:root {
  --primary: #4f46e5;
  --primary-dark: #4338ca;
  --primary-soft: #eef2ff;
  --ok: #16a34a;
  --ok-soft: #dcfce7;
  --bad: #dc2626;
  --bad-soft: #fee2e2;
  --warn: #d97706;
  --warn-soft: #fef3c7;
  --text: #1e293b;
  --text-2: #64748b;
  --text-3: #94a3b8;
  --line: #e2e8f0;
  --bg: #f5f7fb;
  --card: #ffffff;
  --radius: 12px;
  --shadow: 0 1px 3px rgba(15, 23, 42, .06), 0 8px 24px rgba(15, 23, 42, .05);
}

* { box-sizing: border-box; }

html, body {
  margin: 0;
  padding: 0;
  height: 100%;
  background: var(--bg);
  color: var(--text);
  font-family: "Microsoft YaHei", "PingFang SC", "Helvetica Neue", Arial, sans-serif;
  font-size: 14px;
  line-height: 1.6;
}

button, input, select, textarea { font-family: inherit; font-size: 14px; }
a { color: var(--primary); text-decoration: none; }
::-webkit-scrollbar { width: 9px; height: 9px; }
::-webkit-scrollbar-thumb { background: #cbd5e1; border-radius: 8px; }
::-webkit-scrollbar-thumb:hover { background: #94a3b8; }

#app { display: flex; min-height: 100vh; }

/* ---------------- 侧边栏 ---------------- */
.sidebar {
  width: 216px; flex: 0 0 216px; background: #fff; border-right: 1px solid var(--line);
  display: flex; flex-direction: column; position: sticky; top: 0; height: 100vh;
}
.logo {
  padding: 20px 18px 16px; border-bottom: 1px solid var(--line);
}
.logo h1 { font-size: 16px; margin: 0 0 2px; letter-spacing: .5px; }
.logo p { margin: 0; font-size: 11.5px; color: var(--text-3); }
.nav { padding: 10px 8px; flex: 1; overflow-y: auto; }
.nav-item {
  display: flex; align-items: center; gap: 10px; padding: 9px 12px; margin-bottom: 2px;
  border-radius: 9px; cursor: pointer; color: var(--text-2); font-size: 13.5px;
  border: none; background: none; width: 100%; text-align: left;
}
.nav-item:hover { background: #f1f5f9; color: var(--text); }
.nav-item.active { background: var(--primary-soft); color: var(--primary-dark); font-weight: 600; }
.nav-item .ico { width: 18px; text-align: center; font-size: 15px; }
.nav-item .badge {
  margin-left: auto; background: var(--bad); color: #fff; border-radius: 10px;
  font-size: 11px; padding: 0 6px; line-height: 17px; min-width: 18px; text-align: center;
}
.sidebar-foot { padding: 10px 14px; border-top: 1px solid var(--line); font-size: 11.5px; color: var(--text-3); }

/* ---------------- 主区域 ---------------- */
.main { flex: 1; min-width: 0; display: flex; flex-direction: column; }
.topbar {
  height: 58px; background: #fff; border-bottom: 1px solid var(--line);
  display: flex; align-items: center; gap: 12px; padding: 0 22px; position: sticky; top: 0; z-index: 20;
}
.topbar h2 { font-size: 15px; margin: 0; flex: 0 0 auto; }
.topbar .spacer { flex: 1; }
.topbar select { min-width: 200px; }
.view { padding: 22px; max-width: 1180px; width: 100%; }
.hidden { display: none !important; }

/* ---------------- 通用组件 ---------------- */
.card {
  background: var(--card); border: 1px solid var(--line); border-radius: var(--radius);
  box-shadow: var(--shadow); padding: 18px; margin-bottom: 16px;
}
.card h3 { margin: 0 0 4px; font-size: 15px; }
.card .sub { color: var(--text-2); font-size: 12.5px; margin-bottom: 14px; }
.row { display: flex; gap: 12px; flex-wrap: wrap; align-items: center; }
.grid { display: grid; gap: 14px; }
.grid.c2 { grid-template-columns: repeat(auto-fit, minmax(300px, 1fr)); }
.grid.c3 { grid-template-columns: repeat(auto-fit, minmax(220px, 1fr)); }
.grid.c4 { grid-template-columns: repeat(auto-fit, minmax(165px, 1fr)); }
.spacer { flex: 1; }
.muted { color: var(--text-2); }
.tiny { font-size: 12px; }
.center { text-align: center; }
.mt0 { margin-top: 0; } .mb0 { margin-bottom: 0; } .mt8 { margin-top: 8px; } .mt16 { margin-top: 16px; }

button, .btn {
  border: 1px solid var(--line); background: #fff; color: var(--text); border-radius: 9px;
  padding: 7px 14px; cursor: pointer; transition: .15s; white-space: nowrap; line-height: 1.5;
}
button:hover, .btn:hover { border-color: #cbd5e1; background: #f8fafc; }
button:disabled { opacity: .5; cursor: not-allowed; }
button.primary, .btn.primary { background: var(--primary); border-color: var(--primary); color: #fff; }
button.primary:hover { background: var(--primary-dark); border-color: var(--primary-dark); }
button.ghost { background: transparent; border-color: transparent; color: var(--text-2); }
button.ghost:hover { background: #f1f5f9; }
button.danger { color: var(--bad); border-color: #fecaca; background: #fff5f5; }
button.danger:hover { background: var(--bad-soft); }
button.sm { padding: 4px 10px; font-size: 12.5px; border-radius: 7px; }
button.lg { padding: 11px 26px; font-size: 15px; }

input[type=text], input[type=number], input[type=password], select, textarea {
  border: 1px solid var(--line); border-radius: 9px; padding: 7px 10px; background: #fff; color: var(--text);
  outline: none; transition: .15s; max-width: 100%;
}
input:focus, select:focus, textarea:focus { border-color: var(--primary); box-shadow: 0 0 0 3px var(--primary-soft); }
textarea { width: 100%; min-height: 76px; resize: vertical; line-height: 1.7; }
label.inline { display: inline-flex; align-items: center; gap: 6px; cursor: pointer; color: var(--text-2); }
label.inline input { cursor: pointer; }

.tag {
  display: inline-block; padding: 1px 8px; border-radius: 999px; font-size: 12px;
  background: #f1f5f9; color: var(--text-2); border: 1px solid var(--line);
}
.tag.blue { background: var(--primary-soft); color: var(--primary-dark); border-color: #e0e7ff; }
.tag.green { background: var(--ok-soft); color: #15803d; border-color: #bbf7d0; }
.tag.red { background: var(--bad-soft); color: #b91c1c; border-color: #fecaca; }
.tag.amber { background: var(--warn-soft); color: #b45309; border-color: #fde68a; }

.empty { text-align: center; padding: 42px 20px; color: var(--text-3); }
.empty .big { font-size: 40px; margin-bottom: 8px; }

/* ---------------- 上传区 ---------------- */
.dropzone {
  border: 2px dashed #cbd5e1; border-radius: var(--radius); padding: 34px 20px; text-align: center;
  background: #fbfcfe; cursor: pointer; transition: .18s;
}
.dropzone:hover, .dropzone.over { border-color: var(--primary); background: var(--primary-soft); }
.dropzone .big { font-size: 34px; }
.dropzone h3 { margin: 6px 0 4px; }

/* ---------------- 题库卡片 ---------------- */
.bank-card { display: flex; flex-direction: column; gap: 8px; cursor: pointer; }
.bank-card:hover { border-color: #c7d2fe; }
.bank-card .name { font-weight: 600; font-size: 14.5px; }
.bank-card .meta { font-size: 12.5px; color: var(--text-2); }
.bank-card .chips { display: flex; flex-wrap: wrap; gap: 5px; }

/* ---------------- 组卷表 ---------------- */
table.plan { width: 100%; border-collapse: collapse; }
table.plan th, table.plan td { padding: 9px 10px; border-bottom: 1px solid var(--line); text-align: left; }
table.plan th { font-size: 12.5px; color: var(--text-2); font-weight: 500; background: #f8fafc; }
table.plan td.num { width: 150px; }
table.plan input[type=number] { width: 74px; }
.qtotal {
  display: flex; align-items: baseline; gap: 18px; padding: 14px 16px; background: var(--primary-soft);
  border-radius: var(--radius); border: 1px solid #e0e7ff;
}
.qtotal .big { font-size: 26px; font-weight: 700; color: var(--primary-dark); }
.chipbox { display: flex; flex-wrap: wrap; gap: 6px; max-height: 130px; overflow-y: auto; padding: 2px; }
.chip {
  padding: 3px 10px; border-radius: 999px; border: 1px solid var(--line); background: #fff;
  cursor: pointer; font-size: 12.5px; color: var(--text-2);
}
.chip.on { background: var(--primary); border-color: var(--primary); color: #fff; }

/* ---------------- 答题 ---------------- */
.exam-wrap { display: flex; gap: 18px; align-items: flex-start; }
.exam-main { flex: 1; min-width: 0; }
.exam-side { width: 208px; flex: 0 0 208px; position: sticky; top: 78px; }
.qcard { background: #fff; border: 1px solid var(--line); border-radius: var(--radius); box-shadow: var(--shadow); padding: 22px; }
.qhead { display: flex; align-items: center; gap: 10px; margin-bottom: 14px; }
.qno { font-size: 12.5px; color: var(--text-2); }
.stem { font-size: 15.5px; line-height: 1.85; margin-bottom: 16px; white-space: pre-wrap; }
.opts { display: flex; flex-direction: column; gap: 9px; }
.opt {
  display: flex; gap: 10px; align-items: flex-start; padding: 11px 14px; border: 1px solid var(--line);
  border-radius: 10px; cursor: pointer; transition: .15s; background: #fff;
}
.opt:hover { border-color: #c7d2fe; background: #fafbff; }
.opt.sel { border-color: var(--primary); background: var(--primary-soft); }
.opt .letter {
  width: 22px; height: 22px; flex: 0 0 22px; border-radius: 50%; background: #f1f5f9; color: var(--text-2);
  display: flex; align-items: center; justify-content: center; font-size: 12.5px; font-weight: 600;
}
.opt.sel .letter { background: var(--primary); color: #fff; }
.opt.right { border-color: var(--ok); background: var(--ok-soft); }
.opt.wrong { border-color: var(--bad); background: var(--bad-soft); }
.judge-row { display: flex; gap: 14px; }
.judge-btn {
  flex: 1; padding: 22px; font-size: 17px; border-radius: 12px; border: 2px solid var(--line);
  background: #fff; cursor: pointer;
}
.judge-btn.sel { border-color: var(--primary); background: var(--primary-soft); color: var(--primary-dark); font-weight: 600; }
.cardgrid { display: grid; grid-template-columns: repeat(5, 1fr); gap: 7px; }
.cardgrid button { padding: 6px 0; font-size: 13px; }
.cardgrid button.done { background: var(--primary-soft); border-color: #c7d2fe; color: var(--primary-dark); font-weight: 600; }
.cardgrid button.cur { background: var(--primary); border-color: var(--primary); color: #fff; font-weight: 600; }
.timer { font-size: 15px; font-weight: 600; font-variant-numeric: tabular-nums; }
.timer.warn { color: var(--bad); }

/* ---------------- 结果 ---------------- */
.score-hero { display: flex; align-items: center; gap: 26px; flex-wrap: wrap; }
.ring {
  width: 132px; height: 132px; border-radius: 50%; flex: 0 0 132px; display: flex;
  align-items: center; justify-content: center; flex-direction: column;
  background: conic-gradient(var(--primary) var(--pct, 0%), #e9edf5 0);
  position: relative;
}
.ring::after { content: ''; position: absolute; inset: 11px; background: #fff; border-radius: 50%; }
.ring .v { position: relative; z-index: 1; font-size: 30px; font-weight: 700; line-height: 1; }
.ring .t { position: relative; z-index: 1; font-size: 12px; color: var(--text-2); margin-top: 3px; }
.bar { height: 8px; background: #eef2f7; border-radius: 6px; overflow: hidden; }
.bar > i { display: block; height: 100%; background: var(--primary); border-radius: 6px; }
.bar.ok > i { background: var(--ok); }
.bar.bad > i { background: var(--bad); }
.bar.warn > i { background: var(--warn); }
.res-item { border-bottom: 1px solid var(--line); padding: 14px 0; }
.res-item:last-child { border-bottom: none; }
.res-head { display: flex; align-items: center; gap: 9px; flex-wrap: wrap; }
.res-stem { margin: 6px 0 8px; line-height: 1.8; white-space: pre-wrap; }
.mark-ok { color: var(--ok); font-weight: 700; }
.mark-bad { color: var(--bad); font-weight: 700; }
.ans-line { font-size: 13.5px; margin: 3px 0; }
.explain {
  background: #f8fafc; border-left: 3px solid #cbd5e1; padding: 10px 13px; margin-top: 9px;
  font-size: 13px; color: #475569; white-space: pre-wrap; border-radius: 0 8px 8px 0; line-height: 1.85;
}
.acc-head { display: flex; align-items: center; gap: 10px; cursor: pointer; padding: 12px 0; }
.acc-body { padding: 4px 0 14px; }
.kv { display: flex; gap: 8px; margin: 5px 0; font-size: 13.5px; }
.kv .k { color: var(--text-2); flex: 0 0 76px; }

/* ---------------- 错题 ---------------- */
.wrong-item { border: 1px solid var(--line); border-radius: 10px; padding: 14px; margin-bottom: 11px; background: #fff; }
.wrong-item .top { display: flex; align-items: center; gap: 8px; flex-wrap: wrap; margin-bottom: 6px; }

/* ---------------- 难报告 ---------------- */
.weak-card { border: 1px solid #fde68a; background: #fffdf5; border-radius: var(--radius); padding: 16px; margin-bottom: 13px; }
.weak-card h4 { margin: 0 0 8px; font-size: 14.5px; }
.weak-sec { margin: 9px 0; }
.weak-sec .h { font-size: 12.5px; color: var(--warn); font-weight: 600; margin-bottom: 3px; }
.weak-sec ul { margin: 3px 0; padding-left: 20px; }
.weak-sec li { margin: 2px 0; font-size: 13.5px; }

/* ---------------- 弹层 ---------------- */
.mask {
  position: fixed; inset: 0; background: rgba(15, 23, 42, .45); z-index: 150;
  display: flex; align-items: center; justify-content: center; padding: 24px;
}
.modal {
  background: #fff; border-radius: 14px; max-width: 860px; width: 100%; max-height: 88vh;
  display: flex; flex-direction: column; box-shadow: 0 20px 50px rgba(15, 23, 42, .3);
}
.modal-head { padding: 16px 20px; border-bottom: 1px solid var(--line); display: flex; align-items: center; gap: 10px; }
.modal-head h3 { margin: 0; font-size: 15.5px; }
.modal-body { padding: 18px 20px; overflow-y: auto; }
.modal-foot { padding: 14px 20px; border-top: 1px solid var(--line); display: flex; gap: 10px; justify-content: flex-end; }

#toast { position: fixed; top: 18px; left: 50%; transform: translateX(-50%); z-index: 200; display: flex; flex-direction: column; gap: 8px; align-items: center; }
.toast {
  background: #1e293b; color: #fff; padding: 9px 18px; border-radius: 9px; font-size: 13.5px;
  box-shadow: 0 8px 24px rgba(15,23,42,.25); animation: pop .2s ease;
}
.toast.ok { background: #15803d; } .toast.bad { background: #b91c1c; } .toast.warn { background: #b45309; }
@keyframes pop { from { opacity: 0; transform: translateY(-8px); } }

#loading {
  position: fixed; inset: 0; background: rgba(255,255,255,.72); z-index: 300;
  display: flex; align-items: center; justify-content: center; flex-direction: column; gap: 14px;
}
.spinner {
  width: 36px; height: 36px; border: 3px solid #e0e7ff; border-top-color: var(--primary);
  border-radius: 50%; animation: spin .8s linear infinite;
}
@keyframes spin { to { transform: rotate(360deg); } }

.pager { display: flex; gap: 6px; align-items: center; justify-content: center; margin-top: 12px; }
.pager button { padding: 3px 10px; }

@media print {
  .sidebar, .topbar, .no-print, #toast, .tabbar { display: none !important; }
  .view { padding: 0; }
  body { background: #fff; }
  .card { box-shadow: none; border: none; }
}

/* ==================== 登录 / 注册 ==================== */
.login-screen {
  position: fixed; inset: 0; z-index: 400; display: flex; align-items: center; justify-content: center;
  background: linear-gradient(135deg, #eef2ff 0%, #f8fafc 45%, #ecfeff 100%); padding: 20px;
}
.login-card {
  width: 380px; max-width: 100%; background: #fff; border-radius: 18px; padding: 26px 24px 22px;
  box-shadow: 0 18px 50px rgba(15, 23, 42, .13); border: 1px solid var(--line);
}
.login-brand { text-align: center; margin-bottom: 16px; }
.login-brand .logo-mark {
  width: 52px; height: 52px; margin: 0 auto 10px; border-radius: 15px; background: var(--primary);
  color: #fff; font-size: 24px; font-weight: 700; display: flex; align-items: center; justify-content: center;
}
.login-brand h1 { font-size: 18px; margin: 0 0 4px; }
.login-brand p { margin: 0; font-size: 12.5px; color: var(--text-2); }
.login-tabs { display: flex; background: #f1f5f9; border-radius: 10px; padding: 3px; margin-bottom: 16px; }
.login-tab {
  flex: 1; border: none; background: none; padding: 8px 0; border-radius: 8px; color: var(--text-2);
  font-size: 14px; cursor: pointer;
}
.login-tab.active { background: #fff; color: var(--primary-dark); font-weight: 600; box-shadow: 0 1px 3px rgba(15,23,42,.08); }
#login-form label, #reg-form label { display: block; font-size: 12.5px; color: var(--text-2); margin-bottom: 10px; }
#login-form input, #reg-form input { width: 100%; margin-top: 4px; padding: 11px 12px; font-size: 15px; }
button.block { width: 100%; }

/* ==================== 通用新增组件 ==================== */
.only-mobile { display: none !important; }
.table-wrap { width: 100%; overflow-x: auto; -webkit-overflow-scrolling: touch; }
.user-chip {
  display: flex; align-items: center; gap: 6px; border: 1px solid var(--line); background: #fff;
  border-radius: 999px; padding: 5px 12px; cursor: pointer; font-size: 13px; max-width: 230px;
}
.user-chip:hover { border-color: #c7d2fe; background: #fafbff; }
.user-chip #user-name { max-width: 110px; overflow: hidden; text-overflow: ellipsis; white-space: nowrap; }

/* 套餐卡片 */
.plan-cards { display: grid; gap: 12px; grid-template-columns: repeat(auto-fit, minmax(170px, 1fr)); }
.plan-card {
  border: 1px solid var(--line); border-radius: 14px; padding: 16px; background: #fff; text-align: center;
  display: flex; flex-direction: column; gap: 6px;
}
.plan-card.hot { border-color: var(--primary); box-shadow: 0 8px 22px rgba(79,70,229,.12); }
.plan-card .pname { font-weight: 700; font-size: 15px; }
.plan-card .price { font-size: 26px; font-weight: 800; color: var(--primary-dark); }
.plan-card .price small { font-size: 13px; font-weight: 500; color: var(--text-2); }
.plan-card .pdesc { font-size: 12.5px; color: var(--text-2); min-height: 34px; }

/* AI 分析 */
.ai-box {
  border: 1px solid #dbeafe; background: linear-gradient(180deg, #f8fbff, #fff);
  border-radius: 12px; padding: 12px 14px; margin-top: 10px;
}
.ai-box .ai-head { display: flex; align-items: center; gap: 8px; font-size: 13px; color: var(--primary-dark); font-weight: 600; margin-bottom: 6px; }
.ai-sec { margin: 8px 0; }
.ai-sec .t { font-size: 13px; font-weight: 700; color: var(--primary-dark); }
.ai-sec .b { font-size: 13.5px; color: #334155; white-space: pre-wrap; line-height: 1.85; }
.ai-loading { display: flex; align-items: center; gap: 8px; color: var(--text-2); font-size: 13px; }
.ai-loading .spinner { width: 16px; height: 16px; border-width: 2px; }

/* 会员/额度横条 */
.quota-bar { display: flex; gap: 14px; flex-wrap: wrap; font-size: 12.5px; color: var(--text-2); }
.quota-bar b { color: var(--text); }

/* 时事卡片 */
.aff-card { border: 1px solid var(--line); border-radius: 12px; padding: 13px 14px; margin-bottom: 10px; background: #fff; }
.aff-card .t { font-weight: 600; margin-bottom: 4px; }
.aff-card .m { font-size: 12.5px; color: var(--text-2); }
.aff-card .c { font-size: 13.5px; color: #475569; margin-top: 6px; line-height: 1.8; max-height: 96px; overflow: hidden; }

/* 后台表格 */
table.admin { width: 100%; border-collapse: collapse; font-size: 13px; }
table.admin th, table.admin td { padding: 8px 9px; border-bottom: 1px solid var(--line); text-align: left; white-space: nowrap; }
table.admin th { background: #f8fafc; color: var(--text-2); font-weight: 500; font-size: 12.5px; }
table.admin tr:hover td { background: #fafbff; }
.stat-grid { display: grid; gap: 12px; grid-template-columns: repeat(auto-fit, minmax(130px, 1fr)); }
.stat-card { background: #fff; border: 1px solid var(--line); border-radius: 12px; padding: 13px 15px; }
.stat-card .v { font-size: 22px; font-weight: 800; }
.stat-card .k { font-size: 12.5px; color: var(--text-2); }

.tabs { display: flex; gap: 6px; flex-wrap: wrap; margin-bottom: 14px; }
.tabs button {
  border: 1px solid var(--line); background: #fff; border-radius: 999px; padding: 6px 14px; font-size: 13px;
  cursor: pointer; color: var(--text-2);
}
.tabs button.on { background: var(--primary); border-color: var(--primary); color: #fff; font-weight: 600; }

/* ==================== 出题思路 / 记忆卡 ==================== */
.flash {
  background: #fff; border: 1px solid var(--line); border-radius: 16px; box-shadow: var(--shadow);
  padding: 22px; min-height: 260px; display: flex; flex-direction: column;
}
.flash-top { display: flex; align-items: center; gap: 8px; flex-wrap: wrap; margin-bottom: 10px; }
.flash-q { font-size: 16.5px; line-height: 1.9; white-space: pre-wrap; margin-bottom: 12px; }
.flash-opts { display: flex; flex-direction: column; gap: 6px; margin-bottom: 12px; }
.flash-opts .o { padding: 7px 12px; border: 1px solid var(--line); border-radius: 9px; background: #fbfcfe; }
.flash-opts .o.right { border-color: var(--ok); background: var(--ok-soft); font-weight: 600; }
.hintbox {
  background: #f8fafc; border-left: 3px solid var(--primary); border-radius: 0 10px 10px 0;
  padding: 10px 13px; font-size: 13.5px; line-height: 1.85; color: #334155;
}
.hintbox .h { font-weight: 700; color: var(--primary-dark); font-size: 13px; }
.mem-line { margin: 5px 0; font-size: 13.5px; }
.mem-line .k { color: var(--text-2); }
.mem-answer {
  background: linear-gradient(180deg, #f0fdf4, #fff); border: 1px solid #bbf7d0; border-radius: 12px;
  padding: 13px 15px; margin: 12px 0;
}
.mem-answer .big { font-size: 17px; font-weight: 700; color: #15803d; line-height: 1.8; }
.flash-actions { display: flex; gap: 10px; flex-wrap: wrap; align-items: center; margin-top: auto; padding-top: 14px; }
.flash-progress { height: 6px; background: #eef2f7; border-radius: 6px; overflow: hidden; margin-bottom: 12px; }
.flash-progress > i { display: block; height: 100%; background: var(--primary); }
.mem-chip { display: inline-flex; align-items: center; gap: 4px; }

@media (max-width: 860px) {
  .flash { padding: 16px; min-height: 200px; }
  .flash-q { font-size: 16px; }
  .flash-actions button { flex: 1 1 44%; }
}

/* ==================== 手机端 ==================== */
@media (max-width: 860px) {
  html, body { font-size: 15px; }
  .only-mobile { display: flex !important; }
  button.only-mobile { display: inline-flex !important; }
  .only-desktop { display: none !important; }

  #app { display: block; }
  .sidebar {
    position: fixed; left: 0; top: 0; bottom: 0; width: 254px; height: 100vh; z-index: 120;
    transform: translateX(-102%); transition: transform .22s ease; box-shadow: 0 0 40px rgba(15,23,42,.25);
  }
  .sidebar.open { transform: translateX(0); }
  .main { min-height: 100vh; padding-bottom: 68px; }
  .topbar {
    height: 54px; padding: 0 12px; gap: 8px; flex-wrap: nowrap; overflow-x: auto;
  }
  .topbar h2 { font-size: 15px; flex: 0 0 auto; }
  #bank-select { min-width: 0; flex: 1 1 auto; max-width: 42vw; padding: 6px 8px; font-size: 13px; }
  .user-chip { max-width: 130px; padding: 4px 8px; font-size: 12.5px; }
  .user-chip #user-name { max-width: 56px; }
  .view { padding: 12px 12px 26px; }
  .card { padding: 14px; border-radius: 14px; }
  .grid.c2, .grid.c3, .grid.c4 { grid-template-columns: 1fr; }
  .dropzone { padding: 24px 14px; }
  .qtotal { flex-wrap: wrap; gap: 10px; }
  .qtotal .big { font-size: 22px; }

  /* 答题：答题卡挪到题目下方，横向滚动 */
  .exam-wrap { display: block; }
  .exam-side { position: static; width: auto; margin-top: 12px; }
  .cardgrid { grid-template-columns: repeat(6, 1fr); }
  .qcard { padding: 16px; }
  .stem { font-size: 16px; }
  .opt { padding: 13px 14px; font-size: 15px; }
  .judge-btn { padding: 18px; font-size: 16px; }
  input, select, textarea, button { font-size: 15px; }
  button, .btn { padding: 9px 14px; }

  /* 全屏弹层：改成底部抽屉样式。
     注意 z-index —— 弹层必须高于底部导航条（.tabbar 是 110）和侧栏抽屉（120），
     否则「确定/取消」这一行会被导航条盖住，手机上根本点不到（曾经的 bug）。 */
  .mask { padding: 0; align-items: flex-end; }
  .modal { max-width: 100%; width: 100%; max-height: 92vh; border-radius: 16px 16px 0 0; }
  .modal-foot {
    position: sticky; bottom: 0; background: #fff;
    padding-bottom: calc(14px + env(safe-area-inset-bottom));
  }
  .modal-foot button { flex: 1 1 auto; padding: 12px 14px; }

  .login-card { width: 100%; padding: 22px 18px; }
  .stat-grid { grid-template-columns: repeat(2, 1fr); }
  .plan-cards { grid-template-columns: 1fr 1fr; }
  table.admin { font-size: 12.5px; }
}

/* 手机底部导航条 */
.tabbar {
  position: fixed; left: 0; right: 0; bottom: 0; z-index: 110; background: #fff;
  border-top: 1px solid var(--line); padding: 6px 4px calc(6px + env(safe-area-inset-bottom));
  justify-content: space-around; display: none;
}
.tabbar button {
  flex: 1; border: none; background: none; display: flex; flex-direction: column; align-items: center;
  gap: 2px; font-size: 11px; color: var(--text-2); padding: 4px 0; border-radius: 10px;
}
.tabbar button span { font-size: 18px; line-height: 1.1; }
.tabbar button.active { color: var(--primary-dark); font-weight: 600; background: var(--primary-soft); }

@media (max-width: 860px) {
  .tabbar { display: flex; }
}

/* ============ 分站：返回主站链接 ============ */
.site-back {
  display: block; margin: 8px 14px 12px; padding: 7px 10px; border-radius: 9px;
  background: var(--primary-soft); color: var(--primary-dark); font-size: 12.5px;
  font-weight: 600; text-align: center; text-decoration: none; border: 1px solid transparent;
}
.site-back:hover { border-color: var(--primary); }
#login-link a { color: var(--primary-dark); text-decoration: none; font-weight: 600; }
#login-link a:hover { text-decoration: underline; }

/* ============ 登录 / 注册：图形验证码 ============ */
.cap-row { display: flex; align-items: center; gap: 8px; margin-top: 4px; }
#login-form .cap-row input, #reg-form .cap-row input { margin-top: 0; flex: 1 1 auto; min-width: 0; letter-spacing: 2px; }
.cap-img {
  flex: 0 0 120px; width: 120px; height: 40px; border-radius: 8px; overflow: hidden;
  background: #eef2ff; cursor: pointer; display: flex; align-items: center; justify-content: center;
  border: 1px solid var(--line); font-size: 12px; color: var(--text-3); user-select: none;
}
.cap-img svg { width: 100%; height: 100%; display: block; }
.cap-img.loading { opacity: .55; }
.cap-img:hover { border-color: var(--primary); }
@media (max-width: 420px) {
  .cap-img { flex-basis: 104px; width: 104px; height: 38px; }
}