/* 演示页样式。
   【为什么单独一个文件】跟 landing.css 同样的道理：style.css 是站内所有页面共用的，
   演示页那一堆 .dm-* 是画"假界面"用的，混进去以后改站内样式容易连带改坏演示画面。
   色值全部取 style.css :root 里的变量 —— 真实界面调了主色，演示画面跟着变。 */

.demo-body { background: var(--bg); margin: 0; }

.demo-wrap {
  display: grid; grid-template-columns: minmax(0, 1fr) 280px;
  gap: 22px; max-width: 1240px; margin: 0 auto; padding: 22px 20px 48px;
  align-items: start;
}
.demo-main { min-width: 0; }   /* 不加这句，里面 16:9 的画面会把栅格撑破 */

/* ---------- 播放器外框 ---------- */
.dm-player {
  background: var(--card); border: 1px solid var(--border);
  border-radius: var(--radius); box-shadow: var(--shadow); overflow: hidden;
}
.dm-screen {
  position: relative; width: 100%; aspect-ratio: 16 / 9;
  background: var(--bg); overflow: hidden;
}
/* aspect-ratio 老浏览器不支持，退回 padding-top 撑高度 */
@supports not (aspect-ratio: 1) {
  .dm-screen { height: 0; padding-top: 56.25%; }
}
.dm-stage { position: absolute; inset: 0; }
.dm-stage.dm-in { animation: dmIn .28s ease-out; }
@keyframes dmIn { from { opacity: 0; transform: translateY(6px); } to { opacity: 1; transform: none; } }

.dm-realvideo { display: block; width: 100%; height: auto; background: #000; }

/* ---------- 开场遮罩 ---------- */
.dm-poster {
  position: absolute; inset: 0; z-index: 6;
  display: flex; flex-direction: column; align-items: center; justify-content: center; gap: 14px;
  background: linear-gradient(160deg, rgba(10, 31, 68, .93), rgba(18, 44, 94, .93));
  color: #fff; transition: opacity .25s;
}
.dm-poster.dm-hide { opacity: 0; pointer-events: none; }
.dm-play-big {
  width: 66px; height: 66px; border-radius: 50%; border: 0; cursor: pointer;
  background: #fff; display: flex; align-items: center; justify-content: center;
  box-shadow: 0 8px 30px rgba(0, 0, 0, .3);
}
.dm-play-big:hover { transform: scale(1.06); }
.dm-tri {
  width: 0; height: 0; border-style: solid;
  border-width: 9px 0 9px 15px; border-color: transparent transparent transparent var(--primary);
  margin-left: 3px;
}
.dm-poster-txt { text-align: center; line-height: 1.7; }
.dm-poster-txt b { display: block; font-size: 17px; }
.dm-poster-txt span { font-size: 12.5px; opacity: .78; }

/* ---------- 假鼠标 ---------- */
.dm-cursor {
  position: absolute; z-index: 5; width: 18px; height: 18px; display: none;
  margin: -2px 0 0 -2px; pointer-events: none;
  transition: left .55s cubic-bezier(.22, .61, .36, 1), top .55s cubic-bezier(.22, .61, .36, 1);
  /* 用 SVG 画箭头：字符 ➤ 在不同系统字体里形状差别很大，SVG 到处一样 */
  background: no-repeat center/contain
    url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' viewBox='0 0 24 24'%3E%3Cpath d='M5 2l14 9-6 1 3 7-3 1-3-7-5 4z' fill='%23fff' stroke='%23111' stroke-width='1.4'/%3E%3C/svg%3E");
}
/* 点击动效：在鼠标位置涨一圈波纹。用 ::after 不额外加 DOM。 */
.dm-cursor.dm-click::after {
  content: ''; position: absolute; left: -11px; top: -11px;
  width: 34px; height: 34px; border-radius: 50%;
  border: 2px solid var(--primary); animation: dmPing 1.1s ease-out infinite;
}
@keyframes dmPing {
  0% { transform: scale(.35); opacity: .9; }
  100% { transform: scale(1); opacity: 0; }
}

/* ---------- 字幕与控制条 ---------- */
.dm-caption {
  padding: 12px 16px; font-size: 14px; line-height: 1.6; color: var(--text);
  background: #f8fafd; border-top: 1px solid var(--border);
  /* 【为什么定死两行高】字幕长短不一，不定高的话每换一步整页都上下跳一下。 */
  min-height: 46px; display: flex; align-items: center;
}
.dm-controls {
  display: flex; align-items: center; gap: 10px;
  padding: 10px 14px; border-top: 1px solid var(--border);
}
.dm-ico {
  width: 32px; height: 32px; border-radius: 8px; cursor: pointer;
  border: 1px solid var(--border); background: #fff; color: var(--text);
  display: flex; align-items: center; justify-content: center; font-size: 14px;
}
.dm-ico:hover { border-color: var(--primary); color: var(--primary); }
.dm-ico .dm-tri { border-width: 6px 0 6px 10px; }
/* 播放中显示"暂停"两条竖杠：把三角换成两条 border */
.dm-player.dm-playing #playBtn .dm-tri {
  border: 0; width: 9px; height: 11px; margin: 0;
  border-left: 3px solid var(--primary); border-right: 3px solid var(--primary);
}
.dm-speed { width: auto; padding: 0 9px; font-size: 12px; font-variant-numeric: tabular-nums; }
.dm-seek { flex: 1; accent-color: var(--primary); cursor: pointer; min-width: 0; }
.dm-time { font-size: 12px; color: var(--muted); font-variant-numeric: tabular-nums; white-space: nowrap; }

/* ---------- 右侧章节 / 底部清单 ---------- */
.dm-side {
  background: var(--card); border: 1px solid var(--border);
  border-radius: var(--radius); box-shadow: var(--shadow); overflow: hidden;
  position: sticky; top: 18px;
}
.dm-side-head {
  padding: 13px 16px; font-weight: 600; font-size: 14px;
  border-bottom: 1px solid var(--border); background: #f8fafd;
}
.dm-chapters { list-style: none; margin: 0; padding: 6px; }
.dm-chapters li {
  display: flex; align-items: center; gap: 10px; cursor: pointer;
  padding: 9px 10px; border-radius: 9px; font-size: 13.5px; color: var(--text);
}
.dm-chapters li:hover { background: #eef4ff; }
.dm-chapters li.on { background: #e8f0ff; color: var(--primary); font-weight: 600; }
.dm-chapters li i {
  font-style: normal; font-size: 11.5px; color: var(--muted);
  font-variant-numeric: tabular-nums; min-width: 30px;
}
.dm-chapters li.on i { color: var(--primary); }
.dm-tip {
  margin: 4px 12px 14px; padding: 11px 12px; border-radius: 10px;
  background: #f8fafd; border: 1px solid var(--border);
  font-size: 12.5px; line-height: 1.65; color: var(--muted);
}
.dm-tip b { display: block; color: var(--text); margin-bottom: 3px; }

.dm-notes {
  margin-top: 18px; background: var(--card); border: 1px solid var(--border);
  border-radius: var(--radius); box-shadow: var(--shadow); padding: 16px 18px;
}
.dm-notes-h { font-weight: 600; font-size: 15px; margin-bottom: 10px; }
.dm-notes ul { margin: 0; padding-left: 20px; }
.dm-notes li { font-size: 13.5px; line-height: 1.85; color: var(--muted); }

/* ---------- 假界面：通用 ---------- */
/* 【为什么整体缩放而不是把字号都写小】画面是 16:9 的框，真实界面按原尺寸画进去
   会挤成一团。这里按真实比例画，再用 zoom 整体缩 —— 布局关系跟真界面一致，
   改真界面时照搬 class 就行。zoom 不是标准属性但三大浏览器都支持，
   transform:scale 会留出空白且要自己算 width，反而更麻烦。 */
.dm-page {
  position: absolute; inset: 0; zoom: .62;
  width: 161.3%; height: 161.3%;   /* 1/.62，补回缩放后的可用空间 */
  background: var(--bg); font-size: 14px; color: var(--text); overflow: hidden;
}
.dm-center { display: flex; align-items: center; justify-content: center; }
.dm-dim { background: rgba(10, 31, 68, .35); }

.dm-top {
  display: flex; align-items: center; gap: 9px;
  padding: 12px 20px; background: var(--card); border-bottom: 1px solid var(--border);
}
.dm-logo {
  width: 24px; height: 24px; border-radius: 6px; background: var(--primary);
  color: #fff; font-size: 13px; display: flex; align-items: center; justify-content: center;
}
.dm-div { width: 1px; height: 18px; background: var(--border); margin: 0 3px; }
.dm-topname { font-size: 14px; font-weight: 600; }
.dm-topsub { font-size: 12px; color: var(--muted); }
.dm-topright { margin-left: auto; display: flex; gap: 8px; align-items: center; }
.dm-muted2 { font-size: 12.5px; color: var(--muted); }

.dm-row2 { display: flex; align-items: stretch; height: calc(100% - 49px); }
.dm-nav {
  width: 172px; flex: none; background: var(--card);
  border-right: 1px solid var(--border); padding: 12px 10px;
}
.dm-navitem {
  display: flex; align-items: center; gap: 10px; padding: 9px 11px;
  border-radius: 9px; font-size: 13.5px; color: var(--muted); margin-bottom: 2px;
}
.dm-navitem i { font-style: normal; width: 16px; text-align: center; }
.dm-navitem.on { background: #e8f0ff; color: var(--primary); font-weight: 600; }
.dm-body { flex: 1; padding: 18px 22px; min-width: 0; overflow: hidden; }

/* ---------- 假界面：卡片 / 列表 ---------- */
.dm-hero {
  background: linear-gradient(120deg, var(--navy), var(--navy-2));
  color: #fff; border-radius: 12px; padding: 16px 18px; margin-bottom: 16px;
}
.dm-hero b { display: block; font-size: 19px; }
.dm-hero span { font-size: 12.5px; opacity: .8; }
.dm-sec { font-size: 15px; font-weight: 600; margin: 14px 0 9px; }
.dm-sec2 { font-size: 13px; font-weight: 600; margin-bottom: 8px; }
.dm-cards { display: flex; gap: 12px; flex-wrap: wrap; }
.dm-card {
  flex: 1 1 230px; background: var(--card); border: 1px solid var(--border);
  border-radius: 11px; padding: 14px;
}
.dm-card.on { border-color: var(--primary); box-shadow: 0 0 0 3px rgba(27, 102, 240, .1); }
.dm-card-t { font-size: 14px; font-weight: 600; margin-bottom: 5px; }
.dm-card-m { font-size: 12.5px; color: var(--muted); margin-bottom: 11px; }
.dm-line {
  display: flex; align-items: center; gap: 9px; padding: 10px 13px;
  background: var(--card); border: 1px solid var(--border);
  border-radius: 9px; margin-bottom: 7px; font-size: 13.5px;
}
.dm-tagm { margin-left: auto; font-size: 12px; color: var(--muted); }
.dm-ok { color: var(--ok); font-weight: 700; }
.dm-bad { color: var(--bad); font-weight: 700; }
.dm-warn { color: var(--warn); }
.dm-badtxt { color: var(--bad); }
.dm-pend { opacity: .75; }

/* ---------- 假界面：按钮 / 输入 ---------- */
.dm-btn {
  display: inline-flex; align-items: center; justify-content: center;
  padding: 9px 15px; border-radius: 9px; font-size: 13px;
  border: 1px solid var(--border); background: #fff; color: var(--text);
}
.dm-btn-pri { background: var(--primary); border-color: var(--primary); color: #fff; }
.dm-btn-bad { background: var(--bad); border-color: var(--bad); color: #fff; }
.dm-btn-sm { padding: 6px 12px; font-size: 12.5px; }
.dm-btn-w { width: 100%; }
.dm-btnrow { display: flex; gap: 10px; }
.dm-input {
  padding: 11px 13px; border: 1px solid var(--border); border-radius: 9px;
  background: #fff; color: var(--muted); font-size: 13.5px; margin-bottom: 10px;
}

/* ---------- 假界面：登录 ---------- */
.dm-loginbox {
  width: 390px; background: var(--card); border: 1px solid var(--border);
  border-radius: 14px; padding: 26px 26px 24px; box-shadow: var(--shadow);
}
.dm-brandrow { display: flex; align-items: center; gap: 8px; font-size: 16px; margin-bottom: 12px; }
.dm-h2 { font-size: 17px; font-weight: 600; margin-bottom: 6px; }
.dm-muted { font-size: 12.5px; color: var(--muted); line-height: 1.7; margin: 0 0 16px; }
.dm-rolerow { display: flex; gap: 11px; }
.dm-role {
  flex: 1; border: 1px solid var(--border); border-radius: 11px;
  padding: 15px 12px; text-align: center; background: #fff;
}
.dm-role.on { border-color: var(--primary); background: #f2f7ff; box-shadow: 0 0 0 3px rgba(27, 102, 240, .1); }
.dm-role i { font-style: normal; font-size: 20px; display: block; margin-bottom: 6px; }
.dm-role b { display: block; font-size: 13.5px; }
.dm-role span { font-size: 11.5px; color: var(--muted); }
.dm-tabs { display: flex; gap: 16px; border-bottom: 1px solid var(--border); margin-bottom: 16px; }
.dm-tabs span { padding-bottom: 8px; font-size: 13.5px; color: var(--muted); }
.dm-tabs span.on { color: var(--primary); font-weight: 600; box-shadow: inset 0 -2px 0 var(--primary); }

/* ---------- 假界面：弹窗 ---------- */
.dm-modal {
  width: 440px; background: var(--card); border-radius: 14px;
  padding: 24px 26px; box-shadow: 0 20px 60px rgba(10, 31, 68, .3);
}
.dm-modal-bad { border-top: 4px solid var(--bad); }
.dm-rules { margin: 12px 0 18px; padding-left: 20px; }
.dm-rules li { font-size: 13px; line-height: 1.95; color: var(--muted); }
.dm-rules b { color: var(--text); }

/* ---------- 假界面：考试中 ---------- */
.dm-examtop { border-bottom: 0; }
.dm-timer {
  padding: 5px 12px; border-radius: 999px; background: #fff2e0;
  color: var(--warn); font-size: 13px; font-weight: 600;
  font-variant-numeric: tabular-nums;
}
.dm-prog { height: 3px; background: var(--border); }
.dm-prog i { display: block; height: 100%; background: var(--primary); }
.dm-palette {
  width: 196px; flex: none; background: var(--card);
  border-right: 1px solid var(--border); padding: 14px 13px;
}
.dm-pgrid { display: grid; grid-template-columns: repeat(5, 1fr); gap: 6px; margin-bottom: 13px; }
.dm-pn {
  height: 27px; border-radius: 7px; border: 1px solid var(--border);
  display: flex; align-items: center; justify-content: center;
  font-size: 12px; color: var(--muted); background: #fff;
}
.dm-pn.done { background: #e8f0ff; border-color: #bcd4ff; color: var(--primary); }
.dm-pn.cur { background: var(--primary); border-color: var(--primary); color: #fff; font-weight: 600; }
.dm-q { background: var(--card); border: 1px solid var(--border); border-radius: 12px; padding: 18px; }
.dm-qh { display: flex; align-items: center; gap: 9px; margin-bottom: 11px; }
.dm-tag {
  padding: 3px 9px; border-radius: 6px; background: #e8f0ff;
  color: var(--primary); font-size: 11.5px; font-weight: 600;
}
.dm-qt { font-size: 15px; line-height: 1.65; margin-bottom: 15px; }
.dm-opt {
  display: flex; align-items: center; gap: 11px; padding: 11px 14px;
  border: 1px solid var(--border); border-radius: 10px;
  margin-bottom: 9px; font-size: 13.5px; background: #fff;
}
.dm-opt i {
  font-style: normal; width: 22px; height: 22px; flex: none; border-radius: 50%;
  border: 1px solid var(--border); display: flex; align-items: center;
  justify-content: center; font-size: 11.5px; color: var(--muted);
}
.dm-opt.on { border-color: var(--primary); background: #f2f7ff; }
.dm-opt.on i { background: var(--primary); border-color: var(--primary); color: #fff; }
.dm-cam {
  position: absolute; right: 20px; bottom: 18px;
  display: flex; align-items: center; gap: 6px;
  padding: 7px 12px; border-radius: 999px; background: rgba(10, 31, 68, .82);
  color: #fff; font-size: 12px;
}
.dm-camdot { color: #ff5b5b; animation: dmBlink 1.4s infinite; }
@keyframes dmBlink { 50% { opacity: .25; } }

/* ---------- 假界面：成绩 / 成长 ---------- */
.dm-score {
  display: flex; align-items: center; gap: 14px;
  background: linear-gradient(120deg, var(--navy), var(--navy-2));
  color: #fff; border-radius: 12px; padding: 18px 20px;
}
.dm-score b { font-size: 38px; line-height: 1; font-variant-numeric: tabular-nums; }
.dm-pass {
  padding: 4px 11px; border-radius: 999px;
  background: rgba(22, 163, 74, .9); font-size: 12.5px;
}
.dm-score .dm-muted2 { color: rgba(255, 255, 255, .75); margin-left: auto; }
.dm-bars { display: flex; align-items: flex-end; gap: 16px; height: 118px; padding: 0 4px; }
.dm-bars i {
  position: relative; flex: 1; background: #cfe0ff; border-radius: 7px 7px 0 0;
}
.dm-bars i.on { background: var(--primary); }
.dm-bars b {
  position: absolute; top: -19px; left: 0; right: 0; text-align: center;
  font-size: 12px; color: var(--muted); font-weight: 600;
}
.dm-bars i.on b { color: var(--primary); }

/* ---------- 窄屏 ---------- */
/* 章节列表挪到画面下面。手机上 280px 的侧栏会把 16:9 画面压得没法看。 */
@media (max-width: 900px) {
  .demo-wrap { grid-template-columns: 1fr; padding: 14px 12px 36px; }
  .dm-side { position: static; }
  .dm-caption { font-size: 13.5px; }
}
@media (max-width: 560px) {
  /* 手机上假界面还要再缩，不然侧栏 + 答题卡两列挤不下 */
  .dm-page { zoom: .42; width: 238%; height: 238%; }
  .dm-controls { flex-wrap: wrap; }
  .dm-seek { order: 9; flex-basis: 100%; }
}