:root {
  --bg: #eef1f5;
  --paper: #ffffff;
  --ink: #20242a;
  --sub: #65707c;
  --muted: #99a2ad;
  --line: #e7ebf0;
  --orange: #ff7a2f;
  --orange-soft: #fff1e8;
  --blue: #247cff;
  --teal: #13b8ad;
  --green: #2dbd73;
  --purple: #6254e8;
  --shadow: 0 16px 45px rgba(21, 34, 51, 0.1);
  font-family: -apple-system, BlinkMacSystemFont, "SF Pro Display", "PingFang SC", "Helvetica Neue", Arial, sans-serif;
}

* { box-sizing: border-box; }
body { margin: 0; color: var(--ink); background: var(--bg); }
button, input { font: inherit; }
button {
  height: 36px;
  padding: 0 16px;
  border: 0;
  background: #fff;
  color: var(--orange);
  font-weight: 700;
}
button.primary, .primary { background: var(--orange); color: #fff; }
a { color: var(--orange); text-decoration: none; }

.prototype-board { padding: 28px 34px 60px; }
.board-head {
  max-width: 1420px;
  margin: 0 auto 26px;
  display: flex;
  align-items: end;
  justify-content: space-between;
}
.board-head h1 { margin: 0; font-size: 30px; letter-spacing: 0; }
.board-head p, .board-head span { margin: 6px 0 0; color: var(--muted); }
.phone-grid {
  max-width: 1420px;
  margin: 0 auto;
  display: grid;
  grid-template-columns: repeat(3, 390px);
  gap: 32px 42px;
}
.shot-label {
  height: 50px;
  display: flex;
  align-items: end;
  justify-content: space-between;
  padding: 0 2px 10px;
}
.shot-label strong { font-size: 18px; }
.shot-label span { color: var(--muted); font-size: 13px; }
.phone {
  position: relative;
  width: 390px;
  height: 844px;
  overflow: hidden;
  background: #f4f6f9;
  border: 10px solid #15181d;
  border-radius: 34px;
  box-shadow: var(--shadow);
}
.status {
  height: 34px;
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 0 18px;
  background: #fff;
  font-size: 12px;
  font-weight: 800;
}
.status i {
  width: 54px;
  height: 12px;
  border-radius: 99px;
  background: linear-gradient(90deg, #222 0 28px, transparent 29px 34px, #222 35px);
}
.status.dark { color: #fff; background: #10151d; }
.status.dark i { background: linear-gradient(90deg, #fff 0 28px, transparent 29px 34px, #fff 35px); }

.login-screen { background: #fff; }
.login-box { padding: 54px 32px 0; }
.logo {
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 12px;
  margin: 28px 0 80px;
  font-size: 24px;
  font-weight: 900;
}
.logo span, .brand-mark {
  width: 44px;
  height: 44px;
  display: grid;
  place-items: center;
  border-radius: 12px;
  color: #fff;
  background: conic-gradient(from 140deg, #1b8cff, #13b78f, #ff7a2f, #1b8cff);
}
.login-tabs {
  display: flex;
  justify-content: center;
  gap: 54px;
  margin-bottom: 24px;
  color: var(--muted);
  font-size: 17px;
}
.login-tabs b { padding-bottom: 8px; border-bottom: 3px solid transparent; }
.login-tabs .active { color: #5a6ee8; border-bottom-color: #5a6ee8; }
.login-box label {
  height: 58px;
  display: flex;
  align-items: center;
  gap: 12px;
  margin-bottom: 12px;
  padding: 0 16px;
  background: #f6f7fb;
}
.login-box label span { width: 52px; color: var(--muted); }
.login-box input { flex: 1; min-width: 0; border: 0; background: transparent; outline: 0; font-size: 16px; }
.login-links { display: flex; justify-content: space-between; margin: 16px 0 38px; }
.full { width: 100%; height: 50px; font-size: 18px; }
.agreement {
  position: absolute;
  left: 32px;
  right: 32px;
  bottom: 44px;
  display: flex;
  align-items: center;
  gap: 8px;
  color: var(--sub);
  font-size: 13px;
}
.agreement i { width: 20px; height: 20px; border: 1px solid var(--line); }

.app-head, .simple-head {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 18px 18px 10px;
  background: #fff;
}
.app-head span { color: var(--muted); }
.app-head h2, .simple-head h2, .center-head h2 { margin: 4px 0 0; font-size: 24px; letter-spacing: 0; }
.round, .icon-btn {
  width: 36px;
  height: 36px;
  padding: 0;
  border-radius: 50%;
  background: #f3f5f8;
  color: var(--sub);
}
.hero-card {
  margin: 8px 16px 12px;
  padding: 18px;
  color: #fff;
  background:
    radial-gradient(circle at 84% 20%, rgba(255,255,255,.28), transparent 80px),
    linear-gradient(135deg, #ff7a2f, #f4ad36);
}
.hero-card h3 { margin: 10px 0 8px; font-size: 23px; }
.hero-card p { margin: 0 0 14px; opacity: .9; }
.hero-card > span, .tag {
  display: inline-block;
  padding: 3px 8px;
  font-size: 12px;
  font-weight: 700;
}
.hero-card > span { color: #fff; background: rgba(255,255,255,.22); }
.tag.orange { color: var(--orange); background: var(--orange-soft); }
.tag.blue { color: var(--blue); background: #eaf3ff; }
.tag.green { color: var(--green); background: #eafaf1; }
.progress {
  height: 7px;
  overflow: hidden;
  background: rgba(255,255,255,.38);
}
.progress i { display: block; height: 100%; background: #fff; }
.hero-card div:last-child {
  display: flex;
  align-items: center;
  justify-content: space-between;
  margin-top: 14px;
}
.hero-card b { font-size: 26px; }
.hero-card button { color: var(--orange); }
.quick-row {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 8px;
  padding: 0 16px;
}
.quick-row a {
  padding: 12px 8px;
  text-align: center;
  background: #fff;
  color: var(--muted);
}
.quick-row b { display: block; color: var(--ink); font-size: 19px; }

.section { padding: 14px 16px 0; }
.section.no-pad { padding-top: 10px; }
.section-title {
  display: flex;
  align-items: center;
  justify-content: space-between;
  margin-bottom: 12px;
}
.section-title h3 { margin: 0; font-size: 19px; }
.task-list article, .file-list article, .record-list article, .menu-list a {
  padding: 14px;
  margin-bottom: 10px;
  background: #fff;
  border: 1px solid var(--line);
}
.task-list b, .record-list b { display: block; margin: 8px 0 5px; font-size: 16px; }
.task-list p, .record-list p, .file-list p { margin: 0; color: var(--muted); }

.course-scroll {
  display: flex;
  gap: 12px;
  overflow: hidden;
}
.course-scroll article {
  width: 168px;
  flex: 0 0 168px;
  background: #fff;
  border: 1px solid var(--line);
}
.course-scroll b, .course-grid b { display: block; padding: 10px 10px 5px; font-size: 14px; line-height: 1.35; }
.course-scroll p, .course-grid p { margin: 0; padding: 0 10px 12px; color: var(--muted); font-size: 12px; }
.cover {
  height: 88px;
  display: flex;
  align-items: center;
  justify-content: center;
  color: #fff;
  font-weight: 900;
}
.cover.blue, .course-cover-large.blue { background: linear-gradient(135deg, #156de6, #52b6ff); }
.cover.teal { background: linear-gradient(135deg, #0faeab, #5dd6c5); }
.cover.dark { background: linear-gradient(135deg, #191919, #db4b25); }
.cover.green { background: linear-gradient(135deg, #259c55, #7ad487); }
.tabbar {
  position: absolute;
  left: 0;
  right: 0;
  bottom: 0;
  height: 64px;
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  background: #fff;
  border-top: 1px solid var(--line);
}
.tabbar a {
  display: grid;
  place-items: center;
  color: #535d68;
  font-size: 13px;
}
.tabbar .on { color: var(--orange); font-weight: 800; }

.search {
  height: 42px;
  margin: 8px 16px 10px;
  display: flex;
  align-items: center;
  padding: 0 14px;
  color: #b1bac5;
  background: #fff;
  border: 1px solid var(--line);
}
.pill-tabs, .seg-tabs, .state-filter, .category-strip, .status-strip {
  display: flex;
  gap: 18px;
  overflow: hidden;
  padding: 0 16px;
  background: #fff;
}
.pill-tabs { height: 46px; align-items: center; }
.pill-tabs b { height: 46px; display: flex; align-items: center; border-bottom: 3px solid transparent; }
.pill-tabs .active { color: var(--orange); border-bottom-color: var(--orange); }
.category-strip, .state-filter, .status-strip { height: 38px; align-items: center; white-space: nowrap; color: var(--sub); }
.category-strip .on, .state-filter .on, .status-strip .on { color: var(--orange); }
.category-box {
  margin: 8px 16px 0;
  padding: 12px 0 10px;
  background: #fff;
  border: 1px solid var(--line);
}
.category-title {
  padding: 0 14px 8px;
  color: var(--muted);
  font-size: 12px;
}
.category-box .category-strip {
  height: 30px;
  padding: 0 14px;
  gap: 10px;
  background: transparent;
}
.category-box .category-strip a {
  padding: 5px 9px;
  background: #f5f7fa;
  color: var(--sub);
  font-size: 12px;
}
.category-box .category-strip .on {
  color: var(--orange);
  background: var(--orange-soft);
}
.course-grid {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 10px;
  padding-bottom: 70px;
}
.course-grid article {
  position: relative;
  min-height: 186px;
  background: #fff;
  border: 1px solid var(--line);
}
.course-grid span {
  position: absolute;
  top: 8px;
  right: 8px;
  padding: 3px 7px;
  color: #fff;
  background: rgba(0,0,0,.62);
  font-size: 11px;
}
.material-path {
  height: 44px;
  display: flex;
  align-items: center;
  padding: 0 16px;
  color: var(--muted);
}
.file-list { padding: 0 16px 70px; }
.file-list article {
  display: flex;
  align-items: center;
  gap: 12px;
  min-height: 68px;
}
.file-list div { flex: 1; min-width: 0; }
.file-list b { font-size: 15px; }
.file-list i {
  width: 28px;
  height: 28px;
  flex: 0 0 28px;
  background: var(--orange);
}
.file-list .folder { background: #ffb23e; }
.file-list .video { background: var(--purple); }
.file-list .doc { background: var(--orange); }
.file-list .audio { background: var(--teal); }

.center-head {
  height: 116px;
  padding: 28px 20px 0;
  color: #fff;
  background: linear-gradient(120deg, #ff7a2f, #f6ae35);
}
.center-head span { opacity: .8; }
.seg-tabs {
  gap: 0;
  padding: 12px 16px;
}
.seg-tabs button {
  flex: 1;
  color: var(--sub);
  background: #f3f5f8;
}
.seg-tabs button.active { color: #fff; background: var(--orange); }
.project-list { padding: 0 16px 70px; }
.project-card {
  margin-bottom: 14px;
  padding: 12px;
  background: #fff;
  border: 1px solid var(--line);
}
.project-cover {
  height: 92px;
  display: grid;
  place-items: center;
  margin: -12px -12px 12px;
  color: #fff;
  font-size: 20px;
  font-weight: 900;
}
.project-cover.orange { background: linear-gradient(135deg, #ff7a2f, #ffbf52); }
.project-cover.teal { background: linear-gradient(135deg, #0faeab, #5dd6c5); }
.project-cover.green { background: linear-gradient(135deg, #259c55, #7ad487); }
.project-card h3 { margin: 10px 0 6px; font-size: 18px; }
.project-card p { margin: 0 0 12px; color: var(--muted); }
.project-card .progress { background: #edf1f5; }
.project-card .progress i { background: var(--orange); }
.project-card button { margin-top: 12px; background: var(--orange); color: #fff; width: 100%; }

.detail-nav, .player-head {
  height: 50px;
  display: grid;
  grid-template-columns: 52px 1fr 52px;
  align-items: center;
  padding: 0 14px;
  background: #fff;
}
.detail-nav h2 { margin: 0; text-align: center; font-size: 17px; }
.project-hero, .course-detail {
  margin: 12px 16px;
  padding: 16px;
  background: #fff;
  border: 1px solid var(--line);
}
.project-hero h2, .course-detail h2 { margin: 12px 0 8px; font-size: 22px; letter-spacing: 0; }
.project-hero p, .course-detail p { color: var(--sub); line-height: 1.55; }
.project-hero .progress, .course-detail .progress { background: #edf1f5; }
.project-hero .progress i, .course-detail .progress i { background: var(--orange); }
.project-hero button, .course-detail button { width: 100%; margin-top: 14px; background: var(--orange); color: #fff; }
.meta { display: flex; gap: 10px; color: var(--muted); font-size: 12px; }
.stage-list { padding: 0 16px 20px; }
.stage-list.compact { padding-bottom: 0; }
.stage-list article {
  margin-bottom: 12px;
  padding: 14px;
  background: #fff;
  border: 1px solid var(--line);
}
.stage-list header {
  display: flex;
  justify-content: space-between;
  padding-bottom: 10px;
  border-bottom: 1px solid var(--line);
}
.stage-list header span { color: var(--muted); }
.lesson {
  min-height: 58px;
  display: flex;
  align-items: center;
  gap: 10px;
  border-bottom: 1px solid var(--line);
}
.lesson:last-child { border-bottom: 0; }
.lesson i {
  width: 30px;
  height: 30px;
  display: grid;
  place-items: center;
  color: var(--sub);
  background: #f1f4f8;
  font-style: normal;
}
.lesson div { flex: 1; min-width: 0; }
.lesson b { font-size: 14px; }
.lesson p { margin: 4px 0 0; color: var(--muted); font-size: 12px; }
.lesson.done i { color: #fff; background: var(--green); }
.lesson.active { background: #fff8f3; }
.lesson.active i { color: #fff; background: var(--orange); }
.course-cover-large {
  height: 168px;
  margin: 12px 16px 0;
  display: grid;
  place-items: center;
  color: #fff;
  font-size: 24px;
  font-weight: 900;
}

.player-phone { background: #10151d; color: #fff; }
.player-head { background: #171d27; color: #fff; }
.player-head a { color: #fff; }
.player-head b { text-align: center; font-size: 15px; }
.video-player {
  position: relative;
  height: 310px;
  display: grid;
  place-items: center;
  text-align: center;
  overflow: hidden;
  background:
    radial-gradient(circle at 42% 36%, rgba(255,122,47,.36), transparent 118px),
    linear-gradient(135deg, #1d2735, #05070a);
}
.video-player h2 { margin: 0; font-size: 22px; }
.video-player p { color: #c5ced8; }
.video-player button {
  width: 70px;
  height: 70px;
  border-radius: 50%;
  color: #fff;
  background: rgba(255,255,255,.18);
}
.watermark {
  position: absolute;
  left: 20px;
  top: 108px;
  color: rgba(255,255,255,.18);
  font-size: 18px;
  transform: rotate(-18deg);
}
.player-toolbar {
  display: flex;
  gap: 8px;
  padding: 12px;
  background: #171d27;
}
.player-toolbar button { flex: 1; color: #dfe7ef; background: #252e3b; }
.player-toolbar .primary { background: var(--orange); color: #fff; }
.playlist {
  padding: 14px 16px;
  background: #202733;
}
.playlist h3 { margin: 0 0 8px; }
.playlist .lesson { border-bottom-color: rgba(255,255,255,.08); }
.playlist .lesson b { color: #fff; }
.guard {
  margin: 14px 16px;
  padding: 12px;
  color: #ffc59e;
  background: rgba(255,122,47,.14);
  border: 1px solid rgba(255,122,47,.35);
}

.mine-head {
  display: flex;
  align-items: center;
  gap: 14px;
  padding: 26px 18px 22px;
  color: #fff;
  background: linear-gradient(120deg, #ff7a2f, #f6ae35);
}
.avatar {
  width: 62px;
  height: 62px;
  display: grid;
  place-items: center;
  border-radius: 50%;
  color: #fff;
  background: linear-gradient(135deg, #1783ff, #20c1a6);
  font-size: 24px;
  font-weight: 900;
}
.mine-head h2 { margin: 0; font-size: 24px; }
.mine-head p { margin: 5px 0 0; opacity: .85; }
.mine-stats {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 8px;
  padding: 12px 16px 4px;
}
.mine-stats a {
  padding: 14px 6px;
  text-align: center;
  background: #fff;
  color: var(--muted);
}
.mine-stats b { display: block; color: var(--ink); font-size: 18px; }
.record-list span { color: var(--orange); font-size: 12px; }
.menu-list { padding: 4px 16px 70px; }
.menu-list a {
  display: flex;
  align-items: center;
  justify-content: space-between;
  color: var(--ink);
}
.menu-list b { color: var(--muted); }