/* ============================================================
   新课标学习系统 · 苹果毛玻璃风格
   ============================================================ */
:root {
  --blue: #0a84ff;
  --blue-dark: #0071e3;
  --text: #1d1d1f;
  --text-2: #6e6e73;
  --glass-bg: rgba(255, 255, 255, 0.55);
  --glass-border: rgba(255, 255, 255, 0.65);
  --shadow: 0 8px 32px rgba(31, 38, 135, 0.12);
  --radius: 22px;
  --green: #34c759;
  --red: #ff3b30;
  --orange: #ff9f0a;
}

* { margin: 0; padding: 0; box-sizing: border-box; }

html, body { height: 100%; }

body {
  font-family: -apple-system, BlinkMacSystemFont, "SF Pro Text", "PingFang SC",
    "Helvetica Neue", "Microsoft YaHei", sans-serif;
  color: var(--text);
  background: linear-gradient(135deg, #e3f2ff 0%, #f0e8ff 40%, #ffe8f2 75%, #e8fbff 100%);
  min-height: 100vh;
  overflow-x: hidden;
  line-height: 1.6;
}

/* ---------- 背景光斑 ---------- */
.bg-blobs { position: fixed; inset: 0; z-index: -1; overflow: hidden; }
.blob {
  position: absolute;
  border-radius: 50%;
  filter: blur(90px);
  opacity: 0.55;
  animation: float 18s ease-in-out infinite;
}
.blob-1 { width: 480px; height: 480px; background: #7bb8ff; top: -120px; left: -80px; }
.blob-2 { width: 420px; height: 420px; background: #c4a5ff; top: 30%; right: -140px; animation-delay: -4s; }
.blob-3 { width: 380px; height: 380px; background: #ffa8d0; bottom: -100px; left: 20%; animation-delay: -8s; }
.blob-4 { width: 300px; height: 300px; background: #9be8ff; bottom: 10%; right: 20%; animation-delay: -12s; }

@keyframes float {
  0%, 100% { transform: translate(0, 0) scale(1); }
  33%      { transform: translate(30px, -30px) scale(1.08); }
  66%      { transform: translate(-20px, 20px) scale(0.95); }
}

/* ---------- 毛玻璃卡片 ---------- */
.glass-card {
  background: var(--glass-bg);
  -webkit-backdrop-filter: blur(24px) saturate(180%);
  backdrop-filter: blur(24px) saturate(180%);
  border: 1px solid var(--glass-border);
  border-radius: var(--radius);
  box-shadow: var(--shadow);
}

/* ---------- 导航栏 ---------- */
.glass-nav {
  position: sticky;
  top: 0;
  z-index: 50;
  background: rgba(255, 255, 255, 0.45);
  -webkit-backdrop-filter: blur(30px) saturate(180%);
  backdrop-filter: blur(30px) saturate(180%);
  border-bottom: 1px solid rgba(255, 255, 255, 0.55);
}
.nav-inner {
  max-width: 1100px;
  margin: 0 auto;
  padding: 12px 24px;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 16px;
}
.brand {
  display: flex;
  align-items: center;
  gap: 10px;
  font-weight: 700;
  font-size: 17px;
  color: var(--text);
  text-decoration: none;
}
.brand-icon {
  width: 34px; height: 34px;
  display: grid; place-items: center;
  font-size: 18px;
  border-radius: 10px;
  background: linear-gradient(135deg, #0a84ff, #7d5fff);
  color: #fff;
  box-shadow: 0 4px 12px rgba(10, 132, 255, 0.35);
}
.nav-links { display: flex; align-items: center; gap: 18px; font-size: 14px; }
.nav-links a { color: var(--text); text-decoration: none; transition: opacity .2s; }
.nav-links a:hover { opacity: 0.65; }
.nav-user { color: var(--text-2); }

/* ---------- 布局 ---------- */
.container { max-width: 1100px; margin: 0 auto; padding: 28px 24px 80px; }

.hero { padding: 32px 36px; margin-bottom: 32px; }
.hero h1 { font-size: 30px; font-weight: 700; letter-spacing: -0.5px; }
.hero p { color: var(--text-2); margin: 8px 0 18px; }

.section-head {
  display: flex; align-items: center; justify-content: space-between;
  margin: 8px 0 18px;
}
.section-head h1, .section-head h2 { font-size: 24px; font-weight: 700; }
.head-actions { display: flex; gap: 10px; }

/* ---------- 按钮 ---------- */
.btn {
  display: inline-flex; align-items: center; justify-content: center; gap: 6px;
  border: none; cursor: pointer;
  font-size: 14px; font-weight: 600;
  border-radius: 980px;
  padding: 10px 22px;
  text-decoration: none;
  transition: transform .15s ease, box-shadow .2s ease, opacity .2s;
  font-family: inherit;
}
.btn:hover { transform: translateY(-1px); }
.btn:active { transform: scale(0.97); }
.btn-primary {
  background: linear-gradient(135deg, var(--blue), #5e9bff);
  color: #fff;
  box-shadow: 0 6px 18px rgba(10, 132, 255, 0.35);
}
.btn-primary:hover { box-shadow: 0 8px 24px rgba(10, 132, 255, 0.45); }
.btn-outline {
  background: rgba(255, 255, 255, 0.6);
  color: var(--blue-dark);
  border: 1px solid rgba(10, 132, 255, 0.4);
}
.btn-ghost { background: rgba(255, 255, 255, 0.5); color: var(--text); }
.btn-danger { background: rgba(255, 59, 48, 0.12); color: var(--red); border: 1px solid rgba(255, 59, 48, 0.35); }
.btn-block { width: 100%; }
.btn-lg { padding: 13px 34px; font-size: 15px; }
.btn-sm { padding: 7px 16px; font-size: 13px; }
.btn-xs { padding: 5px 12px; font-size: 12px; }

/* ---------- 表单 ---------- */
.form { display: flex; flex-direction: column; gap: 16px; }
.grid-2 { display: grid; grid-template-columns: 1fr 1fr; gap: 16px; }
.span-2 { grid-column: 1 / -1; }
.field label { display: block; font-size: 13px; font-weight: 600; color: var(--text-2); margin-bottom: 6px; }
.field input, .field select {
  width: 100%;
  padding: 12px 16px;
  font-size: 15px;
  font-family: inherit;
  color: var(--text);
  background: rgba(255, 255, 255, 0.65);
  border: 1px solid rgba(255, 255, 255, 0.8);
  border-radius: 14px;
  outline: none;
  transition: box-shadow .2s, border-color .2s;
  -webkit-backdrop-filter: blur(10px);
  backdrop-filter: blur(10px);
}
.field input:focus, .field select:focus {
  border-color: var(--blue);
  box-shadow: 0 0 0 4px rgba(10, 132, 255, 0.18);
}

/* ---------- 认证页 ---------- */
.auth-wrap {
  display: grid; place-items: center;
  min-height: calc(100vh - 160px);
}
.auth-card { width: 100%; max-width: 400px; padding: 40px 36px; text-align: center; }
.auth-icon {
  width: 68px; height: 68px; margin: 0 auto 16px;
  display: grid; place-items: center; font-size: 34px;
  border-radius: 20px;
  background: linear-gradient(135deg, #0a84ff, #7d5fff);
  box-shadow: 0 10px 30px rgba(10, 132, 255, 0.35);
}
.auth-title { font-size: 26px; font-weight: 700; letter-spacing: -0.5px; }
.auth-sub { color: var(--text-2); font-size: 14px; margin: 6px 0 24px; }
.auth-card .form { text-align: left; }
.auth-switch { margin-top: 22px; font-size: 14px; color: var(--text-2); }
.auth-switch a { color: var(--blue-dark); text-decoration: none; font-weight: 600; }

/* ---------- 学科卡片 ---------- */
.subject-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(250px, 1fr));
  gap: 22px;
}
.subject-card { padding: 24px; display: flex; flex-direction: column; transition: transform .2s, box-shadow .2s; }
.subject-card:hover { transform: translateY(-4px); box-shadow: 0 14px 40px rgba(31, 38, 135, 0.18); }
.subject-top { display: flex; justify-content: space-between; align-items: center; margin-bottom: 12px; }
.subject-code {
  font-size: 12px; font-weight: 700; letter-spacing: 1px;
  color: var(--blue-dark);
  background: rgba(10, 132, 255, 0.12);
  padding: 4px 10px; border-radius: 8px;
}
.subject-name { font-size: 20px; font-weight: 700; }
.subject-desc { color: var(--text-2); font-size: 13px; margin: 6px 0 18px; flex: 1; }
.subject-foot { display: flex; align-items: center; justify-content: space-between; gap: 10px; }
.subject-btns { display: flex; gap: 8px; flex-wrap: wrap; }
.remain { font-size: 13px; color: var(--green); font-weight: 600; }
.remain.muted { color: var(--text-2); font-weight: 400; }

/* ---------- 课标识别文本查看 ---------- */
.content-panel { padding: 10px 12px; max-height: 70vh; overflow-y: auto; }
.content-text {
  font-family: "PingFang SC", "Microsoft YaHei", sans-serif;
  font-size: 14px;
  line-height: 2;
  white-space: pre-wrap;
  word-break: break-all;
  color: var(--text);
}
.content-meta { padding: 14px 24px; margin-bottom: 16px; }
.info-card { padding: 16px 24px; margin-bottom: 20px; }

/* 状态徽章 */
.badge {
  font-size: 12px; font-weight: 600;
  padding: 4px 10px; border-radius: 980px;
}
.badge-active  { background: rgba(52, 199, 89, 0.15); color: #248a3d; }
.badge-expired { background: rgba(255, 159, 10, 0.16); color: #c25e00; }
.badge-none    { background: rgba(110, 110, 115, 0.12); color: var(--text-2); }

/* ---------- 提示消息 ---------- */
.flash-stack { position: fixed; top: 80px; right: 24px; z-index: 200; display: flex; flex-direction: column; gap: 10px; }
.flash {
  padding: 12px 20px;
  border-radius: 14px;
  font-size: 14px;
  box-shadow: 0 10px 30px rgba(0,0,0,0.12);
  background: rgba(255,255,255,0.75);
  -webkit-backdrop-filter: blur(20px);
  backdrop-filter: blur(20px);
  border: 1px solid rgba(255,255,255,0.7);
  animation: slideIn .35s ease;
  max-width: 360px;
}
.flash-success { border-left: 4px solid var(--green); }
.flash-error   { border-left: 4px solid var(--red); }
@keyframes slideIn { from { opacity: 0; transform: translateX(30px); } to { opacity: 1; transform: none; } }

/* ---------- 弹窗 ---------- */
.modal-overlay {
  position: fixed; inset: 0; z-index: 100;
  background: rgba(20, 20, 30, 0.25);
  -webkit-backdrop-filter: blur(8px);
  backdrop-filter: blur(8px);
  display: none;
  place-items: center;
  padding: 20px;
}
.modal-overlay.open { display: grid; }
.modal-card { position: relative; width: 100%; max-width: 420px; padding: 34px 32px; }
.modal-close {
  position: absolute; top: 16px; right: 16px;
  width: 30px; height: 30px;
  border: none; border-radius: 50%;
  background: rgba(0,0,0,0.06);
  color: var(--text-2);
  font-size: 14px; cursor: pointer;
}
.modal-close:hover { background: rgba(0,0,0,0.12); }
.modal-title { font-size: 20px; font-weight: 700; }

/* ---------- 练习页 ---------- */
.practice-head { display: flex; align-items: center; justify-content: space-between; }
.toolbar { padding: 16px 24px; margin-bottom: 22px; }
.toolbar-form { display: flex; align-items: flex-end; gap: 18px; flex-wrap: wrap; }
.toolbar-form label { font-size: 13px; font-weight: 600; color: var(--text-2); }
.toolbar-form select {
  margin-left: 8px;
  padding: 8px 12px; font-family: inherit; font-size: 14px;
  background: rgba(255,255,255,0.7);
  border: 1px solid rgba(255,255,255,0.8);
  border-radius: 10px; outline: none;
}
.question-card { padding: 24px 28px; margin-bottom: 18px; }
.q-head { display: flex; justify-content: space-between; margin-bottom: 12px; }
.q-no { font-weight: 700; font-size: 15px; }
.q-type {
  font-size: 12px; color: var(--blue-dark);
  background: rgba(10,132,255,0.1);
  padding: 3px 10px; border-radius: 980px;
}
.q-text { font-size: 16px; font-weight: 500; margin-bottom: 14px; }

/* 收藏按钮：未收藏灰星、已收藏金色 */
.fav-btn {
  margin-left: auto; background: none; border: none; cursor: pointer;
  font-size: 20px; line-height: 1; padding: 2px 6px; border-radius: 8px;
  opacity: 0.45; transition: transform .15s ease, opacity .15s ease;
}
.fav-btn:hover { transform: scale(1.15); opacity: 1; }
.fav-btn.on { opacity: 1; filter: drop-shadow(0 0 4px rgba(255, 200, 0, .6)); }

/* 计时模式：倒计时标签 */
.timer-box {
  display: inline-flex; align-items: center; gap: 6px;
  font-size: 15px; font-weight: 700; font-variant-numeric: tabular-nums;
  color: var(--blue-dark, #007aff);
  background: rgba(10, 132, 255, 0.1);
  padding: 6px 14px; border-radius: 980px;
}
.timer-box.warning { color: #e5484d; background: rgba(229, 72, 77, 0.12); animation: pulse 1s infinite; }
@keyframes pulse { 50% { opacity: 0.55; } }

/* AI 题库（管理员预览/列表） */
.question-list { display: flex; flex-direction: column; gap: 18px; }
.preview-options { display: flex; flex-direction: column; gap: 6px; }
.option-preview {
  font-size: 13.5px; padding: 7px 12px;
  background: rgba(255,255,255,0.45);
  border: 1px solid rgba(255,255,255,0.6);
  border-radius: 10px;
}
.count-input { width: 72px; text-align: center; }
.type-check { display: inline-flex; align-items: center; gap: 5px; margin-right: 14px;
  font-size: 13px; color: var(--text-2); cursor: pointer; }
.type-check input { accent-color: var(--primary); width: 15px; height: 15px; cursor: pointer; }

/* ---- AI 题库管理 ---- */
.bank-card { display: block; text-decoration: none; transition: transform .2s ease, box-shadow .2s ease; }
.bank-card:hover { transform: translateY(-3px); box-shadow: 0 10px 30px rgba(80,90,220,0.15); }
.bank-cats { display: flex; flex-wrap: wrap; gap: 6px; margin: 12px 0 14px; }
.cat-pill { font-size: 11.5px; padding: 3px 10px; border-radius: 20px;
  background: rgba(120,120,140,0.10); color: var(--muted); border: 1px solid rgba(120,120,140,0.15); }
.cat-pill.has { background: rgba(106,141,255,0.12); color: #4a6cf7;
  border-color: rgba(106,141,255,0.35); font-weight: 600; }
.bank-row { display: flex; align-items: center; gap: 12px; padding: 12px 16px;
  background: rgba(255,255,255,0.45); border: 1px solid rgba(255,255,255,0.6);
  border-radius: 12px; }
.badge-code { font-size: 11px; letter-spacing: .5px; }

/* ---- 用户端选择题库（分类 → 题库卡片） ---- */
.cat-card { padding: 18px 22px; margin-bottom: 20px; }
.user-cat-head { display: flex; align-items: center; gap: 10px; margin-bottom: 14px; }
.cat-dot { flex-shrink: 0; width: 10px; height: 10px; border-radius: 50%; }
.user-cat-head h3 { margin: 0; font-size: 17px; }
.cat-count { font-size: 12px; padding: 2px 10px; border-radius: 20px;
  background: rgba(120,120,140,.1); color: var(--muted); }
.user-banks { display: flex; flex-direction: column; gap: 10px; }
.user-bank-row { display: flex; align-items: center; gap: 14px; padding: 14px 16px;
  text-decoration: none; background: rgba(255,255,255,.55);
  border: 1px solid rgba(255,255,255,.7); border-radius: 14px;
  transition: transform .18s ease, box-shadow .18s ease, border-color .18s ease; }
.user-bank-row:hover { transform: translateY(-2px);
  box-shadow: 0 8px 24px rgba(80,90,220,.12); border-color: rgba(106,141,255,.45); }
.bank-type-chip { flex-shrink: 0; font-size: 12px; font-weight: 600;
  padding: 5px 12px; border-radius: 20px; letter-spacing: .3px;
  border: 1px solid transparent; }
.bank-info { flex: 1; min-width: 0; display: flex; flex-direction: column; gap: 3px; }
.bank-info strong { color: var(--text); font-size: 15px; }
.bank-meta { font-size: 12px; color: var(--muted); }
.bank-go { flex-shrink: 0; font-size: 13px; font-weight: 600; color: var(--primary); }
/* 题型配色：圆点实色，徽章浅底彩字 */
.cat-dot.type-single { background: #4a6cf7; }
.cat-dot.type-multi { background: #8b5cf6; }
.cat-dot.type-judge { background: #2e9e5b; }
.cat-dot.type-blank { background: #e8862e; }
.cat-dot.type-qa { background: #0ea5a4; }
.cat-dot.type-comprehensive { background: #e5484d; }
.bank-type-chip.type-single { background: rgba(74,108,247,.10); color: #4a6cf7; border-color: rgba(74,108,247,.25); }
.bank-type-chip.type-multi { background: rgba(139,92,246,.10); color: #7c3aed; border-color: rgba(139,92,246,.25); }
.bank-type-chip.type-judge { background: rgba(46,158,91,.10); color: #237a46; border-color: rgba(46,158,91,.25); }
.bank-type-chip.type-blank { background: rgba(232,134,46,.10); color: #c96a12; border-color: rgba(232,134,46,.25); }
.bank-type-chip.type-qa { background: rgba(14,165,164,.10); color: #0b7e7d; border-color: rgba(14,165,164,.25); }
.bank-type-chip.type-comprehensive { background: rgba(229,72,77,.10); color: #d0353a; border-color: rgba(229,72,77,.25); }
@media (max-width: 640px) {
  .cat-card { padding: 14px 16px; }
  .user-bank-row { flex-wrap: wrap; gap: 8px 12px; padding: 12px 14px; }
  .bank-go { width: 100%; text-align: right; }
}


.options { display: flex; flex-direction: column; gap: 10px; }
.option {
  display: flex; align-items: center; gap: 10px;
  padding: 11px 14px;
  border-radius: 12px;
  background: rgba(255,255,255,0.5);
  border: 1px solid rgba(255,255,255,0.7);
  cursor: pointer;
  transition: background .15s, border-color .15s;
  font-size: 14px;
}
.option:hover { background: rgba(255,255,255,0.8); }
.option input { accent-color: var(--blue); }
.option.correct { border-color: var(--green); background: rgba(52,199,89,0.14); }
.option.wrong   { border-color: var(--red); background: rgba(255,59,48,0.1); }

.text-answer {
  width: 100%;
  padding: 12px 16px;
  font-size: 15px; font-family: inherit;
  background: rgba(255,255,255,0.6);
  border: 1px solid rgba(255,255,255,0.8);
  border-radius: 12px; outline: none;
}
.text-answer:focus { border-color: var(--blue); box-shadow: 0 0 0 4px rgba(10,132,255,0.15); }

.action-bar { text-align: center; margin: 28px 0; }

/* ---------- 结果区 ---------- */
#result-panel { margin-top: 10px; }
.result-summary {
  padding: 22px 28px; margin-bottom: 22px;
  display: flex; align-items: center; justify-content: space-between; gap: 14px;
}
.result-score { font-size: 22px; font-weight: 700; }
.result-card { padding: 22px 28px; margin-bottom: 16px; }
.result-status { font-weight: 700; font-size: 15px; margin-bottom: 8px; }
.result-status.correct { color: #248a3d; }
.result-status.wrong { color: var(--red); }
.result-meta { color: var(--text-2); font-size: 14px; margin: 4px 0; }
.explain-box { margin-top: 14px; padding: 16px; border-radius: 14px; background: rgba(255,255,255,0.45); }
.ai-box { margin-top: 12px; padding: 18px; border-radius: 14px; background: rgba(10,132,255,0.06); border: 1px dashed rgba(10,132,255,0.4); white-space: pre-wrap; font-size: 14px; }
.ai-tag { font-size: 12px; color: var(--blue-dark); font-weight: 700; margin-bottom: 8px; display: flex; align-items: center; gap: 6px; }
.ai-loading { color: var(--text-2); font-size: 13px; }

/* ---------- 表格 ---------- */
.table-card { padding: 8px; overflow-x: auto; }
.table { width: 100%; border-collapse: collapse; font-size: 14px; }
.table th {
  text-align: left; padding: 14px 16px;
  color: var(--text-2); font-size: 12px; font-weight: 600;
  border-bottom: 1px solid rgba(0,0,0,0.06);
}
.table td { padding: 13px 16px; border-bottom: 1px solid rgba(0,0,0,0.05); vertical-align: middle; }
.table tr:last-child td { border-bottom: none; }
.table tr:hover td { background: rgba(255,255,255,0.35); }
.code-text {
  font-family: "SF Mono", Menlo, Consolas, monospace;
  background: rgba(10,132,255,0.1);
  color: var(--blue-dark);
  padding: 4px 8px; border-radius: 6px;
  font-size: 13px; font-weight: 600;
}
.actions { display: flex; gap: 8px; flex-wrap: wrap; }
.inline-form { display: inline; }
.center { text-align: center; }
.muted { color: var(--text-2); font-size: 13px; }

.form-card { padding: 28px 30px; margin-bottom: 28px; }

/* ---------- 页脚 ---------- */
.glass-footer {
  position: fixed; bottom: 0; left: 0; right: 0;
  text-align: center;
  padding: 10px;
  font-size: 12px;
  color: var(--text-2);
  background: rgba(255,255,255,0.35);
  -webkit-backdrop-filter: blur(20px);
  backdrop-filter: blur(20px);
  border-top: 1px solid rgba(255,255,255,0.5);
  z-index: 40;
}

.hidden { display: none !important; }

@media (max-width: 720px) {
  .grid-2 { grid-template-columns: 1fr; }
  .span-2 { grid-column: auto; }
  .nav-inner { padding: 10px 16px; }
  .nav-links { gap: 10px; }
  .hero { padding: 24px; }
  .subject-grid { grid-template-columns: 1fr 1fr; }
}

/* ===== 练习页答题卡 ===== */
.practice-layout { display: flex; gap: 20px; align-items: flex-start; }
.answer-sheet { position: sticky; top: 90px; width: 190px; flex: 0 0 190px; padding: 18px; }
.sheet-grid { display: grid; grid-template-columns: repeat(4, 1fr); gap: 8px; }
.sheet-num {
  width: 100%; height: 38px; border-radius: 10px; border: 1px solid var(--border, rgba(255,255,255,.5));
  background: rgba(255,255,255,.45); color: var(--text, #333); font-size: 14px; font-weight: 600;
  cursor: pointer; transition: all .15s;
}
.sheet-num:hover { background: rgba(255,255,255,.8); }
.sheet-num.answered { background: #34c759; color: #fff; border-color: #34c759; }
.sheet-num.current { outline: 2px solid var(--primary, #007aff); outline-offset: 1px; }
.sheet-legend { display: flex; gap: 12px; margin-top: 14px; font-size: 12px; color: var(--muted, #888); }
.sheet-legend span { display: inline-flex; align-items: center; gap: 4px; }
.dot { width: 10px; height: 10px; border-radius: 50%; background: rgba(0,0,0,.15); display: inline-block; }
.dot-answered { background: #34c759; }
.dot-current { background: var(--primary, #007aff); }
.practice-main { flex: 1; min-width: 0; }
.nav-bar { display: flex; align-items: center; gap: 12px; margin-top: 18px; padding: 14px 18px;
  background: rgba(255,255,255,.55); border-radius: 16px; border: 1px solid rgba(255,255,255,.7);
  backdrop-filter: blur(20px); -webkit-backdrop-filter: blur(20px);
  position: sticky; bottom: 12px; }
.nav-bar .btn:disabled { opacity: .4; cursor: not-allowed; }

/* 手机端答题卡：按钮并入底部操作栏（不遮挡题目），点击弹出抽屉 */
.sheet-fab { display: none; align-items: center; justify-content: center; gap: 6px;
  height: 44px; padding: 0 16px; border: none; border-radius: 22px;
  background: var(--primary, #007aff); color: #fff; font-size: 14px; font-weight: 600;
  box-shadow: 0 4px 14px rgba(0, 122, 255, .35); cursor: pointer;
  touch-action: manipulation; user-select: none; -webkit-user-select: none; }
.sheet-drawer-mask { display: none; position: fixed; inset: 0; z-index: 70;
  background: rgba(0, 0, 0, .35); }
.sheet-drawer { display: none; position: fixed; left: 0; right: 0; bottom: 0; z-index: 80;
  background: #fff; border-radius: 20px 20px 0 0; padding: 18px 18px calc(22px + env(safe-area-inset-bottom));
  box-shadow: 0 -8px 30px rgba(0, 0, 0, .15); max-height: 72vh; overflow-y: auto; }
.sheet-drawer.open, .sheet-drawer-mask.open { display: block; }
.sheet-drawer-head { display: flex; justify-content: space-between; align-items: center; margin-bottom: 14px; }
.sheet-drawer .sheet-grid { grid-template-columns: repeat(6, 1fr); }

@media (max-width: 768px) {
  .practice-layout { flex-direction: column; }
  .answer-sheet { display: none; }
  .sheet-fab { display: flex; }
  .nav-bar { flex-wrap: wrap; gap: 8px; padding: 10px 12px; }
  .nav-bar #nav-progress { flex: 1; min-width: 0; font-size: 12px; white-space: nowrap; }
  .nav-bar #btn-submit { flex: 1; }
}

/* ===== 移动端适配增强 ===== */
@media (max-width: 720px) {
  .container { padding: 20px 14px 90px; }
  .hero { padding: 20px 18px; margin-bottom: 20px; }
  .hero h1 { font-size: 22px; }
  .section-head { flex-direction: column; align-items: flex-start; gap: 10px; }
  .section-head h1, .section-head h2 { font-size: 20px; }
  .head-actions { flex-wrap: wrap; }
  .practice-head { flex-direction: column; align-items: flex-start; gap: 12px; }
  .toolbar { padding: 14px 16px; }
  .toolbar-form { gap: 12px; }
  .subject-grid { grid-template-columns: 1fr 1fr; gap: 14px; }
  .subject-card { padding: 18px 16px; }
  .subject-name { font-size: 17px; }
  .bank-row { flex-wrap: wrap; }
  .flash-stack { left: 14px; right: 14px; top: 70px; }
  .flash { max-width: none; font-size: 13px; }
  .result-summary { flex-direction: column; align-items: flex-start; gap: 10px; padding: 18px; }
  .result-card { padding: 18px; }
  .question-card { padding: 18px 16px; }
  .q-text { font-size: 15px; }
  .option { padding: 12px 12px; font-size: 14px; }
  .modal-card { padding: 26px 20px; }
  .form-card { padding: 22px 18px; }
  .grid-2 { grid-template-columns: 1fr; }
  .span-2 { grid-column: auto; }
  .table { font-size: 12.5px; }
  .table th, .table td { padding: 10px 12px; }
  .btn-lg { padding: 12px 26px; }
}

@media (max-width: 480px) {
  .nav-inner { flex-wrap: wrap; gap: 8px; padding: 10px 14px; }
  .brand { font-size: 15px; }
  .nav-links {
    width: 100%;
    display: flex; flex-wrap: nowrap; gap: 12px;
    overflow-x: auto; -webkit-overflow-scrolling: touch;
    padding-bottom: 4px; font-size: 13px;
  }
  .nav-user { display: none; }
  .subject-grid { grid-template-columns: 1fr; }
  .sheet-grid { grid-template-columns: repeat(6, 1fr); }
  .nav-bar { flex-wrap: wrap; }
  .nav-bar .btn { flex: 1; min-width: 90px; }
  .hero h1 { font-size: 20px; }
  .auth-card { padding: 30px 22px; }
  .content-text { font-size: 13px; line-height: 1.9; }
  .content-panel { max-height: 60vh; }
}

/* 站内通知 */
.nav-notif { position: relative; }
.nav-badge {
  display: inline-flex; align-items: center; justify-content: center;
  min-width: 18px; height: 18px; padding: 0 5px; margin-left: 4px;
  border-radius: 9px; background: #e74c3c; color: #fff;
  font-size: 11px; line-height: 1; vertical-align: middle;
}
.notif-list { display: flex; flex-direction: column; gap: 12px; }
.notif-item { padding: 16px 20px; }
.notif-item.unread { border-left: 3px solid #4f81bd; }
.notif-head { display: flex; align-items: center; gap: 10px; flex-wrap: wrap; }
.notif-type { font-size: 12px; padding: 2px 8px; border-radius: 10px; background: #eef2f8; color: #4f81bd; white-space: nowrap; }
.notif-type.type-expire { background: #fdf3e7; color: #e67e22; }
.notif-type.type-newbank { background: #e9f7ef; color: #27ae60; }
.notif-title { margin: 0; font-size: 15px; }
.notif-dot { display: inline-block; width: 8px; height: 8px; margin-left: 6px; border-radius: 50%; background: #e74c3c; }
.notif-time { margin-left: auto; color: #999; font-size: 12px; white-space: nowrap; }
.notif-content { margin: 8px 0 4px; color: #666; }

/* ===== 落地介绍封面 ===== */
.landing { padding: 8px 0 40px; }

.land-hero {
  display: grid;
  grid-template-columns: 1.15fr 0.85fr;
  gap: 30px;
  align-items: center;
  padding: 56px 52px;
  margin-bottom: 44px;
  background: linear-gradient(135deg, rgba(255,255,255,0.62), rgba(255,255,255,0.35));
  overflow: hidden;
}
.land-tag {
  display: inline-flex; align-items: center; gap: 6px;
  font-size: 13px; font-weight: 600; color: var(--blue-dark);
  background: rgba(10,132,255,0.1);
  border: 1px solid rgba(10,132,255,0.25);
  padding: 6px 14px; border-radius: 980px; margin-bottom: 18px;
}
.land-hero h1 {
  font-size: 44px; font-weight: 800; letter-spacing: -1px; line-height: 1.16;
  background: linear-gradient(120deg, #0a60e0, #7d5fff 55%, #c05fff);
  -webkit-background-clip: text; background-clip: text;
  -webkit-text-fill-color: transparent; color: transparent;
  margin-bottom: 16px;
}
.land-hero p { color: var(--text-2); font-size: 16px; max-width: 470px; margin-bottom: 28px; }
.land-cta { display: flex; gap: 14px; flex-wrap: wrap; margin-bottom: 30px; }
.land-stats { display: flex; gap: 36px; }
.land-stat b { font-size: 26px; font-weight: 800; display: block; letter-spacing: -0.5px; }
.land-stat span { color: var(--text-2); font-size: 13px; }

/* Hero 右侧视觉 */
.land-art { position: relative; height: 300px; }
.land-art-core {
  width: 196px; height: 196px; margin: 0 auto;
  display: grid; place-items: center; font-size: 86px;
  border-radius: 48px;
  background: linear-gradient(135deg, #0a84ff, #7d5fff);
  box-shadow: 0 26px 60px rgba(10, 132, 255, 0.4);
  animation: floatY 5s ease-in-out infinite;
}
@keyframes floatY {
  0%, 100% { transform: translateY(0); }
  50%      { transform: translateY(-14px); }
}
.land-float {
  position: absolute;
  display: flex; align-items: center; gap: 8px;
  background: rgba(255,255,255,0.88);
  border: 1px solid rgba(255,255,255,0.95);
  box-shadow: 0 12px 30px rgba(31, 38, 135, 0.15);
  border-radius: 16px;
  padding: 10px 16px;
  font-size: 14px; font-weight: 600;
  animation: floatY 6s ease-in-out infinite;
}
.land-float.f1 { top: 14px; right: 6%;  animation-delay: -2s; }
.land-float.f2 { bottom: 34px; left: 4%; animation-delay: -4s; }
.land-float.f3 { bottom: -4px; right: 12%; animation-delay: -1s; }

/* 学科徽章 */
.land-subjects { display: flex; flex-wrap: wrap; gap: 12px; margin-bottom: 46px; }
.land-subject {
  padding: 10px 20px; border-radius: 980px;
  background: rgba(255,255,255,0.55);
  border: 1px solid rgba(255,255,255,0.8);
  font-size: 14px; font-weight: 600; color: var(--text);
  box-shadow: 0 4px 14px rgba(31, 38, 135, 0.08);
  transition: transform .18s ease, box-shadow .18s ease;
}
.land-subject:hover { transform: translateY(-3px); box-shadow: 0 8px 22px rgba(10, 132, 255, 0.18); }

/* 功能亮点 */
.land-features { display: grid; grid-template-columns: repeat(4, 1fr); gap: 20px; margin-bottom: 46px; }
.land-feature { padding: 26px 24px; transition: transform .2s ease, box-shadow .2s ease; }
.land-feature:hover { transform: translateY(-5px); box-shadow: 0 16px 44px rgba(31, 38, 135, 0.16); }
.land-feature-ico {
  width: 52px; height: 52px; display: grid; place-items: center;
  font-size: 26px; border-radius: 16px; margin-bottom: 16px;
  background: linear-gradient(135deg, rgba(10,132,255,0.12), rgba(125,95,255,0.12));
}
.land-feature h3 { font-size: 17px; margin-bottom: 8px; }
.land-feature p { color: var(--text-2); font-size: 13.5px; }

/* 底部 CTA */
.land-final {
  text-align: center; padding: 52px 32px;
  background: linear-gradient(135deg, rgba(10,132,255,0.1), rgba(125,95,255,0.08));
}
.land-final h2 { font-size: 28px; margin-bottom: 10px; }
.land-final p { color: var(--text-2); margin-bottom: 26px; }
.land-final .land-cta { justify-content: center; margin-bottom: 0; }

@media (max-width: 860px) {
  .land-hero { grid-template-columns: 1fr; padding: 34px 26px; }
  .land-hero h1 { font-size: 32px; }
  .land-art { height: 240px; margin-top: 12px; }
  .land-features { grid-template-columns: repeat(2, 1fr); }
}
@media (max-width: 520px) {
  .land-hero h1 { font-size: 27px; }
  .land-hero p { font-size: 15px; }
  .land-stats { gap: 22px; }
  .land-features { grid-template-columns: 1fr; }
  .land-final { padding: 36px 20px; }
  .land-final h2 { font-size: 22px; }
}