*,*::before,*::after{box-sizing:border-box;margin:0;padding:0}
html{scroll-behavior:smooth}
:root{
  --teal:#0f766e;--teal-dark:#115e59;--teal-light:#ccfbf1;
  --jade:#14b8a6;--ink:#134e4a;--text:#1e293b;--muted:#64748b;
  --line:#99f6e4;--cream:#f0fdfa;--white:#fff;
  --grid-a:repeating-linear-gradient(0deg,transparent,transparent 11px,rgba(15,118,110,.05) 11px,rgba(15,118,110,.05) 22px);
  --grid-b:repeating-linear-gradient(90deg,transparent,transparent 11px,rgba(20,184,166,.06) 11px,rgba(20,184,166,.06) 22px)
}
body{font-family:"Noto Sans SC",system-ui,sans-serif;background:#fff;color:var(--text);line-height:1.78;font-size:16px}
a{color:var(--teal-dark);text-decoration:none}
a:hover{text-decoration:underline}
img{max-width:100%;height:auto;display:block}

.site-header{background:#fff;border-bottom:3px solid var(--teal);position:sticky;top:0;z-index:300}
.header-inner{max-width:1140px;margin:0 auto;padding:12px 20px;display:flex;align-items:center;justify-content:space-between;gap:16px;position:relative}
.brand{display:flex;align-items:center;gap:10px;color:#111;font-weight:600;font-size:.94rem}
.brand:hover{text-decoration:none}
.brand img{border-radius:8px;border:1px solid var(--line)}
.brand em{font-style:normal;color:var(--teal-dark);font-weight:700}
.site-nav ul{display:flex;flex-wrap:wrap;gap:6px 18px;list-style:none}
.site-nav a{color:var(--muted);font-size:.9rem;padding:4px 0}
.site-nav a.active,.site-nav a:hover{color:var(--teal-dark);font-weight:600;border-bottom:2px solid var(--jade);text-decoration:none}
.nav-toggle{display:none;background:none;border:none;cursor:pointer;padding:8px;flex-direction:column;gap:5px}
.nav-toggle span{display:block;width:22px;height:2px;background:#333;transition:.2s}
.nav-toggle.is-open span:nth-child(1){transform:translateY(7px) rotate(45deg)}
.nav-toggle.is-open span:nth-child(2){opacity:0}
.nav-toggle.is-open span:nth-child(3){transform:translateY(-7px) rotate(-45deg)}

.ads-top-bar{background:var(--cream);border-bottom:1px solid var(--line);padding:10px 0}
.applist-title{font-size:.78rem;color:var(--teal-dark);text-align:center;margin-bottom:6px}
#ads{display:flex;justify-content:center;flex-wrap:wrap;gap:12px}

.page-shell{max-width:1140px;margin:0 auto;padding:24px 20px 52px}

.chapter-nav{display:flex;flex-wrap:wrap;gap:8px 10px;padding:0 0 22px;margin-bottom:26px;border-bottom:2px solid var(--line)}
.chapter-nav a{font-size:.82rem;padding:7px 15px;border-radius:14px 4px 14px 4px;border:1.5px solid var(--line);color:var(--ink);background:var(--white);transition:all .15s}
.chapter-nav a:hover,.chapter-nav a.is-active{background:var(--teal-dark);color:#fff;border-color:var(--teal-dark);text-decoration:none;font-weight:600}

.checker-grid{
  display:grid;
  grid-template-columns:repeat(2,1fr);
  gap:4px;
  background:var(--teal);
  border:3px solid var(--teal-dark);
  border-radius:6px 24px 6px 24px;
  overflow:hidden;
  box-shadow:7px 7px 0 rgba(17,94,89,.12)
}
.checker-cell{
  padding:24px 22px;
  min-height:196px;
  background:var(--white);
  position:relative
}
.checker-cell:nth-child(4n+1){background-image:var(--grid-a)}
.checker-cell:nth-child(4n+2){background-image:var(--grid-b)}
.checker-cell:nth-child(4n+3){background-image:var(--grid-b)}
.checker-cell:nth-child(4n){background-image:var(--grid-a)}
.checker-cell--lead{
  grid-column:1/-1;
  background:linear-gradient(120deg,var(--teal-dark) 0%,var(--jade) 60%,#5eead4 100%);
  background-image:none;
  color:#fff;
  padding:34px 30px;
  border-bottom:3px solid rgba(255,255,255,.22)
}
.checker-cell--lead::before{
  content:"";
  position:absolute;inset:0;
  background:var(--grid-a);
  opacity:.12;
  pointer-events:none
}
.checker-cell--lead>*{position:relative;z-index:1}
.checker-cell--lead h1{font-size:clamp(1.32rem,3.4vw,1.9rem);line-height:1.35;margin-bottom:14px;color:#fff}
.checker-cell--lead .hero-badge{
  display:inline-block;font-size:.75rem;font-weight:700;
  color:var(--teal-dark);background:#fff;
  padding:5px 16px;border-radius:12px 4px 12px 4px;margin-bottom:14px;
  box-shadow:2px 2px 0 rgba(0,0,0,.07)
}
.checker-cell--lead p{color:#ecfeff;font-size:1rem;margin-bottom:10px;text-align:justify}
.checker-cell--lead p:last-child{margin-bottom:0}
.chip-row{display:flex;flex-wrap:wrap;gap:8px;margin-top:16px}
.chip-row span{font-size:.76rem;padding:5px 12px;border-radius:999px;background:rgba(255,255,255,.18);color:#fff;border:1px solid rgba(255,255,255,.32)}

.checker-cell h2{font-size:1.08rem;color:var(--teal-dark);margin-bottom:10px;line-height:1.36;padding-left:10px;border-left:4px solid var(--jade)}
.checker-cell p{margin-bottom:10px;text-align:justify;color:#334155;font-size:.95rem}
.checker-cell p:last-child{margin-bottom:0}
.checker-cell figure{margin:14px 0 0;border-radius:12px 4px 12px 4px;overflow:hidden;border:2px solid var(--line);background:#fff;box-shadow:3px 3px 0 var(--teal-light)}
.checker-cell figcaption{font-size:.79rem;color:var(--muted);padding:9px 13px;background:var(--cream)}

.note-box{
  background:var(--cream);
  border:1px dashed var(--jade);
  border-radius:10px;
  padding:12px 16px;
  margin:12px 0 0;
  font-size:.91rem;
  color:#0f766e
}

.faq-panel{margin-top:38px;padding-top:28px;border-top:3px solid var(--teal)}
.faq-panel>h2{font-size:1.14rem;margin-bottom:16px;color:var(--teal-dark)}
.faq-item{border:1.5px solid var(--line);margin-bottom:10px;background:#fff;border-radius:12px 4px 12px 4px;overflow:hidden}
.faq-item h3{padding:14px 18px;font-size:.96rem;font-weight:600;color:#134e4a;background:var(--cream);border-bottom:1px solid var(--line)}
.faq-item p{padding:14px 18px;color:#475569;font-size:.93rem}

.read-more{max-width:1140px;margin:0 auto;padding:0 20px 36px}
.read-more h2{font-size:1.02rem;margin-bottom:12px;color:var(--teal-dark)}
.read-more ul{list-style:none;display:flex;flex-wrap:wrap;gap:10px 18px}
.read-more a{font-size:.9rem}

.extra-pad{max-width:1140px;margin:0 auto;padding:0 20px 40px}
.extra-pad h2{font-size:1.02rem;margin-bottom:10px;color:var(--teal-dark)}
.extra-pad p{text-align:justify;color:#475569;font-size:.94rem}

.site-footer{background:var(--cream);border-top:3px solid var(--teal);padding:28px 20px;text-align:center;font-size:.88rem;color:var(--muted)}
.footer-links{display:flex;flex-wrap:wrap;justify-content:center;gap:8px 16px;margin-bottom:10px}
.footer-links a{color:#475569}
.footer-sub{font-size:.82rem;color:var(--teal-dark);margin-top:6px}

.prose-page{max-width:780px;margin:0 auto;padding:32px 20px 48px}
.prose-page h1{font-size:1.5rem;margin-bottom:16px;color:var(--teal-dark)}
.prose-page p{margin-bottom:12px;text-align:justify;color:#334155}

.error-page{max-width:560px;margin:80px auto;padding:20px;text-align:center}
.error-page h1{font-size:3rem;color:var(--teal-dark);margin-bottom:12px}

@media(max-width:820px){
.checker-grid{grid-template-columns:1fr;border-radius:14px 6px 14px 6px}
.checker-cell--lead{grid-column:1}
.nav-toggle{display:flex}
.site-nav{position:absolute;top:100%;left:0;right:0;background:#fff;border-bottom:1px solid var(--line);padding:12px 20px;display:none;box-shadow:0 6px 18px rgba(0,0,0,.07)}
.site-nav.is-open{display:block}
.site-nav ul{flex-direction:column;gap:10px}
.checker-cell--lead h1{font-size:1.26rem}
}