:root{
  --bg:#020617;
  --card:#0b1220;
  --card2:#0f172a;
  --text:#e5e7eb;
  --muted:#94a3b8;
  --accent:#3b82f6;
  --accent2:#22c55e;
  --danger:#ef4444;
  --border:rgba(148,163,184,0.28);
}
*{box-sizing:border-box}
body{
  margin:0;
  font-family: ui-sans-serif, system-ui, -apple-system, Segoe UI, Roboto, Arial, "Noto Sans", "Apple Color Emoji","Segoe UI Emoji";
  color:var(--text);
  background:
    radial-gradient(circle at 0% 0%, rgba(59,130,246,0.20), transparent 50%),
    radial-gradient(circle at 100% 100%, rgba(34,197,94,0.15), transparent 55%),
    linear-gradient(135deg, #020617, #020617);
  min-height:100vh;
}
main{display:flex;align-items:center;justify-content:center;min-height:100vh;padding:20px}
.card-large{
  width:min(820px, 96vw);
  background:linear-gradient(180deg, rgba(15,23,42,0.92), rgba(2,6,23,0.92));
  border:1px solid var(--border);
  border-radius:20px;
  box-shadow: 0 18px 60px rgba(0,0,0,0.5);
  overflow:hidden;
}
.card-inner{padding:28px}
.card-title{margin:0 0 8px;font-size:2rem;letter-spacing:0.3px}
.card-subtitle{margin:0 0 18px;color:var(--muted);line-height:1.45}
.code-row{display:flex;gap:10px;align-items:center;flex-wrap:wrap}
.code-input{
  flex:1;
  min-width:240px;
  padding:14px 14px;
  border-radius:14px;
  background:rgba(2,6,23,0.75);
  border:1px solid rgba(148,163,184,0.35);
  color:var(--text);
  font-size:1rem;
  outline:none;
}
.btn-primary{
  display:inline-flex;gap:10px;align-items:center;justify-content:center;
  padding:14px 18px;border-radius:14px;border:1px solid rgba(59,130,246,0.55);
  background:rgba(59,130,246,0.18);
  color:var(--text);cursor:pointer;font-weight:700;
  transition:transform .12s ease, background .12s ease;
}
.btn-primary:hover{transform:translateY(-1px);background:rgba(59,130,246,0.26)}
.status-text{margin-top:10px;color:var(--muted);font-size:0.9rem}
.status-text.error{color:#fecaca}
.fade-out{animation:fadeOut .35s ease forwards}
@keyframes fadeOut{to{opacity:0;transform:translateY(3px)}}
.shake{animation:shake .28s ease}
@keyframes shake{
  0%,100%{transform:translateX(0)}
  25%{transform:translateX(-6px)}
  75%{transform:translateX(6px)}
}
.page-shell{max-width:1200px;margin:18px auto;padding:0 14px 22px}
.exam-header{
  display:flex;justify-content:space-between;align-items:flex-start;gap:14px;flex-wrap:wrap;
  background:rgba(15,23,42,0.65);
  border:1px solid var(--border);
  border-radius:18px;
  padding:16px 16px;
  box-shadow:0 12px 40px rgba(0,0,0,0.35);
}
.exam-title-block h1{margin:0 0 4px;font-size:1.35rem}
.exam-title-block p{margin:0;color:var(--muted);font-size:0.9rem}
.badge{
  display:inline-flex;gap:8px;align-items:center;
  border-radius:999px;padding:8px 12px;
  border:1px solid var(--border);
  background:rgba(2,6,23,0.65);
}
.badge-time{border-color:rgba(59,130,246,0.55)}
.timer-label{font-weight:700}
.summary-row{display:flex;gap:10px;flex-wrap:wrap;align-items:center;margin:12px 2px;color:var(--muted);font-size:0.9rem}
.questions-grid{
  display:grid;
  grid-template-columns:repeat(auto-fit,minmax(240px,1fr));
  gap:12px;
}
.task-card{
  background:rgba(15,23,42,0.55);
  border:1px solid var(--border);
  border-radius:16px;
  overflow:hidden;
  box-shadow:0 10px 30px rgba(0,0,0,0.25);
  transform:translateY(0);
  transition:transform .12s ease, border-color .12s ease;
}
.task-card:hover{transform:translateY(-2px);border-color:rgba(59,130,246,0.5)}
.task-top{padding:10px 12px;border-bottom:1px solid rgba(148,163,184,0.18);display:flex;justify-content:space-between;align-items:center;gap:10px}
.task-title{font-weight:800;font-size:0.95rem}
.tag{font-size:0.72rem;color:var(--muted);border:1px solid rgba(148,163,184,0.28);padding:3px 8px;border-radius:999px}
.task-preview{background:rgba(2,6,23,0.8);padding:10px;min-height:110px;display:flex;align-items:center;justify-content:center}
.task-bottom{padding:10px 12px;display:flex;justify-content:space-between;align-items:center;gap:10px}
.btn-ghost{border-radius:999px;border:1px solid rgba(148,163,184,0.45);background:rgba(2,6,23,0.45);color:var(--text);padding:8px 12px;cursor:pointer;font-weight:700;font-size:0.82rem}
.btn-ghost:hover{background:rgba(59,130,246,0.18);border-color:rgba(59,130,246,0.45)}
.pill{display:inline-flex;gap:6px;align-items:center;border-radius:999px;padding:5px 10px;border:1px solid rgba(148,163,184,0.35);font-size:0.78rem;color:var(--muted)}
.pill.good{border-color:rgba(34,197,94,0.6);background:rgba(34,197,94,0.12);color:#bbf7d0}
.pill.bad{border-color:rgba(239,68,68,0.6);background:rgba(239,68,68,0.12);color:#fecaca}
.submit-row{display:flex;justify-content:center;margin:14px 0}
.btn-submit{
  padding:12px 18px;border-radius:999px;border:1px solid rgba(59,130,246,0.55);
  background:rgba(59,130,246,0.18);
  color:var(--text);font-weight:900;cursor:pointer;
}
.btn-submit:hover{background:rgba(59,130,246,0.26)}
.results-box{
  margin-top:14px;
  border:1px solid var(--border);
  border-radius:16px;
  padding:14px 14px;
  background:rgba(15,23,42,0.65);
  display:none;
}
.results-box.visible{display:block}
.badge2{display:inline-block;padding:4px 10px;border-radius:999px;font-weight:800;font-size:0.82rem;border:1px solid var(--border)}
.badge2.good{border-color:rgba(34,197,94,0.6);background:rgba(34,197,94,0.12);color:#bbf7d0}
.badge2.ok{border-color:rgba(250,204,21,0.65);background:rgba(250,204,21,0.12);color:#fef9c3}
.badge2.bad{border-color:rgba(239,68,68,0.6);background:rgba(239,68,68,0.12);color:#fecaca}

/* Modal */
.modal-backdrop{position:fixed;inset:0;background:rgba(2,6,23,0.75);display:flex;align-items:center;justify-content:center;padding:14px;z-index:999}
.modal{width:min(980px,96vw);background:rgba(15,23,42,0.92);border:1px solid rgba(148,163,184,0.35);border-radius:18px;box-shadow:0 24px 80px rgba(0,0,0,0.55);overflow:hidden}
.modal-head{display:flex;justify-content:space-between;align-items:center;padding:12px 14px;border-bottom:1px solid rgba(148,163,184,0.18)}
.modal-title{font-weight:900}
.modal-close{background:transparent;border:none;color:var(--text);font-size:1.6rem;cursor:pointer}
.modal-body{padding:12px 14px}
.canvas{background:#020617;border:1px solid rgba(148,163,184,0.35);border-radius:14px}
.hint{color:var(--muted);font-size:0.86rem;margin:0 0 10px;line-height:1.4}
.controls{display:flex;gap:10px;flex-wrap:wrap;align-items:center;margin-top:10px}
.kbd{font-family:ui-monospace,SFMono-Regular,Menlo,Monaco,Consolas,monospace;font-size:0.75rem;padding:2px 6px;border-radius:6px;background:rgba(148,163,184,0.12);border:1px solid rgba(148,163,184,0.35)}