:root {
  --eh-ink: #17262d;
  --eh-muted: #62727a;
  --eh-paper: #f4f7f5;
  --eh-panel: #ffffff;
  --eh-panel-2: #f8fbf9;
  --eh-line: #dce5e0;
  --eh-line-strong: #c4d4cd;
  --eh-navy: #173944;
  --eh-navy-2: #21505c;
  --eh-teal: #0d766d;
  --eh-teal-dark: #075c56;
  --eh-teal-soft: #e3f2ee;
  --eh-amber: #b97b18;
  --eh-amber-soft: #fff2d8;
  --eh-red: #a8473c;
  --eh-red-soft: #fbe9e6;
  --eh-green: #34735c;
  --eh-green-soft: #e8f3ed;
  --eh-blue: #326681;
  --eh-blue-soft: #e8f0f5;
  --eh-shadow: 0 16px 40px rgba(25, 54, 61, .08);
  --eh-radius: 8px;
  --eh-header: 68px;
  --eh-sidebar: 286px;
  --eh-sans: "PingFang SC", "Hiragino Sans GB", "Microsoft YaHei", "Noto Sans SC", -apple-system, BlinkMacSystemFont, "Segoe UI", sans-serif;
  --eh-mono: "SF Mono", "JetBrains Mono", "Cascadia Mono", ui-monospace, Menlo, Consolas, monospace;
}
[data-theme="dark"] {
  --eh-ink: #e9f0ed;
  --eh-muted: #aabbb5;
  --eh-paper: #101719;
  --eh-panel: #182226;
  --eh-panel-2: #202c30;
  --eh-line: rgba(226, 240, 234, .14);
  --eh-line-strong: rgba(226, 240, 234, .25);
  --eh-navy: #0e2c35;
  --eh-navy-2: #174754;
  --eh-teal: #52c7b9;
  --eh-teal-dark: #8ee4d8;
  --eh-teal-soft: rgba(82,199,185,.14);
  --eh-amber: #e7b85d;
  --eh-amber-soft: rgba(231,184,93,.15);
  --eh-red: #e98e82;
  --eh-red-soft: rgba(233,142,130,.14);
  --eh-green: #73c495;
  --eh-green-soft: rgba(115,196,149,.14);
  --eh-blue: #80b7d2;
  --eh-blue-soft: rgba(128,183,210,.14);
  --eh-shadow: 0 18px 46px rgba(0, 0, 0, .32);
}
* { box-sizing: border-box; }
html { scroll-behavior: smooth; }
body {
  margin: 0;
  color: var(--eh-ink);
  background: var(--eh-paper);
  font-family: var(--eh-sans);
  line-height: 1.65;
  font-size: 14px;
  -webkit-font-smoothing: antialiased;
}
body.modal-open { overflow: hidden; }
a { color: inherit; }
button, input { font: inherit; }
button { cursor: pointer; }
button:disabled { cursor: not-allowed; opacity: .68; }
.hidden { display: none !important; }
.eh-mono { font-family: var(--eh-mono); }

/* 顶栏 */
.exam-header {
  position: sticky;
  top: 0;
  z-index: 50;
  min-height: var(--eh-header);
  display: flex;
  align-items: center;
  gap: 18px;
  padding: 0 24px;
  color: #f7fbf9;
  background: var(--eh-navy);
  border-bottom: 1px solid rgba(255,255,255,.12);
}
.exam-brand { display: flex; align-items: center; gap: 11px; min-width: 270px; text-decoration: none; }
.exam-brand-mark { width: 38px; height: 38px; display: grid; place-items: center; flex: none; border-radius: 50%; color: var(--eh-navy); background: #f1c96f; font: 700 11px var(--eh-mono); }
.exam-brand-copy { display: grid; min-width: 0; line-height: 1.18; }
.exam-brand-copy b { font-size: 14px; white-space: nowrap; overflow: hidden; text-overflow: ellipsis; }
.exam-brand-copy span { margin-top: 4px; color: #bcd0cb; font-size: 10px; }
.exam-search { position: relative; flex: 1; max-width: 600px; }
.exam-search input { width: 100%; height: 38px; padding: 0 14px; color: #f7fbf9; background: rgba(255,255,255,.1); border: 1px solid rgba(255,255,255,.18); border-radius: 6px; outline: none; }
.exam-search input::placeholder { color: #bcd0cb; }
.exam-search input:focus { border-color: #f1c96f; box-shadow: 0 0 0 3px rgba(241,201,111,.14); }
.exam-search-results { position: absolute; top: 44px; left: 0; right: 0; max-height: 430px; overflow: auto; display: none; color: var(--eh-ink); background: var(--eh-panel); border: 1px solid var(--eh-line); border-radius: 7px; box-shadow: var(--eh-shadow); }
.exam-search-results.open { display: block; }
.exam-search-item { width: 100%; display: grid; gap: 2px; padding: 10px 13px; text-align: left; color: var(--eh-ink); background: var(--eh-panel); border: 0; border-bottom: 1px solid var(--eh-line); }
.exam-search-item:hover { background: var(--eh-teal-soft); }
.exam-search-item small { color: var(--eh-muted); font-size: 10px; }
.exam-actions { margin-left: auto; display: flex; align-items: center; gap: 7px; }
.exam-action-btn, .exam-back-link { min-height: 36px; display: inline-flex; align-items: center; justify-content: center; gap: 6px; padding: 0 11px; border-radius: 6px; white-space: nowrap; font-size: 11px; text-decoration: none; }
.exam-action-btn { color: #dceae7; background: transparent; border: 1px solid rgba(255,255,255,.21); }
.exam-action-btn:hover, .exam-back-link:hover { color: #fff; border-color: #f1c96f; }
.exam-action-btn.primary { color: var(--eh-navy); background: #f1c96f; border-color: #f1c96f; font-weight: 700; }
.exam-back-link { color: #dceae7; border: 1px solid rgba(255,255,255,.21); }

/* 主体 */
.exam-shell { min-height: calc(100vh - var(--eh-header)); display: grid; grid-template-columns: var(--eh-sidebar) minmax(0, 1fr); }
.exam-sidebar { position: sticky; top: var(--eh-header); align-self: start; height: calc(100vh - var(--eh-header)); overflow: auto; padding: 20px 14px 28px; background: var(--eh-panel); border-right: 1px solid var(--eh-line); }
.exam-sidebar-head { padding: 0 8px 13px; }
.exam-sidebar-head span { color: var(--eh-teal); font: 600 10px var(--eh-mono); letter-spacing: .04em; }
.exam-sidebar-head h2 { margin: 4px 0 4px; font-size: 16px; line-height: 1.35; }
.exam-sidebar-head p { margin: 0; color: var(--eh-muted); font-size: 10.5px; line-height: 1.55; }
.exam-track-list { display: grid; gap: 5px; }
.exam-track-btn { width: 100%; min-height: 64px; display: grid; grid-template-columns: 34px minmax(0,1fr) auto; align-items: center; gap: 9px; padding: 9px; text-align: left; color: var(--eh-ink); background: transparent; border: 1px solid transparent; border-radius: 6px; }
.exam-track-btn:hover { background: var(--eh-panel-2); }
.exam-track-btn.active { background: var(--eh-teal-soft); border-color: color-mix(in srgb, var(--eh-teal) 35%, transparent); }
.exam-track-index { width: 32px; height: 32px; display: grid; place-items: center; color: var(--eh-teal); background: var(--eh-panel-2); border-radius: 50%; font: 600 10px var(--eh-mono); }
.exam-track-btn.active .exam-track-index { color: var(--eh-navy); background: var(--eh-teal); }
.exam-track-copy { min-width: 0; display: grid; line-height: 1.25; }
.exam-track-copy b { font-size: 11px; overflow: hidden; text-overflow: ellipsis; white-space: nowrap; }
.exam-track-copy span { margin-top: 4px; color: var(--eh-muted); font-size: 9px; overflow: hidden; text-overflow: ellipsis; white-space: nowrap; }
.exam-track-score { color: var(--eh-muted); font: 500 9px var(--eh-mono); }
.exam-progress-card { margin: 18px 8px 0; padding: 14px; color: #dceae7; background: var(--eh-navy); border-radius: 7px; }
.exam-progress-card strong { display: flex; justify-content: space-between; gap: 8px; color: #fff; font-size: 12px; }
.exam-progress-meter { height: 7px; margin: 11px 0 7px; overflow: hidden; background: rgba(255,255,255,.16); border-radius: 9px; }
.exam-progress-meter span { display: block; width: 0; height: 100%; background: #f1c96f; transition: width .25s ease; }
.exam-progress-card p { margin: 0; color: #bcd0cb; font-size: 9px; }
.exam-sidebar-note { margin: 14px 8px 0; padding: 11px 12px; color: var(--eh-muted); background: var(--eh-panel-2); border: 1px solid var(--eh-line); border-radius: 6px; font-size: 10px; line-height: 1.6; }

.exam-workspace { min-width: 0; padding: 28px 34px 78px; }
.exam-workspace-inner { width: min(1180px, 100%); margin: 0 auto; }
.exam-loading, .exam-error { min-height: 62vh; display: grid; place-items: center; text-align: center; }
.exam-loading-card, .exam-error-card { max-width: 560px; padding: 30px; color: var(--eh-ink); background: var(--eh-panel); border: 1px solid var(--eh-line); border-radius: var(--eh-radius); box-shadow: var(--eh-shadow); }
.exam-loading-card h1, .exam-error-card h1 { margin: 0 0 8px; font-size: 22px; }
.exam-loading-card p, .exam-error-card p { margin: 0; color: var(--eh-muted); font-size: 12px; }
.exam-spinner { width: 30px; height: 30px; margin: 0 auto 14px; border: 3px solid var(--eh-teal-soft); border-top-color: var(--eh-teal); border-radius: 50%; animation: eh-spin .8s linear infinite; }
@keyframes eh-spin { to { transform: rotate(360deg); } }

.exam-hero { display: grid; grid-template-columns: minmax(0,1fr) auto; gap: 22px; align-items: end; padding: 24px; background: var(--eh-panel); border: 1px solid var(--eh-line); border-top: 4px solid var(--eh-teal); border-radius: var(--eh-radius); box-shadow: 0 8px 24px rgba(25,54,61,.04); }
.exam-kicker { color: var(--eh-teal); font: 600 10px var(--eh-mono); letter-spacing: .08em; text-transform: uppercase; }
.exam-hero h1 { margin: 8px 0 7px; font-size: clamp(25px, 3vw, 38px); line-height: 1.18; letter-spacing: -.02em; }
.exam-hero p { max-width: 790px; margin: 0; color: var(--eh-muted); font-size: 13px; }
.exam-meta-grid { display: grid; grid-template-columns: repeat(3, minmax(78px, 1fr)); gap: 8px; }
.exam-metric { min-width: 80px; padding: 10px; text-align: center; background: var(--eh-panel-2); border: 1px solid var(--eh-line); border-radius: 6px; }
.exam-metric b { display: block; color: var(--eh-teal); font: 600 17px var(--eh-mono); }
.exam-metric span { color: var(--eh-muted); font-size: 9px; }
.exam-notice { margin-top: 14px; padding: 13px 15px; color: var(--eh-ink); background: var(--eh-amber-soft); border: 1px solid color-mix(in srgb, var(--eh-amber) 35%, transparent); border-left: 3px solid var(--eh-amber); border-radius: 6px; font-size: 11px; line-height: 1.7; }
.exam-notice strong { color: var(--eh-amber); }
.exam-link-row { display: flex; flex-wrap: wrap; gap: 7px; margin-top: 10px; }
.exam-source-link { display: inline-flex; align-items: center; gap: 4px; padding: 4px 8px; color: var(--eh-teal); background: var(--eh-panel); border: 1px solid var(--eh-line); border-radius: 4px; font-size: 10px; text-decoration: none; }
.exam-source-link:hover { border-color: var(--eh-teal); background: var(--eh-teal-soft); }

.exam-unit-nav { margin-top: 16px; padding: 14px; background: var(--eh-panel); border: 1px solid var(--eh-line); border-radius: var(--eh-radius); }
.exam-unit-nav-head { display: flex; justify-content: space-between; align-items: center; gap: 12px; padding: 0 3px 10px; }
.exam-unit-nav-head b { font-size: 12px; }
.exam-unit-nav-head span { color: var(--eh-muted); font-size: 10px; }
.exam-unit-tabs { display: grid; grid-auto-flow: column; grid-auto-columns: minmax(178px, 1fr); gap: 7px; overflow-x: auto; padding-bottom: 4px; }
.exam-unit-tab { min-height: 66px; padding: 10px; display: grid; grid-template-columns: 25px minmax(0,1fr); gap: 8px; align-items: start; text-align: left; color: var(--eh-ink); background: var(--eh-panel-2); border: 1px solid var(--eh-line); border-radius: 6px; }
.exam-unit-tab:hover { border-color: color-mix(in srgb, var(--eh-teal) 50%, var(--eh-line)); }
.exam-unit-tab.active { color: #fff; background: var(--eh-teal); border-color: var(--eh-teal); }
.exam-unit-number { width: 24px; height: 24px; display: grid; place-items: center; border: 1px solid currentColor; border-radius: 50%; font: 500 9px var(--eh-mono); }
.exam-unit-copy { min-width: 0; display: grid; line-height: 1.25; }
.exam-unit-copy b { font-size: 10px; white-space: normal; }
.exam-unit-copy span { margin-top: 5px; color: var(--eh-muted); font-size: 8.5px; }
.exam-unit-tab.active .exam-unit-copy span { color: #d6ebe6; }
.exam-unit-done { color: var(--eh-green); font-size: 12px; }

.exam-unit-heading { margin-top: 25px; display: grid; grid-template-columns: minmax(0,1fr) auto; gap: 20px; align-items: end; }
.exam-unit-heading h2 { margin: 5px 0 4px; font-size: 25px; line-height: 1.25; }
.exam-unit-heading p { max-width: 800px; margin: 0; color: var(--eh-muted); font-size: 12px; }
.exam-unit-time { padding: 7px 10px; color: var(--eh-teal); background: var(--eh-teal-soft); border-radius: 5px; font: 500 10px var(--eh-mono); white-space: nowrap; }
.exam-section-title { margin: 26px 0 12px; display: flex; justify-content: space-between; align-items: end; gap: 16px; }
.exam-section-title h3 { margin: 0; font-size: 18px; }
.exam-section-title span { color: var(--eh-muted); font-size: 10px; }
.exam-concept-stack { display: grid; gap: 11px; }
.exam-concept-card { overflow: hidden; background: var(--eh-panel); border: 1px solid var(--eh-line); border-radius: var(--eh-radius); }
.exam-concept-head { padding: 15px 17px 12px; display: grid; grid-template-columns: 34px minmax(0,1fr) auto; align-items: start; gap: 11px; border-bottom: 1px solid var(--eh-line); }
.exam-concept-num { width: 32px; height: 32px; display: grid; place-items: center; color: #fff; background: var(--eh-navy); border-radius: 50%; font: 500 10px var(--eh-mono); }
.exam-concept-head h4 { margin: 0; font-size: 15px; line-height: 1.35; }
.exam-concept-head h4 span { display: block; margin-top: 2px; color: var(--eh-muted); font-size: 10px; font-weight: 500; }
.exam-master-btn { min-width: 92px; min-height: 31px; padding: 0 9px; color: var(--eh-teal); background: var(--eh-panel); border: 1px solid color-mix(in srgb, var(--eh-teal) 55%, var(--eh-line)); border-radius: 5px; font-size: 10px; }
.exam-master-btn.done { color: #fff; background: var(--eh-green); border-color: var(--eh-green); }
.exam-concept-body { padding: 16px 17px 17px; }
.exam-concept-explain { margin: 0; font-size: 13px; line-height: 1.75; }
.exam-concept-tools { margin-top: 13px; display: grid; grid-template-columns: repeat(3, minmax(0,1fr)); gap: 8px; }
.exam-tool-box { min-width: 0; padding: 10px; border-radius: 5px; }
.exam-tool-box.formula { background: var(--eh-blue-soft); border: 1px solid color-mix(in srgb, var(--eh-blue) 25%, var(--eh-line)); }
.exam-tool-box.intuition { background: var(--eh-amber-soft); border: 1px solid color-mix(in srgb, var(--eh-amber) 28%, var(--eh-line)); }
.exam-tool-box.signal { background: var(--eh-teal-soft); border: 1px solid color-mix(in srgb, var(--eh-teal) 25%, var(--eh-line)); }
.exam-tool-box b { display: block; margin-bottom: 5px; color: var(--eh-muted); font: 600 9px var(--eh-mono); letter-spacing: .04em; }
.exam-tool-box span, .exam-tool-box code { display: block; color: var(--eh-ink); font-size: 10px; line-height: 1.55; white-space: normal; word-break: break-word; }

.exam-practice { margin-top: 14px; padding-top: 12px; border-top: 1px dashed var(--eh-line); }
.exam-practice-head { display: flex; justify-content: space-between; align-items: center; gap: 10px; margin-bottom: 9px; }
.exam-practice-head b { font-size: 11px; }
.exam-question-type { padding: 3px 6px; color: var(--eh-blue); background: var(--eh-blue-soft); border-radius: 3px; font-size: 8px; }
.exam-question { margin: 0 0 9px; font-size: 12px; font-weight: 600; line-height: 1.55; }
.exam-options { display: grid; gap: 6px; }
.exam-option { width: 100%; min-height: 39px; display: grid; grid-template-columns: 25px 1fr; gap: 8px; align-items: center; padding: 7px 9px; text-align: left; color: var(--eh-ink); background: var(--eh-panel-2); border: 1px solid var(--eh-line); border-radius: 5px; font-size: 11px; }
.exam-option:hover:not(:disabled) { border-color: color-mix(in srgb, var(--eh-teal) 65%, var(--eh-line)); background: var(--eh-teal-soft); }
.exam-option.selected { border-color: var(--eh-teal); background: var(--eh-teal-soft); }
.exam-option.correct { color: var(--eh-green); background: var(--eh-green-soft); border-color: color-mix(in srgb, var(--eh-green) 65%, var(--eh-line)); }
.exam-option.wrong { color: var(--eh-red); background: var(--eh-red-soft); border-color: color-mix(in srgb, var(--eh-red) 65%, var(--eh-line)); }
.exam-option.dimmed { opacity: .58; }
.exam-option-letter { width: 23px; height: 23px; display: grid; place-items: center; border: 1px solid var(--eh-line-strong); border-radius: 50%; font: 600 9px var(--eh-mono); }
.exam-feedback { margin-top: 10px; padding: 11px 12px; display: none; border-radius: 5px; font-size: 10.5px; line-height: 1.65; }
.exam-feedback.show { display: block; }
.exam-feedback.correct { color: var(--eh-green); background: var(--eh-green-soft); border-left: 3px solid var(--eh-green); }
.exam-feedback.wrong { color: var(--eh-red); background: var(--eh-red-soft); border-left: 3px solid var(--eh-red); }
.exam-feedback strong { display: block; margin-bottom: 3px; }
.exam-retry { margin-top: 8px; padding: 5px 8px; color: inherit; background: transparent; border: 1px solid currentColor; border-radius: 4px; font-size: 9px; }
.exam-unit-practice { margin-top: 15px; }
.exam-unit-practice:empty { display: none; }
.exam-unit-practice-head { display: flex; justify-content: space-between; align-items: center; gap: 16px; padding: 17px; background: var(--eh-panel); border: 1px solid var(--eh-line); border-left: 4px solid var(--eh-amber); border-radius: var(--eh-radius); }
.exam-unit-practice-head h3 { margin: 4px 0 2px; font-size: 16px; }
.exam-unit-practice-head p { margin: 0; color: var(--eh-muted); font-size: 10.5px; }
.exam-unit-practice-actions { display: flex; align-items: center; gap: 10px; flex: none; }
.exam-unit-practice-actions span { color: var(--eh-muted); font: 600 10px var(--eh-mono); }
.exam-unit-practice-actions button { min-height: 35px; padding: 0 13px; color: #fff; background: var(--eh-navy); border: 0; border-radius: 5px; font-size: 10px; font-weight: 700; }
.exam-unit-practice-actions button:hover { background: var(--eh-navy-2); }

.exam-lower-grid { margin-top: 15px; display: grid; grid-template-columns: 1.15fr .85fr; gap: 14px; }
.exam-lower-card { padding: 17px; background: var(--eh-panel); border: 1px solid var(--eh-line); border-radius: var(--eh-radius); }
.exam-lower-card h3 { margin: 0 0 6px; font-size: 15px; }
.exam-lower-card > p { margin: 0 0 12px; color: var(--eh-muted); font-size: 10px; }
.exam-check-list { display: grid; gap: 8px; }
.exam-check { display: flex; gap: 8px; align-items: flex-start; color: var(--eh-ink); font-size: 11px; }
.exam-check input { margin-top: 4px; accent-color: var(--eh-teal); }
.exam-memory { color: #6d4c0d; background: var(--eh-amber-soft); border-color: color-mix(in srgb, var(--eh-amber) 35%, var(--eh-line)); }
[data-theme="dark"] .exam-memory { color: #f0d79d; }
.exam-memory p { margin: 0; font-size: 11px; line-height: 1.7; }
.exam-complete { margin-top: 14px; display: flex; justify-content: space-between; align-items: center; gap: 10px; padding: 14px 16px; color: #e6f1ef; background: var(--eh-navy); border-radius: var(--eh-radius); }
.exam-complete p { margin: 0; color: #bcd0cb; font-size: 10px; }
.exam-complete strong { color: #fff; font-size: 13px; }
.exam-complete-btn { padding: 7px 10px; color: var(--eh-navy); background: #f1c96f; border: 0; border-radius: 5px; font-size: 10px; font-weight: 700; }
.exam-complete-btn.done { color: #fff; background: var(--eh-green); }
.exam-unit-pager { margin-top: 14px; display: flex; justify-content: space-between; gap: 10px; }
.exam-unit-pager button { min-height: 40px; max-width: 48%; padding: 8px 12px; color: var(--eh-teal); background: var(--eh-panel); border: 1px solid color-mix(in srgb, var(--eh-teal) 55%, var(--eh-line)); border-radius: 5px; font-size: 10px; }
.exam-unit-pager button:disabled { visibility: hidden; }
.exam-source-note { margin-top: 14px; color: var(--eh-muted); font-size: 10px; line-height: 1.65; }
.exam-source-note a { color: var(--eh-teal); }
.exam-footer { margin-top: 36px; padding: 16px 0; display: flex; justify-content: space-between; gap: 16px; color: var(--eh-muted); border-top: 1px solid var(--eh-line); font-size: 9.5px; }
.exam-footer a { color: var(--eh-teal); }

/* 模态层 */
.exam-modal { position: fixed; inset: 0; z-index: 90; display: flex; align-items: flex-start; justify-content: center; padding: 30px 16px 60px; background: rgba(10,24,28,.58); overflow-y: auto; }
.exam-modal-panel { width: min(800px, 100%); padding: 22px 24px; color: var(--eh-ink); background: var(--eh-panel); border-radius: 10px; box-shadow: var(--eh-shadow); }
.exam-modal-head { display: flex; align-items: center; justify-content: space-between; gap: 12px; margin-bottom: 16px; padding-bottom: 13px; border-bottom: 1px solid var(--eh-line); }
.exam-modal-head h2 { margin: 0; font-size: 18px; }
.exam-modal-close { width: 32px; height: 32px; color: var(--eh-muted); background: var(--eh-panel); border: 1px solid var(--eh-line); border-radius: 6px; font-size: 16px; line-height: 1; }
.exam-modal-close:hover { color: var(--eh-ink); border-color: var(--eh-line-strong); }
.exam-bank-summary { display: flex; justify-content: space-between; align-items: center; gap: 12px; margin-bottom: 13px; padding: 12px 14px; color: #dceae7; background: var(--eh-navy); border-radius: 7px; }
.exam-bank-summary strong { color: #fff; font-size: 12px; }
.exam-bank-summary span { color: #bcd0cb; font-size: 10px; }
.exam-mock-list { display: grid; gap: 11px; }
.exam-mock-card { display: flex; flex-direction: column; gap: 7px; padding: 15px 17px; background: var(--eh-panel-2); border: 1px solid var(--eh-line); border-radius: 8px; }
.exam-mock-card:hover { border-color: var(--eh-teal); }
.exam-mock-head { display: flex; justify-content: space-between; align-items: center; gap: 10px; flex-wrap: wrap; }
.exam-mock-badge { display: inline-flex; padding: 3px 9px; color: var(--eh-teal); background: var(--eh-teal-soft); border-radius: 5px; font-size: 10px; font-weight: 700; }
.exam-mock-meta { color: var(--eh-muted); font-size: 10px; }
.exam-mock-title { font-size: 15px; font-weight: 700; }
.exam-mock-sub { color: var(--eh-muted); font-size: 11px; }
.exam-start-btn { align-self: flex-start; margin-top: 3px; padding: 8px 14px; color: #fff; background: var(--eh-navy); border: 0; border-radius: 5px; font-size: 11px; font-weight: 700; }
.exam-start-btn:hover { background: var(--eh-navy-2); }
.exam-random-entry { margin-top: 13px; padding-top: 13px; border-top: 1px dashed var(--eh-line); }
.exam-random-entry button { padding: 8px 14px; color: var(--eh-teal); background: transparent; border: 1px solid var(--eh-teal); border-radius: 5px; font-size: 11px; }
.exam-random-entry button:hover { background: var(--eh-teal-soft); }
.exam-exam-meta { display: flex; gap: 16px; flex-wrap: wrap; align-items: center; margin-bottom: 14px; color: var(--eh-muted); font-size: 11px; }
.exam-timer { color: var(--eh-navy); font: 700 23px var(--eh-mono); }
[data-theme="dark"] .exam-timer { color: var(--eh-teal); }
.exam-exam-q { margin-bottom: 10px; padding: 14px; background: var(--eh-panel-2); border: 1px solid var(--eh-line); border-radius: 8px; }
.exam-exam-q-num { margin-bottom: 6px; color: var(--eh-muted); font-size: 10px; }
.exam-exam-q-text { margin-bottom: 10px; font-size: 13px; font-weight: 600; line-height: 1.55; }
.exam-exam-option { display: block; width: 100%; margin: 5px 0; padding: 9px 11px; text-align: left; color: var(--eh-ink); background: var(--eh-panel); border: 1px solid var(--eh-line); border-radius: 6px; font-size: 11px; }
.exam-exam-option:hover { border-color: var(--eh-teal); }
.exam-exam-option.chosen { border-color: var(--eh-teal); background: var(--eh-teal-soft); }
.exam-actions-row { display: flex; justify-content: space-between; align-items: center; gap: 10px; flex-wrap: wrap; margin-top: 18px; }
.exam-submit-btn { padding: 10px 18px; color: #fff; background: var(--eh-navy); border: 0; border-radius: 6px; font-size: 12px; font-weight: 700; }
.exam-submit-btn:hover { background: var(--eh-navy-2); }
.exam-result { padding: 8px 0 4px; text-align: center; }
.exam-score { color: var(--eh-navy); font: 700 42px var(--eh-mono); }
[data-theme="dark"] .exam-score { color: var(--eh-teal); }
.exam-score-note { color: var(--eh-muted); font-size: 12px; }
.exam-score-bar { max-width: 430px; height: 8px; margin: 12px auto 20px; overflow: hidden; background: var(--eh-line); border-radius: 4px; }
.exam-score-bar span { display: block; height: 100%; background: var(--eh-green); }
.exam-review { margin-top: 17px; text-align: left; }
.exam-review-item { margin-bottom: 10px; padding: 12px; background: var(--eh-panel-2); border: 1px solid var(--eh-line); border-radius: 7px; font-size: 11px; }
.exam-review-item strong { display: block; margin-bottom: 4px; }
.exam-review-item p { margin: 4px 0 0; color: var(--eh-muted); line-height: 1.6; }
.exam-wrong-item { margin-bottom: 11px; padding: 13px; background: var(--eh-panel-2); border: 1px solid var(--eh-line); border-radius: 8px; }
.exam-wrong-meta { display: flex; gap: 8px; align-items: center; flex-wrap: wrap; margin-bottom: 7px; color: var(--eh-muted); font-size: 10px; }
.exam-wrong-meta .tag { padding: 2px 7px; color: var(--eh-teal); background: var(--eh-teal-soft); border-radius: 4px; }
.exam-wrong-q { margin-bottom: 7px; font-size: 12px; font-weight: 600; line-height: 1.55; }
.exam-wrong-answer { margin: 3px 0; font-size: 10.5px; }
.exam-wrong-answer .bad { color: var(--eh-red); font-weight: 600; }
.exam-wrong-answer .good { color: var(--eh-green); font-weight: 600; }
.exam-wrong-solution { margin-top: 7px; padding: 8px 10px; color: var(--eh-muted); background: var(--eh-panel); border-radius: 5px; font-size: 10px; line-height: 1.6; }
.exam-empty { padding: 34px 0; color: var(--eh-muted); text-align: center; font-size: 12px; line-height: 1.8; }
.exam-toast { position: fixed; right: 22px; bottom: 22px; z-index: 120; max-width: 330px; padding: 10px 13px; color: #fff; background: var(--eh-navy); border-radius: 6px; box-shadow: var(--eh-shadow); font-size: 10px; opacity: 0; transform: translateY(8px); pointer-events: none; transition: .2s; }
.exam-toast.show { opacity: 1; transform: translateY(0); }

@media (max-width: 1080px) {
  .exam-header { padding-inline: 16px; gap: 12px; }
  .exam-brand { min-width: 230px; }
  .exam-actions .exam-back-link { display: none; }
  .exam-workspace { padding-inline: 24px; }
}
@media (max-width: 820px) {
  :root { --eh-sidebar: 240px; }
  .exam-search { max-width: none; }
  .exam-brand { min-width: 190px; }
  .exam-brand-copy b { font-size: 12px; }
  .exam-action-btn[data-action="wrongbook"] { display: none; }
  .exam-hero { grid-template-columns: 1fr; align-items: start; }
  .exam-meta-grid { max-width: 420px; }
  .exam-concept-tools { grid-template-columns: 1fr; }
  .exam-lower-grid { grid-template-columns: 1fr; }
}
@media (max-width: 620px) {
  body { font-size: 13px; }
  .exam-header { min-height: 60px; padding: 8px 12px; flex-wrap: wrap; }
  .exam-brand { min-width: 0; flex: 1 1 100%; }
  .exam-brand-copy b { max-width: calc(100vw - 74px); }
  .exam-search { order: 3; flex: 1 1 100%; }
  .exam-actions { position: absolute; top: 14px; right: 12px; }
  .exam-action-btn.primary { padding-inline: 9px; }
  .exam-shell { display: block; }
  .exam-sidebar { position: static; height: auto; max-height: none; padding: 14px 12px 10px; border-right: 0; border-bottom: 1px solid var(--eh-line); }
  .exam-sidebar-head { padding-bottom: 9px; }
  .exam-track-list { display: flex; gap: 7px; overflow-x: auto; padding-bottom: 3px; }
  .exam-track-btn { flex: 0 0 205px; min-height: 59px; }
  .exam-progress-card { margin: 10px 0 0; }
  .exam-sidebar-note { display: none; }
  .exam-workspace { padding: 16px 12px 50px; }
  .exam-hero { padding: 18px; }
  .exam-hero h1 { font-size: 25px; }
  .exam-meta-grid { grid-template-columns: repeat(3, 1fr); width: 100%; gap: 5px; }
  .exam-metric { min-width: 0; padding: 8px 4px; }
  .exam-metric b { font-size: 15px; }
  .exam-metric span { font-size: 8px; }
  .exam-unit-nav { padding: 10px; }
  .exam-unit-tabs { grid-auto-columns: minmax(158px, 1fr); }
  .exam-unit-heading { grid-template-columns: 1fr; gap: 8px; }
  .exam-unit-heading h2 { font-size: 22px; }
  .exam-unit-time { justify-self: start; }
  .exam-concept-head { grid-template-columns: 29px minmax(0,1fr); gap: 8px; }
  .exam-concept-num { width: 28px; height: 28px; font-size: 9px; }
  .exam-master-btn { grid-column: 2; justify-self: start; }
  .exam-concept-body { padding: 13px; }
  .exam-lower-card { padding: 14px; }
  .exam-unit-practice-head { align-items: flex-start; flex-direction: column; }
  .exam-unit-practice-actions { width: 100%; justify-content: space-between; }
  .exam-bank-summary { align-items: flex-start; flex-direction: column; }
  .exam-complete { align-items: flex-start; flex-direction: column; }
  .exam-unit-pager { flex-direction: column; }
  .exam-unit-pager button { max-width: none; width: 100%; }
  .exam-footer { flex-direction: column; gap: 5px; }
  .exam-modal { padding: 12px 8px 32px; }
  .exam-modal-panel { padding: 16px 13px; }
  .exam-modal-head h2 { font-size: 16px; }
  .exam-exam-option { font-size: 10.5px; }
  .exam-score { font-size: 34px; }
  .exam-toast { right: 12px; bottom: 12px; left: 12px; max-width: none; }
}