:root {
  --brand: #C24A1F;
  --brand-soft: rgba(194, 74, 31, 0.13);
  --brand-faint: rgba(194, 74, 31, 0.12);
  --navy: #24334A;
  --navy-surface: #24334A;
  --bg: #F2F2F7;
  --card: #FFFFFF;
  --secondary: #6B7280;
  --success: #34C759;
  --danger: #FF3B30;
  --font: -apple-system, BlinkMacSystemFont, "SF Pro Display", "PingFang SC", "Helvetica Neue", Arial, sans-serif;
}

* { box-sizing: border-box; }

html, body {
  margin: 0;
  padding: 0;
  background: var(--bg);
  color: var(--navy);
  font-family: var(--font);
  -webkit-font-smoothing: antialiased;
}

button, input { font-family: inherit; }

a { color: var(--brand); text-decoration: none; }

/* 顶部品牌栏 */
.brand-bar {
  position: sticky;
  top: 0;
  z-index: 10;
  display: flex;
  align-items: center;
  min-height: 48px;
  padding: 0 16px;
  padding-top: env(safe-area-inset-top);
  background: rgba(255, 255, 255, 0.92);
  backdrop-filter: saturate(180%) blur(12px);
  -webkit-backdrop-filter: saturate(180%) blur(12px);
  border-bottom: 0.5px solid rgba(36, 51, 74, 0.12);
}
.brand-name {
  flex: 1;
  text-align: center;
  font-size: 17px;
  font-weight: 700;
  color: var(--navy);
}
.brand-back {
  min-width: 64px;
  min-height: 44px;
  display: inline-flex;
  align-items: center;
  font-size: 15px;
  color: var(--secondary);
}
.brand-spacer { min-width: 64px; }

.boot-hint { text-align: center; color: var(--secondary); padding: 80px 20px; }

.app-error {
  margin: 40px auto;
  max-width: 420px;
  background: var(--card);
  border-radius: 16px;
  padding: 24px;
  text-align: center;
  color: var(--secondary);
}
.app-error strong { color: var(--navy); font-size: 18px; }
.app-error .error-reload {
  display: inline-block;
  margin-top: 12px;
  min-height: 44px;
  line-height: 44px;
  padding: 0 24px;
  border-radius: 12px;
  background: var(--brand);
  color: #fff;
  font-weight: 700;
  font-size: 16px;
  text-decoration: none;
}

/* 主内容 */
#root {
  max-width: 640px;
  margin: 0 auto;
  padding: 20px 20px calc(20px + 84px + env(safe-area-inset-bottom));
}

/* 底部 Tab */
.tabbar {
  position: fixed;
  left: 0;
  right: 0;
  bottom: 0;
  z-index: 20;
  display: flex;
  justify-content: center;
  background: rgba(255, 255, 255, 0.94);
  backdrop-filter: saturate(180%) blur(12px);
  -webkit-backdrop-filter: saturate(180%) blur(12px);
  border-top: 0.5px solid rgba(36, 51, 74, 0.12);
  padding-bottom: env(safe-area-inset-bottom);
}
.tabbar a {
  flex: 0 1 213px;
  min-height: 52px;
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  gap: 3px;
  font-size: 11px;
  font-weight: 600;
  color: var(--secondary);
}
.tabbar a.active { color: var(--brand); }
.tab-ico { display: inline-flex; }
.tab-ico svg { width: 22px; height: 22px; }

/* 标题层级 */
.screen-title { font-size: 34px; font-weight: 700; margin: 8px 0 4px; }
.screen-sub { color: var(--secondary); font-size: 15px; margin: 0 0 18px; }
.page-title-2 { font-size: 22px; font-weight: 700; margin: 6px 0 4px; }
.kicker {
  font-size: 12px;
  font-weight: 700;
  letter-spacing: 1.2px;
  text-transform: uppercase;
  color: var(--brand);
  margin: 0 0 6px;
}
.section { margin-top: 26px; }
.section-title { font-size: 17px; font-weight: 700; margin: 0 0 10px; }

/* 卡片 */
.card {
  background: var(--card);
  border-radius: 16px;
  padding: 17px;
}
.card + .card { margin-top: 12px; }

.row-card {
  display: flex;
  align-items: center;
  gap: 14px;
  background: var(--card);
  border-radius: 16px;
  padding: 15px;
  min-height: 72px;
  color: inherit;
  width: 100%;
  text-align: left;
  border: 0;
  cursor: pointer;
}
.row-card + .row-card { margin-top: 12px; }
.row-card .row-ico {
  flex: 0 0 38px;
  width: 38px;
  height: 38px;
  display: inline-flex;
  align-items: center;
  justify-content: center;
  background: var(--brand-faint);
  border-radius: 11px;
  color: var(--brand);
}
.row-card .row-main { flex: 1; min-width: 0; }
.row-card .row-main > * { display: block; }
.row-card .row-title { font-size: 16px; font-weight: 700; color: var(--navy); }
.row-card .row-sub { font-size: 13px; color: var(--secondary); margin-top: 3px; }
.row-card .chev { color: var(--secondary); flex: 0 0 auto; }

/* 阶段卡（藏青大卡） */
.stage-hero {
  background: var(--navy-surface);
  color: #fff;
  border-radius: 22px;
  padding: 22px;
  margin: 14px 0 18px;
}
.stage-hero .hero-label { font-size: 14px; font-weight: 500; opacity: 0.75; }
.stage-hero .hero-name { font-size: 34px; font-weight: 700; margin-top: 6px; }
.stage-hero button {
  margin-top: 14px;
  min-height: 44px;
  padding: 0 16px;
  border: 0;
  border-radius: 12px;
  background: rgba(255, 255, 255, 0.16);
  color: #fff;
  font-weight: 600;
  font-size: 14px;
}

/* 进度三格 */
.metric-row {
  display: flex;
  background: var(--card);
  border-radius: 18px;
  padding: 20px 0;
  margin-bottom: 18px;
}
.metric { flex: 1; text-align: center; }
.metric + .metric { border-left: 0.5px solid rgba(36, 51, 74, 0.15); }
.metric .metric-value { font-size: 17px; font-weight: 700; }
.metric .metric-label { font-size: 12px; color: var(--secondary); margin-top: 5px; }

/* 按钮 */
.btn-primary {
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 8px;
  width: 100%;
  min-height: 50px;
  border: 0;
  border-radius: 12px;
  background: var(--brand);
  color: #fff;
  font-size: 17px;
  font-weight: 700;
  cursor: pointer;
}
.btn-primary:disabled { opacity: 0.45; cursor: default; }
.btn-secondary {
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 8px;
  width: 100%;
  min-height: 50px;
  border-radius: 12px;
  background: transparent;
  border: 1.5px solid var(--navy);
  color: var(--navy);
  font-size: 17px;
  font-weight: 600;
  cursor: pointer;
}
.btn-stack > * + * { margin-top: 12px; }

/* 表单 */
.field-input {
  width: 100%;
  min-height: 50px;
  border: 1px solid rgba(36, 51, 74, 0.2);
  border-radius: 12px;
  background: var(--card);
  padding: 0 14px;
  font-size: 17px;
  color: var(--navy);
}

/* 阶段选择 */
.stage-grid { display: grid; grid-template-columns: 1fr 1fr; gap: 12px; }
.stage-cell {
  min-height: 64px;
  background: var(--card);
  border: 0;
  border-radius: 16px;
  padding: 14px;
  text-align: left;
  cursor: pointer;
}
.stage-cell .stage-order { font-size: 12px; color: var(--brand); font-weight: 700; }
.stage-cell .stage-name { font-size: 16px; font-weight: 700; color: var(--navy); margin-top: 4px; }

/* 课程行 */
.course-ico { flex: 0 0 34px; color: var(--brand); display: inline-flex; }
.course-ico.done { color: var(--success); }
.course-status { font-size: 12px; font-weight: 500; color: var(--secondary); margin-top: 5px; }
.course-status.done { color: var(--success); }

/* 课程详情 */
.detail-head h1 { font-size: 34px; font-weight: 700; margin: 0 0 10px; }
.detail-summary { color: var(--secondary); margin: 0 0 10px; line-height: 1.6; }
.detail-meta { display: inline-flex; align-items: center; gap: 6px; font-size: 12px; color: var(--secondary); }
.dot-list { list-style: none; margin: 12px 0 0; padding: 0; }
.dot-list li { position: relative; padding-left: 18px; margin: 10px 0; line-height: 1.55; }
.dot-list li::before {
  content: "";
  position: absolute;
  left: 2px;
  top: 0.62em;
  width: 6px;
  height: 6px;
  border-radius: 50%;
  background: var(--brand);
}
.block-title { display: flex; align-items: center; gap: 8px; font-size: 16px; font-weight: 700; margin: 0; }
.block-title svg { color: var(--brand); }

.md-body h3 { font-size: 20px; font-weight: 700; margin: 22px 0 10px; }
.md-body p { line-height: 1.8; margin: 14px 0; }
.md-body ul { margin: 14px 0; padding-left: 22px; }
.md-body li { line-height: 1.8; margin: 6px 0; }

.refs a { display: inline-flex; align-items: center; gap: 6px; font-size: 14px; min-height: 44px; }
.refs .ref-text { font-size: 14px; color: var(--secondary); }
.refs > * + * { margin-top: 4px; }

.hr { border: 0; border-top: 0.5px solid rgba(36, 51, 74, 0.15); margin: 26px 0; }
.fine-note { font-size: 12px; color: var(--secondary); margin-top: 8px; }
.inline-ok { display: inline-flex; align-items: center; gap: 8px; color: var(--success); font-weight: 700; }

/* 答题 */
.quiz-top {
  display: flex;
  align-items: center;
  justify-content: space-between;
  margin-bottom: 14px;
}
.quiz-pos { font-size: 15px; font-weight: 600; color: var(--brand); }
.quiz-type { font-size: 12px; font-weight: 500; color: var(--secondary); }
.quiz-timer {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  font-size: 17px;
  font-weight: 700;
  font-variant-numeric: tabular-nums;
}
.quiz-timer.danger { color: var(--danger); }
.quiz-stem { font-size: 20px; font-weight: 700; line-height: 1.5; margin: 0 0 6px; }
.quiz-point { font-size: 12px; color: var(--secondary); margin: 0 0 14px; }
.multi-hint { font-size: 13px; color: var(--secondary); margin: 0 0 10px; }

.option-card {
  display: flex;
  align-items: center;
  gap: 12px;
  width: 100%;
  padding: 15px;
  min-height: 52px;
  border: 0;
  border-radius: 13px;
  background: var(--bg);
  color: var(--navy);
  font-size: 16px;
  text-align: left;
  line-height: 1.5;
  cursor: pointer;
}
.option-card + .option-card { margin-top: 10px; }
.option-card .opt-ico { flex: 0 0 auto; color: var(--secondary); display: inline-flex; }
.option-card.selected { background: var(--brand-soft); box-shadow: inset 0 0 0 1.5px var(--brand); }
.option-card.selected .opt-ico { color: var(--brand); }

.quiz-nav { display: flex; align-items: center; gap: 12px; margin-top: 22px; }
.quiz-nav .btn-ghost {
  min-height: 44px;
  padding: 0 18px;
  border: 0;
  background: transparent;
  color: var(--navy);
  font-size: 15px;
  font-weight: 600;
  cursor: pointer;
}
.quiz-nav .btn-ghost:disabled { opacity: 0.35; cursor: default; }
.quiz-nav .spacer { flex: 1; }
.quiz-nav .btn-primary { width: auto; padding: 0 22px; min-height: 46px; }

/* 结果 */
.result-hero .result-big {
  font-size: 40px;
  font-weight: 800;
  font-variant-numeric: tabular-nums;
  color: var(--navy);
  margin: 2px 0 6px;
}
.result-hero .result-big.brand { color: var(--brand); }
.result-note { color: var(--secondary); margin: 0 0 16px; }
.result-icon { display: inline-flex; margin-bottom: 10px; }
.result-icon.pass { color: var(--brand); }
.result-icon.fail { color: var(--navy); }
.result-icon svg { width: 52px; height: 52px; }

.result-card { background: var(--card); border-radius: 16px; padding: 17px; }
.result-card + .result-card { margin-top: 12px; }
.result-status { display: inline-flex; align-items: center; gap: 6px; font-size: 12px; font-weight: 700; }
.result-status.ok { color: var(--success); }
.result-status.bad { color: var(--danger); }
.result-stem { font-size: 16px; font-weight: 700; margin: 8px 0; line-height: 1.5; }
.result-answer { font-size: 14px; margin: 0 0 6px; }
.result-expl { font-size: 14px; color: var(--secondary); line-height: 1.7; margin: 0 0 8px; }

/* 考试 */
.exam-info {
  background: var(--card);
  border-radius: 18px;
  padding: 20px;
  margin: 18px 0;
}
.exam-info .info-line {
  display: flex;
  align-items: center;
  gap: 10px;
  font-weight: 500;
  min-height: 30px;
}
.exam-info .info-line + .info-line { margin-top: 10px; }
.exam-info svg { color: var(--brand); flex: 0 0 auto; }
.exam-hero-icon { color: var(--brand); display: inline-flex; margin: 6px 0 12px; }
.exam-hero-icon svg { width: 48px; height: 48px; }

/* 证书 */
.cert-card {
  background: #FCF9F0;
  border: 2px solid var(--navy);
  outline: 1px solid rgba(194, 74, 31, 0.45);
  outline-offset: 5px;
  border-radius: 18px;
  padding: 30px 24px;
  text-align: center;
  margin: 20px 0;
}
.cert-brand { font-size: 20px; font-weight: 800; letter-spacing: 6px; color: var(--navy); }
.cert-icon { color: var(--brand); display: inline-flex; margin: 16px 0 8px; }
.cert-icon svg { width: 64px; height: 64px; }
.cert-title { font-size: 26px; font-weight: 700; color: var(--navy); }
.cert-en { font-size: 11px; font-weight: 600; letter-spacing: 4px; color: var(--brand); margin-top: 4px; }
.cert-divider { width: 90px; height: 3px; background: var(--brand); margin: 14px auto; }
.cert-to { color: var(--secondary); font-size: 14px; }
.cert-name { font-size: 28px; font-weight: 700; margin: 6px 0; }
.cert-line { font-size: 15px; margin: 4px 0; }
.cert-score { font-size: 20px; font-weight: 800; color: var(--brand); font-variant-numeric: tabular-nums; margin-top: 8px; }
.cert-disclaimer { font-size: 12px; color: var(--secondary); margin-top: 18px; line-height: 1.6; }
.cert-meta {
  display: flex;
  justify-content: space-between;
  gap: 10px;
  flex-wrap: wrap;
  font-size: 12px;
  font-weight: 500;
  margin-top: 10px;
}
.cert-row { display: flex; align-items: center; gap: 14px; }
.cert-row .medal-ico { color: var(--brand); flex: 0 0 34px; display: inline-flex; }

.empty-hint { color: var(--secondary); text-align: center; padding: 40px 20px; }

/* 工具类（替代内联样式，保持 CSP style-src 'self'） */
.mt8 { margin-top: 8px; }
.mt18 { margin-top: 18px; }
.fs14-strong { font-size: 14px; font-weight: 600; }
.quiz-type.flush { margin: 0 0 12px; }
.result-score {
  font-size: 40px;
  font-weight: 800;
  font-variant-numeric: tabular-nums;
  color: var(--brand);
  margin: 0 0 8px;
}
[hidden] { display: none !important; }