:root{
  --bg: #0b0f14;
  --card: #101826;
  --card2: #0e1521;
  --text: #e8eef7;
  --muted: #9fb2c9;
  --line: rgba(255,255,255,.10);
  --primary: #3b82f6;
  --danger: #ef4444;
  --ok: #22c55e;
  --shadow: 0 18px 50px rgba(0,0,0,.45);
}

*{ box-sizing:border-box; }
html,body{ height:100%; }
body{
  margin:0;
  font-family: ui-sans-serif, system-ui, -apple-system, Segoe UI, Roboto, Helvetica, Arial, "Apple Color Emoji", "Segoe UI Emoji";
  background: radial-gradient(1200px 800px at 20% 10%, rgba(59,130,246,.18), transparent 60%),
              radial-gradient(900px 700px at 80% 0%, rgba(34,197,94,.10), transparent 55%),
              var(--bg);
  color: var(--text);
}

.wrap{ min-height:100%; padding: 22px; }

.topbar{
  max-width: 980px;
  margin: 0 auto 16px;
  display:flex;
  align-items:flex-end;
  justify-content:space-between;
  gap: 16px;
}

.topActions{ display:flex; align-items:center; gap: 10px; }
.main{ max-width: 980px; margin: 0 auto; display:grid; gap: 14px; }

.pill{
  display:inline-flex;
  align-items:center;
  gap: 6px;
  padding: 6px 10px;
  border-radius: 999px;
  background: rgba(255,255,255,.06);
  border: 1px solid rgba(255,255,255,.12);
  font-size: 12px;
  color: var(--muted);
}

.practiceHead{ display:flex; align-items:baseline; justify-content:space-between; gap: 12px; }
.practiceMeta{ display:flex; gap: 8px; flex-wrap:wrap; }

.prompt{ font-size: 16px; line-height: 1.35; margin-top: 10px; }
.hint{ font-size: 13px; color: var(--muted); margin-top: 8px; }
.brandTitle{ font-size: 28px; font-weight: 800; letter-spacing: .2px; }
.brandSubtitle{ font-size: 14px; color: var(--muted); margin-top: 4px; }

.userBar{ display:flex; align-items:center; gap: 10px; }
.userLabel{ color: var(--muted); font-size: 13px; }

.container{ max-width: 980px; margin: 0 auto; display:grid; gap: 14px; }

.card{
  background: linear-gradient(180deg, var(--card), var(--card2));
  border: 1px solid var(--line);
  border-radius: 16px;
  padding: 16px;
  box-shadow: var(--shadow);
}

.cardHeader{ display:flex; align-items:baseline; justify-content:space-between; gap: 12px; margin-bottom: 10px; }
.cardHeader h2{ margin:0; font-size: 18px; }
.small{ font-size: 13px; }

.field{ display:grid; gap: 6px; }
.field label{ font-size: 13px; color: var(--muted); }

input{
  width: 100%;
  background: rgba(255,255,255,.04);
  border: 1px solid rgba(255,255,255,.12);
  border-radius: 12px;
  color: var(--text);
  padding: 12px 12px;
  outline: none;
}
input:focus{ border-color: rgba(59,130,246,.7); box-shadow: 0 0 0 4px rgba(59,130,246,.15); }

.row{ display:flex; gap: 10px; align-items:center; flex-wrap: wrap; }
.mt{ margin-top: 12px; }

.btn{
  border: 1px solid rgba(255,255,255,.14);
  background: rgba(255,255,255,.06);
  color: var(--text);
  padding: 10px 12px;
  border-radius: 12px;
  cursor:pointer;
}
.btn:hover{ background: rgba(255,255,255,.09); }
.btn.primary{ background: rgba(59,130,246,.22); border-color: rgba(59,130,246,.5); }
.btn.primary:hover{ background: rgba(59,130,246,.30); }
.btn.ghost{ background: transparent; }
.btn:disabled{ opacity:.55; cursor:not-allowed; }

.inlineMsg{ font-size: 13px; color: var(--muted); }
.inlineMsg.error{ color: #fecaca; }
.inlineMsg.ok{ color: #bbf7d0; }

.hidden{ display:none !important; }

.exerciseTitle{ font-size: 16px; font-weight: 700; margin-bottom: 6px; }
.exercisePrompt{ color: var(--muted); font-size: 14px; margin-bottom: 10px; line-height: 1.35; }

.feedback{
  margin-top: 12px;
  padding: 12px;
  border-radius: 12px;
  border: 1px solid var(--line);
  background: rgba(255,255,255,.03);
}
.feedback.ok{ border-color: rgba(34,197,94,.45); }
.feedback.bad{ border-color: rgba(239,68,68,.45); }

.footer{
  max-width: 980px;
  margin: 16px auto 0;
  color: var(--muted);
  font-size: 13px;
  display:flex;
  gap: 10px;
  align-items:center;
  justify-content:center;
  flex-wrap:wrap;
}
.sep{ opacity: .6; }
.footerBy{ opacity: .85; }

@media (max-width: 540px){
  .topbar{ align-items:flex-start; flex-direction: column; }
}


.levelSelect{
  appearance: none;
  border: 1px solid var(--line);
  background: rgba(255,255,255,.04);
  color: var(--text);
  padding: 6px 10px;
  border-radius: 999px;
  font-size: 12px;
}
.levelSelect:focus{
  outline: none;
  border-color: rgba(255,255,255,.25);
}