/* ===========================================================
   练习助手 · 样式表
   =========================================================== */

:root {
  --bg: #f4f6fb;
  --card: #ffffff;
  --ink: #1b2431;
  --ink-2: #435165;
  --muted: #7b8798;
  --line: #e6ebf3;
  --line-2: #eef2f8;
  --primary: #3d6bf5;
  --primary-d: #2f57cf;
  --primary-soft: #ecf1ff;
  --ok: #16a06a;
  --ok-soft: #e9f8f1;
  --ok-line: #b7e6cf;
  --bad: #e04b45;
  --bad-soft: #fdeceb;
  --bad-line: #f6c3c0;
  --warn: #d98b0b;
  --warn-soft: #fdf5e3;
  --radius: 14px;
  --shadow: 0 1px 2px rgba(21, 35, 60, .04), 0 10px 26px rgba(21, 35, 60, .055);
}

* { box-sizing: border-box; }

html, body { margin: 0; padding: 0; }

body {
  background: var(--bg);
  color: var(--ink);
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", "PingFang SC",
    "Hiragino Sans GB", "Microsoft YaHei", "Source Han Sans SC", sans-serif;
  font-size: 15px;
  line-height: 1.65;
  -webkit-font-smoothing: antialiased;
}

h1, h2, h3, h4 { margin: 0; font-weight: 650; letter-spacing: .2px; }
p { margin: 0; }
button { font-family: inherit; font-size: inherit; }
code {
  font-family: ui-monospace, SFMono-Regular, Menlo, Consolas, "Courier New", monospace;
  font-size: .9em;
  background: #f1f4fa;
  border: 1px solid var(--line);
  border-radius: 5px;
  padding: 1px 5px;
  color: #33457a;
}

.is-hidden { display: none !important; }

/* ---------------- 顶栏 ---------------- */

.topbar {
  position: sticky;
  top: 0;
  z-index: 20;
  background: #ffffff;
  border-bottom: 1px solid var(--line);
}

.topbar-inner {
  max-width: 1120px;
  margin: 0 auto;
  padding: 13px 20px;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 16px;
}

/* 顶栏品牌区可点击（返回首页） */
.brand {
  display: flex;
  align-items: center;
  gap: 11px;
  padding: 2px 4px;
  margin: -2px -4px;
  border: 0;
  border-radius: 10px;
  background: none;
  font: inherit;
  color: inherit;
  text-align: left;
  cursor: pointer;
  transition: background .15s ease;
}

/* 触屏设备上避免 hover 态粘住 */
@media (hover: hover) {
  .brand:hover { background: #f4f7ff; }
}

.brand:focus-visible { outline: 2px solid var(--primary); outline-offset: 2px; }
.brand:active .brand-mark { transform: scale(.96); }

.brand-mark {
  width: 36px; height: 36px;
  border-radius: 10px;
  overflow: hidden;
  display: flex;
  box-shadow: 0 4px 12px rgba(61, 107, 245, .3);
  transition: transform .15s ease;
}

.brand-mark img { width: 100%; height: 100%; display: block; }

.brand-text { display: flex; flex-direction: column; line-height: 1.25; }
.brand-text strong { font-size: 16px; }
.brand-text span { font-size: 12px; color: var(--muted); }

.steps { display: flex; align-items: center; gap: 6px; margin: 0; padding: 0; list-style: none; }

.step {
  display: flex; align-items: center; gap: 6px;
  font-size: 13px;
  color: var(--muted);
  padding: 5px 11px;
  border-radius: 99px;
  background: transparent;
  transition: all .18s ease;
}

.step i {
  width: 17px; height: 17px;
  border-radius: 50%;
  background: #e8edf6;
  color: #8390a3;
  font-style: normal;
  font-size: 11px;
  display: flex; align-items: center; justify-content: center;
}

.step.is-active { color: var(--primary-d); background: var(--primary-soft); font-weight: 600; }
.step.is-active i { background: var(--primary); color: #fff; }
.step.is-done { color: var(--ok); }
.step.is-done i { background: var(--ok-soft); color: var(--ok); }

/* ---------------- 布局 ---------------- */

.container { max-width: 1120px; margin: 0 auto; padding: 26px 20px 72px; }

.card {
  background: var(--card);
  border: 1px solid var(--line);
  border-radius: var(--radius);
  box-shadow: var(--shadow);
  padding: 20px;
}

.card-title { font-size: 15px; margin-bottom: 14px; }

.hero { margin-bottom: 20px; }
.hero h1 { font-size: 24px; margin-bottom: 6px; }
.hero p { color: var(--ink-2); max-width: 880px; font-size: 14px; }

.upload-grid {
  display: grid;
  grid-template-columns: minmax(0, 1.62fr) minmax(280px, .85fr);
  gap: 16px;
  align-items: start;
}

/* 左侧题库卡撑满整行高度，避免右侧设置面板较高时左边留下大片空白 */
.upload-grid > .card:not(.settings) {
  align-self: stretch;
  display: flex;
  flex-direction: column;
}

.practice-body {
  display: grid;
  grid-template-columns: minmax(0, 1.62fr) minmax(250px, .85fr);
  gap: 16px;
  align-items: start;
}

/* ---------------- 按钮 ---------------- */

.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 6px;
  border: 1px solid transparent;
  border-radius: 10px;
  padding: 9px 16px;
  font-size: 14px;
  font-weight: 550;
  cursor: pointer;
  transition: all .16s ease;
  white-space: nowrap;
}

.btn-primary { background: var(--primary); color: #fff; box-shadow: 0 4px 12px rgba(61, 107, 245, .22); }
.btn-primary:hover:not(:disabled) { background: var(--primary-d); transform: translateY(-1px); }
.btn-primary:disabled { background: #c3cee8; box-shadow: none; cursor: not-allowed; }

.btn-ghost { background: #fff; border-color: var(--line); color: var(--ink-2); }
.btn-ghost:hover:not(:disabled) { border-color: #c9d6f2; color: var(--primary-d); background: #f8faff; }
.btn-ghost:disabled { opacity: .45; cursor: not-allowed; }

.btn-block { width: 100%; }
.btn-sm { padding: 6px 12px; font-size: 13px; }

.btn-online {
  background: var(--primary-soft);
  border-color: #c3d3fb;
  color: var(--primary-d);
}
.btn-online:hover:not(:disabled) { background: #e2eaff; border-color: var(--primary); }
.btn-online:disabled { opacity: .6; cursor: progress; }

.btn-danger { background: var(--bad); color: #fff; box-shadow: 0 4px 12px rgba(224, 75, 69, .2); }
.btn-danger:hover:not(:disabled) { background: #c93c37; transform: translateY(-1px); }

/* ---------------- 站点内确认弹窗 ---------------- */

body.modal-open { overflow: hidden; }

.modal {
  position: fixed;
  inset: 0;
  z-index: 60;
  display: flex;
  align-items: center;
  justify-content: center;
  padding: 22px;
}

.modal-mask {
  position: absolute;
  inset: 0;
  background: rgba(17, 26, 43, .46);
}

.modal-card {
  position: relative;
  width: min(430px, 100%);
  max-height: calc(100vh - 44px);
  overflow-y: auto;
  background: var(--card);
  border-radius: 16px;
  padding: 22px 22px 18px;
  box-shadow: 0 24px 60px rgba(15, 25, 45, .28);
  animation: modal-in .16s ease-out;
}

@keyframes modal-in {
  from { opacity: 0; transform: translateY(10px) scale(.985); }
  to { opacity: 1; transform: none; }
}

.modal-title { font-size: 16px; font-weight: 650; margin-bottom: 9px; }

.modal-text {
  font-size: 13.5px;
  line-height: 1.75;
  color: var(--ink-2);
  white-space: pre-line;
}

.modal-actions {
  display: flex;
  justify-content: flex-end;
  gap: 10px;
  margin-top: 20px;
}

.modal-actions .btn { min-width: 88px; }

/* 在线题库选择面板 */

.modal-card.is-wide { width: min(560px, 100%); }

.online-head { display: flex; align-items: baseline; justify-content: space-between; gap: 12px; }
.online-count { font-size: 12.5px; color: var(--muted); flex: none; }

.online-list {
  display: flex;
  flex-direction: column;
  gap: 8px;
  margin-top: 14px;
  max-height: min(48vh, 360px);
  overflow-y: auto;
}

.online-item {
  display: flex;
  align-items: center;
  gap: 12px;
  width: 100%;
  padding: 12px 14px;
  border: 1px solid var(--line);
  border-radius: 11px;
  background: #fff;
  text-align: left;
  cursor: pointer;
  transition: all .14s ease;
}

.online-item:hover:not(:disabled) { border-color: var(--primary); background: var(--primary-soft); }
.online-item:disabled { cursor: progress; opacity: .7; }

.oi-main { display: flex; flex-direction: column; gap: 3px; flex: 1; min-width: 0; }
.oi-name { font-size: 14px; font-weight: 600; color: var(--ink); }
.oi-total { font-size: 12.5px; color: var(--ink-2); }
.oi-types { font-size: 12px; color: var(--muted); line-height: 1.5; }
.oi-go { flex: none; font-size: 12.5px; color: var(--primary-d); font-weight: 550; }

.online-empty {
  margin: 0;
  padding: 22px 8px;
  text-align: center;
  font-size: 13px;
  color: var(--muted);
  line-height: 1.7;
  white-space: pre-line;
}

.modal-text.is-error { color: #a8342f; }

/* ---------------- 上传区 ---------------- */

.dropzone {
  border: 1.5px dashed #c9d5ea;
  border-radius: 12px;
  background: linear-gradient(180deg, #fbfcff, #f7f9fe);
  padding: 30px 20px;
  text-align: center;
  cursor: pointer;
  transition: all .18s ease;
  outline: none;
  /* 跟随卡片高度伸缩，内容始终居中，卡片不会被拉成上重下空 */
  flex: 1 1 auto;
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
}

.dropzone:hover, .dropzone:focus-visible { border-color: var(--primary); background: #f4f8ff; }
.dropzone.is-drag { border-color: var(--primary); background: var(--primary-soft); border-style: solid; }

.dz-icon { width: 40px; height: 40px; color: var(--primary); margin-bottom: 8px; }
.dz-title { font-size: 15px; font-weight: 600; color: var(--ink); }
.dz-hint { font-size: 12.5px; color: var(--muted); margin-top: 3px; }

.upload-actions { display: flex; flex-wrap: wrap; gap: 8px; margin-top: 14px; }

.upload-hint {
  margin-top: 10px;
  font-size: 12.5px;
  line-height: 1.6;
  color: var(--muted);
}

.notice {
  margin-top: 14px;
  padding: 10px 13px;
  border-radius: 10px;
  font-size: 13px;
  line-height: 1.6;
  border: 1px solid var(--line);
  background: #f8fafd;
  color: var(--ink-2);
}

.notice.is-error { background: var(--bad-soft); border-color: var(--bad-line); color: #a8342f; }
.notice.is-warn { background: var(--warn-soft); border-color: #f2ddb0; color: #7d5a10; }
.notice.is-ok { background: var(--ok-soft); border-color: var(--ok-line); color: #0d7550; }
.notice ul { margin: 4px 0 0; padding-left: 18px; }
.notice li { margin: 1px 0; }

/* ---------------- 题库信息卡 ---------------- */

.bank-card {
  margin-top: 14px;
  border: 1px solid var(--line);
  border-radius: 12px;
  padding: 14px 16px;
  background: linear-gradient(180deg, #ffffff, #fafbff);
}

.bank-head { display: flex; align-items: baseline; gap: 8px; flex-wrap: wrap; }
.bank-head h3 { font-size: 15.5px; }
.bank-head .bank-count { font-size: 12.5px; color: var(--muted); }

.bank-chips { display: flex; flex-wrap: wrap; gap: 6px; margin-top: 9px; }

.chip {
  font-size: 12px;
  padding: 2px 10px;
  border-radius: 99px;
  background: #f1f5fd;
  color: #42557d;
  border: 1px solid #e3eaf8;
}

.chip b { color: var(--primary-d); font-weight: 650; }

.bank-score { margin-top: 9px; font-size: 12.5px; color: var(--muted); }

/* ---------------- 设置面板 ---------------- */

.settings { position: sticky; top: 78px; }

.field { margin-bottom: 16px; }
.field-label { font-size: 12.5px; color: var(--muted); margin-bottom: 7px; font-weight: 600; letter-spacing: .3px; }

.choice {
  display: flex;
  gap: 9px;
  padding: 10px 12px;
  border: 1px solid var(--line);
  border-radius: 11px;
  cursor: pointer;
  margin-bottom: 7px;
  transition: all .15s ease;
  background: #fff;
}

.choice:hover { border-color: #c9d6f2; background: #fbfcff; }
.choice input { accent-color: var(--primary); margin: 3px 0 0; flex: none; }

.choice-body { display: flex; flex-direction: column; line-height: 1.45; }
.choice-title { font-size: 13.5px; font-weight: 550; }
.choice-desc { font-size: 12px; color: var(--muted); margin-top: 1px; }

.choice:has(input:checked) { border-color: var(--primary); background: var(--primary-soft); }
.choice-sm { padding: 8px 12px; margin-bottom: 6px; }

/* 开关行：选项顺序随机 */
.switch-row {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 12px;
  padding-top: 13px;
  margin-bottom: 18px;
  border-top: 1px solid var(--line);
}

.switch-text { display: flex; flex-direction: column; gap: 3px; min-width: 0; }
.switch-title { font-size: 13.5px; font-weight: 550; color: var(--ink); }
.switch-desc { font-size: 12px; color: var(--muted); line-height: 1.4; }
.switch-desc.is-warn { color: var(--warn); }

.switch {
  flex: none;
  width: 48px;
  height: 28px;
  padding: 0;
  border: none;
  border-radius: 99px;
  background: #d7dfec;
  cursor: pointer;
  position: relative;
  transition: background .18s ease;
}

.switch-knob {
  position: absolute;
  top: 3px;
  left: 3px;
  width: 22px;
  height: 22px;
  border-radius: 50%;
  background: #fff;
  box-shadow: 0 1px 3px rgba(20, 32, 60, .24);
  transition: transform .18s ease;
}

.switch.is-on { background: var(--primary); }
.switch.is-on .switch-knob { transform: translateX(20px); }
.switch:focus-visible { outline: 2px solid var(--primary); outline-offset: 2px; }
.switch:hover { background: #c8d2e4; }
.switch.is-on:hover { background: var(--primary-d); }

.settings-tip { margin-top: 10px; font-size: 12px; color: var(--muted); line-height: 1.5; }

/* ---------------- 格式说明 ---------------- */

.doc { margin-top: 16px; }
.doc > summary {
  cursor: pointer;
  font-weight: 600;
  font-size: 14.5px;
  list-style: none;
  display: flex;
  align-items: center;
  gap: 8px;
  color: var(--ink-2);
}
.doc > summary::-webkit-details-marker { display: none; }
.doc > summary::before {
  content: "+";
  width: 18px; height: 18px;
  border-radius: 6px;
  background: var(--primary-soft);
  color: var(--primary-d);
  font-size: 14px;
  line-height: 18px;
  text-align: center;
  flex: none;
}
.doc[open] > summary::before { content: "−"; }

.doc-body { margin-top: 14px; border-top: 1px solid var(--line-2); padding-top: 14px; font-size: 13.5px; color: var(--ink-2); }
.doc-body h4 { font-size: 14px; margin: 18px 0 8px; color: var(--ink); }
.doc-body > p { margin-bottom: 4px; }
.doc-body pre {
  background: #f7f9fd;
  border: 1px solid var(--line);
  border-radius: 10px;
  padding: 12px 14px;
  overflow-x: auto;
  font-family: ui-monospace, SFMono-Regular, Menlo, Consolas, monospace;
  font-size: 12.5px;
  line-height: 1.62;
  color: #2a3a55;
  margin: 0;
}
.doc-tip { margin-top: 12px; font-size: 12.5px; color: var(--muted); }

.table-wrap { overflow-x: auto; margin-top: 8px; }

.doc-table, .record-table {
  width: 100%;
  border-collapse: collapse;
  font-size: 13px;
}

.doc-table th, .doc-table td,
.record-table th, .record-table td {
  border: 1px solid var(--line);
  padding: 7px 10px;
  text-align: left;
  vertical-align: top;
}

.doc-table th, .record-table th { background: #f7f9fd; font-weight: 600; color: var(--ink-2); white-space: nowrap; }

/* ---------------- 练习页 ---------------- */

.practice-head {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 16px;
  padding: 16px 20px;
}

.ph-left h2 { font-size: 17px; }
.ph-meta { font-size: 12.5px; color: var(--muted); margin-top: 2px; }
.dot-sep { margin: 0 5px; }

.ph-right { display: flex; align-items: center; gap: 10px; flex: none; }

.timer {
  display: flex; align-items: baseline; gap: 5px;
  font-size: 12.5px; color: var(--muted);
  background: #f6f8fd;
  border: 1px solid var(--line);
  border-radius: 9px;
  padding: 5px 11px;
}
.timer b { font-size: 14px; font-variant-numeric: tabular-nums; color: var(--ink-2); }

.progress-line { display: flex; align-items: center; gap: 12px; margin: 14px 2px 14px; }

.progress {
  flex: 1;
  height: 6px;
  border-radius: 99px;
  background: #e7ecf6;
  overflow: hidden;
}

.progress-bar {
  height: 100%;
  width: 0;
  border-radius: 99px;
  background: linear-gradient(90deg, #5b85ff, #3d6bf5);
  transition: width .28s ease;
}

.progress-text { font-size: 12.5px; color: var(--muted); flex: none; font-variant-numeric: tabular-nums; }

/* ---------------- 背题搜索栏 ---------------- */

.study-search {
  position: relative;
  display: flex;
  align-items: center;
  gap: 8px;
  background: #fff;
  border: 1.5px solid var(--line);
  border-radius: 12px;
  padding: 8px 12px;
  margin: 0 2px 16px;
  box-shadow: 0 1px 2px rgba(21, 35, 60, .03);
}

.study-search:focus-within { border-color: var(--primary); box-shadow: 0 0 0 3px var(--primary-soft); }

.ss-icon {
  width: 18px;
  height: 18px;
  flex: none;
  color: var(--muted);
}

#study-search-input {
  flex: 1;
  min-width: 0;
  border: none;
  outline: none;
  background: transparent;
  font-size: 14px;
  color: var(--ink);
  font-family: inherit;
}

#study-search-input::placeholder { color: var(--muted); }

.ss-clear {
  flex: none;
  width: 22px;
  height: 22px;
  line-height: 1;
  border: none;
  border-radius: 50%;
  background: #eef2f8;
  color: var(--muted);
  font-size: 15px;
  cursor: pointer;
  padding: 0;
}

.ss-clear:hover { background: var(--bad-soft); color: var(--bad); }

.study-result {
  position: absolute;
  top: calc(100% + 6px);
  left: 0;
  right: 0;
  z-index: 30;
  list-style: none;
  margin: 0;
  padding: 6px;
  max-height: 320px;
  overflow-y: auto;
  background: #fff;
  border: 1px solid var(--line);
  border-radius: 12px;
  box-shadow: var(--shadow);
}

.sr-item {
  display: flex;
  align-items: center;
  gap: 10px;
  padding: 8px 10px;
  border-radius: 8px;
  cursor: pointer;
  font-size: 13.5px;
  color: var(--ink-2);
}

.sr-item:hover { background: var(--primary-soft); }
.sr-item.is-current { background: #eef2fb; }

.sr-no {
  flex: none;
  min-width: 26px;
  height: 22px;
  line-height: 22px;
  text-align: center;
  border-radius: 6px;
  background: #eef2f8;
  color: var(--muted);
  font-size: 12px;
  font-weight: 600;
  font-variant-numeric: tabular-nums;
}

.sr-text {
  flex: 1;
  min-width: 0;
  overflow: hidden;
  text-overflow: ellipsis;
  white-space: nowrap;
  word-break: break-all;
}

.sr-text mark {
  background: #ffe9a8;
  color: inherit;
  border-radius: 3px;
  padding: 0 1px;
}

.sr-tag {
  flex: none;
  font-size: 11.5px;
  color: var(--primary-d);
  background: var(--primary-soft);
  border-radius: 99px;
  padding: 1px 8px;
}

.sr-empty { padding: 14px; text-align: center; color: var(--muted); font-size: 13px; }
.sr-more { padding: 10px; text-align: center; color: var(--muted); font-size: 12.5px; }

.question-card { padding: 20px 22px; }

.q-head { display: flex; align-items: center; gap: 10px; margin-bottom: 12px; flex-wrap: wrap; }

.badge {
  font-size: 12px;
  font-weight: 600;
  padding: 2px 10px;
  border-radius: 99px;
  background: var(--primary-soft);
  color: var(--primary-d);
  border: 1px solid #dbe5ff;
}

.q-index { font-size: 12.5px; color: var(--muted); }
.q-score { font-size: 12.5px; color: var(--muted); margin-left: auto; font-variant-numeric: tabular-nums; }

.q-stem {
  font-size: 16px;
  line-height: 1.75;
  color: var(--ink);
  white-space: pre-wrap;
  word-break: break-word;
  margin-bottom: 16px;
}

.blank-mark { color: var(--primary); font-weight: 600; letter-spacing: 1px; }

.options { display: flex; flex-direction: column; gap: 9px; }

.option {
  display: flex;
  align-items: flex-start;
  gap: 10px;
  text-align: left;
  width: 100%;
  padding: 11px 14px;
  border: 1.5px solid var(--line);
  border-radius: 11px;
  background: #fff;
  color: var(--ink);
  cursor: pointer;
  transition: all .14s ease;
  line-height: 1.6;
}

.option:hover:not(:disabled) { border-color: #b9cbf3; background: #fafcff; }
.option:disabled { cursor: default; }

.opt-mark {
  flex: none;
  width: 22px; height: 22px;
  border-radius: 50%;
  background: #f1f4fa;
  color: #5b6a80;
  font-size: 12.5px;
  font-weight: 650;
  display: flex; align-items: center; justify-content: center;
  margin-top: 1px;
  transition: all .14s ease;
}

.opt-text { flex: 1; word-break: break-word; }

/* 多选保持方形：圆圈=单选、方块=多选，形状即选几个的提示 */
.options.is-multi .opt-mark,
.review-opts.is-multi .opt-mark { border-radius: 6px; }

.option.is-selected { border-color: var(--primary); background: var(--primary-soft); }
.option.is-selected .opt-mark { background: var(--primary); color: #fff; }

.option.is-correct { border-color: var(--ok); background: var(--ok-soft); }
.option.is-correct .opt-mark { background: var(--ok); color: #fff; }

.option.is-wrong { border-color: var(--bad); background: var(--bad-soft); }
.option.is-wrong .opt-mark { background: var(--bad); color: #fff; }

/* 背题模式：选项只用于对照查看，不可点选 */
.options.is-static .option { cursor: default; }
.options.is-static .option:hover { border-color: var(--line); background: #fff; }

/* 填空题 */

.blank-list { display: flex; flex-direction: column; gap: 10px; }

.blank-row { display: flex; align-items: center; gap: 10px; flex-wrap: wrap; }

.blank-no {
  font-size: 12.5px;
  color: var(--muted);
  min-width: 56px;
  flex: none;
}

.blank-input {
  flex: 1;
  min-width: 160px;
  padding: 9px 12px;
  border: 1.5px solid var(--line);
  border-radius: 10px;
  font-size: 14px;
  color: var(--ink);
  background: #fff;
  transition: border-color .15s ease;
  font-family: inherit;
}

.blank-input:focus { outline: none; border-color: var(--primary); box-shadow: 0 0 0 3px rgba(61, 107, 245, .12); }
.blank-input:disabled { background: #f7f9fd; color: var(--ink-2); }

.blank-correct { font-size: 12.5px; color: var(--ok); }

/* 背题模式：答案区 */

.answer-panel {
  margin-top: 16px;
  border: 1px solid var(--ok-line);
  border-radius: 12px;
  padding: 13px 15px;
  background: var(--ok-soft);
}

.ans-head {
  display: flex;
  align-items: baseline;
  gap: 8px;
  flex-wrap: wrap;
  line-height: 1.6;
}

.ans-head .k, .ans-exp .k {
  flex: none;
  min-width: 64px;
  font-size: 12.5px;
  color: var(--muted);
}

.ans-value { font-size: 15px; font-weight: 650; color: #0d7550; }

.ans-exp { display: flex; gap: 8px; margin-top: 8px; font-size: 13.5px; }
.ans-exp p { flex: 1; color: var(--ink-2); white-space: pre-wrap; }

/* 判题反馈 */

.feedback {
  margin-top: 16px;
  border-radius: 12px;
  padding: 13px 15px;
  border: 1px solid var(--line);
  background: #f8fafd;
}

.feedback.is-ok { border-color: var(--ok-line); background: var(--ok-soft); }
.feedback.is-bad { border-color: var(--bad-line); background: var(--bad-soft); }

.fb-head {
  display: flex;
  align-items: center;
  gap: 8px;
  font-weight: 650;
  font-size: 14px;
  margin-bottom: 7px;
}

.feedback.is-ok .fb-head { color: #0d7550; }
.feedback.is-bad .fb-head { color: #a8342f; }

.fb-score { margin-left: auto; font-size: 12.5px; font-weight: 550; color: var(--ink-2); }

.fb-line { display: flex; gap: 8px; font-size: 13.5px; line-height: 1.7; flex-wrap: wrap; }
.fb-line .k, .fb-exp .k, .review-answers .k, .review-exp .k {
  color: var(--muted);
  font-size: 12.5px;
  flex: none;
  min-width: 64px;
}
.fb-line b { font-weight: 550; color: var(--ink); }

.fb-exp { margin-top: 6px; display: flex; gap: 8px; font-size: 13.5px; }
.fb-exp p { white-space: pre-wrap; color: var(--ink-2); flex: 1; }

/* 选项被打乱时，解析前的原顺序对照 */
.origin-order {
  display: flex;
  gap: 8px;
  margin-top: 10px;
  padding: 8px 11px;
  border: 1px dashed #cdd9ec;
  border-radius: 9px;
  background: #fff;
  font-size: 13px;
  line-height: 1.7;
  color: var(--ink-2);
}

.origin-order .k {
  flex: none;
  min-width: 64px;
  font-size: 12.5px;
  color: var(--muted);
}

.origin-order .v { flex: 1; min-width: 0; }

.origin-tip {
  margin: 6px 0 0;
  font-size: 12px;
  color: var(--muted);
  line-height: 1.55;
}

.q-actions {
  display: flex;
  align-items: center;
  gap: 10px;
  margin-top: 18px;
  padding-top: 16px;
  border-top: 1px solid var(--line-2);
}

.q-actions .btn-primary { margin-left: auto; min-width: 118px; }

.kbd-tip { margin-top: 10px; font-size: 11.5px; color: #a2adbd; text-align: right; }

/* 答题卡 */

.sheet { position: sticky; top: 78px; }

.sheet-grid {
  --sheet-cell-min: 32px;
  --sheet-gap: 6px;
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(var(--sheet-cell-min), 1fr));
  gap: var(--sheet-gap);
}

.sheet-pager {
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 10px;
  margin-top: 10px;
}

.sheet-page-btn {
  width: 34px;
  height: 28px;
  padding: 0;
  border: 1px solid var(--line);
  border-radius: 8px;
  background: #fff;
  color: var(--ink-2);
  font-size: 16px;
  line-height: 1;
  cursor: pointer;
  transition: all .14s ease;
}

.sheet-page-btn:hover:not(:disabled) { border-color: #b9cbf3; color: var(--primary-d); }
.sheet-page-btn:disabled { opacity: .4; cursor: default; }

.sheet-page-info {
  min-width: 52px;
  text-align: center;
  font-size: 12px;
  color: var(--muted);
  font-variant-numeric: tabular-nums;
}

.sheet-cell {
  height: 32px;
  padding: 0;
  border: 1px solid var(--line);
  border-radius: 8px;
  background: #fff;
  color: var(--ink-2);
  font-size: 12.5px;
  font-variant-numeric: tabular-nums;
  cursor: pointer;
  transition: all .14s ease;
}

.sheet-cell:hover { border-color: #b9cbf3; color: var(--primary-d); }
.sheet-cell.is-done { background: #eef2fb; border-color: #d8e2f7; color: #41527a; }
.sheet-cell.is-ok { background: var(--ok-soft); border-color: var(--ok-line); color: #0d7550; }
.sheet-cell.is-bad { background: var(--bad-soft); border-color: var(--bad-line); color: #a8342f; }
.sheet-cell.is-current { border-color: var(--primary); box-shadow: 0 0 0 2px rgba(61, 107, 245, .18); font-weight: 650; }

.sheet-legend {
  display: flex;
  flex-wrap: wrap;
  gap: 10px;
  margin-top: 13px;
  font-size: 11.5px;
  color: var(--muted);
}
.sheet-legend span { display: flex; align-items: center; gap: 4px; }

/* 背题模式没有正误状态，图例只保留「当前 / 已看」 */
.sheet.is-study .lg-ok,
.sheet.is-study .lg-bad { display: none; }

.dot { width: 9px; height: 9px; border-radius: 3px; display: inline-block; border: 1px solid transparent; }
.dot-cur { border-color: var(--primary); background: #fff; box-shadow: 0 0 0 2px rgba(61, 107, 245, .18); }
.dot-done { background: #eef2fb; border-color: #d8e2f7; }
.dot-ok { background: var(--ok-soft); border-color: var(--ok-line); }
.dot-bad { background: var(--bad-soft); border-color: var(--bad-line); }

.sheet-stat { font-size: 12.5px; color: var(--muted); margin: 12px 0 10px; }

/* ---------------- 成绩页 ---------------- */

.result-hero {
  display: flex;
  align-items: center;
  gap: 24px;
  flex-wrap: wrap;
  padding: 22px;
}

.ring-wrap { position: relative; width: 130px; height: 130px; flex: none; }
.ring { width: 130px; height: 130px; transform: rotate(-90deg); }

.ring-bg { fill: none; stroke: #eaeff8; stroke-width: 11; }
.ring-fill {
  fill: none;
  stroke: var(--primary);
  stroke-width: 11;
  stroke-linecap: round;
  stroke-dasharray: 339.29;
  stroke-dashoffset: 339.29;
  transition: stroke-dashoffset .8s cubic-bezier(.22, .8, .3, 1);
}
.ring-fill.is-low { stroke: #e0883b; }
.ring-fill.is-bad { stroke: var(--bad); }

.ring-text {
  position: absolute;
  inset: 0;
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  gap: 1px;
}
.ring-text strong { font-size: 27px; line-height: 1.1; font-variant-numeric: tabular-nums; }
.ring-text span { font-size: 11.5px; color: var(--muted); }

.result-main { flex: 1; min-width: 240px; }
.result-main h2 { font-size: 19px; }
.result-sub { font-size: 13px; color: var(--muted); margin-top: 2px; }

.result-stats { display: flex; flex-wrap: wrap; gap: 26px; margin-top: 14px; }
.rstat { display: flex; flex-direction: column; gap: 1px; }
.rstat span { font-size: 12px; color: var(--muted); }
.rstat b { font-size: 16px; font-variant-numeric: tabular-nums; }

.result-actions { display: flex; flex-direction: column; gap: 8px; flex: none; }
.result-actions .btn { min-width: 132px; }

.tabs { display: flex; gap: 6px; flex-wrap: wrap; padding-bottom: 14px; border-bottom: 1px solid var(--line-2); margin-bottom: 4px; }

.tab {
  border: 1px solid transparent;
  background: transparent;
  color: var(--ink-2);
  border-radius: 9px;
  padding: 6px 13px;
  font-size: 13.5px;
  cursor: pointer;
  transition: all .14s ease;
}

.tab:hover { background: #f5f8fd; }
.tab.is-active { background: var(--primary-soft); color: var(--primary-d); font-weight: 600; border-color: #dbe5ff; }
.tab i { font-style: normal; font-size: 11.5px; opacity: .75; margin-left: 2px; }

.recap { margin: 10px 0 4px; }
.recap > summary {
  cursor: pointer;
  font-size: 13px;
  color: var(--muted);
  padding: 6px 0;
  list-style: none;
}
.recap > summary::-webkit-details-marker { display: none; }
.recap > summary::before { content: "▸ "; }
.recap[open] > summary::before { content: "▾ "; }

.record-table td.num { text-align: center; color: var(--muted); font-variant-numeric: tabular-nums; }
.record-table td.res-ok { color: var(--ok); font-weight: 600; }
.record-table td.res-bad { color: var(--bad); font-weight: 600; }

.review-list { display: flex; flex-direction: column; gap: 12px; margin-top: 14px; }

.review-item {
  border: 1px solid var(--line);
  border-radius: 12px;
  padding: 15px 17px;
  background: #fff;
}
.review-item.is-bad { border-left: 3px solid var(--bad); }
.review-item.is-ok { border-left: 3px solid var(--ok); }
.review-item.is-skip { border-left: 3px solid #c8d2e2; }

.review-head { display: flex; align-items: center; gap: 9px; flex-wrap: wrap; margin-bottom: 8px; }
.review-no { font-size: 12.5px; color: var(--muted); font-variant-numeric: tabular-nums; }

.tag {
  font-size: 11.5px;
  font-weight: 600;
  padding: 1px 8px;
  border-radius: 99px;
}
.tag-ok { background: var(--ok-soft); color: #0d7550; }
.tag-bad { background: var(--bad-soft); color: #a8342f; }
.tag-skip { background: #f1f4f9; color: #6b7889; }
.review-score { margin-left: auto; font-size: 12.5px; color: var(--muted); font-variant-numeric: tabular-nums; }

.review-stem { font-size: 14.5px; line-height: 1.7; white-space: pre-wrap; word-break: break-word; margin-bottom: 10px; }

.review-opts { display: flex; flex-direction: column; gap: 4px; margin-bottom: 10px; }

.ropt {
  display: flex;
  gap: 8px;
  font-size: 13.5px;
  color: var(--ink-2);
  padding: 4px 9px;
  border-radius: 8px;
  line-height: 1.6;
}
.ropt .opt-mark { width: 19px; height: 19px; font-size: 11.5px; margin-top: 0; }
.ropt.is-correct { background: var(--ok-soft); color: #0d7550; }
.ropt.is-correct .opt-mark { background: var(--ok); color: #fff; }
.ropt.is-wrong { background: var(--bad-soft); color: #a8342f; }
.ropt.is-wrong .opt-mark { background: var(--bad); color: #fff; }

.review-answers {
  display: flex;
  flex-direction: column;
  gap: 3px;
  font-size: 13.5px;
  padding: 9px 11px;
  background: #f8fafd;
  border-radius: 9px;
}
.review-answers > div { display: flex; gap: 8px; flex-wrap: wrap; }
.review-answers .v { font-weight: 550; }
.review-answers .v.ok { color: var(--ok); }
.review-answers .v.bad { color: var(--bad); }
.review-answers .v.skip { color: var(--muted); font-weight: 400; }

.review-exp { display: flex; gap: 8px; margin-top: 9px; font-size: 13.5px; }
.review-exp p { flex: 1; color: var(--ink-2); white-space: pre-wrap; }

.empty-rev { text-align: center; color: var(--muted); font-size: 13.5px; padding: 26px 0; }

/* ---------------- 响应式 ---------------- */

@media (max-width: 900px) {
  .upload-grid, .practice-body { grid-template-columns: 1fr; }
  .settings, .sheet { position: static; }
  .result-actions { flex-direction: row; flex-wrap: wrap; width: 100%; }
  .result-actions .btn { flex: 1; min-width: 110px; }
  .hero h1 { font-size: 21px; }
}

@media (max-width: 560px) {
  .container { padding: 18px 13px 60px; }
  .topbar-inner { padding: 11px 14px; }
  .brand-text span { display: none; }
  .step { padding: 4px 8px; font-size: 12px; }
  .steps .step span { display: none; }
  .card { padding: 16px; }
  .question-card { padding: 17px; }
  .q-stem { font-size: 15px; }
  .result-hero { gap: 16px; }
  .ring-wrap, .ring { width: 108px; height: 108px; }
  .result-stats { gap: 18px; }
  .kbd-tip { display: none; }

  /* iOS 上输入框字号小于 16px 会在聚焦时强制放大页面 */
  .blank-input { font-size: 16px; }
  .option { padding: 12px 13px; }
  .sheet-cell { height: 36px; }
  .btn { padding: 10px 15px; }

  /* 上传操作区：主行动独占一行，两个次要按钮均分，避免 2+1 的折行 */
  .upload-actions { gap: 8px; }
  .upload-actions .btn { min-height: 42px; }
  .upload-actions .btn-online { flex: 1 1 100%; }
  .upload-actions .btn-ghost {
    flex: 1 1 calc(50% - 4px);
    padding-left: 8px;
    padding-right: 8px;
    font-size: 13px;
  }
}