/* ============================================================
   歌之阶 · Vocal Coach  设计系统
   ============================================================ */

:root {
  /* 主色 —— 声乐/音乐主题：暖橙 + 深靛 */
  --c-primary: #e8622c;
  --c-primary-soft: #fdf1ec;
  --c-primary-dark: #c44d1d;
  --c-accent: #4c5fd7;
  --c-accent-soft: #eef0fd;
  --c-ok: #2a9d6f;
  --c-ok-soft: #e8f6f0;
  --c-warn: #e0a11b;
  --c-warn-soft: #fdf5e3;
  --c-bad: #d64545;
  --c-bad-soft: #fceded;

  --c-bg: #f7f6f3;
  --c-surface: #ffffff;
  --c-surface-2: #fbfaf8;
  --c-border: #e6e2da;
  --c-border-strong: #d5d0c6;

  --t-primary: #23201b;
  --t-secondary: #5d574c;
  --t-muted: #918a7d;
  --t-invert: #ffffff;

  --r-sm: 8px;
  --r-md: 12px;
  --r-lg: 18px;
  --r-xl: 26px;
  --r-full: 999px;

  --sh-sm: 0 1px 2px rgba(35, 32, 27, .06);
  --sh-md: 0 4px 14px rgba(35, 32, 27, .07);
  --sh-lg: 0 12px 36px rgba(35, 32, 27, .10);

  --sidebar-w: 236px;
  --header-h: 62px;
}

* { box-sizing: border-box; }

html, body {
  margin: 0;
  padding: 0;
  height: 100%;
}

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

button, input, select, textarea { font-family: inherit; font-size: inherit; color: inherit; }
button { cursor: pointer; border: none; background: none; }
a { color: var(--c-accent); text-decoration: none; }
h1, h2, h3, h4 { margin: 0; font-weight: 700; line-height: 1.3; }
p { margin: 0 0 1em; }
ul, ol { margin: 0 0 1em; padding-left: 1.4em; }

/* ---------- 布局 ---------- */
.app { display: flex; height: 100vh; overflow: hidden; }

/* 侧边栏 */
.sidebar {
  width: var(--sidebar-w);
  flex: 0 0 var(--sidebar-w);
  background: var(--c-surface);
  border-right: 1px solid var(--c-border);
  display: flex;
  flex-direction: column;
  z-index: 30;
}

.brand {
  height: var(--header-h);
  display: flex;
  align-items: center;
  gap: 10px;
  padding: 0 18px;
  border-bottom: 1px solid var(--c-border);
  flex-shrink: 0;
}
.brand-logo {
  width: 32px; height: 32px;
  border-radius: 10px;
  background: linear-gradient(140deg, var(--c-primary), #f0932b);
  display: grid; place-items: center;
  color: #fff; font-size: 17px; flex-shrink: 0;
  box-shadow: 0 3px 8px rgba(232, 98, 44, .3);
}
.brand-text b { display: block; font-size: 15px; letter-spacing: .5px; }
.brand-text span { display: block; font-size: 10px; color: var(--t-muted); letter-spacing: 1.4px; text-transform: uppercase; }

.nav { flex: 1; overflow-y: auto; padding: 12px 10px 20px; }
.nav-group-label {
  font-size: 11px; color: var(--t-muted); font-weight: 700;
  padding: 14px 10px 6px; letter-spacing: 1px;
}
.nav-item {
  display: flex; align-items: center; gap: 11px;
  width: 100%; padding: 9px 11px; margin-bottom: 2px;
  border-radius: var(--r-md);
  color: var(--t-secondary); font-size: 14px; font-weight: 500;
  transition: background .15s, color .15s;
  text-align: left;
}
.nav-item:hover { background: var(--c-surface-2); color: var(--t-primary); }
.nav-item.active { background: var(--c-primary-soft); color: var(--c-primary-dark); font-weight: 700; }
.nav-item .ico { width: 20px; text-align: center; font-size: 16px; flex-shrink: 0; }
.nav-item .badge {
  margin-left: auto; font-size: 10px; font-weight: 700;
  background: var(--c-primary); color: #fff;
  padding: 1px 6px; border-radius: var(--r-full);
}

.sidebar-foot {
  padding: 12px 14px; border-top: 1px solid var(--c-border);
  font-size: 12px; color: var(--t-muted); flex-shrink: 0;
}
.mic-status { display: flex; align-items: center; gap: 7px; }
.mic-dot {
  width: 8px; height: 8px; border-radius: 50%;
  background: var(--t-muted); flex-shrink: 0;
}
.mic-dot.on { background: var(--c-ok); box-shadow: 0 0 0 3px var(--c-ok-soft); }
.mic-dot.err { background: var(--c-bad); box-shadow: 0 0 0 3px var(--c-bad-soft); }

/* 主区 */
.main { flex: 1; display: flex; flex-direction: column; min-width: 0; }

.header {
  height: var(--header-h);
  flex-shrink: 0;
  background: rgba(255, 255, 255, .82);
  backdrop-filter: blur(12px);
  border-bottom: 1px solid var(--c-border);
  display: flex; align-items: center; gap: 14px;
  padding: 0 24px;
  z-index: 20;
}
.header h1 { font-size: 17px; }
.header .sub { font-size: 12.5px; color: var(--t-muted); font-weight: 400; }
.header-right { margin-left: auto; display: flex; align-items: center; gap: 10px; }

.content { flex: 1; overflow-y: auto; padding: 24px 28px 80px; }
.content-inner { max-width: 1080px; margin: 0 auto; }
.content-inner.wide { max-width: 1320px; }

.menu-toggle {
  display: none; font-size: 20px; line-height: 1;
  padding: 0; width: 44px; height: 44px; flex-shrink: 0;
  align-items: center; justify-content: center;
  border-radius: var(--r-md); color: var(--t-secondary);
}
.menu-toggle:active { background: var(--c-surface-2); }

/* ---------- 通用组件 ---------- */
.card {
  background: var(--c-surface);
  border: 1px solid var(--c-border);
  border-radius: var(--r-lg);
  box-shadow: var(--sh-sm);
}
.card-pad { padding: 22px 24px; }
.card-head {
  padding: 16px 22px; border-bottom: 1px solid var(--c-border);
  display: flex; align-items: center; gap: 12px;
}
.card-head h3 { font-size: 15.5px; }
.card-head .spacer { margin-left: auto; }

.btn {
  display: inline-flex; align-items: center; justify-content: center; gap: 7px;
  padding: 9px 18px; border-radius: var(--r-md);
  font-size: 14px; font-weight: 600;
  background: var(--c-primary); color: #fff;
  transition: transform .1s, box-shadow .15s, background .15s;
  box-shadow: 0 2px 6px rgba(232, 98, 44, .28);
  white-space: nowrap;
}
.btn:hover { background: var(--c-primary-dark); }
.btn:active { transform: translateY(1px); }
.btn:disabled { opacity: .45; cursor: not-allowed; transform: none; box-shadow: none; }
.btn.ghost { background: transparent; color: var(--t-secondary); border: 1px solid var(--c-border-strong); box-shadow: none; }
.btn.ghost:hover { background: var(--c-surface-2); color: var(--t-primary); }
.btn.soft { background: var(--c-primary-soft); color: var(--c-primary-dark); box-shadow: none; }
.btn.soft:hover { background: #fbe3d9; }
.btn.accent { background: var(--c-accent); box-shadow: 0 2px 6px rgba(76, 95, 215, .28); }
.btn.accent:hover { background: #3c4dbd; }
.btn.ok { background: var(--c-ok); box-shadow: 0 2px 6px rgba(42, 157, 111, .28); }
.btn.ok:hover { background: #23875e; }
.btn.lg { padding: 12px 26px; font-size: 15px; border-radius: var(--r-md); }
.btn.sm { padding: 6px 12px; font-size: 12.5px; }
.btn.block { width: 100%; }

.tag {
  display: inline-block; padding: 2px 9px; border-radius: var(--r-full);
  font-size: 11.5px; font-weight: 700; letter-spacing: .3px;
  background: var(--c-surface-2); color: var(--t-secondary);
  border: 1px solid var(--c-border);
}
.tag.p { background: var(--c-primary-soft); color: var(--c-primary-dark); border-color: #f7d9cb; }
.tag.a { background: var(--c-accent-soft); color: var(--c-accent); border-color: #d9defa; }
.tag.ok { background: var(--c-ok-soft); color: var(--c-ok); border-color: #c5e8d9; }
.tag.warn { background: var(--c-warn-soft); color: #a8760a; border-color: #f5e3b8; }
.tag.bad { background: var(--c-bad-soft); color: var(--c-bad); border-color: #f6cfcf; }

.grid { display: grid; gap: 18px; }
.g2 { grid-template-columns: repeat(2, minmax(0, 1fr)); }
.g3 { grid-template-columns: repeat(3, minmax(0, 1fr)); }
.g4 { grid-template-columns: repeat(4, minmax(0, 1fr)); }
/* minmax(0,1fr) 而非 1fr：1fr 的 auto 最小值会被超长内容撑开，导致移动端溢出 */
.g-side { grid-template-columns: minmax(0, 1fr) 320px; }
.g-side-l { grid-template-columns: 300px minmax(0, 1fr); }

.section-title {
  display: flex; align-items: center; gap: 10px;
  margin: 30px 0 16px; font-size: 16px; font-weight: 700;
}
.section-title::before {
  content: ''; width: 4px; height: 17px; border-radius: 2px;
  background: var(--c-primary);
}
.section-title:first-child { margin-top: 0; }
.section-title .spacer { margin-left: auto; }
.muted { color: var(--t-muted); }
.small { font-size: 12.5px; }
.tiny { font-size: 11.5px; }
.center { text-align: center; }
.mono { font-family: "SF Mono", "Cascadia Mono", Consolas, monospace; }

.row { display: flex; align-items: center; gap: 10px; }
.row.wrap { flex-wrap: wrap; }
.spacer { margin-left: auto; }

.divider { height: 1px; background: var(--c-border); margin: 22px 0; }

/* 首页 */
.hero {
  background: linear-gradient(135deg, #23201b 0%, #3a2f26 55%, #5a3a24 100%);
  color: #fff; border-radius: var(--r-xl);
  padding: 34px 36px; margin-bottom: 26px;
  position: relative; overflow: hidden;
}
.hero::after {
  content: ''; position: absolute; right: -50px; top: -70px;
  width: 280px; height: 280px; border-radius: 50%;
  background: radial-gradient(circle, rgba(232, 98, 44, .45), transparent 68%);
}
.hero h2 { font-size: 26px; margin-bottom: 8px; letter-spacing: .5px; }
.hero p { color: #d9cfc2; margin-bottom: 20px; max-width: 560px; font-size: 14.5px; }
.hero-actions { display: flex; gap: 11px; flex-wrap: wrap; }
.hero .btn.ghost { border-color: rgba(255, 255, 255, .32); color: #fff; }
.hero .btn.ghost:hover { background: rgba(255, 255, 255, .12); color: #fff; }
.hero-stats { display: flex; gap: 30px; margin-top: 26px; position: relative; }
.hero-stat b { display: block; font-size: 23px; line-height: 1.2; }
.hero-stat span { font-size: 12px; color: #b8ada0; }

.tile {
  background: var(--c-surface); border: 1px solid var(--c-border);
  border-radius: var(--r-lg); padding: 20px;
  cursor: pointer; transition: all .18s;
  display: flex; flex-direction: column;
}
.tile:hover { transform: translateY(-3px); box-shadow: var(--sh-md); border-color: var(--c-border-strong); }
.tile-ico {
  width: 42px; height: 42px; border-radius: 12px;
  display: grid; place-items: center; font-size: 21px;
  background: var(--c-primary-soft); margin-bottom: 13px;
}
.tile h4 { font-size: 15px; margin-bottom: 5px; }
.tile p { font-size: 12.8px; color: var(--t-muted); margin: 0; line-height: 1.55; }
.tile .tile-meta { margin-top: 12px; font-size: 11.5px; color: var(--t-muted); display: flex; gap: 8px; align-items: center; }

/* 进度条 */
.bar { height: 7px; background: var(--c-surface-2); border-radius: 4px; overflow: hidden; border: 1px solid var(--c-border); }
.bar-fill { height: 100%; background: linear-gradient(90deg, var(--c-primary), #f0932b); border-radius: 4px; transition: width .4s; }
.bar-fill.ok { background: linear-gradient(90deg, var(--c-ok), #52c98d); }
.bar-fill.a { background: linear-gradient(90deg, var(--c-accent), #7b8af0); }
.bar-fill.w { background: linear-gradient(90deg, var(--c-warn), #f2c14e); }

/* 教程图文 */
.article { max-width: 760px; font-size: 15.5px; line-height: 1.85; }

/* ---------- 图文教程：移动端详情整页化 ----------
   ≤1280px 时 .g-side 折叠为单列，列表会堆叠在正文上方，
   点开教程后正文被压在长列表下方，用户以为是没反应。
   开启 lesson-detail-mode 时隐藏列表，让正文成为独立的一页。 */
.lesson-back { margin-bottom: 4px; }
.no-desktop { display: none; }
@media (max-width: 1280px) {
  .no-desktop { display: inline-flex; }
  .lesson-detail-mode #lesson-list { display: none; }
  /* 整页详情时正文占满宽度，不再受右栏宽度限制 */
  .lesson-detail-mode .toc { position: static; }
  .lesson-detail-mode .article { max-width: 100%; }
  .lesson-detail-mode .content-inner { max-width: 760px; }
  /* 分类栏是 .lesson-detail-mode 的兄弟节点，需用 is-hidden-mobile 标记 */
  .is-hidden-mobile { display: none !important; }
}
.article h2 { font-size: 21px; margin: 30px 0 12px; padding-bottom: 8px; border-bottom: 2px solid var(--c-primary-soft); }
.article h3 { font-size: 17px; margin: 24px 0 10px; color: var(--c-primary-dark); }
.article ul li, .article ol li { margin-bottom: 7px; }
.article strong { color: var(--c-primary-dark); }
.article code {
  background: var(--c-surface-2); border: 1px solid var(--c-border);
  padding: 1px 6px; border-radius: 5px; font-size: 13px;
  font-family: "SF Mono", Consolas, monospace;
}
.figure {
  margin: 22px 0; padding: 18px; background: var(--c-surface-2);
  border: 1px solid var(--c-border); border-radius: var(--r-lg);
}
.figure svg { display: block; width: 100%; height: auto; }
.figure figcaption { margin-top: 12px; font-size: 12.8px; color: var(--t-muted); text-align: center; }

/* 图解内容在窄屏可横向滚动查看，避免文字被压得无法辨认 */
.figure-scroll { overflow-x: auto; -webkit-overflow-scrolling: touch; }
.callout {
  padding: 14px 18px; border-radius: var(--r-md);
  border-left: 4px solid var(--c-primary);
  background: var(--c-primary-soft); margin: 18px 0; font-size: 14.5px;
}
.callout.tip { border-color: var(--c-accent); background: var(--c-accent-soft); }
.callout.warn { border-color: var(--c-warn); background: var(--c-warn-soft); }
.callout b { display: block; margin-bottom: 4px; }

/* 目录 */
.toc { position: sticky; top: 0; }
.toc a {
  display: block; padding: 6px 12px; border-radius: var(--r-sm);
  font-size: 13.5px; color: var(--t-secondary); border-left: 2px solid transparent;
}
.toc a:hover { background: var(--c-surface-2); color: var(--c-primary-dark); }
.toc a.active { color: var(--c-primary-dark); font-weight: 700; border-left-color: var(--c-primary); background: var(--c-primary-soft); }

/* 列表项（课程/歌曲） */
.list-item {
  display: flex; align-items: center; gap: 15px;
  padding: 14px 18px; border-bottom: 1px solid var(--c-border);
  cursor: pointer; transition: background .15s;
  /* 防止超长内容撑破容器 */
  min-width: 0; max-width: 100%;
}
.list-item:last-child { border-bottom: none; }
.list-item:hover { background: var(--c-surface-2); }
.list-item.active { background: var(--c-primary-soft); }
.li-ico {
  width: 44px; height: 44px; border-radius: var(--r-md);
  display: grid; place-items: center; font-size: 19px; flex-shrink: 0;
  background: var(--c-surface-2); border: 1px solid var(--c-border);
}
.li-main { flex: 1; min-width: 0; overflow: hidden; }
.li-main b {
  display: block; font-size: 14.5px; margin-bottom: 2px;
  overflow: hidden; text-overflow: ellipsis; white-space: nowrap;
}
.li-main span {
  font-size: 12.5px; color: var(--t-muted);
  overflow: hidden; text-overflow: ellipsis;
  display: -webkit-box; -webkit-line-clamp: 2; -webkit-box-orient: vertical;
}
.li-right { display: flex; align-items: center; gap: 10px; flex-shrink: 0; }

/* 音高检测可视化 */
.pitch-stage {
  background: var(--c-surface); border: 1px solid var(--c-border);
  border-radius: var(--r-lg); padding: 20px 22px; text-align: center;
}
.pitch-note {
  font-size: 62px; font-weight: 800; line-height: 1; letter-spacing: 1px;
  font-family: "SF Mono", Consolas, monospace;
  color: var(--c-primary); min-height: 66px;
  transition: color .15s;
}
.pitch-note.ok { color: var(--c-ok); }
.pitch-note.bad { color: var(--c-bad); }
.pitch-cents { font-size: 15px; font-weight: 700; min-height: 22px; font-family: "SF Mono", Consolas, monospace; }
.pitch-freq { font-size: 12.5px; color: var(--t-muted); font-family: "SF Mono", Consolas, monospace; }

.meter { height: 10px; background: var(--c-surface-2); border-radius: 5px; overflow: hidden; border: 1px solid var(--c-border); }
.meter-fill { height: 100%; width: 0; background: linear-gradient(90deg, var(--c-ok), var(--c-warn) 75%, var(--c-bad)); transition: width .06s; }

canvas.viz { width: 100%; display: block; border-radius: var(--r-md); background: var(--c-surface-2); border: 1px solid var(--c-border); }

/* 测试题 */
.quiz-opt {
  display: flex; align-items: center; gap: 12px;
  padding: 13px 18px; border: 1.5px solid var(--c-border);
  border-radius: var(--r-md); margin-bottom: 10px;
  cursor: pointer; transition: all .15s; background: var(--c-surface);
  font-size: 14.5px; font-weight: 500; width: 100%; text-align: left;
}
.quiz-opt:hover:not(.done) { border-color: var(--c-primary); background: var(--c-primary-soft); }
.quiz-opt .k {
  width: 26px; height: 26px; border-radius: 7px; flex-shrink: 0;
  background: var(--c-surface-2); border: 1px solid var(--c-border);
  display: grid; place-items: center; font-size: 12.5px; font-weight: 700;
}
.quiz-opt.sel { border-color: var(--c-primary); background: var(--c-primary-soft); }
.quiz-opt.sel .k { background: var(--c-primary); color: #fff; border-color: var(--c-primary); }
.quiz-opt.right { border-color: var(--c-ok); background: var(--c-ok-soft); }
.quiz-opt.right .k { background: var(--c-ok); color: #fff; border-color: var(--c-ok); }
.quiz-opt.wrong { border-color: var(--c-bad); background: var(--c-bad-soft); }
.quiz-opt.wrong .k { background: var(--c-bad); color: #fff; border-color: var(--c-bad); }
.quiz-opt.done { cursor: default; }

/* 评分环 */
.ring { position: relative; width: 168px; height: 168px; flex-shrink: 0; }
.ring svg { transform: rotate(-90deg); }
.ring-txt {
  position: absolute; inset: 0; display: grid; place-content: center; text-align: center;
}
.ring-txt b { font-size: 42px; line-height: 1; }
.ring-txt span { font-size: 12.5px; color: var(--t-muted); }

/* 统计块 */
.stat { padding: 15px 17px; background: var(--c-surface-2); border: 1px solid var(--c-border); border-radius: var(--r-md); }
.stat b { display: block; font-size: 23px; line-height: 1.25; }
.stat span { font-size: 12px; color: var(--t-muted); }

/* 提示/弹层 */
.toast-wrap { position: fixed; top: 18px; right: 18px; z-index: 200; display: flex; flex-direction: column; gap: 9px; }
.toast {
  padding: 11px 18px; border-radius: var(--r-md); font-size: 13.5px; font-weight: 600;
  background: var(--t-primary); color: #fff; box-shadow: var(--sh-lg);
  animation: toastIn .22s ease; max-width: 340px;
}
.toast.ok { background: var(--c-ok); }
.toast.bad { background: var(--c-bad); }
.toast.warn { background: var(--c-warn); }
@keyframes toastIn { from { opacity: 0; transform: translateX(24px); } }

.modal-mask {
  position: fixed; inset: 0; background: rgba(35, 32, 27, .48);
  display: grid; place-items: center; z-index: 300; padding: 24px;
  animation: fade .18s;
}
@keyframes fade { from { opacity: 0; } }
.modal {
  background: var(--c-surface); border-radius: var(--r-xl);
  max-width: 620px; width: 100%; max-height: 86vh; overflow-y: auto;
  box-shadow: var(--sh-lg);
}
.modal-head { padding: 20px 26px; border-bottom: 1px solid var(--c-border); display: flex; align-items: center; }
.modal-body { padding: 22px 26px; }
.modal-foot { padding: 16px 26px; border-top: 1px solid var(--c-border); display: flex; gap: 10px; justify-content: flex-end; }

/* 视频 */
.video-wrap { position: relative; background: #000; border-radius: var(--r-lg); overflow: hidden; aspect-ratio: 16/9; }
.video-wrap video { width: 100%; height: 100%; display: block; object-fit: contain; background: #000; }
.video-ph {
  position: absolute; inset: 0; display: grid; place-items: center;
  background: linear-gradient(140deg, #2b2620, #4a382a); color: #d8cec2; text-align: center; padding: 24px;
}
.video-ph .big { font-size: 52px; margin-bottom: 12px; opacity: .6; }
.drop-zone {
  border: 2px dashed rgba(255, 255, 255, .3); border-radius: var(--r-lg);
  padding: 30px 20px; text-align: center; cursor: pointer; transition: all .18s;
}
.drop-zone:hover, .drop-zone.over { border-color: var(--c-primary); background: rgba(232, 98, 44, .12); }

/* 歌词/旋律 */
.lyric-line {
  padding: 8px 14px; border-radius: var(--r-sm); margin-bottom: 3px;
  font-size: 17px; transition: all .2s; display: flex; align-items: center; gap: 10px;
}
.lyric-line .pinyin { font-size: 12px; color: var(--t-muted); }
.lyric-line.cur { background: var(--c-primary-soft); color: var(--c-primary-dark); font-weight: 700; }
.lyric-line.sung { color: var(--t-muted); }

/* 键盘 */
.keys { display: flex; gap: 3px; justify-content: center; margin: 10px 0; }
.key {
  width: 30px; border-radius: 0 0 6px 6px; background: var(--c-surface);
  border: 1px solid var(--c-border-strong); border-top: none;
  height: 92px; position: relative; cursor: pointer;
  display: flex; align-items: flex-end; justify-content: center;
  padding-bottom: 6px; font-size: 10px; color: var(--t-muted);
  transition: background .1s;
}
.key:active, .key.hit { background: var(--c-primary-soft); border-color: var(--c-primary); }
.key.black { background: #2b2620; border-color: #2b2620; height: 60px; width: 19px; z-index: 2; color: #a89c8e; margin: 0 -10px; }
.key.hit.black { background: var(--c-primary); }

/* 计时/节奏 */
.beat-dot {
  width: 15px; height: 15px; border-radius: 50%;
  background: var(--c-border-strong); transition: all .08s;
}
.beat-dot.hit { background: var(--c-primary); transform: scale(1.35); }
.beat-dot.cur { background: var(--c-accent); box-shadow: 0 0 0 4px var(--c-accent-soft); }

/* 练习计时器 */
.timer-big { font-size: 54px; font-weight: 800; font-family: "SF Mono", Consolas, monospace; letter-spacing: 2px; line-height: 1.1; }
.breath-orb {
  width: 150px; height: 150px; border-radius: 50%;
  background: radial-gradient(circle at 35% 32%, #ffd9a0, var(--c-primary));
  margin: 0 auto; transition: transform 1s ease, box-shadow 1s;
  box-shadow: 0 0 0 0 rgba(232, 98, 44, .35);
}

.breath-bar {
  width: 100%; max-width: 320px; height: 8px; margin: 0 auto;
  background: var(--c-surface-2); border-radius: 99px; overflow: hidden;
}
.breath-bar-fill { height: 100%; width: 0; border-radius: 99px; transition: width .1s linear; }

/* 徽章 */
.badge-ico {
  width: 46px; height: 46px; border-radius: 50%;
  display: grid; place-items: center; font-size: 22px; flex-shrink: 0;
  background: var(--c-surface-2); border: 1px solid var(--c-border);
}
.badge-ico.gold { background: linear-gradient(140deg, #ffe9a8, #f5b942); border-color: #e8a52a; }
.badge-ico.silver { background: linear-gradient(140deg, #f0f2f5, #c3cad4); border-color: #a8b2c0; }
.badge-ico.bronze { background: linear-gradient(140deg, #f5d5bd, #cf8f5e); border-color: #b87a48; }

.empty { text-align: center; padding: 60px 20px; color: var(--t-muted); }
.empty .ico { font-size: 46px; margin-bottom: 14px; opacity: .45; }

.chip-row { display: flex; gap: 7px; flex-wrap: wrap; }
.chip {
  padding: 6px 13px; border-radius: var(--r-full); font-size: 12.5px; font-weight: 600;
  background: var(--c-surface); border: 1px solid var(--c-border); color: var(--t-secondary);
  transition: all .15s; white-space: nowrap;
}
.chip:hover { border-color: var(--c-border-strong); }
.chip.on { background: var(--c-primary); color: #fff; border-color: var(--c-primary); }

/* 表格 */
table.tbl { width: 100%; border-collapse: collapse; font-size: 13.5px; }
table.tbl th, table.tbl td { padding: 9px 12px; text-align: left; border-bottom: 1px solid var(--c-border); }
table.tbl th { font-size: 12px; color: var(--t-muted); font-weight: 700; background: var(--c-surface-2); }
table.tbl tr:last-child td { border-bottom: none; }

/* 移动端：宽表格横向滚动，保证列内容不被挤压 */
.table-scroll {
  overflow-x: auto; -webkit-overflow-scrolling: touch;
  margin: 0 -14px; padding: 0 14px;
}
.table-scroll table.tbl { min-width: 460px; }

/* 呼吸/共鸣图示 SVG 通用 */
.svg-lbl { font-family: "PingFang SC", "Microsoft YaHei", sans-serif; }

/* ============================================================
   响应式适配
   断点策略：
     ≤1280px  小笔记本 / 平板横屏
     ≤1024px  平板竖屏
     ≤768px   大手机
     ≤560px   普通手机（主力移动端）
     ≤380px   小屏手机
   ============================================================ */

/* ---------- 大屏与桌面 ---------- */
@media (max-width: 1280px) {
  .content { padding: 22px 22px 80px; }
  .content-inner { max-width: 1000px; }
  .g4 { grid-template-columns: repeat(2, minmax(0, 1fr)); }
  .g-side, .g-side-l { grid-template-columns: minmax(0, 1fr); }
}

/* ---------- 平板 ---------- */
@media (max-width: 1024px) {
  :root { --sidebar-w: 210px; }
  .content { padding: 20px 20px 76px; }
  .header { padding: 0 20px; }
  .g3 { grid-template-columns: repeat(2, minmax(0, 1fr)); }
  /* 侧边栏在平板转为抽屉式 */
  .sidebar {
    position: fixed; left: 0; top: 0; bottom: 0; z-index: 30;
    transform: translateX(-100%); transition: transform .28s cubic-bezier(.4, 0, .2, 1);
    box-shadow: var(--sh-lg);
  }
  .sidebar.open { transform: none; }
  .menu-toggle { display: flex; }
  .sidebar-mask {
    position: fixed; inset: 0; background: rgba(35, 32, 27, .45);
    z-index: 29; animation: fade .2s; backdrop-filter: blur(2px);
  }
}

/* ---------- 手机主力断点 ---------- */
@media (max-width: 768px) {
  :root {
    --header-h: 56px;
    --r-lg: 14px;
    --r-xl: 18px;
  }
  body { font-size: 15px; }

  /* 触摸目标不小于 44×44（Apple HIG 标准） */
  .btn { padding: 11px 18px; min-height: 44px; }
  .btn.sm { padding: 8px 13px; min-height: 38px; }
  .btn.lg { padding: 14px 24px; min-height: 52px; font-size: 15.5px; }
  .btn.block { width: 100%; }

  .chip { padding: 9px 15px; min-height: 38px; display: inline-flex; align-items: center; }
  .nav-item { padding: 12px 12px; min-height: 46px; }
  .quiz-opt { padding: 15px 16px; min-height: 54px; }
  .list-item { padding: 14px 14px; }
  .key { height: 104px; width: 34px; }
  .key.black { height: 68px; width: 21px; margin: 0 -11px; }

  /* iOS 输入框聚焦自动放大：字号必须 ≥16px */
  input, select, textarea { font-size: 16px !important; }

  .g2, .g3, .g4 { grid-template-columns: minmax(0, 1fr); }
  .grid { gap: 14px; }

  /* 全局溢出防护：杜绝任何意外的水平滚动 */
  html, body { overflow-x: hidden; max-width: 100%; }
  .app { max-width: 100vw; overflow-x: hidden; }
  .content, .content-inner { max-width: 100%; overflow-x: hidden; }
  /* 长英文/URL 强制断行 */
  .content, .content-inner, .card, .article { overflow-wrap: break-word; }

  .content { padding: 16px 14px 96px; }
  .content-inner { max-width: 100%; }
  .header { padding: 0 12px; gap: 10px; }
  .header h1 { font-size: 15.5px; }
  .header .sub { font-size: 11.5px; }
  #btn-help { padding: 8px 11px; min-height: 38px; }

  .card-pad { padding: 18px 16px; }
  .card-head { padding: 14px 16px; }
  .divider { margin: 18px 0; }
  .section-title { margin: 24px 0 13px; font-size: 15px; }
  .section-title::before { height: 15px; }

  /* 首页 */
  .hero { padding: 24px 20px; border-radius: var(--r-lg); margin-bottom: 18px; }
  .hero h2 { font-size: 19.5px; margin-bottom: 6px; }
  .hero p { font-size: 13.5px; margin-bottom: 16px; max-width: 100%; }
  /* 防止中文长句撑破容器 */
  .hero h2, .hero p, .hero-actions { overflow-wrap: break-word; word-break: normal; }
  .hero-actions { gap: 8px; }
  .hero-actions .btn { flex: 1 1 auto; min-width: 130px; }
  .hero-stats {
    display: grid; grid-template-columns: repeat(4, minmax(0, 1fr));
    gap: 8px; margin-top: 20px;
  }
  .hero-stat { text-align: center; }
  .hero-stat b { font-size: 17px; display: block; }
  .hero-stat span { font-size: 10px; line-height: 1.3; display: block; }
  .tile { padding: 16px; }
  .tile-ico { width: 38px; height: 38px; font-size: 19px; margin-bottom: 10px; }

  /* 实时音高显示 */
  .pitch-stage { padding: 16px 14px; }
  .pitch-note { font-size: 44px; min-height: 48px; }
  .pitch-cents { font-size: 14px; }
  .canvas.viz { height: 120px; }
  #pm-canvas { height: 120px !important; }

  /* 评分环 */
  .ring { width: 140px; height: 140px; }
  .ring svg { width: 140px; height: 140px; }
  .ring-txt b { font-size: 34px; }

  /* 统计块 */
  .stat { padding: 12px 13px; }
  .stat b { font-size: 19px; }
  .stat span { font-size: 11px; }
  /* 仅"我的数据"统计区在手机保持两列（用专用类区分，避免误伤功能卡片网格） */
  .grid-stat-mobile { grid-template-columns: repeat(2, minmax(0, 1fr)) !important; }

  /* 弹层：移动端接近全屏 */
  .modal-mask { padding: 0; align-items: flex-end; }
  .modal {
    max-width: 100%; width: 100%; max-height: 92vh;
    border-radius: var(--r-xl) var(--r-xl) 0 0;
    animation: sheetUp .28s cubic-bezier(.4, 0, .2, 1);
  }
  .modal-head { padding: 18px 18px 14px; }
  .modal-body { padding: 18px; }
  .modal-foot { padding: 14px 18px calc(14px + env(safe-area-inset-bottom)); }
  .modal-foot .btn { flex: 1; }

  /* 提示条 */
  .toast-wrap {
    top: auto; bottom: calc(16px + env(safe-area-inset-bottom));
    right: 12px; left: 12px; align-items: center;
  }
  .toast { max-width: 100%; width: 100%; text-align: center; animation: toastUp .24s ease; }

  /* 教程正文 */
  .article { font-size: 15px; line-height: 1.8; }
  .article h2 { font-size: 18.5px; margin: 24px 0 10px; }
  .article h3 { font-size: 16px; }
  .figure { padding: 12px; margin: 16px 0; }
  .figure figcaption { font-size: 12px; }
  .callout { padding: 13px 15px; font-size: 14px; }
  table.tbl { font-size: 12.5px; }
  table.tbl th, table.tbl td { padding: 8px 9px; }
  /* 表格可横向滚动，避免挤压 */
  .table-scroll {
    overflow-x: auto; -webkit-overflow-scrolling: touch;
    margin: 0 -16px; padding: 0 16px;
    /* 右侧渐隐，暗示可滑动 */
    -webkit-mask-image: linear-gradient(to right, #000 88%, transparent 100%);
    mask-image: linear-gradient(to right, #000 88%, transparent 100%);
  }
  .table-scroll table.tbl { min-width: 440px; }

  /* 视频 */
  .video-wrap { border-radius: var(--r-md); }

  /* 呼吸训练球 */
  .breath-orb { width: 128px; height: 128px; }
  .timer-big { font-size: 42px; }

  /* 歌词 */
  .lyric-line { font-size: 16px; padding: 9px 12px; }

  /* 曲目控制：升降调按钮横向滚动 */
  .row.wrap .chip-row { overflow-x: auto; flex-wrap: nowrap; padding-bottom: 4px; -webkit-overflow-scrolling: touch; }
}

/* ---------- 普通手机 ---------- */
@media (max-width: 560px) {
  .content { padding: 14px 12px 92px; }
  .header .sub { display: none; }
  .hero { padding: 20px 17px; }
  .hero h2 { font-size: 18px; }
  .hero-actions .btn { min-width: 100%; }
  .card-pad { padding: 16px 14px; }
  .pitch-note { font-size: 38px; min-height: 42px; }
  .pitch-cents { font-size: 13px; }
  .grid { gap: 12px; }
  .g2, .g3, .g4 { gap: 12px; }
  .figure { padding: 10px; margin: 14px 0; }
  /* 图解放大到可读尺寸，可横向滑动查看全图 */
  .figure-scroll { overflow-x: auto; -webkit-overflow-scrolling: touch; margin: 0 -10px; padding: 0 10px; }
  .figure-scroll svg { min-width: 520px; }
  .figure figcaption { font-size: 12px; }
  .modal-body { padding: 16px 14px; }
  /* 表格在窄屏更紧凑 */
  table.tbl th, table.tbl td { padding: 7px 7px; font-size: 12px; }
}

/* ---------- 小屏手机 ---------- */
@media (max-width: 380px) {
  .pitch-note { font-size: 34px; }
  .hero h2 { font-size: 17px; }
  .hero-stat b { font-size: 16px; }
  .stat b { font-size: 17px; }
  .key { width: 28px; }
  .key.black { width: 18px; margin: 0 -9px; }
  .content { padding: 12px 10px 88px; }
}

/* ---------- 横屏手机（矮屏幕） ---------- */
@media (max-height: 480px) and (orientation: landscape) {
  .header { height: 48px; }
  .hero { padding: 18px; }
  .hero-stats { margin-top: 14px; }
  .modal { max-height: 96vh; }
  .breath-orb { width: 100px; height: 100px; }
  .timer-big { font-size: 34px; }
}

/* ---------- 动画 ---------- */
@keyframes sheetUp {
  from { transform: translateY(100%); }
  to { transform: translateY(0); }
}
@keyframes toastUp {
  from { opacity: 0; transform: translateY(16px); }
  to { opacity: 1; transform: translateY(0); }
}

/* ---------- 触摸设备：移除 hover 效果，避免"粘滞hover" ---------- */
@media (hover: none) and (pointer: coarse) {
  .tile:hover, .list-item:hover, .quiz-opt:hover, .chip:hover, .nav-item:hover {
    transform: none;
    background: inherit;
  }
  .tile:hover { box-shadow: var(--sh-sm); }
  .list-item:hover { background: inherit; }
  .chip:hover { border-color: var(--c-border); }
  /* 触摸时给明确的按下反馈 */
  .btn:active, .chip:active, .quiz-opt:active {
    transform: scale(.97);
    opacity: .85;
  }
  .list-item:active, .nav-item:active, .tile:active {
    background: var(--c-primary-soft);
  }
  .nav-item:active { background: var(--c-primary-soft); }
}

/* ---------- 尊重系统的"减少动效"偏好 ---------- */
@media (prefers-reduced-motion: reduce) {
  *, *::before, *::after {
    animation-duration: .01ms !important;
    animation-iteration-count: 1 !important;
    transition-duration: .01ms !important;
    scroll-behavior: auto !important;
  }
}

/* ---------- 刘海屏安全区 ---------- */
@supports (padding: max(0px)) {
  .header {
    padding-left: max(12px, env(safe-area-inset-left));
    padding-right: max(12px, env(safe-area-inset-right));
  }
  .content {
    padding-left: max(12px, env(safe-area-inset-left));
    padding-right: max(12px, env(safe-area-inset-right));
    padding-bottom: calc(80px + env(safe-area-inset-bottom));
  }
  .sidebar {
    padding-bottom: env(safe-area-inset-bottom);
  }
  .sidebar-foot { padding-bottom: calc(12px + env(safe-area-inset-bottom)); }
}

/* 桌面端滚动条 */
::-webkit-scrollbar { width: 9px; height: 9px; }
::-webkit-scrollbar-track { background: transparent; }
::-webkit-scrollbar-thumb { background: var(--c-border-strong); border-radius: 5px; }
::-webkit-scrollbar-thumb:hover { background: var(--t-muted); }

/* 移动端隐藏滚动条但保留滚动能力 */
@media (hover: none) {
  ::-webkit-scrollbar { width: 0; height: 0; }
  body { scrollbar-width: none; }
}