:root{
  --bg:#0f172a;
  --panel:#111827;
  --panel-2:#172033;
  --card:#ffffff;
  --text:#162033;
  --muted:#65738a;
  --line:#e7edf6;
  --brand:#ff9900;
  --brand-2:#ffb84d;
  --blue:#2563eb;
  --green:#16a34a;
  --red:#dc2626;
  --shadow:0 20px 60px rgba(15,23,42,.12);
  --radius:22px;
}
*{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;
  color:var(--text);
  background:linear-gradient(135deg,#f7faff 0%,#eef5ff 40%,#fff8ec 100%);
}
.sidebar{
  position:fixed;
  left:0; top:0; bottom:0;
  width:285px;
  background:linear-gradient(180deg,#0b1220,#111827 55%,#1f2937);
  color:white;
  padding:24px 18px;
  overflow-y:auto;
  z-index:20;
  box-shadow:10px 0 40px rgba(15,23,42,.22);
}
.brand{display:flex; gap:12px; align-items:center; margin-bottom:28px}
.logo{
  width:46px;height:46px;border-radius:14px;
  background:linear-gradient(135deg,var(--brand),#ffd18a);
  display:grid;place-items:center;color:#111827;font-weight:900
}
.brand small{display:block;color:#b7c2d6;margin-top:3px;font-size:12px}
.sidebar nav{display:grid;gap:6px}
.sidebar a{
  color:#d9e4f7;text-decoration:none;padding:11px 12px;border-radius:12px;
  font-size:14px;transition:.2s ease;border:1px solid transparent
}
.sidebar a:hover,.sidebar a.active{
  background:rgba(255,255,255,.09);
  border-color:rgba(255,255,255,.13);
  color:white;
}
.menu-toggle{
  display:none;position:fixed;top:14px;left:14px;z-index:30;
  border:0;background:#111827;color:white;border-radius:999px;padding:10px 14px;
  box-shadow:var(--shadow)
}
.content{margin-left:285px;padding:28px;max-width:1450px}
.hero{
  min-height:540px;
  display:grid;grid-template-columns:1.3fr .7fr;gap:28px;align-items:center;
  padding:56px;
  border-radius:34px;
  background:
    radial-gradient(circle at 15% 20%,rgba(255,153,0,.28),transparent 30%),
    radial-gradient(circle at 90% 10%,rgba(37,99,235,.18),transparent 28%),
    linear-gradient(135deg,#111827,#1f2937);
  color:white;box-shadow:var(--shadow);overflow:hidden;
}
.eyebrow{color:var(--brand);text-transform:uppercase;letter-spacing:.12em;font-weight:800;font-size:12px;margin:0 0 10px}
.hero h1{font-size:clamp(38px,6vw,72px);line-height:1;letter-spacing:-.05em;margin:0 0 20px}
.lead{font-size:19px;line-height:1.7;color:#d5e1f3;max-width:800px}
.hero-actions{display:flex;gap:12px;flex-wrap:wrap;margin-top:24px}
.btn{
  display:inline-flex;align-items:center;justify-content:center;gap:8px;
  border-radius:999px;padding:12px 18px;text-decoration:none;border:0;cursor:pointer;
  font-weight:800;transition:.2s ease;font-size:14px
}
.btn.primary{background:var(--brand);color:#111827}
.btn.ghost{background:#fff;color:#172033;border:1px solid var(--line)}
.btn:hover{transform:translateY(-2px);box-shadow:0 12px 30px rgba(0,0,0,.15)}
.exam-card{
  background:rgba(255,255,255,.1);backdrop-filter:blur(18px);
  border:1px solid rgba(255,255,255,.16);
  border-radius:28px;padding:26px;
}
.exam-card h2{margin-top:0}
.exam-card ul{padding-left:20px;line-height:1.9;color:#e9f1ff}
.cards-row{
  display:grid;grid-template-columns:repeat(5,1fr);gap:14px;margin:22px 0
}
.mini-card{
  background:white;border:1px solid var(--line);border-radius:20px;padding:20px;box-shadow:var(--shadow);
  display:grid;gap:6px
}
.mini-card strong{font-size:34px;color:#111827}
.mini-card span{font-size:13px;color:var(--muted);line-height:1.4}
.section{padding:42px 0;scroll-margin-top:22px}
.section-title{margin-bottom:22px}
.section-title h2{font-size:clamp(28px,4vw,46px);line-height:1.05;margin:0 0 10px;letter-spacing:-.04em}
.section-title p:not(.eyebrow){color:var(--muted);line-height:1.7;max-width:920px}
.two-col{display:grid;grid-template-columns:1fr 1fr;gap:18px}
.info-panel,.domain-card{
  background:white;border:1px solid var(--line);border-radius:var(--radius);padding:26px;box-shadow:var(--shadow)
}
.info-panel p{color:var(--muted);line-height:1.8}
.domain-card{margin-bottom:22px;scroll-margin-top:20px}
.domain-head{display:flex;justify-content:space-between;gap:16px;align-items:flex-start;margin-bottom:20px}
.domain-head h3{font-size:30px;letter-spacing:-.03em;margin:0}
.weight{background:#111827;color:white;padding:10px 14px;border-radius:999px;font-weight:900;white-space:nowrap}
.task-grid{display:grid;grid-template-columns:repeat(2,minmax(0,1fr));gap:18px}
.task-block{
  border:1px solid var(--line);background:#f8fbff;border-radius:18px;padding:20px
}
.task-block h4{margin:0 0 12px;font-size:17px}
.task-block ul{margin:0;padding-left:20px;color:#40506a;line-height:1.75}
.exam-note{
  margin-top:18px;border-left:5px solid var(--brand);background:#fff7e8;border-radius:16px;padding:18px;color:#4a3613
}
.exam-note ul{margin:8px 0 0;padding-left:20px;line-height:1.7}
.search,select{
  width:100%;border:1px solid var(--line);border-radius:14px;padding:13px 14px;font-size:15px;background:white
}
.table-wrap{overflow:auto;background:white;border:1px solid var(--line);border-radius:var(--radius);box-shadow:var(--shadow)}
table{width:100%;border-collapse:collapse;min-width:780px}
th,td{padding:15px 16px;border-bottom:1px solid var(--line);vertical-align:top;text-align:left}
th{background:#111827;color:white;position:sticky;top:0}
td{line-height:1.55;color:#40506a}
td strong{color:#111827}
.flash-grid{display:grid;grid-template-columns:repeat(auto-fill,minmax(220px,1fr));gap:16px}
.flashcard{height:160px;perspective:1000px;outline:none}
.flash-inner{position:relative;width:100%;height:100%;transition:transform .5s;transform-style:preserve-3d}
.flashcard:hover .flash-inner,.flashcard:focus .flash-inner{transform:rotateY(180deg)}
.flash-front,.flash-back{
  position:absolute;inset:0;backface-visibility:hidden;
  background:white;border:1px solid var(--line);border-radius:22px;box-shadow:var(--shadow);
  display:flex;flex-direction:column;justify-content:center;align-items:center;text-align:center;padding:18px
}
.flash-front strong{font-size:21px}
.flash-front span{margin-top:12px;color:var(--muted);font-size:12px}
.flash-back{transform:rotateY(180deg);background:#111827;color:white;line-height:1.6}
.question-toolbar{display:grid;grid-template-columns:1fr 220px auto;gap:12px;margin-bottom:20px}
.question-list{display:grid;gap:16px}
.question-card{background:white;border:1px solid var(--line);border-radius:22px;padding:22px;box-shadow:var(--shadow)}
.question-meta{display:flex;justify-content:space-between;align-items:center;gap:10px;color:var(--muted);font-size:13px;margin-bottom:12px}
.badge{background:#eef5ff;color:#1d4ed8;border-radius:999px;padding:6px 10px;font-weight:800}
.question-card h3{margin:0 0 16px;font-size:18px;line-height:1.5}
.option{
  width:100%;display:block;text-align:left;border:1px solid var(--line);background:#f8fbff;
  border-radius:14px;padding:12px 14px;margin:8px 0;cursor:pointer;transition:.15s ease
}
.option:hover{background:#edf5ff}
.option.correct{background:#ecfdf5;border-color:#86efac;color:#166534}
.option.wrong{background:#fef2f2;border-color:#fecaca;color:#991b1b}
.explanation{display:none;margin-top:14px;padding:15px;border-radius:16px;background:#f8fafc;border:1px solid var(--line);color:#40506a;line-height:1.6}
.explanation.show{display:block}
.plan{display:grid;gap:12px}
.plan-item{
  background:white;border:1px solid var(--line);border-radius:20px;padding:18px;display:flex;gap:16px;box-shadow:var(--shadow)
}
.plan-item span{
  flex:0 0 76px;height:42px;border-radius:999px;background:#111827;color:white;display:grid;place-items:center;font-weight:900
}
.plan-item strong{display:block;margin-bottom:5px}
.plan-item p{margin:0;color:var(--muted);line-height:1.55}
footer{padding:34px 0;color:var(--muted);text-align:center}
.top-btn{
  position:fixed;right:22px;bottom:22px;width:46px;height:46px;border-radius:999px;border:0;
  background:var(--brand);color:#111827;font-weight:900;box-shadow:var(--shadow);cursor:pointer;display:none
}
.top-btn.show{display:block}
mark{background:#fff0c2;border-radius:4px;padding:0 2px}

@media(max-width:1050px){
  .sidebar{transform:translateX(-105%);transition:.25s ease}
  .sidebar.open{transform:translateX(0)}
  .menu-toggle{display:block}
  .content{margin-left:0;padding:72px 18px 24px}
  .hero{grid-template-columns:1fr;padding:34px 24px}
  .cards-row{grid-template-columns:repeat(2,1fr)}
  .task-grid,.two-col{grid-template-columns:1fr}
  .question-toolbar{grid-template-columns:1fr}
}
@media(max-width:620px){
  .cards-row{grid-template-columns:1fr}
  .domain-head{flex-direction:column}
  .hero h1{font-size:42px}
}