:root {
  --bg: #f6f2ec;
  --card: #fffaf3;
  --ink: #1a1a1a;
  --muted: #6f6a63;
  --line: #e3d9cc;
  --accent: #d24b3c;
}

* { box-sizing: border-box; }

body {
  margin: 0;
  font-family: "Times New Roman", "Noto Serif SC", "Songti SC", "SimSun", serif;
  background: var(--bg);
  color: var(--ink);
}

a { color: inherit; text-decoration: none; }

.topbar {
  border-bottom: 1px solid var(--line);
  background: #f8f3ec;
}

.topbar-inner {
  max-width: 980px;
  margin: 0 auto;
  padding: 14px 24px;
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 16px;
}

.brand { font-weight: 700; font-size: 18px; }

.nav { display: flex; gap: 12px; }
.nav a { padding: 6px 8px; border-radius: 6px; }
.nav a:hover { background: #fff4e5; }
.nav-user { padding: 6px 8px; color: var(--muted); }

.nav-dropdown { position: relative; display: flex; align-items: center; }
.nav-dropdown::after {
  content: "";
  position: absolute;
  left: -6px;
  right: -6px;
  top: 100%;
  height: 8px;
}
.nav-trigger {
  padding: 6px 8px;
  border-radius: 6px;
  border: 0;
  background: transparent;
  font: inherit;
  cursor: pointer;
}
.nav-trigger:hover,
.nav-dropdown.open .nav-trigger,
.nav-dropdown:focus-within .nav-trigger { background: #fff4e5; }

.nav-menu {
  position: absolute;
  top: 100%;
  left: 50%;
  transform: translateX(-50%);
  display: none;
  min-width: 140px;
  background: #fff;
  border: 1px solid var(--line);
  border-radius: 10px;
  padding: 6px;
  box-shadow: 0 8px 20px rgba(26, 26, 26, 0.08);
  z-index: 10;
}
.nav-menu a { display: block; padding: 8px 10px; border-radius: 8px; }
.nav-menu a:hover { background: #fff4e5; }

.nav-dropdown:hover .nav-menu,
.nav-dropdown.open .nav-menu,
.nav-dropdown:focus-within .nav-menu { display: block; }

.modal-card .muted#topic-start-subtitle { margin: 2px 0 10px; }

.lang-switch {
  margin-left: 12px;
  display: inline-flex;
  align-items: center;
  gap: 6px;
  border: 1px solid var(--line);
  background: #fff;
  border-radius: 999px;
  padding: 4px 6px;
}
.lang-pill {
  border: 0;
  background: transparent;
  padding: 4px 10px;
  border-radius: 999px;
  cursor: pointer;
  font: inherit;
  color: var(--muted);
}
.lang-pill.is-active {
  background: #e8f4ff;
  color: #0f3b7b;
  font-weight: 700;
}
.lang-pill.is-active[data-lang="zh"] {
  background: #fff3d6;
  color: #8b5a00;
}
.lang-divider { color: var(--line); }

.container { max-width: 980px; margin: 30px auto; padding: 0 16px; }

.hero {
  display: grid;
  grid-template-columns: 1fr;
  gap: 24px;
  align-items: start;
}

.hero-card {
  background: var(--card);
  border: 1px solid var(--line);
  border-radius: 12px;
  padding: 16px;
}

.schedule-strip {
  margin: 18px 0 0;
  display: grid;
  gap: 12px;
  justify-items: center;
}

.schedule-title {
  font-weight: 700;
  font-size: 18px;
  width: 100%;
  text-align: center;
}

.schedule-row {
  display: flex;
  gap: 12px;
  flex-wrap: wrap;
  justify-content: center;
}

.schedule-item {
  background: #fff;
  border: 1px solid var(--line);
  border-radius: 12px;
  padding: 12px 14px;
  min-width: 160px;
  display: grid;
  gap: 6px;
}

.schedule-head { display: flex; align-items: center; gap: 8px; }
.schedule-icon { width: 18px; height: 18px; color: var(--accent); display: inline-flex; }
.schedule-icon svg { width: 18px; height: 18px; fill: none; stroke: currentColor; stroke-width: 1.6; }

.schedule-exam { font-weight: 700; }

.quick-start { margin-top: 24px; }

.level-grid { display: grid; grid-template-columns: repeat(auto-fit, minmax(120px, 1fr)); gap: 10px; }
.level-card { border: 1px solid var(--line); background: #fff; border-radius: 10px; padding: 12px; display: block; }
.level-title { font-weight: 700; }

.cta-row { display: flex; gap: 12px; margin-top: 12px; align-items: center; flex-wrap: wrap; }
.cta-row .muted { margin: 0; line-height: 1.2; }

.btn {
  display: inline-flex;
  align-items: center;
  padding: 8px 14px;
  border-radius: 8px;
  border: 1px solid var(--line);
  background: #fff;
  cursor: pointer;
  line-height: 1.2;
}

.btn.primary { background: var(--accent); color: #fff; border-color: var(--accent); }
.btn.ghost { background: #fff; }

.text-link { color: var(--accent); }
.link-button { background: none; border: 0; padding: 0; font: inherit; cursor: pointer; }

.card {
  background: var(--card);
  border: 1px solid var(--line);
  border-radius: 12px;
  padding: 20px;
  position: relative;
}

.form { display: grid; gap: 10px; max-width: 420px; }
.inline-form { display: flex; gap: 10px; align-items: center; margin-bottom: 12px; flex-wrap: wrap; }

label { font-weight: 600; }
input, select { padding: 8px 10px; border: 1px solid var(--line); border-radius: 8px; background: #fff; }

.muted { color: var(--muted); }

.info-center { margin-top: 26px; }
.info-grid { display: grid; grid-template-columns: repeat(auto-fit, minmax(240px, 1fr)); gap: 16px; }
.info-card { background: var(--card); border: 1px solid var(--line); border-radius: 12px; padding: 16px; }
.amc-score-number { color: #c62828; font-size: 1.5em; font-weight: 700; }
.amc-highlight {
  background: #fff1a8;
  padding: 0 4px;
  border-radius: 4px;
  font-weight: 700;
}
.tips-article p { margin: 0 0 12px; line-height: 1.6; }
.tips-article p:last-child { margin-bottom: 0; }

.account-header { margin-top: 6px; }
.account-grid { display: grid; gap: 16px; margin-top: 16px; }
.account-form { display: grid; gap: 10px; }
.form-grid { display: grid; grid-template-columns: repeat(auto-fit, minmax(220px, 1fr)); gap: 10px; }
.form-field { display: grid; gap: 6px; }
.verify-actions { display: flex; gap: 10px; flex-wrap: wrap; margin-top: 10px; }
.plan-card .text-link { margin-top: 6px; }
.account-card { background: var(--card); border: 1px solid var(--line); border-radius: 12px; padding: 16px; }
.activity-list { display: grid; gap: 12px; margin-top: 10px; }
.activity-row { border: 1px solid var(--line); background: #fff; border-radius: 10px; padding: 12px; display: grid; gap: 6px; }
.activity-title { font-weight: 700; }
.activity-meta { color: var(--muted); font-size: 14px; }
.activity-wrong { display: flex; gap: 8px; flex-wrap: wrap; font-size: 14px; }
.activity-actions { font-size: 14px; display: flex; align-items: center; gap: 8px; }
.divider-dot { color: var(--muted); }
.notice-box { padding: 10px 12px; border-radius: 8px; background: #e9f3ff; border: 1px solid #b9d7ff; color: #17427a; margin-top: 12px; }
.inline-check { display: flex; align-items: center; gap: 8px; margin-top: 10px; }
.subscription-list { display: grid; gap: 10px; margin-top: 10px; }
.subscription-row { border: 1px solid var(--line); background: #fff; border-radius: 10px; padding: 12px; display: flex; justify-content: space-between; align-items: center; gap: 12px; }
.subscription-main { min-width: 0; }
.subscription-actions { flex: 0 0 auto; display: flex; align-items: center; gap: 10px; }
.subscription-header { display: flex; align-items: center; justify-content: space-between; gap: 12px; }
.btn.small { padding: 6px 10px; font-size: 15px; }
.btn.is-loading { opacity: 0.65; cursor: wait; }
.subscription-title { font-weight: 700; }
.subscription-meta { color: var(--muted); font-size: 14px; }

.amc-info-header { margin-top: 6px; }
.amc-info-header h1 { margin-bottom: 6px; }
.latest-updates { margin-top: 20px; }

.date-list { display: grid; gap: 8px; }
.date-row { display: grid; grid-template-columns: 80px 1fr auto; gap: 8px; align-items: center; }
.date-label { font-weight: 700; }
.date-countdown { color: var(--accent); font-weight: 700; }

.feature-grid { display: grid; grid-template-columns: repeat(auto-fit, minmax(240px, 1fr)); gap: 16px; margin-top: 24px; }
.feature { background: #fff; border: 1px solid var(--line); border-radius: 12px; padding: 16px; position: relative; }
.feature-links { display: flex; gap: 12px; flex-wrap: wrap; }
.mock-section { margin-top: 16px; }

.home-page .schedule-strip { margin: 10px 0 0; gap: 8px; }
.home-page .schedule-title { font-size: 28px; }
.home-page .schedule-row { gap: 10px; }
.home-page .schedule-item { padding: 10px 12px; min-width: 150px; gap: 4px; }
.home-page .hero { gap: 16px; }
.home-page .hero h1 { margin: 8px 0 6px; font-size: 26px; }
.home-page .hero p { margin: 0 0 10px; }
.home-page .quick-start { margin-top: 16px; }
.home-page .hero-card { padding: 12px; }
.home-page .feature-grid { margin-top: 16px; gap: 12px; }
.home-page .feature { padding: 12px; }
.home-page .mock-section { margin-top: 12px; }
.home-page .purchase-grid { gap: 12px; }
.purchase-grid { display: grid; grid-template-columns: repeat(auto-fit, minmax(240px, 1fr)); gap: 16px; }
.purchase-block { position: relative; }
.purchase-badge {
  background: #fff3d6;
  color: #8b5a00;
  border: 1px solid #f1d39a;
}
.free-badge {
  background: #e8f4ff;
  color: #0f3b7b;
  border: 1px solid #c6defa;
}
.coming-soon-badge {
  background: #f5f1ff;
  color: #50328a;
  border: 1px solid #d8cdf2;
}

.modal-backdrop {
  position: fixed;
  inset: 0;
  background: rgba(26, 26, 26, 0.45);
  display: none;
  align-items: center;
  justify-content: center;
  padding: 20px;
  z-index: 1000;
}
.modal-backdrop.open { display: flex; }
.modal-card {
  width: min(860px, 95vw);
  background: #fffaf3;
  border: 1px solid var(--line);
  border-radius: 16px;
  padding: 20px;
  box-shadow: 0 18px 60px rgba(26, 26, 26, 0.2);
}
.confirm-card { width: min(520px, 92vw); }
.modal-actions { display: flex; justify-content: flex-end; gap: 10px; margin-top: 16px; }
.confirm-card p { margin-top: 12px; color: var(--muted); }
.modal-header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 12px;
}
.icon-button {
  border: 1px solid var(--line);
  background: #fff;
  border-radius: 8px;
  padding: 6px 10px;
  cursor: pointer;
  font-size: 16px;
}
.flow-diagram {
  margin-top: 16px;
  display: grid;
  grid-template-columns: repeat(5, minmax(120px, 1fr));
  gap: 8px;
  align-items: center;
}
.flow-step {
  border: 1px solid var(--line);
  background: #fff;
  border-radius: 12px;
  padding: 10px;
  text-align: center;
}
.flow-title { font-weight: 700; margin-bottom: 4px; }
.flow-text { font-size: 14px; color: var(--muted); }
.flow-arrow { text-align: center; font-weight: 700; color: var(--accent); }
.modal-points { margin-top: 14px; display: grid; gap: 6px; }
.point-item { font-size: 14px; color: var(--muted); }

.plan-grid { display: grid; grid-template-columns: repeat(auto-fit, minmax(220px, 1fr)); gap: 16px; margin-top: 16px; }
.plan-card {
  border: 1px solid var(--line);
  background: #fff;
  border-radius: 12px;
  padding: 16px;
  position: relative;
  display: flex;
  flex-direction: column;
  gap: 8px;
}
.plan-card .btn { align-self: flex-start; }
.btn[disabled] { opacity: 0.6; cursor: not-allowed; }
.plan-title { font-weight: 700; margin-bottom: 6px; }
.plan-price { font-weight: 700; color: var(--accent); margin-bottom: 6px; }
.badge { position: absolute; top: 12px; right: 12px; background: #e8f4e6; color: #1c6b37; border: 1px solid #cde7d3; padding: 4px 8px; border-radius: 999px; font-size: 14px; }
.mock-links { display: flex; gap: 10px; margin-top: 16px; flex-wrap: wrap; }
.placeholder { padding: 16px; border: 1px dashed var(--line); border-radius: 12px; background: #fff; }

.paper-list { display: grid; gap: 10px; }
.paper-row { display: grid; grid-template-columns: 1fr auto; gap: 10px; padding: 10px 12px; border-radius: 10px; border: 1px solid var(--line); background: #fff; }
.paper-grid { display: grid; grid-template-columns: repeat(4, minmax(0, 1fr)); gap: 10px; }
.paper-card { display: grid; gap: 4px; padding: 10px 12px; border-radius: 10px; border: 1px solid var(--line); background: #fff; }
.paper-card .paper-meta { text-align: right; color: var(--muted); font-size: 14px; }
@media (max-width: 1100px) {
  .paper-grid { grid-template-columns: repeat(3, minmax(0, 1fr)); }
}
@media (max-width: 900px) {
  .paper-grid { grid-template-columns: repeat(2, minmax(0, 1fr)); }
}
@media (max-width: 640px) {
  .paper-grid { grid-template-columns: 1fr; }
}
.paper-title { font-weight: 700; }
.link-button { background: none; border: 0; padding: 0; cursor: pointer; }

.question-card { border: 1px solid var(--line); border-radius: 12px; padding: 14px; background: #fff; margin: 14px 0; font-size: 16px; }
.q-title { font-weight: 700; }
.q-title-row { display: flex; align-items: center; gap: 10px; margin-bottom: 6px; }
.q-source { font-size: 12px; color: var(--muted); background: #fffdf7; border: 1px solid var(--line); border-radius: 999px; padding: 2px 8px; }
.result-header { display: flex; align-items: center; gap: 10px; font-weight: 700; }
.q-body { margin-bottom: 10px; font-size: 24px; line-height: 1.65; }
.q-body .lang-en, .q-body .lang-zh { font-size: 24px; }
.question-card .q-body { font-size: 24px !important; line-height: 1.65 !important; }
.question-card img { max-width: 100%; height: auto; }

.stem-images { display: flex; flex-direction: column; gap: 10px; margin: 10px 0; align-items: flex-start; }
.stem-images img { width: auto; max-width: 100%; height: auto; border: 1px solid var(--line); border-radius: 8px; background: #fff; }

.choices-block { display: grid; gap: 8px; }
.choice { display: flex; gap: 8px; align-items: start; }
.choice-text { font-size: 16px; line-height: 1.5; }
.choice-key { font-size: 16px; }
.choice-key { font-weight: 700; }
.choice-img { width: auto; max-width: 100%; height: auto; border: 1px solid var(--line); border-radius: 6px; background: #fff; display: inline-block; }
.choice-list { display: grid; gap: 8px; margin-top: 8px; }
.choice-row { display: grid; grid-template-columns: 40px 1fr; gap: 8px; align-items: start; }
.result-list { display: grid; gap: 16px; }
.result-item { background: #fff; border: 1px solid var(--line); border-radius: 12px; padding: 16px; }
.result-header { font-weight: 700; margin-bottom: 6px; }
.centered-images { align-items: center; justify-content: center; }

.solution-box {
  margin-top: 10px;
  padding: 10px;
  background: #fff6e8;
  border: 1px dashed var(--line);
  border-radius: 8px;
  font-size: 24px;
  line-height: 1.65;
}
.solution-box .lang-en,
.solution-box .lang-zh { font-size: 24px; }

.report-summary { margin-bottom: 16px; }
.summary-title { font-weight: 700; margin: 6px 0 8px; }
.summary-table-wrap { overflow-x: auto; }
.report-table {
  width: 100%;
  border-collapse: collapse;
  background: #fff;
  border: 1px solid var(--line);
  border-radius: 12px;
  overflow: hidden;
  font-size: 14px;
}
.report-table th,
.report-table td {
  padding: 10px 12px;
  border-bottom: 1px solid var(--line);
  text-align: left;
  vertical-align: top;
}
.report-table th { background: #fff6e8; font-weight: 700; }
.summary-row { cursor: pointer; }
.summary-row:hover { background: #faf4e9; }
.summary-total td { font-weight: 700; background: #fffaf2; }

.result-item .choice-list {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(180px, 1fr));
  gap: 8px 16px;
}
.result-item .choice-row {
  display: flex;
  gap: 8px;
  align-items: start;
}
.report-email-form { margin: 8px 0 12px; }
.pdf-hidden { display: none !important; }

.score-box { padding: 10px 12px; border-radius: 8px; background: #fff6e8; border: 1px solid var(--line); margin-bottom: 10px; font-weight: 700; }
.honor-box { background: #f6fbff; border: 1px solid #cfe2f3; padding: 12px 14px; border-radius: 12px; margin-bottom: 12px; }
.honor-title { font-weight: 700; margin-bottom: 4px; }
.honor-score { font-weight: 700; }
.honor-range { color: var(--muted); margin-top: 2px; font-size: 13px; }
.honor-message { margin-top: 6px; }
.timer-box {
  display: inline-flex;
  gap: 10px;
  align-items: center;
  padding: 8px 12px;
  border-radius: 8px;
  border: 1px solid var(--line);
  background: #fff;
  font-weight: 700;
  margin-bottom: 10px;
}
.timer-label { color: var(--muted); font-weight: 600; }
.timer-value { color: var(--accent); font-weight: 700; }
.diag-lang-toggle { position: absolute; top: 16px; right: 16px; }
.error-box { padding: 10px 12px; border-radius: 8px; background: #fff1f0; border: 1px solid #f2c7c2; color: #9c2a1f; margin-bottom: 10px; }
.divider { height: 1px; background: var(--line); margin: 14px 0; }
.result-line { margin-top: 8px; font-weight: 700; }
.result-line.good { color: #1c6b37; }
.result-line.bad { color: #9c2a1f; }

.image-row { display: flex; gap: 10px; flex-wrap: wrap; margin: 8px 0; }
.image-row img { max-width: 100%; height: auto; border: 1px solid var(--line); border-radius: 8px; background: #fff; }

.form-actions { margin-top: 12px; }

.question-stack [data-step] { display: none; }
.question-stack [data-step].active { display: block; }
.stepper { display: flex; gap: 8px; margin-top: 12px; justify-content: space-between; }
.stepper .btn { min-width: 72px; }
.floating-nav {
  position: absolute;
  top: 58%;
  transform: translateY(-50%);
  display: flex;
  flex-direction: column;
  gap: 10px;
  z-index: 50;
}
.floating-nav.left { left: -44px; }
.floating-nav.right { right: -44px; }
.pill {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  padding: 10px 14px;
  border-radius: 999px;
  border: 1px solid var(--line);
  background: #fffaf2;
  color: var(--ink);
  font-weight: 700;
  cursor: pointer;
  box-shadow: 0 6px 14px rgba(0,0,0,0.08);
}
.submit-right { display: flex; justify-content: flex-end; }
.jump-nav { display: flex; flex-wrap: wrap; gap: 14px; margin-top: 12px; }
.jump-pill { display: inline-flex; align-items: center; justify-content: center; min-width: 36px; height: 34px; padding: 0 12px; border-radius: 999px; border: 1px solid var(--line); color: var(--text); background: #fff; font-weight: 600; font-size: 14px; text-decoration: none; }
.jump-pill:hover { border-color: var(--accent); color: var(--accent); }
.jump-pill.active { background: var(--accent); color: #fff; border-color: var(--accent); box-shadow: 0 6px 12px rgba(0,0,0,0.12); }

.topic-list { display: grid; gap: 10px; }
.topic-row { display: grid; grid-template-columns: 120px 1fr auto; gap: 10px; padding: 10px 12px; border-radius: 10px; border: 1px solid var(--line); background: #fff; }
.topic-code { font-weight: 700; }
.topic-meta { color: var(--muted); }
.topic-count { color: #2a63c7; font-weight: 700; }
.topic-head { display: flex; align-items: flex-start; justify-content: space-between; gap: 12px; }
.topic-head-actions { display: inline-flex; align-items: center; gap: 10px; }
.topic-title { margin: 0 0 6px; }
.topic-subtitle { margin: 0; color: var(--muted); }
.q-meta { margin-top: 6px; }
.mini-badge {
  display: inline-flex;
  align-items: center;
  padding: 2px 8px;
  border-radius: 999px;
  border: 1px solid var(--line);
  background: #fff;
  color: var(--muted);
  font-size: 13px;
  font-weight: 700;
}
.mini-badge-good { background: #e8f4e6; border-color: #cde7d3; color: #1c6b37; }
.topic-steps { margin-top: 16px; }
.topic-practice .question-card { margin-top: 16px; }
.topic-nav-row { margin-top: 14px; display: flex; align-items: center; justify-content: space-between; padding-top: 6px; }
.topic-reveal-actions { display: flex; gap: 10px; align-items: center; flex-wrap: wrap; margin-top: 14px; }
.answer-box { margin-top: 10px; padding: 12px; border-radius: 10px; border: 1px solid var(--line); background: #fff; }
.topic-practice .choice { border: 1px solid transparent; padding: 4px 6px; border-radius: 10px; }
.topic-practice .choice.is-correct { border-color: #2e7d32; }
.topic-practice .choice.is-selected { box-shadow: 0 0 0 2px rgba(210, 75, 60, 0.18); }
.solution-images { margin-top: 10px; display: grid; gap: 10px; justify-items: center; }
.solution-images img { max-width: 520px; width: 100%; height: auto; border-radius: 10px; border: 1px solid var(--line); background: #fff; }
.youtube-box { margin-top: 12px; display: grid; gap: 12px; }
.youtube-box iframe { width: 100%; max-width: 720px; aspect-ratio: 16 / 9; border: 0; border-radius: 10px; background: #000; justify-self: center; }
.level-note { margin: 6px 0 12px; }
.radio-row { display: flex; flex-wrap: wrap; gap: 10px; }
.radio-pill { display: inline-flex; align-items: center; gap: 8px; padding: 8px 12px; border: 1px solid var(--line); background: #fff; border-radius: 999px; cursor: pointer; }
.radio-pill input { margin: 0; }
.radio-pill.checked { border-color: var(--accent); box-shadow: 0 6px 12px rgba(0,0,0,0.08); }

[data-content-lang="en"] .lang-zh { display: none; }
[data-content-lang="zh"] .lang-en { display: none; }

/* Practice review: hide solutions by default, reveal via JS toggle */
[data-show-solutions="0"] .solution-box { display: none; }

@media (max-width: 860px) {
  .flow-diagram { grid-template-columns: 1fr; }
  .flow-arrow { display: none; }
  .flow-step { text-align: left; }
}

@media (max-width: 820px) {
  .hero { grid-template-columns: 1fr; }
  .nav { display: none; }
}

@media (max-width: 900px) {
  .floating-nav {
    position: static;
    transform: none;
    flex-direction: row;
    justify-content: space-between;
    margin: 12px 0;
  }
  .floating-nav.left,
  .floating-nav.right {
    left: auto;
    right: auto;
  }
}