:root{
  --bg:#07111f; --panel:#0e1b2f; --panel2:#13243d; --text:#f4f7fb; --muted:#9eb0c8;
  --line:#263a56; --accent:#66a7ff; --good:#3ddc97; --bad:#ff7070; --warn:#f2c86b;
  --shadow:0 12px 32px rgba(0,0,0,.24);
}
*{box-sizing:border-box;-webkit-tap-highlight-color:transparent}
html,body{margin:0;min-height:100%;background:var(--bg);color:var(--text);font-family:-apple-system,BlinkMacSystemFont,"Segoe UI",Roboto,Arial,sans-serif}
body{padding:max(12px,env(safe-area-inset-top)) max(14px,env(safe-area-inset-right)) max(18px,env(safe-area-inset-bottom)) max(14px,env(safe-area-inset-left))}
button,input,select{font:inherit}
button{touch-action:manipulation}
.app{max-width:920px;margin:0 auto}
.top{display:flex;align-items:center;justify-content:space-between;gap:12px;margin:4px 0 18px}
.brand{display:flex;align-items:center;gap:12px}
.logo{width:44px;height:44px;border-radius:13px;background:linear-gradient(145deg,#16365e,#0a1a2f);display:grid;place-items:center;border:1px solid var(--line);box-shadow:var(--shadow);font-weight:800}
.brand h1{font-size:20px;margin:0}.brand small{color:var(--muted)}
.iconbtn,.ghost,.primary,.danger,.choice,.rangebtn,.modebtn{border:0;border-radius:14px;cursor:pointer}
.iconbtn,.ghost{background:var(--panel);color:var(--text);border:1px solid var(--line);padding:11px 14px}
.primary{background:var(--accent);color:#06101c;font-weight:800;padding:13px 18px}
.danger{background:transparent;color:var(--bad);border:1px solid rgba(255,112,112,.45);padding:11px 14px}
.panel{background:var(--panel);border:1px solid var(--line);border-radius:20px;padding:18px;box-shadow:var(--shadow);margin-bottom:14px}
.hero{padding:24px}.hero h2{font-size:30px;line-height:1.08;margin:0 0 10px}.hero p{color:var(--muted);font-size:16px;line-height:1.5;margin:0}
.stats{display:grid;grid-template-columns:repeat(4,1fr);gap:10px;margin-top:18px}
.stat{background:var(--panel2);border:1px solid var(--line);border-radius:15px;padding:14px}.stat strong{font-size:22px;display:block}.stat span{color:var(--muted);font-size:12px}
.section-title{display:flex;justify-content:space-between;align-items:end;gap:10px;margin-bottom:12px}.section-title h3{margin:0;font-size:18px}.section-title span{color:var(--muted);font-size:13px}
.grid{display:grid;grid-template-columns:repeat(2,1fr);gap:10px}
.rangebtn,.modebtn{background:var(--panel2);color:var(--text);border:1px solid var(--line);padding:16px;text-align:left;min-height:80px}
.rangebtn b,.modebtn b{display:block;font-size:17px;margin-bottom:5px}.rangebtn span,.modebtn span{color:var(--muted);font-size:13px}
.rangebtn:active,.modebtn:active,.choice:active{transform:scale(.99)}
.custom{display:grid;grid-template-columns:1fr 1fr auto;gap:10px;margin-top:10px}
input,select{width:100%;background:#091628;color:var(--text);border:1px solid var(--line);border-radius:12px;padding:12px;outline:none}
input:focus,select:focus{border-color:var(--accent)}
.progressbar{height:8px;background:#0a1627;border-radius:999px;overflow:hidden;border:1px solid var(--line)}
.progressbar>div{height:100%;background:var(--accent);width:0}
.quiztop{display:grid;grid-template-columns:auto 1fr auto;align-items:center;gap:12px;margin-bottom:12px}
.centerstat{text-align:center}.centerstat b{display:block}.centerstat span{font-size:12px;color:var(--muted)}
.question-card{background:var(--panel);border:1px solid var(--line);border-radius:22px;padding:22px;box-shadow:var(--shadow)}
.meta{display:flex;flex-wrap:wrap;gap:8px;align-items:center;color:var(--muted);font-size:13px;margin-bottom:14px}
.badge{padding:5px 8px;border-radius:999px;border:1px solid var(--line);background:var(--panel2)}
.figure{color:var(--warn);border-color:rgba(242,200,107,.35)}
.qtext{font-size:22px;line-height:1.4;font-weight:700;margin:0 0 20px}
.choices{display:grid;gap:11px}
.choice{width:100%;background:#0b192b;color:var(--text);border:1px solid var(--line);padding:15px 16px;display:grid;grid-template-columns:38px 1fr;gap:10px;text-align:left;align-items:start;line-height:1.35}
.choice .letter{width:32px;height:32px;border-radius:10px;background:var(--panel2);display:grid;place-items:center;font-weight:900}
.choice:hover{border-color:#3b577d}
.choice.selected{border-color:var(--accent);background:#102744}
.choice.correct{border-color:var(--good);background:rgba(61,220,151,.12)}
.choice.wrong{border-color:var(--bad);background:rgba(255,112,112,.12)}
.choice.correct .letter{background:var(--good);color:#062015}.choice.wrong .letter{background:var(--bad);color:#2c0505}

.figuretools{margin:12px 0 4px;display:flex;flex-wrap:wrap;gap:8px;align-items:center}
.figureinline{width:100%;margin-top:6px;border:1px solid var(--line);background:#08111f;border-radius:16px;padding:10px}
.figureinline img{display:block;width:100%;height:auto;max-height:600px;object-fit:contain;background:white;border-radius:10px}
.figureinlinebar{display:flex;align-items:center;justify-content:space-between;gap:10px;margin-top:9px}
.figureinlinebar span{font-size:12px;color:var(--muted)}
.figuretools.hidden{display:none}
.figurehint{width:100%;font-size:13px;color:var(--muted)}
.figurebtn{border:1px solid var(--line);background:#0f172a;color:var(--text);border-radius:999px;padding:9px 12px;font-weight:700;cursor:pointer}
.figurebtn:hover{border-color:#35507a}
.figurebtn.secondary{background:transparent;color:var(--muted);font-weight:600}
.figureviewer{max-height:min(72vh,860px);overflow:auto;border:1px solid var(--line);border-radius:14px;background:#08111f;padding:10px}
.figureviewer img{width:100%;height:auto;border-radius:10px;display:block;background:white}
.figurenote{font-size:14px;color:var(--muted);line-height:1.5;margin:10px 0 0}
.figuretitle{margin:0 0 8px}
.feedback{margin-top:16px;border-radius:15px;padding:14px 15px;display:none;line-height:1.4}
.feedback.good{display:block;background:rgba(61,220,151,.10);border:1px solid rgba(61,220,151,.35)}
.feedback.bad{display:block;background:rgba(255,112,112,.10);border:1px solid rgba(255,112,112,.35)}
.actions{display:flex;justify-content:space-between;gap:10px;margin-top:16px;align-items:center}
.star.on{color:var(--warn);border-color:rgba(242,200,107,.45)}
.session-score{font-size:13px;color:var(--muted)}
.result{text-align:center;padding:30px 18px}.result .big{font-size:54px;font-weight:900;margin:4px 0}.result h2{font-size:26px;margin:0 0 6px}.result p{color:var(--muted)}
.resultgrid{display:grid;grid-template-columns:repeat(3,1fr);gap:10px;margin:18px 0}
.resultgrid div{background:var(--panel2);border:1px solid var(--line);border-radius:15px;padding:13px}
.resultgrid strong{display:block;font-size:20px}
.stack{display:grid;gap:10px}
.listrow{display:grid;grid-template-columns:1fr auto;gap:10px;align-items:center;padding:12px;border-bottom:1px solid var(--line)}
.listrow:last-child{border-bottom:0}.listrow small{color:var(--muted)}
.hidden{display:none!important}
.modal{position:fixed;inset:0;background:rgba(0,0,0,.6);display:grid;place-items:center;padding:20px;z-index:20}
.modalbox{background:var(--panel);border:1px solid var(--line);border-radius:20px;padding:20px;max-width:560px;width:100%;max-height:82vh;overflow:auto;box-shadow:var(--shadow)}
.modalbox h3{margin-top:0}
.footer{color:var(--muted);font-size:12px;text-align:center;padding:18px 5px 6px;line-height:1.45}
.small{font-size:12px;color:var(--muted)}
.welcome{min-height:calc(100vh - 36px);display:flex;flex-direction:column;justify-content:center;padding:24px 0}
.welcome-head{text-align:center;margin:0 auto 22px;max-width:680px}
.welcome-kicker{display:inline-block;padding:7px 10px;border:1px solid var(--line);border-radius:999px;background:var(--panel);color:var(--muted);font-size:12px;margin-bottom:14px}
.welcome-head h1{font-size:38px;line-height:1.08;margin:0 0 12px}
.welcome-head p{color:var(--muted);font-size:16px;line-height:1.5;margin:0}
.exam-grid{display:grid;grid-template-columns:repeat(3,1fr);gap:12px}
.exam-card{position:relative;background:var(--panel);border:1px solid var(--line);border-radius:20px;padding:20px;text-align:left;color:var(--text);min-height:180px;cursor:pointer;box-shadow:var(--shadow)}
.exam-card:hover{border-color:#3b577d}
.exam-card.active{border-color:rgba(102,167,255,.65);background:linear-gradient(145deg,#102744,#0e1b2f)}
.exam-card h3{font-size:20px;margin:32px 0 8px}
.exam-card p{color:var(--muted);line-height:1.4;margin:0;font-size:14px}
.exam-tag{position:absolute;top:16px;left:16px;padding:6px 9px;border-radius:999px;font-size:11px;font-weight:800;border:1px solid var(--line);background:var(--panel2);color:var(--muted)}
.exam-card.active .exam-tag{color:var(--accent);border-color:rgba(102,167,255,.4)}
.exam-arrow{position:absolute;right:16px;bottom:16px;font-size:22px;color:var(--accent)}
.range-actions{display:grid;grid-template-columns:1fr 1fr;gap:10px;margin-top:10px}
.back-exams{white-space:nowrap}
.soonbox{text-align:center}
.soonicon{font-size:42px;margin:4px 0 8px}
.legal-link{background:none;border:0;padding:0;color:var(--muted);text-decoration:underline;text-underline-offset:3px;cursor:pointer;font:inherit}
.legal-link:hover{color:var(--text)}
.legal-copy{color:var(--muted);line-height:1.55;font-size:14px}
.legal-copy strong{color:var(--text)}
@media (max-width:650px){
  .stats{grid-template-columns:repeat(2,1fr)}
  .grid{grid-template-columns:1fr}
  .exam-grid{grid-template-columns:1fr}
  .welcome{justify-content:flex-start;padding-top:36px}
  .welcome-head h1{font-size:31px}
  .exam-card{min-height:145px}
  .custom{grid-template-columns:1fr 1fr}
  .range-actions{grid-template-columns:1fr}
  .qtext{font-size:19px}
  .question-card{padding:17px}
}