/* ==========================================================================
   河北音韵科技有限公司官网 · 样式表
   气质：纸与墨。以五线谱的横向线条作为视觉母题，克制、留白、少装饰。
   ========================================================================== */

/* ---------- 变量 ---------- */
:root {
  --paper: #FAF8F3;
  --paper-2: #F4F0E7;
  --paper-3: #EDE7DA;
  --ink: #17140F;
  --ink-2: #4B4438;
  --ink-3: #8A8172;
  --line: #E2DACB;
  --line-strong: #CABFA9;
  --accent: #A63D22;
  --accent-ink: #8A3018;
  --accent-soft: rgba(166, 61, 34, 0.07);
  --dark: #191612;
  --dark-2: #221E19;
  --dark-line: rgba(255, 255, 255, 0.12);

  --serif: "Songti SC", "STSong", "Noto Serif SC", "Source Han Serif SC", Georgia, serif;
  --sans: -apple-system, BlinkMacSystemFont, "PingFang SC", "Hiragino Sans GB",
          "Microsoft YaHei", "Noto Sans SC", sans-serif;
  --mono: ui-monospace, SFMono-Regular, Menlo, Consolas, "Liberation Mono", monospace;

  --wrap: 1120px;
  --radius: 3px;
}

/* ---------- 重置 ---------- */
* { box-sizing: border-box; }

html { -webkit-text-size-adjust: 100%; scroll-behavior: smooth; }

body {
  margin: 0;
  background: var(--paper);
  color: var(--ink);
  font-family: var(--sans);
  font-size: 16px;
  line-height: 1.75;
  -webkit-font-smoothing: antialiased;
  text-rendering: optimizeLegibility;
}

img, svg { max-width: 100%; }
a { color: inherit; text-decoration: none; }
button { font: inherit; color: inherit; }

h1, h2, h3, h4 {
  font-family: var(--serif);
  font-weight: 600;
  line-height: 1.3;
  margin: 0;
  letter-spacing: 0.01em;
}

p { margin: 0 0 1em; }
p:last-child { margin-bottom: 0; }

::selection { background: var(--accent); color: #fff; }

.wrap {
  width: 100%;
  max-width: var(--wrap);
  margin: 0 auto;
  padding: 0 28px;
}

/* ---------- 页头 ---------- */
.site-header {
  position: sticky;
  top: 0;
  z-index: 60;
  background: rgba(250, 248, 243, 0.82);
  backdrop-filter: saturate(180%) blur(12px);
  -webkit-backdrop-filter: saturate(180%) blur(12px);
  border-bottom: 1px solid transparent;
  transition: border-color 0.25s ease, background 0.25s ease;
}
.site-header.is-scrolled {
  border-bottom-color: var(--line);
  background: rgba(250, 248, 243, 0.94);
}

.header-inner {
  display: flex;
  align-items: center;
  gap: 28px;
  height: 68px;
}

.brand {
  display: flex;
  align-items: center;
  gap: 10px;
  flex-shrink: 0;
}
.brand-mark {
  display: grid;
  place-items: center;
  width: 34px;
  height: 34px;
  border: 1px solid var(--line-strong);
  border-radius: 50%;
  color: var(--accent);
}
.brand-text { display: flex; flex-direction: column; line-height: 1.15; }
.brand-text b {
  font-family: var(--serif);
  font-size: 1.02rem;
  font-weight: 600;
  letter-spacing: 0.06em;
}
.brand-text i {
  font-style: normal;
  font-size: 0.58rem;
  letter-spacing: 0.22em;
  color: var(--ink-3);
}

.nav {
  display: flex;
  gap: 30px;
  margin-left: auto;
  font-size: 0.94rem;
}
.nav a {
  position: relative;
  color: var(--ink-2);
  padding: 6px 0;
  transition: color 0.2s;
}
.nav a::after {
  content: "";
  position: absolute;
  left: 0; right: 0; bottom: 0;
  height: 1px;
  background: var(--accent);
  transform: scaleX(0);
  transform-origin: left;
  transition: transform 0.25s ease;
}
.nav a:hover { color: var(--ink); }
.nav a:hover::after,
.nav a[aria-current="page"]::after { transform: scaleX(1); }
.nav a[aria-current="page"] { color: var(--ink); }

.header-cta { flex-shrink: 0; }

.menu-toggle {
  display: none;
  width: 40px; height: 40px;
  border: 1px solid var(--line);
  border-radius: var(--radius);
  background: transparent;
  padding: 0;
  cursor: pointer;
  flex-direction: column;
  justify-content: center;
  align-items: center;
  gap: 4px;
}
.menu-toggle span {
  display: block;
  width: 16px; height: 1.5px;
  background: var(--ink);
  transition: transform 0.22s ease, opacity 0.22s ease;
}
.menu-toggle[aria-expanded="true"] span:nth-child(1) { transform: translateY(5.5px) rotate(45deg); }
.menu-toggle[aria-expanded="true"] span:nth-child(2) { opacity: 0; }
.menu-toggle[aria-expanded="true"] span:nth-child(3) { transform: translateY(-5.5px) rotate(-45deg); }

/* ---------- 按钮 ---------- */
.btn {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  padding: 11px 22px;
  border-radius: var(--radius);
  font-size: 0.92rem;
  letter-spacing: 0.02em;
  border: 1px solid transparent;
  cursor: pointer;
  transition: background 0.2s ease, color 0.2s ease, border-color 0.2s ease, transform 0.2s ease;
  white-space: nowrap;
}
.btn-solid {
  background: var(--ink);
  color: var(--paper);
  border-color: var(--ink);
}
.btn-solid:hover { background: var(--accent); border-color: var(--accent); }

.btn-line {
  border-color: var(--line-strong);
  color: var(--ink);
  background: transparent;
}
.btn-line:hover { border-color: var(--ink); background: rgba(23, 20, 15, 0.04); }

.btn-ghost {
  border-color: var(--line-strong);
  color: var(--ink);
  font-size: 0.88rem;
  padding: 9px 18px;
}
.btn-ghost:hover { background: var(--ink); color: var(--paper); border-color: var(--ink); }

.btn-on-dark { color: #F3EDE2; border-color: rgba(255,255,255,0.28); }
.btn-on-dark:hover { background: rgba(255,255,255,0.1); border-color: rgba(255,255,255,0.5); color: #fff; }

/* ---------- 首屏 ---------- */
.hero {
  position: relative;
  overflow: hidden;
  padding: 96px 0 84px;
  border-bottom: 1px solid var(--line);
}
/* 五线谱母题：五条极淡的横线 */
.hero .staff {
  position: absolute;
  inset: 0;
  background-image: repeating-linear-gradient(
    to bottom,
    transparent 0 47px,
    rgba(23, 20, 15, 0.055) 47px 48px
  );
  mask-image: linear-gradient(to bottom, rgba(0,0,0,0.9), transparent 78%);
  -webkit-mask-image: linear-gradient(to bottom, rgba(0,0,0,0.9), transparent 78%);
  pointer-events: none;
}
.hero-inner { position: relative; max-width: 860px; }

.eyebrow {
  font-size: 0.76rem;
  letter-spacing: 0.26em;
  text-transform: uppercase;
  color: var(--ink-3);
  margin: 0 0 22px;
}
.hero h1 {
  font-size: clamp(2.6rem, 6vw, 4.1rem);
  letter-spacing: 0.04em;
  margin-bottom: 26px;
}
.lede {
  font-size: clamp(1rem, 1.6vw, 1.12rem);
  color: var(--ink-2);
  line-height: 1.85;
  max-width: 46em;
}

.hero-actions {
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
  margin: 36px 0 0;
}

.hero-stats {
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: 28px;
  margin: 60px 0 0;
  padding-top: 28px;
  border-top: 1px solid var(--line);
}
.hero-stats dt {
  font-size: 0.74rem;
  letter-spacing: 0.16em;
  color: var(--ink-3);
  margin-bottom: 6px;
}
.hero-stats dd {
  margin: 0;
  font-size: 0.98rem;
  color: var(--ink);
}

/* ---------- 通用区块 ---------- */
.section { padding: 96px 0; border-bottom: 1px solid var(--line); }
.section-tight { padding: 64px 0 80px; }
.section-tint { background: var(--paper-2); }
.section-dark { background: var(--dark); color: #EDE7DC; border-bottom: none; }
.section-dark h2 { color: #F5F0E6; }
.section-dark .num, .section-dark .eyebrow { color: rgba(237, 231, 220, 0.5); }

.section-head { max-width: 780px; margin-bottom: 52px; }
.section-head h2 { font-size: clamp(1.7rem, 3.2vw, 2.3rem); margin-bottom: 14px; }
.section-sub { color: var(--ink-2); font-size: 1.02rem; }

.num {
  display: block;
  font-family: var(--mono);
  font-size: 0.72rem;
  letter-spacing: 0.2em;
  color: var(--accent);
  margin-bottom: 14px;
}

/* 两栏：左标签 + 右正文 */
.two-col {
  display: grid;
  grid-template-columns: 280px minmax(0, 1fr);
  gap: 64px;
  align-items: start;
}
.col-label h2 { font-size: clamp(1.5rem, 2.6vw, 1.95rem); position: sticky; top: 96px; }
.col-body .lead {
  font-size: 1.12rem;
  line-height: 1.85;
  color: var(--ink);
}

/* 要点列表 */
.point-list {
  list-style: none;
  padding: 0;
  margin: 28px 0 0;
  display: grid;
  gap: 1px;
  background: var(--line);
  border-top: 1px solid var(--line);
  border-bottom: 1px solid var(--line);
}
.point-list li {
  background: var(--paper);
  padding: 16px 0;
  display: grid;
  grid-template-columns: 128px minmax(0, 1fr);
  gap: 20px;
  align-items: baseline;
}
.point-list b { font-weight: 600; }
.point-list span { color: var(--ink-2); font-size: 0.96rem; }
.section-tint .point-list li { background: var(--paper-2); }
.point-list-lg li { padding: 20px 0; }

.note {
  font-size: 0.9rem;
  color: var(--ink-3);
  line-height: 1.8;
  margin-top: 24px;
}

/* ---------- 流水线 ---------- */
.pipeline {
  list-style: none;
  margin: 0;
  padding: 0;
  display: grid;
  grid-template-columns: repeat(4, minmax(0, 1fr));
  gap: 0;
  border-top: 1px solid var(--line-strong);
}
.pipeline li {
  padding: 28px 22px 28px 0;
  border-right: 1px solid var(--line);
  position: relative;
}
.pipeline li:last-child { border-right: none; }
.pipeline li::before {
  content: "";
  position: absolute;
  top: -4px; left: 0;
  width: 7px; height: 7px;
  border-radius: 50%;
  background: var(--accent);
}
.pipeline h3 { font-size: 1.05rem; margin-bottom: 10px; }
.pipeline p { font-size: 0.92rem; color: var(--ink-2); }
.pipeline li::after {
  content: "→";
  position: absolute;
  right: 10px;
  top: 26px;
  color: var(--line-strong);
  font-size: 0.9rem;
}
.pipeline li:last-child::after { content: none; }

/* ---------- 产品卡片 ---------- */
.feature {
  display: grid;
  grid-template-columns: 1.15fr 1fr;
  gap: 1px;
  background: var(--line);
  border: 1px solid var(--line);
  margin-bottom: 1px;
}
.feature-main, .feature-side {
  background: var(--paper);
  padding: 34px 32px 30px;
}
.feature-side { background: var(--paper-2); }
.feature h3 { font-size: 1.45rem; margin: 12px 0 10px; }
.feature p { font-size: 0.95rem; color: var(--ink-2); }

.link-arrow {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  margin-top: 18px;
  font-size: 0.92rem;
  color: var(--accent-ink);
  border-bottom: 1px solid transparent;
  transition: border-color 0.2s, gap 0.2s;
}
.link-arrow:hover { border-bottom-color: var(--accent-ink); gap: 10px; }

.card-row {
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: 1px;
  background: var(--line);
  border: 1px solid var(--line);
  border-top: none;
}
.card {
  background: var(--paper);
  padding: 30px 28px;
}
.card h3 { font-size: 1.18rem; margin: 12px 0 8px; }
.card p { font-size: 0.93rem; color: var(--ink-2); }

.tag {
  display: inline-block;
  font-size: 0.7rem;
  letter-spacing: 0.1em;
  padding: 3px 9px;
  border: 1px solid var(--line-strong);
  border-radius: 999px;
  color: var(--ink-2);
  background: var(--paper);
  white-space: nowrap;
}
.tag-live { border-color: #9CB08A; color: #4D6238; background: #F2F5EC; }
.tag-dev { border-color: var(--line-strong); color: var(--ink-2); background: var(--paper-3); }
.tag-plan { border-color: var(--line); color: var(--ink-3); background: transparent; }

/* ---------- 能力证明 ---------- */
.proof {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 64px;
  align-items: center;
  padding: 20px 0;
}
.proof-text h2 { font-size: clamp(1.7rem, 3vw, 2.2rem); margin: 12px 0 20px; }
.proof-text p { color: rgba(237, 231, 220, 0.78); font-size: 0.98rem; }
.proof-text .btn { margin-top: 26px; }

.proof-visual {
  border: 1px solid var(--dark-line);
  padding: 40px 32px;
  background: rgba(255,255,255,0.02);
}
.staff-block {
  display: flex;
  align-items: center;
  gap: 14px;
  font-family: var(--serif);
  font-size: 1.6rem;
  color: #F5F0E6;
  flex-wrap: wrap;
}
.staff-block .bar {
  width: 1.5px;
  height: 28px;
  background: rgba(255,255,255,0.35);
  margin: 0 4px;
}
.proof-caption {
  margin: 22px 0 0;
  font-size: 0.82rem;
  color: rgba(237, 231, 220, 0.5);
  letter-spacing: 0.04em;
}

/* ---------- 页面标题区 ---------- */
.page-head {
  padding: 80px 0 56px;
  border-bottom: 1px solid var(--line);
  background: linear-gradient(to bottom, var(--paper-2), var(--paper));
}
.page-head h1 { font-size: clamp(2rem, 4vw, 2.9rem); margin-bottom: 20px; }
.page-head-404 { padding: 110px 0 100px; }

/* ---------- 产品详情 ---------- */
.product {
  padding: 48px 0;
  border-top: 1px solid var(--line);
}
.product:first-child { border-top: none; padding-top: 0; }
.product-head {
  display: flex;
  justify-content: space-between;
  align-items: flex-end;
  gap: 24px;
  margin-bottom: 26px;
  flex-wrap: wrap;
}
.product-head h2 { font-size: clamp(1.5rem, 2.6vw, 1.95rem); margin: 12px 0 6px; }
.product-sub { color: var(--ink-3); font-size: 0.92rem; margin: 0; }
.product-body { max-width: 760px; }
.product-body p { color: var(--ink-2); }

.grid-4 {
  display: grid;
  grid-template-columns: repeat(4, minmax(0, 1fr));
  gap: 12px;
  margin: 26px 0;
}
.mini {
  border: 1px solid var(--line);
  padding: 16px 16px 18px;
  background: var(--paper);
}
.mini b { display: block; font-size: 0.92rem; margin-bottom: 6px; }
.mini span { font-size: 0.84rem; color: var(--ink-3); line-height: 1.6; }

.callout {
  border-left: 2px solid var(--accent);
  background: var(--accent-soft);
  padding: 24px 26px;
  margin-top: 28px;
}
.callout h3 { font-size: 1.05rem; margin-bottom: 10px; }
.callout p { font-size: 0.93rem; }

/* ---------- 曲谱库 ---------- */
.score-tabs {
  display: flex;
  gap: 8px;
  margin-bottom: 28px;
  flex-wrap: wrap;
}
.score-tab {
  padding: 8px 18px;
  border: 1px solid var(--line-strong);
  background: transparent;
  border-radius: 999px;
  font-size: 0.9rem;
  color: var(--ink-2);
  cursor: pointer;
  transition: all 0.2s;
}
.score-tab:hover { border-color: var(--ink); color: var(--ink); }
.score-tab.is-active {
  background: var(--ink);
  border-color: var(--ink);
  color: var(--paper);
}

.score-panel {
  border: 1px solid var(--line);
  background: var(--paper);
}

.score-meta {
  display: flex;
  justify-content: space-between;
  align-items: flex-start;
  gap: 28px;
  padding: 28px 30px;
  border-bottom: 1px solid var(--line);
  flex-wrap: wrap;
}
.score-meta h2 { font-size: 1.5rem; margin-bottom: 4px; }
.score-meta p { color: var(--ink-3); font-size: 0.86rem; margin: 0; }
.score-facts {
  display: flex;
  gap: 28px;
  margin: 0;
  flex-wrap: wrap;
}
.score-facts dt {
  font-size: 0.7rem;
  letter-spacing: 0.14em;
  color: var(--ink-3);
  margin-bottom: 2px;
}
.score-facts dd { margin: 0; font-size: 0.9rem; }

.score-stage {
  padding: 40px 30px;
  overflow-x: auto;
  /* 五线谱底纹：五条淡线，呼应唱名谱 */
  background-image: repeating-linear-gradient(
    to bottom,
    transparent 0 39px,
    rgba(23, 20, 15, 0.045) 39px 40px
  );
  background-position: 0 8px;
}

.score-sheet {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  row-gap: 26px;
  min-height: 90px;
}

.measure {
  display: flex;
  align-items: center;
  gap: 6px;
  padding-right: 26px;
  margin-right: 26px;
  border-right: 1.5px solid var(--line-strong);
  min-height: 58px;
}
.measure:last-child { border-right: none; }

.note {
  position: relative;
  display: inline-flex;
  align-items: center;
  font-family: var(--serif);
  font-size: 1.55rem;
  line-height: 1;
  padding: 6px 5px 4px;
  border-radius: 3px;
  cursor: pointer;
  transition: background 0.15s, color 0.15s, transform 0.15s;
  user-select: none;
}
.note:hover { background: rgba(23, 20, 15, 0.06); }
.note:focus-visible { outline: 2px solid var(--accent); outline-offset: 2px; }
.note .digit { font-weight: 500; }

/* 八分音符：下划线 */
.note.short { border-bottom: 1.5px solid currentColor; border-radius: 0; }
.note.short:hover { background: rgba(23, 20, 15, 0.06); }

/* 附点 */
.note .aug-dot { margin-left: 1px; font-size: 1.55rem; line-height: 1; }

/* 延长线 */
.note .hold {
  color: var(--ink-3);
  margin: 0 3px;
  font-size: 1.2rem;
}

/* 八度点 */
.note .oct-dot {
  position: absolute;
  width: 3px; height: 3px;
  border-radius: 50%;
  background: currentColor;
  left: 50%;
  transform: translateX(-50%);
}
.note .oct-dot.up { top: 2px; }
.note .oct-dot.down { bottom: 2px; }

/* 选中 / 播放中 */
.note.is-active {
  background: var(--ink);
  color: var(--paper);
}
.note.is-active .hold { color: rgba(250, 248, 243, 0.6); }
.note.playing {
  background: var(--accent);
  color: #fff;
  transform: translateY(-2px);
}

/* 控制条 */
.score-controls {
  display: flex;
  align-items: center;
  gap: 16px;
  padding: 22px 30px;
  border-top: 1px solid var(--line);
  flex-wrap: wrap;
}
.score-controls .hint {
  margin: 0 0 0 auto;
  font-size: 0.82rem;
  color: var(--ink-3);
}
#playBtn svg { flex-shrink: 0; }
#playBtn.is-playing { background: var(--accent); border-color: var(--accent); }

/* 音符详情 */
.note-inspector {
  display: flex;
  gap: 34px;
  flex-wrap: wrap;
  padding: 20px 30px;
  border-top: 1px solid var(--line);
  background: var(--paper-2);
  min-height: 66px;
  align-items: center;
}
.inspector-idle { color: var(--ink-3); font-size: 0.9rem; }
.ins-row { display: flex; align-items: baseline; gap: 10px; }
.ins-row i {
  font-style: normal;
  font-size: 0.72rem;
  letter-spacing: 0.12em;
  color: var(--ink-3);
}
.ins-row b { font-size: 0.95rem; font-weight: 600; }

/* MusicXML */
.xml-view {
  margin: 0;
  padding: 24px 30px;
  border-top: 1px solid var(--line);
  background: var(--dark);
  color: #D9D2C4;
  font-family: var(--mono);
  font-size: 0.78rem;
  line-height: 1.7;
  max-height: 380px;
  overflow: auto;
}
.xml-view code { white-space: pre; }

.note-foot { max-width: 640px; }

/* ---------- 联系页 ---------- */
.contact-grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 1px;
  background: var(--line);
  border: 1px solid var(--line);
}
.contact-card {
  background: var(--paper);
  padding: 36px 34px;
}
.contact-card-tint { background: var(--paper-2); }
.contact-card h2 { font-size: 1.3rem; margin-bottom: 22px; }

.contact-line {
  display: flex;
  gap: 18px;
  align-items: baseline;
  padding: 12px 0;
  border-bottom: 1px solid var(--line);
  margin: 0;
}
.contact-line span {
  font-size: 0.76rem;
  letter-spacing: 0.14em;
  color: var(--ink-3);
  min-width: 42px;
}
.contact-line a, .contact-line b {
  font-size: 1rem;
  font-weight: 500;
}
.contact-line a { color: var(--accent-ink); }
.contact-line a:hover { text-decoration: underline; }

.steps {
  list-style: none;
  counter-reset: step;
  padding: 0;
  margin: 0;
}
.steps li {
  counter-increment: step;
  position: relative;
  padding: 0 0 22px 40px;
  border-left: 1px solid var(--line-strong);
  margin-left: 8px;
}
.steps li:last-child { border-left-color: transparent; padding-bottom: 0; }
.steps li::before {
  content: counter(step);
  position: absolute;
  left: -9px; top: 0;
  width: 17px; height: 17px;
  border-radius: 50%;
  background: var(--paper-2);
  border: 1px solid var(--line-strong);
  font-family: var(--mono);
  font-size: 0.62rem;
  display: grid;
  place-items: center;
  color: var(--ink-2);
}
.steps b { display: block; font-size: 0.98rem; margin-bottom: 4px; }
.steps span { font-size: 0.9rem; color: var(--ink-2); }

/* ---------- 页脚 ---------- */
.site-footer {
  background: var(--paper);
  padding: 64px 0 32px;
}
.footer-inner {
  display: flex;
  justify-content: space-between;
  gap: 48px;
  flex-wrap: wrap;
  padding-bottom: 40px;
  border-bottom: 1px solid var(--line);
}
.footer-brand b {
  font-family: var(--serif);
  font-size: 1.05rem;
  letter-spacing: 0.04em;
}
.footer-brand p {
  margin: 8px 0 0;
  color: var(--ink-3);
  font-size: 0.9rem;
  letter-spacing: 0.06em;
}
.footer-links { display: flex; gap: 72px; flex-wrap: wrap; }
.footer-links h4 {
  font-family: var(--sans);
  font-size: 0.72rem;
  letter-spacing: 0.16em;
  color: var(--ink-3);
  font-weight: 500;
  margin-bottom: 14px;
}
.footer-links a {
  display: block;
  font-size: 0.9rem;
  color: var(--ink-2);
  padding: 4px 0;
  transition: color 0.2s;
}
.footer-links a:hover { color: var(--accent); }

.footer-bottom {
  display: flex;
  justify-content: space-between;
  gap: 20px;
  flex-wrap: wrap;
  padding-top: 24px;
  font-size: 0.82rem;
  color: var(--ink-3);
}
.footer-bottom a:hover { color: var(--ink-2); text-decoration: underline; }

/* ---------- 响应式 ---------- */
@media (max-width: 960px) {
  .two-col { grid-template-columns: 1fr; gap: 28px; }
  .col-label h2 { position: static; }
  .pipeline { grid-template-columns: repeat(2, 1fr); }
  .pipeline li:nth-child(2) { border-right: none; }
  .pipeline li::after { content: none; }
  .feature { grid-template-columns: 1fr; }
  .card-row { grid-template-columns: 1fr; }
  .grid-4 { grid-template-columns: repeat(2, 1fr); }
  .proof { grid-template-columns: 1fr; gap: 40px; }
  .contact-grid { grid-template-columns: 1fr; }
  .hero-stats { grid-template-columns: 1fr; gap: 18px; }
}

@media (max-width: 760px) {
  .wrap { padding: 0 20px; }
  .section { padding: 64px 0; }
  .hero { padding: 64px 0 56px; }
  .header-cta { display: none; }

  .menu-toggle { display: flex; margin-left: auto; }
  .nav {
    position: fixed;
    inset: 68px 0 auto 0;
    background: var(--paper);
    border-bottom: 1px solid var(--line);
    flex-direction: column;
    gap: 0;
    padding: 8px 20px 20px;
    transform: translateY(-110%);
    transition: transform 0.28s ease;
    z-index: 50;
    /* 收起时不能拦截页头的点击(transform 后边界仍与页头重叠) */
    visibility: hidden;
    pointer-events: none;
    transition: transform 0.28s ease, visibility 0s 0.28s;
  }
  .nav.is-open {
    transform: translateY(0);
    visibility: visible;
    pointer-events: auto;
    transition: transform 0.28s ease;
  }
  .nav a { padding: 14px 0; border-bottom: 1px solid var(--line); }
  .nav a::after { display: none; }
  body.nav-open { overflow: hidden; }

  .point-list li { grid-template-columns: 1fr; gap: 4px; }
  .pipeline { grid-template-columns: 1fr; }
  .pipeline li { border-right: none; border-bottom: 1px solid var(--line); padding-right: 0; }
  .grid-4 { grid-template-columns: 1fr; }

  .score-meta { padding: 22px 20px; }
  .score-stage { padding: 28px 20px; }
  .score-controls { padding: 18px 20px; }
  .score-controls .hint { display: none; }
  .note-inspector { padding: 16px 20px; gap: 18px; }
  .xml-view { padding: 18px 20px; font-size: 0.72rem; }
  .measure { padding-right: 16px; margin-right: 16px; }
  .note { font-size: 1.35rem; }

  .footer-inner { flex-direction: column; gap: 32px; }
  .footer-links { gap: 40px; }
}

@media (prefers-reduced-motion: reduce) {
  *, *::before, *::after {
    animation-duration: 0.01ms !important;
    transition-duration: 0.01ms !important;
    scroll-behavior: auto !important;
  }
}