:root {
  --bg: #0c1620;
  --panel: #111c2b;
  --card: #182437;
  --border: rgba(255, 255, 255, 0.14);
  --text: #edf4ff;
  --muted: #9fb0c8;
  --accent: #7cf0bd;
  --accent-2: #ffe07a;
  font-family: "IBM Plex Sans", "Segoe UI", sans-serif;
}

* { box-sizing: border-box; }
body {
  margin: 0;
  min-height: 100vh;
  color: var(--text);
  background:
    radial-gradient(circle at top left, rgba(124, 240, 189, 0.16), transparent 30%),
    linear-gradient(180deg, #0b1320, #132236);
}

.page {
  max-width: 1080px;
  margin: 0 auto;
  padding: 24px 16px 48px;
}

.hero, .card {
  background: var(--panel);
  border: 1px solid var(--border);
  border-radius: 24px;
  box-shadow: 0 24px 60px rgba(0, 0, 0, 0.28);
}

.hero { padding: 24px; }
.hero h1 { margin: 0 0 8px; font-size: clamp(2rem, 5vw, 3rem); }
.hero p { margin: 0; color: var(--muted); }

.toolbar, .question-wrap {
  margin-top: 20px;
  padding: 20px;
}

.toolbar {
  display: grid;
  gap: 16px;
}

.tabs, .actions {
  display: flex;
  gap: 10px;
  flex-wrap: wrap;
}

button, input {
  font: inherit;
}

.tab, .secondary, .option {
  border: 1px solid var(--border);
  background: rgba(255, 255, 255, 0.03);
  color: var(--text);
}

.tab, .secondary, .primary, .option {
  border-radius: 16px;
  padding: 12px 16px;
}

.tab.active {
  background: rgba(124, 240, 189, 0.12);
  border-color: var(--accent);
}

.search {
  width: 100%;
  background: rgba(255, 255, 255, 0.03);
  border: 1px solid var(--border);
  border-radius: 16px;
  color: var(--text);
  padding: 14px 16px;
}

.primary {
  background: linear-gradient(120deg, var(--accent), var(--accent-2));
  color: #172129;
  border: none;
  font-weight: 700;
}

.question-head {
  display: flex;
  justify-content: space-between;
  gap: 16px;
  align-items: baseline;
}

.meta { color: var(--muted); }
.prompt { font-size: 1.25rem; line-height: 1.55; margin: 20px 0; }
.options { display: grid; gap: 12px; }

.option {
  width: 100%;
  text-align: left;
  cursor: pointer;
}
.option.selected { border-color: #7db8ff; background: rgba(125, 184, 255, 0.12); }
.option.correct { border-color: var(--accent); background: rgba(124, 240, 189, 0.12); }
.option.wrong { border-color: #ff8fa3; background: rgba(255, 143, 163, 0.12); }
.option-label {
  display: inline-flex;
  width: 28px;
  font-weight: 700;
  color: var(--accent);
}

.answer-box {
  margin-top: 18px;
  padding: 16px;
  border-radius: 18px;
  border: 1px solid rgba(124, 240, 189, 0.2);
  background: rgba(124, 240, 189, 0.07);
  white-space: pre-line;
}

.answer-box.hidden { display: none; }
.helper { color: var(--muted); margin-top: 10px; }