/* MedExam 115 — Giao diện học viên. Mobile-first, tự giãn trên desktop. */
:root{
  --blue:#1d6ff2;--blue-b:#1a63d8;--ink:#111827;--ink2:#344054;--muted:#667085;--muted2:#98a2b3;
  --line:#e7eaf0;--line2:#eef1f5;--bg:#f3f5f9;--green:#16a34a;--green-b:#138a3f;--amber:#b86b14;--red:#d92d20;
  --blue-soft:#e9f1ff;
}
*{box-sizing:border-box;-webkit-tap-highlight-color:transparent}
html,body{margin:0;padding:0}
body{font-family:'Public Sans',-apple-system,BlinkMacSystemFont,'Segoe UI',system-ui,sans-serif;
  color:var(--ink);background:var(--bg);-webkit-font-smoothing:antialiased}
.num{font-variant-numeric:tabular-nums;letter-spacing:.01em}
svg{flex-shrink:0}
[x-cloak]{display:none!important}

/* Khung: mobile full, desktop có card giữa */
.exam-shell{min-height:100vh;display:flex;flex-direction:column;max-width:520px;margin:0 auto;background:var(--bg)}
@media(min-width:560px){.exam-shell{min-height:100vh;box-shadow:0 0 60px -20px rgba(12,44,84,.25)}}

/* ---- Lock / nhập mã ---- */
.enter{flex:1;display:flex;flex-direction:column;justify-content:center;gap:24px;padding:32px 26px}
.enter .hero{display:flex;flex-direction:column;align-items:center;gap:16px;text-align:center}
.enter .logo{width:82px;height:82px;border-radius:22px;background:#fff;display:flex;align-items:center;justify-content:center;
  box-shadow:0 12px 28px -12px rgba(29,111,242,.45);overflow:hidden}
.enter .logo img{width:66px;height:66px;object-fit:contain}
.enter h1{font-size:24px;font-weight:800;letter-spacing:-.03em;margin:0}
.enter h1 span{color:var(--blue)}
.enter .tag{font-size:13.5px;color:var(--muted);font-weight:500;margin-top:4px}
.enter .box{background:#fff;border:1px solid var(--line);border-radius:16px;padding:22px 20px;
  box-shadow:0 4px 14px rgba(16,24,40,.05);display:flex;flex-direction:column;gap:16px}
.enter label{display:flex;flex-direction:column;gap:7px;font-size:12px;font-weight:700;color:var(--muted)}
.enter input{font-family:inherit;font-size:15px;font-weight:600;color:var(--ink);padding:13px 14px;border:1px solid var(--line);
  border-radius:10px;outline:none;background:#f8fafc}
.enter input:focus{border-color:var(--blue);background:#fff;box-shadow:0 0 0 3px rgba(29,111,242,.12)}
.enter .foot{text-align:center;font-size:12.5px;color:#8b97a8;line-height:1.6}

.btn{display:flex;align-items:center;justify-content:center;gap:8px;font-family:inherit;font-weight:700;cursor:pointer;
  border-radius:12px;border:1px solid transparent;font-size:15px;padding:15px}
.btn-blue{background:linear-gradient(180deg,#3b82f6,var(--blue));color:#fff;border-color:var(--blue-b);box-shadow:0 4px 12px rgba(29,111,242,.35)}
.btn-green{background:linear-gradient(180deg,#1fb15d,var(--green));color:#fff;border-color:var(--green-b);box-shadow:0 4px 14px rgba(22,163,74,.35)}
.btn-ghost{background:#fff;color:var(--ink2);border:1px solid var(--line)}
.btn:disabled{opacity:.55;cursor:not-allowed}

/* ---- Intro ---- */
.intro{flex:1;overflow-y:auto;padding:20px 22px 26px}
.intro .back{display:inline-flex;align-items:center;gap:6px;color:var(--muted);font-size:13.5px;font-weight:600;margin-bottom:14px;cursor:pointer;background:none;border:none}
.intro .banner{background:linear-gradient(135deg,#3b82f6,var(--blue));border-radius:18px;padding:22px;color:#fff;box-shadow:0 12px 26px -14px rgba(29,111,242,.7)}
.intro .banner .k{font-size:11.5px;font-weight:700;letter-spacing:.4px;text-transform:uppercase;color:#c7dbfb}
.intro .banner h2{font-size:20px;font-weight:800;margin:6px 0 0;line-height:1.3}
.intro .banner .c{font-size:13px;color:#dbe8fc;margin-top:8px;font-weight:500}
.intro .facts{display:grid;grid-template-columns:1fr 1fr;gap:12px;margin-top:16px}
.intro .fact{background:#fff;border:1px solid var(--line);border-radius:14px;padding:15px}
.intro .fact .l{font-size:12px;color:var(--muted);font-weight:600}
.intro .fact .v{font-size:22px;font-weight:800;margin-top:3px}
.intro .note{background:#fff;border:1px solid var(--line);border-radius:14px;padding:16px 18px;margin-top:14px}
.intro .note .h{display:flex;align-items:center;gap:8px;font-size:13.5px;font-weight:700;margin-bottom:10px}
.intro .note .li{display:flex;gap:9px;font-size:13px;color:#475467;line-height:1.5;margin-bottom:9px}
.intro .note .li b{color:var(--green)}

/* ---- Exam ---- */
.exam{flex:1;display:flex;flex-direction:column;min-height:0;height:100vh}
.exam .top{flex:0 0 auto;padding:14px 20px 12px;border-bottom:1px solid var(--line);background:#fff}
.exam .topbar{display:flex;align-items:center;justify-content:space-between;margin-bottom:10px}
.exam .qn{font-size:13px;font-weight:700;color:var(--ink2)}
.exam .qn i{color:var(--muted2);font-weight:600;font-style:normal}
.timer{display:flex;align-items:center;gap:7px;padding:6px 12px;border-radius:999px;font-weight:700}
.timer.ok{background:var(--blue-soft);color:var(--blue)}
.timer.warn{background:#fef2e6;color:var(--amber)}
.timer.crit{background:#fdeceb;color:var(--red)}
.bar{height:6px;background:#e9edf3;border-radius:6px;overflow:hidden}
.bar>i{display:block;height:100%;background:linear-gradient(90deg,#3b82f6,var(--blue));border-radius:6px;transition:width .3s}
.exam .body{flex:1;overflow-y:auto;padding:18px 20px 16px}
.chips{display:flex;gap:8px;flex-wrap:wrap;margin-bottom:14px}
.chip{font-size:11.5px;font-weight:700;padding:4px 10px;border-radius:999px}
.chip.blue{color:#1e40af;background:var(--blue-soft)}
.chip.gray{color:var(--muted);background:var(--bg)}
.stem{font-size:16.5px;font-weight:700;line-height:1.5;color:var(--ink);letter-spacing:-.01em}
.q-img{margin-top:14px;max-width:100%;border-radius:12px;border:1px solid var(--line)}
.multi-hint{margin-top:10px;font-size:12.5px;color:var(--amber);font-weight:700}
.opts{display:flex;flex-direction:column;gap:10px;margin-top:16px}
.opt{display:flex;align-items:flex-start;gap:12px;padding:14px 15px;border:1.5px solid var(--line);border-radius:13px;
  background:#fff;cursor:pointer;transition:border-color .12s,background .12s}
.opt:hover{border-color:#c7d0dd}
.opt.sel{border-color:var(--blue);background:var(--blue-soft)}
.opt .mk{width:30px;height:30px;flex:0 0 auto;border-radius:9px;border:1.5px solid var(--line);display:flex;align-items:center;
  justify-content:center;font-weight:800;font-size:13px;color:var(--ink2);background:#fff}
.opt.sel .mk{background:var(--blue);border-color:var(--blue);color:#fff}
.opt .tx{font-size:15px;font-weight:500;line-height:1.4;padding-top:4px}
.exam .foot{flex:0 0 auto;border-top:1px solid var(--line);background:#fff;padding:12px 18px 18px;position:relative}
.saved{position:absolute;top:-30px;left:50%;transform:translateX(-50%);background:var(--green);color:#fff;font-size:12px;
  font-weight:700;padding:6px 14px;border-radius:999px;display:flex;align-items:center;gap:6px;
  opacity:0;pointer-events:none}
.saved.show{animation:savepulse 2s ease forwards}
@keyframes savepulse{0%{opacity:0;transform:translate(-50%,4px)}18%{opacity:1;transform:translate(-50%,0)}82%{opacity:1}100%{opacity:0}}
.foot-row{display:flex;gap:10px;align-items:center}
.icon-btn{flex:0 0 auto;width:52px;height:52px;border-radius:12px;border:1px solid var(--line);background:#fff;color:var(--ink2);
  cursor:pointer;display:flex;align-items:center;justify-content:center}
.icon-btn:disabled{opacity:.4}
.flag-btn{flex:0 0 auto;height:52px;padding:0 14px;border-radius:12px;border:1px solid var(--line);background:#fff;color:var(--ink2);
  cursor:pointer;display:flex;align-items:center;gap:7px;font-weight:600;font-family:inherit;font-size:13px}
.flag-btn.on{background:#fbf0df;border-color:#d9a441;color:var(--amber)}
.next-btn{flex:1;height:52px;border-radius:12px;border:1px solid var(--blue-b);background:linear-gradient(180deg,#3b82f6,var(--blue));
  color:#fff;font-size:15px;font-weight:700;font-family:inherit;cursor:pointer;display:flex;align-items:center;justify-content:center;gap:7px}

/* palette bottom sheet */
.sheet-mask{position:fixed;inset:0;background:rgba(15,23,42,.45);z-index:30;display:flex;flex-direction:column;justify-content:flex-end}
.sheet{background:#fff;border-radius:24px 24px 0 0;padding:22px 22px 28px;animation:sheetUp .28s ease;max-width:520px;margin:0 auto;width:100%}
@keyframes sheetUp{from{transform:translateY(100%)}to{transform:none}}
.sheet .grip{width:40px;height:4px;border-radius:4px;background:#d3dae4;margin:0 auto 16px}
.sheet h3{font-size:16px;font-weight:800;margin:0 0 4px}
.legend{display:flex;gap:14px;font-size:12px;color:var(--muted);font-weight:600;margin:8px 0 16px;flex-wrap:wrap}
.legend span{display:flex;align-items:center;gap:5px}
.legend i{width:11px;height:11px;border-radius:4px;display:block}
.pgrid{display:grid;grid-template-columns:repeat(5,1fr);gap:10px}
.pcell{aspect-ratio:1;border-radius:11px;border:1.5px solid #cbd5e1;background:#fff;font-weight:700;font-family:inherit;
  cursor:pointer;font-size:15px;color:var(--ink2);display:flex;align-items:center;justify-content:center}
.pcell.done{background:var(--blue);border-color:var(--blue);color:#fff}
.pcell.flag{background:#fbf0df;border-color:#d9a441;color:var(--amber)}
.pcell.cur{outline:3px solid rgba(29,111,242,.35)}

/* ---- Submit / Result ---- */
.pane{flex:1;overflow-y:auto;padding:20px 24px 28px;display:flex;flex-direction:column}
.pane .center{text-align:center;margin-bottom:22px}
.pane .badge-ic{width:64px;height:64px;border-radius:18px;background:var(--blue-soft);color:var(--blue);display:flex;
  align-items:center;justify-content:center;margin:0 auto 14px}
.pane h2{font-size:20px;font-weight:800;letter-spacing:-.02em;margin:0}
.pane .sub{font-size:13.5px;color:var(--muted);margin-top:6px}
.summary{background:#fff;border:1px solid var(--line);border-radius:14px;padding:6px 18px}
.summary .r{display:flex;justify-content:space-between;padding:14px 0;border-bottom:1px solid var(--line2)}
.summary .r:last-child{border-bottom:none}
.summary .r span{color:var(--muted);font-size:14px;font-weight:500}
.summary .r b{font-weight:700;font-size:14px}
.result-hero{border-radius:20px;padding:26px 22px;color:#fff;text-align:center;box-shadow:0 14px 30px -16px rgba(16,24,40,.55)}
.result-hero.pass{background:linear-gradient(135deg,#1fb15d,#0f8a43)}
.result-hero.fail{background:linear-gradient(135deg,#f0685e,#d92d20)}
.result-hero .k{font-size:12px;font-weight:700;letter-spacing:.4px;text-transform:uppercase;opacity:.92}
.result-hero .score{font-size:54px;font-weight:800;line-height:1;margin:10px 0 4px}
.result-hero .meta{font-size:14px;font-weight:500;opacity:.9}
.spin{margin-top:auto}