results .summary-card h2 {font-size:17px;} .help-grid .post-card {padding:26px 22px;} .post-title {font-size:25px;letter-spacing:-.5px;} .help-grid .post-content {font-size:14px;} .help-grid .post-content h3 {font-size:20px;} .flight-footer-inner {flex-direction:column;gap:6px;} .site-footer {padding:24px;} }
@media(prefers-reduced-motion:reduce) { html {scroll-behavior:auto;} *,*:before,*:after {transition:none!important;animation:none!important;} }
/* Quiet, compact scrollbars for the recommendation list and article outline. */
.help-recommendations,.help-grid > .sidebar {
  --rail-thumb:#c1d4df;
  scrollbar-width:thin;
  scrollbar-color:var(--rail-thumb) transparent;
  padding-right:4px;
}
.help-recommendations:hover,.help-recommendations:focus-within,
.help-grid > .sidebar:hover,.help-grid > .sidebar:focus-within { --rail-thumb:#77acc5; }
:root[data-theme=dark] .help-recommendations,
:root[data-theme=dark] .help-grid > .sidebar { --rail-thumb:#29485b; }
:root[data-theme=dark] .help-recommendations:hover,
:root[data-theme=dark] .help-recommendations:focus-within,
:root[data-theme=dark] .help-grid > .sidebar:hover,
:root[data-theme=dark] .help-grid > .sidebar:focus-within { --rail-thumb:#5089a6; }
@supports selector(::-webkit-scrollbar) {
  .help-recommendations,.help-grid > .sidebar { scrollbar-width:auto; scrollbar-color:auto; }
  .help-recommendations::-webkit-scrollbar,.help-grid > .sidebar::-webkit-scrollbar { width:6px; height:6px; }
  .help-recommendations::-webkit-scrollbar-track,.help-grid > .sidebar::-webkit-scrollbar-track { background:transparent; }
  .help-recommendations::-webkit-scrollbar-thumb,.help-grid > .sidebar::-webkit-scrollbar-thumb { background:var(--rail-thumb); border-radius:10px; border:1px solid var(--bg); }
  .help-recommendations::-webkit-scrollbar-button,.help-grid > .sidebar::-webkit-scrollbar-button { display:none; width:0; height:0; }
  .help-recommendations::-webkit-scrollbar-corner,.help-grid > .sidebar::-webkit-scrollbar-corner { background:transparent; }
}