:root {
  --bg: #0f0f11;
  --surface: #17171a;
  --border: #2a2a2f;
  --text: #e8e8ed;
  --muted: #6b6b78;
  --correct: #00c97a;
  --correct-bg: rgba(0,201,122,0.08);
  --wrong: #ef3c69;
  --wrong-bg: rgba(239,60,105,0.08);
  --mono: 'IBM Plex Mono', monospace;
  --sans: 'Inter', sans-serif;
}

* { box-sizing: border-box; margin: 0; padding: 0; }

body {
  background: var(--bg);
  color: var(--text);
  font-family: var(--sans);
  min-height: 100vh;
  padding: 2rem 1rem 4rem;
}

.container {
  max-width: 820px;
  margin: 0 auto;
}

/* Header */
.header { margin-bottom: 2.5rem; }

.header-label {
  font-family: var(--mono);
  font-size: 0.7rem;
  letter-spacing: 0.15em;
  color: var(--muted);
  text-transform: uppercase;
  margin-bottom: 0.5rem;
}

.header-title {
  font-size: 1.6rem;
  font-weight: 600;
  letter-spacing: -0.03em;
}

.header-sub {
  margin-top: 0.4rem;
  font-size: 0.85rem;
  color: var(--muted);
  font-family: var(--mono);
}

/* Questions list */
.questions-list {
  display: flex;
  flex-direction: column;
  gap: 0.6rem;
}

.question-card {
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: 10px;
  overflow: hidden;
  padding: 1rem 1.2rem;
}

.question-top {
  display: flex;
  align-items: flex-start;
  gap: 1rem;
  margin-bottom: 0.75rem;
}

.q-num {
  font-family: var(--mono);
  font-size: 0.85rem;
  color: var(--muted);
  flex-shrink: 0;
  padding-top: 0.1rem;
  min-width: 2rem;
}

.q-text {
  font-size: 0.92rem;
  line-height: 1.6;
  flex: 1;
}

/* Passage */
.passage-block {
  flex: 1;
  display: flex;
  flex-direction: column;
  gap: 0.6rem;
}

.passage-text {
  font-size: 0.84rem;
  color: #c0c0cc;
  line-height: 1.75;
  padding: 0.85rem 1rem;
  background: rgba(255,255,255,0.02);
  border-radius: 7px;
  border-left: 2px solid var(--border);
  position: relative;
  overflow: hidden;
  transition: max-height 0.4s ease, opacity 0.3s ease;
}

.passage-text.collapsed {
  max-height: 3.8rem;
  -webkit-mask-image: linear-gradient(to bottom, black 40%, transparent 100%);
  mask-image: linear-gradient(to bottom, black 40%, transparent 100%);
  cursor: pointer;
}

.passage-text.read {
  max-height: none;
  -webkit-mask-image: none;
  mask-image: none;
  cursor: default;
  color: var(--muted);
}

.passage-toggle {
  font-family: var(--mono);
  font-size: 0.7rem;
  color: var(--muted);
  cursor: pointer;
  background: none;
  border: none;
  padding: 0;
  text-align: left;
  letter-spacing: 0.05em;
  transition: color 0.15s;
}

.passage-toggle:hover { color: var(--text); }
.passage-toggle.hidden { display: none; }

.passage-question {
  font-size: 0.92rem;
  line-height: 1.55;
}

/* Options */
.options-grid {
  display: grid;
  gap: 0.35rem;
  padding-left: 3rem;
}

.option {
  display: flex;
  align-items: flex-start;
  gap: 0.65rem;
  padding: 0.5rem 0.75rem;
  border-radius: 7px;
  font-size: 0.84rem;
  line-height: 1.45;
  background: rgba(255,255,255,0.025);
  border: 1px solid transparent;
  color: var(--text);
  cursor: pointer;
  transition: border-color 0.12s, background 0.12s;
  user-select: none;
  -webkit-user-select: none;
}

.option:hover {
  border-color: var(--border);
  background: rgba(255,255,255,0.04);
}

.option.selected-correct {
  border-color: var(--correct);
  background: var(--correct-bg);
}

.option.selected-wrong {
  border-color: var(--wrong);
  background: var(--wrong-bg);
}

.option-letter {
  font-family: var(--mono);
  font-size: 0.65rem;
  color: var(--muted);
  flex-shrink: 0;
  padding-top: 0.2rem;
  min-width: 1rem;
}

.option.selected-correct .option-letter { color: var(--correct); }
.option.selected-wrong .option-letter { color: var(--wrong); }