:root {
  --primary: #6d5ef1;
  --primary-dark: #5545d6;
  --ok: #21b573;
  --ng: #f1475a;
  --bg: #f6f5fb;
  --card-bg: #ffffff;
  --text: #2b2a3d;
  --text-mute: #757389;
  --border: #e6e4f2;
  --radius: 16px;
}

* { box-sizing: border-box; }

body {
  margin: 0;
  font-family: -apple-system, BlinkMacSystemFont, "Apple SD Gothic Neo", "Malgun Gothic", "Segoe UI", sans-serif;
  background: var(--bg);
  color: var(--text);
  -webkit-font-smoothing: antialiased;
}

#app {
  max-width: 560px;
  margin: 0 auto;
  padding: 16px 16px 48px;
}

.screen { display: none; }
.screen.active { display: block; }

.app-header { text-align: center; margin: 12px 0 20px; }
.app-header h1 { margin: 0 0 4px; font-size: 26px; }
.subtitle { color: var(--text-mute); margin: 0; font-size: 14px; }

.card {
  background: var(--card-bg);
  border-radius: var(--radius);
  padding: 18px;
  margin-bottom: 14px;
  box-shadow: 0 2px 10px rgba(60, 50, 120, 0.06);
}

.field-label {
  display: block;
  font-weight: 700;
  font-size: 14px;
  margin: 12px 0 6px;
}
.field-label:first-child { margin-top: 0; }

.hint { font-weight: 400; color: var(--text-mute); font-size: 12px; }

.input {
  width: 100%;
  padding: 12px 14px;
  border: 1.5px solid var(--border);
  border-radius: 12px;
  font-size: 15px;
  background: #fff;
  color: var(--text);
  font-family: inherit;
}
.input:focus { outline: none; border-color: var(--primary); }
.textarea { resize: vertical; line-height: 1.5; }

.hidden { display: none !important; }

.checks { display: flex; flex-wrap: wrap; gap: 8px; margin-top: 4px; }
.chip {
  display: inline-flex; align-items: center; gap: 6px;
  padding: 8px 12px; border: 1.5px solid var(--border); border-radius: 999px;
  font-size: 13.5px; cursor: pointer; background: #fff;
}
.chip input { accent-color: var(--primary); }

.mode-tabs { display: flex; gap: 8px; margin-bottom: 4px; }
.mode-tab {
  flex: 1; padding: 12px; border-radius: 12px; border: 1.5px solid var(--border);
  background: #fff; font-size: 14px; font-weight: 700; color: var(--text-mute); cursor: pointer;
}
.mode-tab.active { background: var(--primary); color: #fff; border-color: var(--primary); }

.pill-select { display: flex; gap: 8px; flex-wrap: wrap; }
.pill {
  padding: 8px 14px; border-radius: 999px; border: 1.5px solid var(--border);
  background: #fff; font-size: 13.5px; cursor: pointer; color: var(--text);
}
.pill.active { background: var(--primary-dark); border-color: var(--primary-dark); color: #fff; }

.btn {
  display: inline-block; border: none; border-radius: 12px; padding: 13px 18px;
  font-size: 15px; font-weight: 700; cursor: pointer; font-family: inherit;
}
.btn-primary { background: var(--primary); color: #fff; }
.btn-primary:active { background: var(--primary-dark); }
.btn-primary:disabled { background: #c9c5ee; cursor: not-allowed; }
.btn-secondary { background: var(--text); color: #fff; }
.btn-outline { background: #fff; color: var(--primary); border: 1.5px solid var(--primary); }
.btn-big { width: 100%; padding: 15px; font-size: 16px; margin-top: 6px; }

.admin-link { text-align: center; margin-top: 10px; }
.admin-link a { color: var(--text-mute); font-size: 13px; text-decoration: none; }

/* -------- Quiz screen -------- */
.quiz-topbar {
  display: flex; justify-content: space-between; align-items: center;
  margin: 10px 0 14px; font-size: 14px; color: var(--text-mute);
}
.timer {
  font-weight: 800; font-size: 18px; color: var(--primary-dark);
  background: #fff; padding: 6px 14px; border-radius: 999px;
  box-shadow: 0 2px 8px rgba(60,50,120,0.08);
}
.timer.urgent { color: var(--ng); }

.loading { text-align: center; padding: 60px 0; color: var(--text-mute); }
.spinner {
  width: 36px; height: 36px; border-radius: 50%;
  border: 4px solid var(--border); border-top-color: var(--primary);
  margin: 0 auto 14px; animation: spin 0.8s linear infinite;
}
@keyframes spin { to { transform: rotate(360deg); } }

.question-card { }
.type-badge {
  display: inline-block; background: #efebff; color: var(--primary-dark);
  font-size: 12px; font-weight: 800; padding: 4px 10px; border-radius: 999px; margin-bottom: 10px;
}
.stem { font-size: 17px; line-height: 1.6; font-weight: 600; margin: 0 0 16px; white-space: pre-wrap; }

.choice-list { display: flex; flex-direction: column; gap: 8px; margin-bottom: 6px; }
.choice-item {
  display: flex; align-items: center; gap: 10px;
  padding: 12px 14px; border: 1.5px solid var(--border); border-radius: 12px; cursor: pointer;
  font-size: 14.5px;
}
.choice-item.selected { border-color: var(--primary); background: #f4f2ff; }
.choice-item input { accent-color: var(--primary); }

.ox-row { display: flex; gap: 12px; margin-bottom: 6px; }
.ox-btn {
  flex: 1; padding: 22px 0; border-radius: 14px; border: 1.5px solid var(--border);
  background: #fff; font-size: 26px; font-weight: 900; cursor: pointer; color: var(--text-mute);
}
.ox-btn.selected.o { border-color: var(--ok); color: var(--ok); background: #ecfbf3; }
.ox-btn.selected.x { border-color: var(--ng); color: var(--ng); background: #fdedef; }

.feedback-card { }
.feedback-banner {
  font-size: 17px; font-weight: 800; padding: 12px 14px; border-radius: 12px; margin-bottom: 10px;
}
.feedback-banner.ok { background: #ecfbf3; color: var(--ok); }
.feedback-banner.ng { background: #fdedef; color: var(--ng); }
.explain { font-size: 14.5px; line-height: 1.6; color: var(--text); background: #f8f7fc; padding: 12px 14px; border-radius: 12px; white-space: pre-wrap; }

.copy-box { margin-top: 14px; }
.copy-status { font-size: 13px; color: var(--text-mute); margin: 6px 0 10px; }
.copy-status.pass { color: var(--ok); font-weight: 700; }

.next-buttons { display: flex; flex-direction: column; gap: 8px; margin-top: 14px; }

/* -------- Result screen -------- */
.result-card { text-align: center; }
.result-stats { display: flex; justify-content: center; gap: 18px; margin: 16px 0; }
.stat { display: flex; flex-direction: column; }
.stat-num { font-size: 28px; font-weight: 900; }
.stat.ok .stat-num { color: var(--ok); }
.stat.ng .stat-num { color: var(--ng); }
.stat-label { font-size: 12px; color: var(--text-mute); }
.reward-box {
  margin: 14px 0; padding: 16px; border-radius: 14px; font-weight: 800; font-size: 16px;
}
.reward-box.win { background: #fff6e0; color: #b8860b; }
.reward-box.lose { background: #f4f2ff; color: var(--text-mute); font-weight: 600; font-size: 14px; }

/* -------- Admin -------- */
.admin-summary { display: flex; gap: 16px; margin: 10px 0 16px; flex-wrap: wrap; }
.admin-summary .stat-num { font-size: 20px; }
.session-row {
  border: 1.5px solid var(--border); border-radius: 12px; padding: 12px 14px; margin-bottom: 8px;
  font-size: 13.5px; display: flex; justify-content: space-between; align-items: center; gap: 8px;
}
.session-row .info { line-height: 1.5; }
.session-row .badge { font-weight: 800; font-size: 12px; padding: 3px 8px; border-radius: 999px; }
.badge.win { background: #fff6e0; color: #b8860b; }
.badge.claimed { background: #ecfbf3; color: var(--ok); }
.error { color: var(--ng); font-size: 13px; margin-top: 8px; }