:root {
  --red: #b4232a;
  --red-dark: #841b21;
  --red-soft: #f8e7e6;
  --ink: #20252c;
  --muted: #6f747b;
  --line: #e5dfd6;
  --paper: #fffdf9;
  --canvas: #f3f0eb;
  --green: #28765a;
  --green-soft: #e6f3ed;
  --amber: #9a6817;
  --amber-soft: #fbf1d9;
  --blue: #315f87;
  --blue-soft: #e8f0f7;
  --shadow: 0 16px 40px rgba(43, 35, 28, 0.08);
  --radius: 18px;
}

* { box-sizing: border-box; }

html { color-scheme: light; }

body {
  margin: 0;
  background: var(--canvas);
  color: var(--ink);
  font-family: -apple-system, BlinkMacSystemFont, "SF Pro Text", "PingFang SC", "Microsoft YaHei", sans-serif;
  -webkit-font-smoothing: antialiased;
}

button, input, select, textarea { font: inherit; }

button { color: inherit; }

.app-shell { min-height: 100vh; display: grid; grid-template-columns: 244px minmax(0, 1fr); }

.sidebar {
  position: sticky;
  top: 0;
  height: 100vh;
  padding: 24px 18px 20px;
  background: #20252c;
  color: #fff;
  display: flex;
  flex-direction: column;
  z-index: 20;
}

.brand {
  width: 100%;
  border: 0;
  background: transparent;
  color: inherit;
  display: flex;
  align-items: center;
  gap: 12px;
  text-align: left;
  padding: 4px 8px 24px;
  cursor: pointer;
}

.brand-mark {
  width: 42px;
  height: 42px;
  border-radius: 13px;
  display: grid;
  place-items: center;
  background: var(--red);
  font-family: -apple-system, "Helvetica Neue", "Arial", sans-serif;
  font-size: 17px;
  letter-spacing: 0.02em;
  font-weight: 800;
  box-shadow: 0 8px 20px rgba(180, 35, 42, 0.36);
}

.brand strong { display: block; font-size: 18px; letter-spacing: 0.04em; }
.brand small { display: block; margin-top: 4px; color: #969da6; font-size: 11px; }

.side-nav { display: grid; gap: 6px; }

.side-nav button {
  width: 100%;
  min-height: 46px;
  border: 0;
  border-radius: 12px;
  padding: 0 13px;
  display: flex;
  gap: 12px;
  align-items: center;
  background: transparent;
  color: #c9cdd2;
  cursor: pointer;
  text-align: left;
  transition: 160ms ease;
}

.side-nav button:hover { color: #fff; background: rgba(255,255,255,.06); }
.side-nav button.active { color: #fff; background: var(--red); box-shadow: 0 8px 22px rgba(180,35,42,.25); }
.side-nav button span { width: 18px; font-size: 20px; text-align: center; opacity: .9; }
.side-nav button b { margin-left: auto; min-width: 22px; padding: 2px 7px; border-radius: 999px; background: rgba(255,255,255,.14); font-size: 11px; text-align: center; }

.sidebar-foot { margin-top: auto; display: grid; gap: 14px; }
.offline-note { padding: 13px 11px; border: 1px solid rgba(255,255,255,.08); border-radius: 12px; display: flex; align-items: center; gap: 10px; color: #d5d8dc; font-size: 12px; line-height: 1.35; }
.offline-note i { width: 8px; height: 8px; flex: 0 0 auto; border-radius: 50%; background: #5ac18e; box-shadow: 0 0 0 5px rgba(90,193,142,.1); }
.offline-note small { color: #8e959e; }
.text-button { border: 0; background: transparent; color: #9198a1; font-size: 12px; cursor: pointer; text-align: left; padding: 0 10px; }
.text-button:hover { color: #fff; }

.main-area { min-width: 0; padding: 0 46px 54px; }
.topbar { min-height: 118px; max-width: 1220px; margin: 0 auto; display: flex; align-items: center; justify-content: space-between; gap: 20px; }
.topbar p { margin: 0 0 7px; color: var(--red); font-size: 12px; font-weight: 700; letter-spacing: .14em; }
.topbar h1 { margin: 0; font-family: "Songti SC", "STSong", serif; font-size: clamp(25px, 3vw, 34px); line-height: 1.2; font-weight: 700; }
.top-actions { display: flex; align-items: center; gap: 10px; }
.streak-pill { padding: 9px 13px; border-radius: 999px; background: var(--paper); border: 1px solid var(--line); color: var(--amber); font-size: 12px; font-weight: 700; white-space: nowrap; }
.icon-button { width: 38px; height: 38px; border: 1px solid var(--line); border-radius: 50%; background: var(--paper); cursor: pointer; font-size: 20px; }

#app { max-width: 1220px; margin: 0 auto; outline: none; }

.surface { background: var(--paper); border: 1px solid rgba(219,211,201,.8); border-radius: var(--radius); box-shadow: var(--shadow); }
.section { margin-top: 22px; }
.section-head { display: flex; justify-content: space-between; gap: 18px; align-items: end; margin: 0 2px 12px; }
.section-head h2 { margin: 0; font-family: "Songti SC", serif; font-size: 20px; }
.section-head p { margin: 4px 0 0; color: var(--muted); font-size: 13px; }

.hero-grid { display: grid; grid-template-columns: minmax(0, 1.5fr) minmax(280px, .8fr); gap: 18px; }
.daily-card { overflow: hidden; position: relative; min-height: 250px; padding: 30px 32px; color: #fff; background: linear-gradient(135deg, #a71f26 0%, #c93438 68%, #d85d4e 100%); }
.daily-card::after { content: ""; position: absolute; width: 310px; height: 310px; right: -115px; bottom: -180px; border: 45px solid rgba(255,255,255,.08); border-radius: 50%; }
.daily-card::before { content: ""; position: absolute; width: 170px; height: 170px; right: 75px; top: -95px; border: 1px solid rgba(255,255,255,.14); border-radius: 50%; }
.daily-card > * { position: relative; z-index: 1; }
.daily-card .kicker { font-size: 12px; opacity: .75; letter-spacing: .16em; }
.daily-card h2 { max-width: 550px; margin: 14px 0 8px; font-family: "Songti SC", serif; font-size: clamp(27px, 3.2vw, 40px); line-height: 1.2; }
.daily-card p { max-width: 560px; margin: 0; opacity: .78; font-size: 14px; line-height: 1.7; }
.hero-actions { margin-top: 24px; display: flex; gap: 10px; flex-wrap: wrap; }
.primary-button, .secondary-button, .ghost-button {
  min-height: 42px;
  border-radius: 11px;
  padding: 0 18px;
  font-weight: 700;
  cursor: pointer;
  border: 1px solid transparent;
  transition: transform 120ms ease, box-shadow 120ms ease, background 120ms ease;
}
.primary-button:hover, .secondary-button:hover, .ghost-button:hover { transform: translateY(-1px); }
.primary-button { background: var(--red); color: #fff; box-shadow: 0 8px 20px rgba(180,35,42,.2); }
.daily-card .primary-button { background: #fff; color: var(--red-dark); box-shadow: 0 8px 24px rgba(91,15,20,.18); }
.secondary-button { background: var(--ink); color: #fff; }
.daily-card .secondary-button { background: rgba(255,255,255,.12); border-color: rgba(255,255,255,.2); }
.ghost-button { background: transparent; color: var(--ink); border-color: var(--line); box-shadow: none; }
.small-button { min-height: 34px; padding: 0 12px; border-radius: 9px; font-size: 12px; }
.danger-button { color: var(--red); border-color: #efc8c8; background: #fff7f6; }

.goal-card { min-height: 250px; padding: 25px; display: flex; flex-direction: column; justify-content: space-between; }
.goal-top { display: flex; justify-content: space-between; color: var(--muted); font-size: 12px; }
.goal-ring { --progress: 0deg; width: 112px; height: 112px; margin: 5px auto 10px; border-radius: 50%; display: grid; place-items: center; background: conic-gradient(var(--red) var(--progress), #ece6dd 0); position: relative; }
.goal-ring::after { content: ""; width: 84px; height: 84px; border-radius: 50%; background: var(--paper); position: absolute; }
.goal-ring strong { position: relative; z-index: 1; font-family: "Songti SC", serif; font-size: 27px; }
.goal-ring small { display: block; position: relative; z-index: 1; margin-top: -25px; padding-top: 32px; color: var(--muted); font-size: 10px; }
.goal-meta { display: flex; justify-content: space-around; text-align: center; }
.goal-meta strong { display: block; font-size: 17px; }
.goal-meta small { color: var(--muted); font-size: 11px; }

.stat-grid { display: grid; grid-template-columns: repeat(4, minmax(0, 1fr)); gap: 14px; }
.stat-card { padding: 18px; }
.stat-card small { color: var(--muted); font-size: 11px; }
.stat-card strong { display: block; margin-top: 9px; font-family: "Songti SC", serif; font-size: 27px; }
.stat-card span { display: block; margin-top: 6px; color: var(--muted); font-size: 11px; }

.quick-grid { display: grid; grid-template-columns: repeat(4, minmax(0, 1fr)); gap: 14px; }
.quick-card { padding: 18px; border: 1px solid var(--line); border-radius: 15px; background: var(--paper); cursor: pointer; text-align: left; transition: 160ms ease; }
.quick-card:hover { transform: translateY(-2px); box-shadow: var(--shadow); border-color: #d9cfc3; }
.quick-card .quick-icon { width: 38px; height: 38px; border-radius: 11px; display: grid; place-items: center; margin-bottom: 15px; color: var(--red); background: var(--red-soft); font-size: 18px; }
.quick-card:nth-child(2) .quick-icon { color: var(--green); background: var(--green-soft); }
.quick-card:nth-child(3) .quick-icon { color: var(--amber); background: var(--amber-soft); }
.quick-card:nth-child(4) .quick-icon { color: var(--blue); background: var(--blue-soft); }
.quick-card strong { display: block; font-size: 15px; }
.quick-card small { display: block; margin-top: 5px; color: var(--muted); line-height: 1.45; }

.split-grid { display: grid; grid-template-columns: 1.2fr .8fr; gap: 18px; }
.panel { padding: 22px; }
.topic-line { display: grid; grid-template-columns: minmax(130px, 1.4fr) 2fr 48px; gap: 12px; align-items: center; padding: 10px 0; border-bottom: 1px solid #eee9e2; font-size: 12px; }
.topic-line:last-child { border-bottom: 0; }
.topic-line > span:last-child { text-align: right; color: var(--muted); }
.progress-track { height: 7px; border-radius: 999px; overflow: hidden; background: #ece7df; }
.progress-track i { display: block; height: 100%; border-radius: inherit; background: var(--red); }
.empty-state { padding: 40px 20px; text-align: center; color: var(--muted); }
.empty-state .empty-icon { width: 58px; height: 58px; margin: 0 auto 14px; border-radius: 18px; display: grid; place-items: center; background: var(--green-soft); color: var(--green); font-size: 24px; }
.empty-state h3 { color: var(--ink); margin: 0 0 7px; font-family: "Songti SC", serif; }
.empty-state p { margin: 0 auto 16px; max-width: 430px; font-size: 13px; line-height: 1.6; }

.mode-grid, .topic-grid { display: grid; grid-template-columns: repeat(3, minmax(0, 1fr)); gap: 15px; }
.mode-card, .topic-card { padding: 22px; cursor: pointer; text-align: left; position: relative; overflow: hidden; transition: 160ms ease; }
.mode-card:hover, .topic-card:hover { transform: translateY(-2px); border-color: #d3c7bb; }
.mode-card .mode-icon { width: 44px; height: 44px; border-radius: 13px; display: grid; place-items: center; background: var(--red-soft); color: var(--red); font-size: 22px; }
.mode-card h3, .topic-card h3 { margin: 16px 0 7px; font-family: "Songti SC", serif; font-size: 20px; }
.mode-card p, .topic-card p { min-height: 40px; margin: 0; color: var(--muted); font-size: 12px; line-height: 1.6; }
.mode-card .mode-foot, .topic-card .topic-foot { margin-top: 18px; display: flex; justify-content: space-between; align-items: center; font-size: 11px; color: var(--muted); }
.mode-card .arrow, .topic-card .arrow { color: var(--red); font-size: 18px; }
.topic-card .topic-number { position: absolute; right: 18px; top: 14px; font-family: "Songti SC", serif; color: #ded6cd; font-size: 30px; }

.practice-layout { display: grid; grid-template-columns: minmax(0, 1fr) 230px; gap: 18px; align-items: start; }
.question-card { padding: clamp(20px, 4vw, 34px); }
.question-toolbar { display: flex; justify-content: space-between; align-items: center; gap: 14px; padding-bottom: 19px; border-bottom: 1px solid #eee9e2; }
.question-toolbar-left { display: flex; align-items: center; gap: 8px; flex-wrap: wrap; }
.type-tag, .topic-tag, .status-tag { display: inline-flex; align-items: center; min-height: 26px; padding: 0 9px; border-radius: 999px; background: var(--red-soft); color: var(--red); font-size: 10px; font-weight: 700; }
.topic-tag { background: #eeeae4; color: #625e58; }
.status-tag.good { background: var(--green-soft); color: var(--green); }
.status-tag.bad { background: var(--red-soft); color: var(--red); }
.favorite-button { border: 0; background: transparent; cursor: pointer; color: #a6a19a; font-size: 23px; }
.favorite-button.active { color: var(--amber); }
.question-number { color: var(--muted); font-size: 12px; }
.question-title { margin: 24px 0 22px; font-family: "Songti SC", "STSong", serif; font-size: clamp(20px, 2.5vw, 26px); line-height: 1.72; font-weight: 700; }
.option-list { display: grid; gap: 11px; }
.option-button { width: 100%; min-height: 56px; border: 1px solid var(--line); border-radius: 13px; padding: 12px 15px; display: grid; grid-template-columns: 34px minmax(0,1fr) 22px; align-items: center; gap: 11px; background: #fff; cursor: pointer; text-align: left; line-height: 1.5; transition: 120ms ease; }
.option-button:hover:not(:disabled) { border-color: #cdbeb3; background: #fffcf8; }
.option-key { width: 31px; height: 31px; border-radius: 9px; display: grid; place-items: center; background: #f0ece6; color: #4b4f54; font-weight: 700; font-size: 12px; }
.option-check { opacity: 0; color: #fff; text-align: center; }
.option-button.selected { border-color: var(--red); background: #fff8f7; box-shadow: inset 0 0 0 1px var(--red); }
.option-button.selected .option-key { background: var(--red); color: #fff; }
.option-button.selected .option-check { opacity: 1; color: var(--red); }
.option-button.correct { border-color: #79b89d; background: var(--green-soft); box-shadow: inset 0 0 0 1px #79b89d; }
.option-button.correct .option-key { background: var(--green); color: #fff; }
.option-button.correct .option-check { opacity: 1; color: var(--green); }
.option-button.wrong { border-color: #df8c8f; background: var(--red-soft); }
.option-button.wrong .option-key { background: var(--red); color: #fff; }
.question-actions { display: flex; justify-content: space-between; gap: 10px; margin-top: 22px; flex-wrap: wrap; }
.action-right { display: flex; gap: 9px; }
.feedback { margin-top: 22px; padding: 20px; border-radius: 14px; background: #f6f3ee; border-left: 4px solid var(--green); }
.feedback.wrong-feedback { border-left-color: var(--red); }
.feedback-head { display: flex; gap: 9px; align-items: center; margin-bottom: 11px; font-weight: 800; }
.feedback p { margin: 6px 0 0; font-size: 13px; line-height: 1.75; }
.memory-tip { margin-top: 12px !important; padding-top: 12px; border-top: 1px dashed #d9d1c7; color: #625d56; }
.short-answer-box { min-height: 150px; padding: 18px; border: 1px dashed #d8cfc4; border-radius: 13px; background: #fffcf8; color: var(--muted); line-height: 1.8; }
.short-answer-box textarea { width: 100%; min-height: 120px; resize: vertical; border: 0; outline: 0; background: transparent; color: var(--ink); line-height: 1.8; }
.self-check { margin-top: 13px; display: flex; gap: 9px; }

.session-side { position: sticky; top: 18px; display: grid; gap: 14px; }
.session-progress { padding: 18px; }
.session-progress strong { display: block; font-family: "Songti SC", serif; font-size: 22px; }
.session-progress p { margin: 5px 0 14px; color: var(--muted); font-size: 11px; }
.session-progress .progress-track { height: 9px; }
.session-stats { margin-top: 16px; display: grid; grid-template-columns: 1fr 1fr; gap: 8px; text-align: center; }
.session-stats div { padding: 10px 5px; border-radius: 10px; background: #f6f3ee; }
.session-stats b { display: block; font-size: 17px; }
.session-stats small { color: var(--muted); font-size: 10px; }
.shortcut-card { padding: 16px; color: var(--muted); font-size: 11px; line-height: 1.9; }
kbd { min-width: 21px; height: 21px; padding: 0 5px; display: inline-grid; place-items: center; border: 1px solid #d6cfc6; border-bottom-width: 2px; border-radius: 5px; background: #fff; color: #4f4b46; font: 10px inherit; }

.exam-bar { margin-bottom: 14px; padding: 14px 18px; display: flex; justify-content: space-between; align-items: center; gap: 14px; }
.exam-timer { font-variant-numeric: tabular-nums; font-size: 20px; font-weight: 800; color: var(--red); }
.exam-meta { color: var(--muted); font-size: 12px; }
.exam-grid { display: grid; grid-template-columns: repeat(5, 1fr); gap: 7px; }
.exam-grid button { aspect-ratio: 1; border: 1px solid var(--line); border-radius: 8px; background: #fff; cursor: pointer; font-size: 11px; }
.exam-grid button.answered { border-color: var(--red); background: var(--red-soft); color: var(--red); }
.exam-grid button.current { box-shadow: inset 0 0 0 2px var(--red); }
.score-hero { padding: 34px; display: grid; grid-template-columns: 150px minmax(0,1fr); gap: 28px; align-items: center; }
.score-circle { width: 140px; height: 140px; border-radius: 50%; display: grid; place-items: center; background: var(--red-soft); color: var(--red); border: 9px solid #f1cac8; }
.score-circle strong { display: block; text-align: center; font-family: "Songti SC", serif; font-size: 42px; }
.score-circle small { display: block; margin-top: -10px; font-size: 10px; }
.score-copy h2 { margin: 0 0 8px; font-family: "Songti SC", serif; font-size: 30px; }
.score-copy p { margin: 0; color: var(--muted); line-height: 1.7; }
.score-breakdown { margin-top: 18px; display: flex; gap: 18px; flex-wrap: wrap; }
.score-breakdown b { font-size: 20px; }
.score-breakdown small { display: block; color: var(--muted); }

.filters { padding: 14px; display: grid; grid-template-columns: minmax(220px,1fr) 180px 220px; gap: 10px; }
.field, .select-field { width: 100%; min-height: 42px; border: 1px solid var(--line); border-radius: 10px; background: #fff; padding: 0 12px; outline: none; }
.field:focus, .select-field:focus { border-color: var(--red); box-shadow: 0 0 0 3px rgba(180,35,42,.08); }
.bank-list { margin-top: 12px; display: grid; gap: 9px; }
.bank-item { overflow: hidden; }
.bank-item summary { list-style: none; padding: 16px 18px; display: grid; grid-template-columns: 56px minmax(0,1fr) auto; gap: 14px; align-items: center; cursor: pointer; }
.bank-item summary::-webkit-details-marker { display: none; }
.bank-id { color: var(--red); font-weight: 800; font-size: 12px; }
.bank-question { overflow: hidden; white-space: nowrap; text-overflow: ellipsis; font-family: "Songti SC", serif; font-size: 15px; }
.bank-detail { padding: 0 18px 18px 88px; border-top: 1px solid #eee9e2; }
.bank-detail ul { padding: 0; list-style: none; display: grid; gap: 6px; font-size: 13px; }
.bank-detail .answer-line { color: var(--green); font-weight: 700; }

.settings-grid { display: grid; grid-template-columns: 1fr 1fr; gap: 16px; }
.settings-card { padding: 23px; }
.settings-card h3 { margin: 0 0 8px; font-family: "Songti SC", serif; font-size: 20px; }
.settings-card p { margin: 0 0 18px; color: var(--muted); font-size: 12px; line-height: 1.6; }
.setting-row { display: flex; align-items: center; justify-content: space-between; gap: 12px; margin-top: 12px; }
.setting-row input { width: 90px; }
.button-row { display: flex; flex-wrap: wrap; gap: 9px; }
.data-note { margin-top: 18px; padding: 15px; border-radius: 12px; background: var(--green-soft); color: #275b48; font-size: 12px; line-height: 1.6; }

.toast { position: fixed; left: 50%; bottom: 28px; z-index: 100; max-width: min(90vw, 460px); transform: translate(-50%, 20px); opacity: 0; pointer-events: none; padding: 12px 17px; border-radius: 10px; background: #20252c; color: #fff; box-shadow: 0 10px 30px rgba(0,0,0,.25); font-size: 12px; transition: 180ms ease; }
.toast.show { opacity: 1; transform: translate(-50%, 0); }
.bottom-nav { display: none; }

@media (max-width: 1050px) {
  .app-shell { grid-template-columns: 210px minmax(0,1fr); }
  .main-area { padding-left: 28px; padding-right: 28px; }
  .mode-grid, .topic-grid { grid-template-columns: repeat(2, minmax(0,1fr)); }
  .quick-grid { grid-template-columns: repeat(2, minmax(0,1fr)); }
}

@media (max-width: 780px) {
  .app-shell { display: block; }
  .sidebar { display: none; }
  .main-area { padding: 0 15px 92px; }
  .topbar { min-height: 92px; }
  .topbar h1 { font-size: 25px; }
  .top-actions .icon-button { display: none; }
  .hero-grid, .split-grid, .practice-layout, .settings-grid { grid-template-columns: 1fr; }
  .goal-card { min-height: 220px; }
  .session-side { position: static; }
  .shortcut-card { display: none; }
  .stat-grid { grid-template-columns: repeat(2, 1fr); }
  .filters { grid-template-columns: 1fr; }
  .score-hero { grid-template-columns: 1fr; text-align: center; }
  .score-circle { margin: 0 auto; }
  .score-breakdown { justify-content: center; }
  .bottom-nav { position: fixed; z-index: 50; left: 0; right: 0; bottom: 0; min-height: 70px; padding: 7px 8px max(8px, env(safe-area-inset-bottom)); display: grid; grid-template-columns: repeat(5, 1fr); background: rgba(255,253,249,.96); border-top: 1px solid var(--line); backdrop-filter: blur(14px); }
  .bottom-nav button { border: 0; background: transparent; color: #85817b; display: grid; place-items: center; gap: 2px; cursor: pointer; }
  .bottom-nav button span { font-size: 19px; }
  .bottom-nav button small { font-size: 10px; }
  .bottom-nav button.active { color: var(--red); }
  .bank-item summary { grid-template-columns: 45px minmax(0,1fr); }
  .bank-item summary .status-tag { display: none; }
  .bank-detail { padding-left: 18px; }
}

@media (max-width: 520px) {
  .topbar { align-items: flex-end; padding: 17px 2px 14px; }
  .topbar p { font-size: 10px; }
  .topbar h1 { font-size: 22px; }
  .streak-pill { padding: 7px 9px; font-size: 10px; }
  .daily-card { min-height: 285px; padding: 25px 22px; }
  .daily-card h2 { font-size: 31px; }
  .quick-grid, .mode-grid, .topic-grid { grid-template-columns: 1fr; }
  .stat-card { padding: 15px; }
  .question-card { padding: 17px; }
  .question-title { margin-top: 20px; font-size: 20px; }
  .question-toolbar { align-items: flex-start; }
  .option-button { grid-template-columns: 31px minmax(0,1fr) 16px; padding: 11px; }
  .question-actions { display: grid; grid-template-columns: 1fr; }
  .question-actions > button, .action-right, .action-right > button { width: 100%; }
  .action-right { display: grid; grid-template-columns: 1fr 1.4fr; }
  .score-hero { padding: 24px; }
}

@media (prefers-reduced-motion: reduce) {
  *, *::before, *::after { scroll-behavior: auto !important; transition: none !important; }
}

/* Liquid glass visual system */
:root {
  --red: #c72736;
  --red-dark: #8d1723;
  --red-soft: rgba(255, 222, 225, 0.58);
  --ink: #1d2632;
  --muted: #687384;
  --line: rgba(255, 255, 255, 0.72);
  --paper: rgba(255, 255, 255, 0.56);
  --canvas: #edf4fa;
  --green-soft: rgba(214, 244, 231, 0.64);
  --amber-soft: rgba(255, 239, 194, 0.67);
  --blue-soft: rgba(215, 235, 255, 0.7);
  --shadow: 0 22px 55px rgba(61, 79, 99, 0.12), inset 0 1px 0 rgba(255, 255, 255, 0.86);
  --radius: 24px;
}

html { background: #edf4fa; }

body {
  min-height: 100vh;
  background:
    radial-gradient(circle at 8% 3%, rgba(183, 226, 255, 0.9), transparent 30%),
    radial-gradient(circle at 88% 18%, rgba(232, 206, 255, 0.72), transparent 31%),
    radial-gradient(circle at 46% 88%, rgba(192, 238, 219, 0.64), transparent 36%),
    linear-gradient(145deg, #f7fbff 0%, #edf3f8 46%, #f7f4fb 100%);
  background-attachment: fixed;
}

.ambient-light {
  position: fixed;
  inset: 0;
  z-index: -1;
  pointer-events: none;
  overflow: hidden;
}

.ambient-light i {
  position: absolute;
  width: 42vw;
  aspect-ratio: 1;
  border-radius: 50%;
  filter: blur(12px);
  opacity: 0.58;
  transform: translateZ(0);
}

.ambient-light i:nth-child(1) { left: -16vw; top: 8vh; background: radial-gradient(circle at 65% 35%, rgba(124, 203, 255, .74), rgba(178, 222, 255, .08) 68%); }
.ambient-light i:nth-child(2) { right: -14vw; top: 28vh; background: radial-gradient(circle at 35% 40%, rgba(210, 165, 255, .62), rgba(242, 218, 255, .08) 70%); }
.ambient-light i:nth-child(3) { left: 34vw; bottom: -24vw; background: radial-gradient(circle at 50% 30%, rgba(119, 218, 182, .52), rgba(211, 247, 232, .05) 72%); }

.app-shell { position: relative; isolation: isolate; }

.sidebar {
  background: linear-gradient(160deg, rgba(22, 29, 40, 0.87), rgba(31, 38, 50, 0.72));
  border-right: 1px solid rgba(255, 255, 255, 0.18);
  -webkit-backdrop-filter: saturate(160%) blur(32px);
  backdrop-filter: saturate(160%) blur(32px);
  box-shadow: 14px 0 45px rgba(36, 48, 61, 0.12), inset -1px 0 0 rgba(255,255,255,.08);
}

.brand-mark {
  background: linear-gradient(145deg, #e24e58, #ad1e2c 68%);
  border: 1px solid rgba(255,255,255,.3);
  box-shadow: 0 12px 26px rgba(184, 31, 44, 0.38), inset 0 1px 0 rgba(255,255,255,.42);
}

.side-nav button { border: 1px solid transparent; }
.side-nav button:hover { background: rgba(255,255,255,.08); border-color: rgba(255,255,255,.08); }
.side-nav button.active {
  background: linear-gradient(145deg, rgba(230, 55, 68, .92), rgba(175, 27, 42, .88));
  border-color: rgba(255,255,255,.22);
  box-shadow: 0 12px 30px rgba(150, 20, 33, 0.28), inset 0 1px 0 rgba(255,255,255,.28);
}

.offline-note { background: rgba(255,255,255,.045); -webkit-backdrop-filter: blur(20px); backdrop-filter: blur(20px); }

.surface,
.quick-card,
.option-button,
.field,
.select-field,
.streak-pill,
.icon-button {
  border-color: rgba(255, 255, 255, 0.76);
  background: linear-gradient(145deg, rgba(255,255,255,.7), rgba(255,255,255,.42));
  -webkit-backdrop-filter: saturate(165%) blur(28px);
  backdrop-filter: saturate(165%) blur(28px);
  box-shadow: var(--shadow), inset 0 -1px 0 rgba(255,255,255,.34);
}

.surface { position: relative; }
.topbar h1 { letter-spacing: -.025em; }

.streak-pill {
  border: 1px solid rgba(255,255,255,.8);
  color: #8f5f0c;
  box-shadow: 0 10px 28px rgba(61,79,99,.09), inset 0 1px 0 rgba(255,255,255,.9);
}

.icon-button { border: 1px solid rgba(255,255,255,.82); }

.daily-card {
  background:
    radial-gradient(circle at 88% 12%, rgba(255,255,255,.28), transparent 28%),
    linear-gradient(135deg, rgba(167, 23, 37, .96), rgba(210, 46, 59, .91) 58%, rgba(232, 105, 98, .88));
  border: 1px solid rgba(255,255,255,.34);
  box-shadow: 0 26px 65px rgba(142, 32, 45, .24), inset 0 1px 0 rgba(255,255,255,.36), inset 0 -1px 0 rgba(92,8,20,.12);
  -webkit-backdrop-filter: saturate(160%) blur(30px);
  backdrop-filter: saturate(160%) blur(30px);
}

.daily-card::before {
  width: 58%;
  height: 64%;
  right: -8%;
  top: -32%;
  border: 1px solid rgba(255,255,255,.24);
  background: radial-gradient(circle at 50% 100%, rgba(255,255,255,.18), transparent 65%);
  box-shadow: inset 0 -1px 0 rgba(255,255,255,.22);
}

.daily-card::after {
  width: 330px;
  height: 330px;
  right: -115px;
  bottom: -210px;
  border: 55px solid rgba(255,255,255,.07);
  box-shadow: 0 0 80px rgba(255,255,255,.07);
}

.daily-card .primary-button,
.daily-card .secondary-button {
  border: 1px solid rgba(255,255,255,.45);
  -webkit-backdrop-filter: blur(18px);
  backdrop-filter: blur(18px);
  box-shadow: 0 12px 30px rgba(89, 6, 18, .18), inset 0 1px 0 rgba(255,255,255,.45);
}

.daily-card .primary-button { background: linear-gradient(145deg, rgba(255,255,255,.95), rgba(255,255,255,.78)); }
.daily-card .secondary-button { background: linear-gradient(145deg, rgba(255,255,255,.22), rgba(255,255,255,.1)); }

.primary-button {
  border-color: rgba(255,255,255,.28);
  background: linear-gradient(145deg, #df3a49, #aa1d2b);
  box-shadow: 0 12px 28px rgba(177, 28, 42, .22), inset 0 1px 0 rgba(255,255,255,.32);
}

.primary-button:disabled,
.secondary-button:disabled,
.ghost-button:disabled {
  opacity: .42;
  cursor: not-allowed;
  transform: none;
  box-shadow: none;
}

.secondary-button { background: linear-gradient(145deg, rgba(42,53,68,.96), rgba(28,36,47,.92)); border-color: rgba(255,255,255,.18); }
.ghost-button { background: rgba(255,255,255,.34); border-color: rgba(255,255,255,.78); -webkit-backdrop-filter: blur(18px); backdrop-filter: blur(18px); box-shadow: 0 8px 24px rgba(61,79,99,.07), inset 0 1px 0 rgba(255,255,255,.86); }

.goal-ring { background: conic-gradient(#d62e3e var(--progress), rgba(146,161,176,.16) 0); box-shadow: 0 16px 35px rgba(79,98,118,.12), inset 0 1px 0 rgba(255,255,255,.8); }
.goal-ring::after { background: rgba(255,255,255,.66); -webkit-backdrop-filter: blur(14px); backdrop-filter: blur(14px); }

.quick-card,
.mode-card,
.topic-card { overflow: hidden; }

.quick-card::after,
.mode-card::after,
.topic-card::after {
  content: "";
  position: absolute;
  width: 75%;
  height: 58%;
  left: -16%;
  top: -30%;
  border-radius: 50%;
  background: radial-gradient(ellipse, rgba(255,255,255,.7), rgba(255,255,255,0) 70%);
  pointer-events: none;
}

.quick-card { position: relative; }
.quick-card:hover, .mode-card:hover, .topic-card:hover { border-color: rgba(255,255,255,.95); box-shadow: 0 26px 60px rgba(61,79,99,.15), inset 0 1px 0 rgba(255,255,255,.92); }
.quick-card .quick-icon, .mode-card .mode-icon { border: 1px solid rgba(255,255,255,.72); box-shadow: inset 0 1px 0 rgba(255,255,255,.8), 0 10px 22px rgba(70,89,110,.08); }

.progress-track { background: rgba(115,132,149,.13); box-shadow: inset 0 1px 2px rgba(54,68,83,.08); }
.progress-track i { background: linear-gradient(90deg, #e14a57, #b31d2c); box-shadow: 0 0 12px rgba(198, 39, 54, .26); }

.option-button {
  border: 1px solid rgba(255,255,255,.78);
  box-shadow: 0 10px 28px rgba(61,79,99,.07), inset 0 1px 0 rgba(255,255,255,.92);
}

.option-button:hover:not(:disabled) { border-color: rgba(255,255,255,.98); background: rgba(255,255,255,.76); box-shadow: 0 14px 32px rgba(61,79,99,.11), inset 0 1px 0 #fff; }
.option-key { border: 1px solid rgba(255,255,255,.74); background: rgba(230,236,242,.7); box-shadow: inset 0 1px 0 rgba(255,255,255,.9); }
.option-button.selected { border-color: rgba(204,44,58,.58); background: linear-gradient(145deg, rgba(255,237,238,.88), rgba(255,220,224,.54)); box-shadow: 0 12px 30px rgba(186,35,49,.11), inset 0 1px 0 rgba(255,255,255,.92); }
.option-button.correct { border-color: rgba(55,145,105,.46); background: linear-gradient(145deg, rgba(235,255,246,.9), rgba(205,242,224,.62)); }
.option-button.wrong { border-color: rgba(201,51,63,.45); background: linear-gradient(145deg, rgba(255,240,241,.9), rgba(255,215,220,.62)); }

.feedback { background: linear-gradient(145deg, rgba(255,255,255,.68), rgba(240,249,245,.54)); border-top: 1px solid rgba(255,255,255,.86); border-right: 1px solid rgba(255,255,255,.7); border-bottom: 1px solid rgba(255,255,255,.7); box-shadow: inset 0 1px 0 rgba(255,255,255,.86); }
.short-answer-box { background: rgba(255,255,255,.4); border-color: rgba(255,255,255,.85); -webkit-backdrop-filter: blur(18px); backdrop-filter: blur(18px); }

.exam-bar { -webkit-backdrop-filter: saturate(180%) blur(30px); backdrop-filter: saturate(180%) blur(30px); }
.exam-grid button { border-color: rgba(255,255,255,.76); background: rgba(255,255,255,.48); box-shadow: inset 0 1px 0 rgba(255,255,255,.9); }

.toast { background: rgba(23,30,40,.78); border: 1px solid rgba(255,255,255,.22); -webkit-backdrop-filter: saturate(180%) blur(24px); backdrop-filter: saturate(180%) blur(24px); box-shadow: 0 16px 45px rgba(29,39,51,.28), inset 0 1px 0 rgba(255,255,255,.2); }

@supports not ((-webkit-backdrop-filter: blur(1px)) or (backdrop-filter: blur(1px))) {
  .surface, .quick-card, .option-button, .field, .select-field, .bottom-nav { background: rgba(248, 251, 254, .96); }
}

@media (max-width: 780px) {
  body { background-attachment: scroll; }

  .ambient-light i { width: 82vw; opacity: .5; }
  .ambient-light i:nth-child(1) { left: -38vw; top: 5vh; }
  .ambient-light i:nth-child(2) { right: -42vw; top: 38vh; }
  .ambient-light i:nth-child(3) { left: 5vw; bottom: -30vw; }

  .main-area { padding: 0 12px 112px; }

  .topbar {
    position: sticky;
    top: 0;
    z-index: 35;
    min-height: 88px;
    margin: 0 -12px 12px;
    padding: max(15px, env(safe-area-inset-top)) 16px 14px;
    align-items: flex-end;
    background: linear-gradient(180deg, rgba(246,250,254,.84), rgba(246,250,254,.56));
    border-bottom: 1px solid rgba(255,255,255,.76);
    -webkit-backdrop-filter: saturate(180%) blur(30px);
    backdrop-filter: saturate(180%) blur(30px);
    box-shadow: 0 12px 34px rgba(72,91,111,.08), inset 0 -1px 0 rgba(255,255,255,.55);
  }

  .topbar p { margin-bottom: 5px; letter-spacing: .1em; }
  .topbar h1 { max-width: 245px; font-size: 23px; line-height: 1.15; }
  .streak-pill { margin-bottom: 1px; }

  .hero-grid { gap: 12px; }
  .daily-card { min-height: 270px; padding: 27px 23px; border-radius: 28px; }
  .daily-card h2 { max-width: 300px; margin-top: 17px; font-size: 34px; line-height: 1.15; }
  .daily-card p { font-size: 13px; line-height: 1.65; }
  .hero-actions { margin-top: 21px; gap: 8px; }
  .daily-card .primary-button, .daily-card .secondary-button { min-height: 46px; border-radius: 14px; padding: 0 15px; }

  .goal-card { min-height: 205px; padding: 20px 21px; border-radius: 26px; }
  .goal-ring { width: 96px; height: 96px; }
  .goal-ring::after { width: 72px; height: 72px; }
  .goal-ring strong { font-size: 23px; }
  .goal-ring small { padding-top: 28px; }

  .stat-grid { gap: 10px; }
  .stat-card { min-height: 116px; border-radius: 22px; }
  .stat-card strong { font-size: 25px; }

  .quick-grid { grid-template-columns: repeat(2, minmax(0,1fr)); gap: 10px; }
  .quick-card { min-height: 156px; padding: 16px; border-radius: 22px; }
  .quick-card .quick-icon { width: 36px; height: 36px; margin-bottom: 14px; border-radius: 12px; }
  .quick-card small { font-size: 11px; }

  .mode-card, .topic-card { border-radius: 25px; }
  .panel { border-radius: 25px; }

  .practice-layout { gap: 12px; }
  .question-card { border-radius: 28px; padding: 20px 17px; }
  .question-toolbar { padding-bottom: 15px; }
  .question-title { margin: 20px 0; font-size: 21px; line-height: 1.62; letter-spacing: -.01em; }
  .option-list { gap: 10px; }
  .option-button { min-height: 62px; border-radius: 18px; padding: 11px 12px; }
  .option-key { width: 34px; height: 34px; border-radius: 11px; }
  .question-actions { margin-top: 18px; }
  .question-actions .primary-button, .question-actions .ghost-button { min-height: 48px; border-radius: 15px; }
  .feedback { border-radius: 18px; padding: 18px; }

  .session-progress { border-radius: 24px; padding: 17px; }
  .exam-grid { grid-template-columns: repeat(8, minmax(30px, 1fr)); gap: 6px; }
  .exam-grid button { border-radius: 10px; font-size: 10px; }

  .exam-bar { position: sticky; top: 99px; z-index: 24; margin-bottom: 12px; border-radius: 21px; padding: 12px 14px; }
  .exam-timer { font-size: 19px; }

  .filters { border-radius: 23px; padding: 12px; }
  .field, .select-field { min-height: 48px; border-radius: 15px; }
  .bank-item { border-radius: 20px; }

  .bottom-nav {
    left: 10px;
    right: 10px;
    bottom: max(9px, env(safe-area-inset-bottom));
    min-height: 72px;
    padding: 7px 6px;
    border: 1px solid rgba(255,255,255,.78);
    border-radius: 27px;
    background: linear-gradient(145deg, rgba(255,255,255,.72), rgba(244,249,253,.48));
    -webkit-backdrop-filter: saturate(190%) blur(34px);
    backdrop-filter: saturate(190%) blur(34px);
    box-shadow: 0 22px 60px rgba(53,73,94,.22), inset 0 1px 0 rgba(255,255,255,.94), inset 0 -1px 0 rgba(255,255,255,.4);
  }

  .bottom-nav button { position: relative; min-width: 0; border-radius: 19px; overflow: hidden; }
  .bottom-nav button::before {
    content: "";
    position: absolute;
    inset: 2px 4px;
    border-radius: 17px;
    opacity: 0;
    background: linear-gradient(145deg, rgba(255,226,229,.86), rgba(255,255,255,.44));
    border: 1px solid rgba(255,255,255,.72);
    box-shadow: 0 8px 18px rgba(174,35,48,.09), inset 0 1px 0 rgba(255,255,255,.92);
    transition: 180ms ease;
  }
  .bottom-nav button.active::before { opacity: 1; }
  .bottom-nav button span, .bottom-nav button small { position: relative; z-index: 1; }
  .bottom-nav button.active { color: #b51f2d; }

  .toast { bottom: 96px; border-radius: 17px; }
}

@media (max-width: 520px) {
  .quick-grid { grid-template-columns: repeat(2, minmax(0,1fr)); }
  .mode-grid, .topic-grid { grid-template-columns: 1fr; }
  .score-hero { border-radius: 28px; }
  .score-circle { box-shadow: 0 20px 45px rgba(182,40,53,.15), inset 0 1px 0 rgba(255,255,255,.8); }
  .question-actions {
    position: sticky;
    bottom: 91px;
    z-index: 18;
    display: flex;
    flex-wrap: nowrap;
    align-items: stretch;
    margin: 17px -7px -5px;
    padding: 7px;
    border: 1px solid rgba(255,255,255,.78);
    border-radius: 20px;
    background: linear-gradient(145deg, rgba(255,255,255,.76), rgba(245,250,253,.52));
    -webkit-backdrop-filter: saturate(180%) blur(26px);
    backdrop-filter: saturate(180%) blur(26px);
    box-shadow: 0 14px 35px rgba(61,79,99,.14), inset 0 1px 0 rgba(255,255,255,.95);
  }
  .question-actions > button { width: auto; flex: 0 0 106px; }
  .question-actions .action-right { width: auto; flex: 1; display: flex; }
  .question-actions .action-right > button { width: 100%; flex: 1; }
}

/* ============ Multi-bank extension（多题库扩展样式） ============ */
.bank-bar {
  max-width: 1220px;
  margin: -6px auto 18px;
  padding: 0 2px 6px;
  display: flex;
  gap: 9px;
  overflow-x: auto;
  scrollbar-width: none;
}
.bank-bar::-webkit-scrollbar { display: none; }

.bank-chip {
  flex: 0 0 auto;
  display: inline-flex;
  align-items: baseline;
  gap: 7px;
  min-height: 38px;
  padding: 0 16px;
  border-radius: 999px;
  border: 1px solid rgba(255,255,255,.8);
  background: linear-gradient(145deg, rgba(255,255,255,.66), rgba(255,255,255,.4));
  -webkit-backdrop-filter: saturate(160%) blur(24px);
  backdrop-filter: saturate(160%) blur(24px);
  box-shadow: 0 8px 22px rgba(61,79,99,.08), inset 0 1px 0 rgba(255,255,255,.9);
  cursor: pointer;
  transition: 150ms ease;
  color: var(--ink);
}
.bank-chip b { font-size: 13px; letter-spacing: .02em; }
.bank-chip small { color: var(--muted); font-size: 11px; }
.bank-chip:hover { transform: translateY(-1px); box-shadow: 0 12px 28px rgba(61,79,99,.13), inset 0 1px 0 rgba(255,255,255,.95); }
.bank-chip.active {
  background: linear-gradient(145deg, var(--chip), color-mix(in srgb, var(--chip) 78%, #000));
  border-color: rgba(255,255,255,.35);
  color: #fff;
  box-shadow: 0 12px 28px color-mix(in srgb, var(--chip) 32%, transparent), inset 0 1px 0 rgba(255,255,255,.3);
}
.bank-chip.active small { color: rgba(255,255,255,.75); }

.bank-tag {
  display: inline-flex;
  align-items: center;
  min-height: 22px;
  padding: 0 8px;
  border-radius: 999px;
  font-size: 10px;
  font-weight: 700;
  color: var(--chip, #315f87);
  background: color-mix(in srgb, var(--chip, #315f87) 10%, rgba(255,255,255,.85));
  border: 1px solid color-mix(in srgb, var(--chip, #315f87) 32%, rgba(255,255,255,.6));
}

.history-chip {
  display: inline-flex;
  align-items: center;
  min-height: 22px;
  padding: 0 9px;
  border-radius: 999px;
  background: rgba(115,132,149,.12);
  color: #5c6675;
  font-size: 10px;
  font-weight: 600;
  white-space: nowrap;
}

.diff-tag { background: var(--amber-soft); color: var(--amber); }
.diff-tag.diff-easy { background: var(--green-soft); color: var(--green); }
.diff-tag.diff-hard { background: var(--red-soft); color: var(--red); }

.question-toolbar-right { display: flex; align-items: center; gap: 9px; flex-wrap: wrap; justify-content: flex-end; }

/* 解析面板：正确答案 / 依据出处 / 无解析提示 / 相似题 */
.feedback .answer-line { color: var(--green); font-weight: 700; }
.feedback .source-line { margin-top: 12px; padding-top: 12px; border-top: 1px dashed #cfd8e2; color: #5c6675; font-size: 12px; }
.analysis-gap {
  margin-top: 12px;
  padding: 13px 15px;
  border-radius: 12px;
  background: var(--amber-soft);
  display: flex;
  align-items: center;
  gap: 12px;
  flex-wrap: wrap;
}
.analysis-gap p { margin: 0; flex: 1; min-width: 200px; color: #6a5416; font-size: 12px; line-height: 1.6; }
.text-link { border: 0; background: transparent; padding: 0; margin-top: 12px; display: inline-block; color: var(--red); font-size: 12px; font-weight: 700; cursor: pointer; }
.text-link:hover { text-decoration: underline; }

.similar-strip { margin-top: 15px; padding-top: 13px; border-top: 1px dashed #cfd8e2; display: grid; gap: 8px; }
.similar-strip > strong { font-size: 12px; letter-spacing: .06em; color: var(--ink); }
.similar-strip.inline { border-top: 0; padding-top: 4px; margin-top: 12px; }
.similar-item {
  width: 100%;
  display: flex;
  align-items: center;
  gap: 9px;
  padding: 9px 12px;
  border: 1px solid rgba(255,255,255,.78);
  border-radius: 12px;
  background: linear-gradient(145deg, rgba(255,255,255,.6), rgba(255,255,255,.34));
  cursor: pointer;
  text-align: left;
  font-size: 12px;
  line-height: 1.5;
  transition: 140ms ease;
}
.similar-item:hover { transform: translateY(-1px); box-shadow: 0 10px 24px rgba(61,79,99,.12), inset 0 1px 0 rgba(255,255,255,.92); }
.similar-item > span { flex: 1; min-width: 0; overflow: hidden; text-overflow: ellipsis; white-space: nowrap; color: var(--ink); }
.similar-note { margin: 2px 0 0; color: var(--muted); font-size: 11px; }

/* 首页题库总览卡片 */
.bank-overview { display: grid; grid-template-columns: repeat(3, minmax(0,1fr)); gap: 14px; }
.bank-card { padding: 20px; cursor: pointer; text-align: left; transition: 160ms ease; display: grid; gap: 13px; }
.bank-card:hover { transform: translateY(-2px); box-shadow: 0 26px 60px rgba(61,79,99,.15), inset 0 1px 0 rgba(255,255,255,.92); }
.bank-card-head { display: flex; align-items: center; gap: 12px; }
.bank-mark {
  width: 42px; height: 42px; flex: 0 0 auto;
  border-radius: 13px;
  display: grid; place-items: center;
  font-family: "Songti SC", serif;
  font-size: 14px; font-weight: 700; color: #fff;
  background: linear-gradient(145deg, color-mix(in srgb, var(--chip) 86%, #fff), var(--chip));
  border: 1px solid rgba(255,255,255,.4);
  box-shadow: 0 10px 22px color-mix(in srgb, var(--chip) 30%, transparent), inset 0 1px 0 rgba(255,255,255,.4);
}
.bank-card-head strong { display: block; font-size: 15px; }
.bank-card-head small { display: block; margin-top: 3px; color: var(--muted); font-size: 11px; }
.bank-card-foot { display: flex; justify-content: space-between; align-items: center; color: var(--muted); font-size: 11px; }
.bank-card .arrow { color: var(--chip); font-size: 17px; }
.bank-card .progress-track i { background: linear-gradient(90deg, color-mix(in srgb, var(--chip) 78%, #fff), var(--chip)); }

/* 错题：易错点聚类卡片 */
.cluster-grid { display: grid; grid-template-columns: repeat(2, minmax(0,1fr)); gap: 14px; }
.cluster-card { padding: 21px; }
.cluster-head { display: flex; align-items: center; gap: 11px; flex-wrap: wrap; margin-bottom: 10px; }
.cluster-phrase { font-family: "Songti SC", serif; font-size: 21px; font-weight: 700; color: var(--red); }
.cluster-phrase::before { content: "「"; color: #e5a3a8; }
.cluster-phrase::after { content: "」"; color: #e5a3a8; }
.cluster-count { display: inline-flex; min-height: 24px; align-items: center; padding: 0 10px; border-radius: 999px; background: var(--red-soft); color: var(--red); font-size: 10px; font-weight: 700; }
.cluster-advice { margin: 0 0 13px; color: #4a5462; font-size: 12px; line-height: 1.75; }
.cluster-q { display: grid; gap: 8px; }
.cluster-related { margin-top: 11px; }
.cluster-related summary { cursor: pointer; font-size: 12px; font-weight: 700; color: var(--blue); list-style: none; }
.cluster-related summary::-webkit-details-marker { display: none; }
.cluster-related[open] summary { margin-bottom: 1px; }
.cluster-related > .similar-item { margin-top: 8px; }

/* 题库列表项：题库标签 + 历史 */
.bank-item summary { grid-template-columns: auto minmax(0,1fr) auto; gap: 12px; }
.bank-item-meta { display: flex; align-items: center; gap: 8px; }
.bank-detail { padding-left: 20px; }
.short-answer-text { white-space: pre-line; }
.bank-item-actions { margin-top: 13px; }

/* AI 问答界面 */
.ai-layout { display: grid; grid-template-columns: minmax(0,1fr) 308px; gap: 18px; align-items: start; }
.ai-chat { display: flex; flex-direction: column; min-height: 580px; overflow: hidden; }
.ai-topbar { padding: 13px 18px; display: flex; justify-content: space-between; align-items: center; gap: 10px; flex-wrap: wrap; border-bottom: 1px solid rgba(255,255,255,.66); }
.ai-context { display: inline-flex; align-items: center; gap: 8px; max-width: 100%; min-height: 32px; padding: 0 12px; border-radius: 999px; background: rgba(255,255,255,.5); border: 1px solid rgba(255,255,255,.78); font-size: 12px; }
.ai-context > span { max-width: 300px; overflow: hidden; text-overflow: ellipsis; white-space: nowrap; }
.ai-context.none { color: var(--muted); font-size: 11px; }
.chip-close { border: 0; background: transparent; cursor: pointer; color: var(--muted); font-size: 15px; line-height: 1; padding: 2px; }
.chip-close:hover { color: var(--red); }
.ai-messages { flex: 1; min-height: 300px; max-height: 58vh; overflow-y: auto; padding: 20px; display: grid; gap: 13px; align-content: start; }
.ai-msg { max-width: 88%; }
.ai-msg.user { justify-self: end; }
.ai-msg.assistant { justify-self: start; max-width: 94%; }
.ai-bubble { padding: 12px 16px; border-radius: 17px; font-size: 13px; line-height: 1.8; word-break: break-word; }
.ai-msg.user .ai-bubble {
  background: linear-gradient(145deg, #df3a49, #aa1d2b);
  color: #fff;
  border-bottom-right-radius: 6px;
  box-shadow: 0 10px 24px rgba(177,28,42,.2), inset 0 1px 0 rgba(255,255,255,.3);
}
.ai-msg.assistant .ai-bubble {
  background: linear-gradient(145deg, rgba(255,255,255,.82), rgba(255,255,255,.58));
  border: 1px solid rgba(255,255,255,.85);
  border-bottom-left-radius: 6px;
  box-shadow: 0 10px 26px rgba(61,79,99,.08), inset 0 1px 0 rgba(255,255,255,.9);
}
.ai-bubble pre { margin: 8px 0; padding: 10px 12px; border-radius: 10px; background: rgba(29,38,50,.07); font-size: 12px; white-space: pre-wrap; }
.ai-bubble code { padding: 1px 5px; border-radius: 6px; background: rgba(29,38,50,.08); font-size: 12px; }
.ai-empty { margin: auto 0; }
.ai-setup-hint { color: #8f5f0c; font-weight: 700; }
.ai-quick { padding: 0 18px 11px; display: flex; gap: 8px; flex-wrap: wrap; }
.quick-chip {
  padding: 7px 14px;
  border-radius: 999px;
  border: 1px solid rgba(255,255,255,.82);
  background: linear-gradient(145deg, rgba(255,255,255,.6), rgba(255,255,255,.34));
  color: #4a5462;
  font-size: 12px;
  cursor: pointer;
  transition: 140ms ease;
}
.quick-chip:hover { transform: translateY(-1px); color: var(--red); border-color: rgba(204,44,58,.4); box-shadow: 0 8px 20px rgba(186,35,49,.1); }
.ai-composer { padding: 13px 18px 17px; display: grid; grid-template-columns: minmax(0,1fr) auto auto; gap: 9px; align-items: end; border-top: 1px solid rgba(255,255,255,.66); }
#ai-input {
  width: 100%;
  min-height: 46px;
  max-height: 140px;
  resize: none;
  padding: 11px 14px;
  border: 1px solid rgba(255,255,255,.8);
  border-radius: 14px;
  background: rgba(255,255,255,.6);
  outline: none;
  line-height: 1.6;
}
#ai-input:focus { border-color: var(--red); box-shadow: 0 0 0 3px rgba(180,35,42,.08); }
.ai-stop { color: var(--red); border-color: #efc8c8; }
.ai-side { display: grid; gap: 14px; position: sticky; top: 18px; }
.ai-settings { padding: 21px; }
.ai-settings h3 { margin: 0 0 9px; font-family: "Songti SC", serif; font-size: 17px; display: flex; align-items: center; }
.ai-settings p { margin: 0 0 13px; color: var(--muted); font-size: 12px; line-height: 1.65; }
.setting-row.column { flex-direction: column; align-items: stretch; gap: 6px; margin-top: 11px; }
.setting-row.column span { font-size: 12px; color: var(--muted); }
.conn-dot { width: 8px; height: 8px; border-radius: 50%; background: #c4ccd4; display: inline-block; margin: 0 7px 0 4px; }
.conn-dot.on { background: #5ac18e; box-shadow: 0 0 0 4px rgba(90,193,142,.15); }
.typing-dots i { width: 6px; height: 6px; border-radius: 50%; background: var(--muted); display: inline-block; margin-right: 4px; animation: typing 1.2s infinite; }
.typing-dots i:nth-child(2) { animation-delay: .18s; }
.typing-dots i:nth-child(3) { animation-delay: .36s; }
@keyframes typing { 0%, 80%, 100% { opacity: .25; transform: translateY(0); } 40% { opacity: 1; transform: translateY(-2px); } }

@media (max-width: 1050px) {
  .bank-overview { grid-template-columns: repeat(2, minmax(0,1fr)); }
  .ai-layout { grid-template-columns: 1fr; }
  .ai-side { position: static; }
  .ai-messages { max-height: 52vh; }
}

@media (max-width: 780px) {
  .bottom-nav { grid-template-columns: repeat(6, 1fr); }
  .bank-bar { margin: -2px 0 14px; }
  .bank-overview, .cluster-grid { grid-template-columns: 1fr; }
  .bank-item-meta .history-chip { display: none; }
  .ai-chat { min-height: 520px; }
  .ai-messages { max-height: 46vh; padding: 15px; }
  .ai-composer { grid-template-columns: minmax(0,1fr) auto; padding: 11px 13px 14px; }
  .ai-stop { grid-column: 2; }
  .ai-context > span { max-width: 170px; }
}

/* ============ 交互增强（点击即判、续答、及格线） ============ */
.auto-hint {
  display: inline-flex;
  align-items: center;
  min-height: 42px;
  padding: 0 6px;
  color: var(--muted);
  font-size: 12px;
  letter-spacing: .02em;
}

.resume-banner {
  margin-bottom: 16px;
  padding: 18px 22px;
  display: flex;
  justify-content: space-between;
  align-items: center;
  gap: 16px;
  flex-wrap: wrap;
  border-left: 4px solid var(--red);
}
.resume-banner strong { font-family: "Songti SC", serif; font-size: 17px; color: var(--ink); }
.resume-banner p { margin: 5px 0 0; color: var(--muted); font-size: 12px; }

.pass-badge {
  display: inline-block;
  margin-top: 6px;
  padding: 4px 12px;
  border-radius: 999px;
  font-size: 12px;
  font-weight: 700;
}
.pass-badge.pass { background: var(--green-soft); color: var(--green); }
.pass-badge.fail { background: var(--red-soft); color: var(--red); }