:root{
  --blue:#3454F5;
  --yellow:#FFD447;
  --paper:#F7F5EF;
  --ink:#171B26;
  --muted:#687083;
  --line:#DDE1EA;
  --white:#FFFFFF;
}
*{box-sizing:border-box}
html{scroll-behavior:smooth}
body{
  margin:0;
  font-family:Inter, ui-sans-serif, system-ui, -apple-system, BlinkMacSystemFont, "Segoe UI", sans-serif;
  background:var(--paper);
  color:var(--ink);
  line-height:1.55;
}
a{color:inherit;text-decoration:none}
img{max-width:100%}
.container{width:min(1160px,calc(100% - 32px));margin:0 auto}
.topbar{
  position:sticky;top:0;z-index:10;
  background:rgba(247,245,239,.94);
  backdrop-filter:blur(12px);
  border-bottom:1px solid rgba(23,27,38,.08);
}
.nav{height:72px;display:flex;align-items:center;justify-content:space-between;gap:24px}
.brand{display:flex;align-items:center;gap:12px;font-weight:900;letter-spacing:-.04em;font-size:24px}
.stamp{
  display:inline-flex;align-items:center;justify-content:center;
  width:42px;height:42px;background:var(--yellow);border:2px solid var(--ink);
  transform:rotate(-5deg);font-size:16px;font-weight:900;
}
.navlinks{display:flex;align-items:center;gap:24px;font-size:15px;font-weight:700}
.navcta{background:var(--ink);color:white;padding:11px 16px;border-radius:999px}
.hero{padding:72px 0 56px}
.hero-grid{display:grid;grid-template-columns:1.15fr .85fr;gap:44px;align-items:center}
.eyebrow{font-size:14px;font-weight:900;text-transform:uppercase;letter-spacing:.12em;color:var(--blue)}
h1{font-size:clamp(52px,7vw,92px);line-height:.92;letter-spacing:-.065em;margin:14px 0 20px}
h1 .xl{display:inline-block;background:var(--yellow);padding:0 .12em;border:3px solid var(--ink);transform:rotate(-3deg)}
.lead{font-size:clamp(19px,2vw,25px);max-width:720px;color:#343a49;margin:0 0 28px}
.actions{display:flex;gap:12px;flex-wrap:wrap}
.btn{display:inline-flex;align-items:center;justify-content:center;padding:14px 20px;border-radius:14px;border:2px solid var(--ink);font-weight:900}
.btn-primary{background:var(--blue);color:white;border-color:var(--blue)}
.btn-secondary{background:transparent}
.micro{margin-top:18px;color:var(--muted);font-size:14px}
.hero-panel{
  background:var(--ink);color:white;border-radius:28px;padding:28px;min-height:420px;
  display:flex;flex-direction:column;justify-content:space-between;
  box-shadow:0 24px 60px rgba(23,27,38,.15)
}
.hero-panel .rmark{font-size:60px;font-weight:900;letter-spacing:-.08em;color:var(--yellow)}
.hero-panel h2{font-size:36px;line-height:1.02;letter-spacing:-.04em;margin:8px 0 14px}
.hero-panel p{color:#D6DAE4}
.statrow{display:grid;grid-template-columns:repeat(3,1fr);gap:10px}
.stat{border:1px solid rgba(255,255,255,.15);padding:14px;border-radius:16px}
.stat strong{display:block;font-size:24px;color:var(--yellow)}
.section{padding:64px 0}
.section.dark{background:var(--ink);color:white}
.section h2{font-size:clamp(36px,5vw,60px);line-height:1;letter-spacing:-.05em;margin:0 0 18px}
.section-intro{font-size:19px;color:var(--muted);max-width:760px}
.dark .section-intro{color:#BEC4D0}
.grid3{display:grid;grid-template-columns:repeat(3,1fr);gap:18px;margin-top:28px}
.card{
  background:white;border:1px solid var(--line);border-radius:22px;padding:22px;
  min-height:220px;display:flex;flex-direction:column;justify-content:space-between
}
.card .num{font-size:54px;line-height:1;font-weight:900;color:var(--blue);letter-spacing:-.06em}
.card h3{font-size:24px;margin:18px 0 8px;letter-spacing:-.03em}
.card p{margin:0;color:var(--muted)}
.subjects{display:grid;grid-template-columns:repeat(2,1fr);gap:18px;margin-top:28px}
.subject{
  background:var(--paper);border:2px solid var(--ink);padding:24px;border-radius:20px;
  transition:.15s transform ease,.15s box-shadow ease
}
.subject:hover{transform:translateY(-3px);box-shadow:8px 8px 0 var(--yellow)}
.subject small{font-weight:900;color:var(--blue);text-transform:uppercase;letter-spacing:.1em}
.subject h3{font-size:30px;margin:8px 0 6px;letter-spacing:-.04em}
.topic-list{display:grid;grid-template-columns:repeat(2,1fr);gap:12px;margin-top:22px}
.topic{
  background:white;border:1px solid var(--line);padding:16px 18px;border-radius:14px;font-weight:800;
  display:flex;justify-content:space-between;align-items:center
}
.topic span:last-child{color:var(--blue)}
.band{background:var(--blue);color:white;padding:52px 0}
.band-inner{display:flex;align-items:center;justify-content:space-between;gap:24px}
.band h2{margin:0;font-size:clamp(32px,4vw,50px);letter-spacing:-.04em}
.band p{margin:8px 0 0;color:#DCE2FF}
.footer{padding:36px 0 48px;border-top:1px solid rgba(23,27,38,.1);font-size:14px;color:var(--muted)}
.footer-inner{display:flex;justify-content:space-between;gap:20px;flex-wrap:wrap}
.breadcrumb{padding:24px 0 0;font-size:14px;color:var(--muted)}
.article{padding:34px 0 72px}
.article-wrap{display:grid;grid-template-columns:minmax(0,1fr) 300px;gap:36px}
.article h1{font-size:clamp(44px,6vw,72px);margin-top:8px}
.article h2{font-size:32px;letter-spacing:-.035em;margin-top:42px}
.article p{font-size:18px}
.article .intro{font-size:22px;color:#3A4150}
.remember{background:white;border-left:6px solid var(--yellow);padding:22px 24px;border-radius:18px;margin:28px 0}
.remember ol{padding-left:22px}
.quiz{display:grid;gap:12px;margin-top:18px}
.qitem{background:white;border:1px solid var(--line);padding:16px 18px;border-radius:14px}
.sidebox{position:sticky;top:96px;background:var(--ink);color:white;padding:20px;border-radius:18px;height:max-content}
.sidebox .rmark{color:var(--yellow);font-weight:900;font-size:30px}
.sidebox p{color:#D6DAE4}
.sidebox .btn{width:100%;background:var(--yellow);color:var(--ink);border-color:var(--yellow)}
.powered{font-size:13px;color:var(--muted);margin-top:8px}
.searchbox{margin-top:26px;display:flex;gap:10px}
.searchbox input{flex:1;padding:14px 16px;border:2px solid var(--ink);border-radius:14px;background:white;font-size:16px}
.searchbox button{padding:14px 18px;border:0;border-radius:14px;background:var(--ink);color:white;font-weight:900}
@media (max-width:900px){
  .hero-grid,.article-wrap{grid-template-columns:1fr}
  .hero-panel{min-height:360px}
  .grid3{grid-template-columns:1fr}
  .subjects,.topic-list{grid-template-columns:1fr}
  .navlinks a:not(.navcta){display:none}
  .band-inner{align-items:flex-start;flex-direction:column}
  .sidebox{position:static}
}
@media (max-width:560px){
  .container{width:min(100% - 22px,1160px)}
  .hero{padding-top:48px}
  h1{font-size:52px}
  .statrow{grid-template-columns:1fr}
  .nav{height:64px}
  .brand{font-size:21px}
  .stamp{width:38px;height:38px}
}