/* suisuinian · brand site
   tokens — based on BrandMark.swift v2 (stroke 160) */

:root {
  --coral:       #E85A6E;
  --coral-dark:  #F47D8E;
  --label:       #0A0A0C;
  --label-2:     #3A3A3C;
  --text:        #3A3128;
  --surface:     #FAFAF7;
  --bg:          #FFFFFF;
  --muted:       #8A8A8E;
  --hairline:    rgba(0, 0, 0, 0.08);
  --hairline-2:  rgba(0, 0, 0, 0.06);

  --font-sans:  "SF Pro Display", "Inter", -apple-system, BlinkMacSystemFont, system-ui, "PingFang SC", sans-serif;
  --font-cn:    "PingFang SC", -apple-system, BlinkMacSystemFont, system-ui, sans-serif;
  --font-mono:  ui-monospace, "SF Mono", Menlo, monospace;

  --container:  1200px;
  --pad-x:      56px;
  --pad-x-sm:   24px;

  --radius-sm:  6px;
  --radius:     10px;
  --radius-lg:  14px;

  --ease-out:   cubic-bezier(0.16, 1, 0.3, 1);
}

* { box-sizing: border-box; }

html { scroll-behavior: smooth; }
@media (prefers-reduced-motion: reduce) {
  html { scroll-behavior: auto; }
}

html, body {
  margin: 0;
  padding: 0;
  background: var(--surface);
  color: var(--text);
  font-family: var(--font-sans);
  font-size: 14px;
  line-height: 1.65;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
}

a { color: inherit; text-decoration: none; }
a:hover { color: var(--coral); }

/* ── mark color variants ── */

.mark { display: block; color: var(--label); }
.mark--coral       { color: var(--coral); }
.mark--coral-dark  { color: var(--coral-dark); }
.mark--white       { color: #FFFFFF; }

/* knockout 内圆默认底色;深色容器内通过 inline style 覆盖 */
.mark .axis-knockout { fill: var(--bg); }
.dark .mark .axis-knockout,
.mark.on-dark .axis-knockout { fill: var(--label); }
.mark.on-coral .axis-knockout { fill: var(--coral); }

/* ── container ── */

.container {
  max-width: var(--container);
  margin: 0 auto;
  padding: 0 var(--pad-x);
}

/* ── nav ── */

.nav {
  background: var(--surface);
  border-bottom: 0.5px solid var(--hairline-2);
  position: sticky;
  top: 0;
  z-index: 50;
  backdrop-filter: saturate(180%) blur(20px);
  -webkit-backdrop-filter: saturate(180%) blur(20px);
  background: rgba(250, 250, 247, 0.85);
}
.nav__inner {
  max-width: var(--container);
  margin: 0 auto;
  padding: 14px var(--pad-x);
  display: flex;
  align-items: center;
  gap: 24px;
}
.nav__links {
  display: flex;
  gap: 22px;
  margin-left: auto;
  font-size: 13px;
  color: var(--text);
  align-items: center;
}
.nav__links a:hover { color: var(--coral); }
.nav__cta {
  padding: 8px 16px;
  background: var(--label);
  color: #fff;
  border-radius: 7px;
  font-size: 13px;
  font-weight: 600;
  transition: background 0.18s var(--ease-out);
}
.nav__cta:hover { background: #1a1a1c; color: #fff; }

/* language switcher · 紧贴 CTA 左侧 */
.nav__lang {
  display: inline-flex;
  align-items: center;
  gap: 1px;
  padding: 3px;
  background: rgba(0, 0, 0, 0.04);
  border-radius: 7px;
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: 0.5px;
}
.nav__lang a {
  padding: 4px 8px;
  border-radius: 5px;
  color: var(--muted);
  transition: all 0.16s var(--ease-out);
  line-height: 1;
}
.nav__lang a:hover { color: var(--label); }
.nav__lang a.is-active {
  background: #fff;
  color: var(--label);
  font-weight: 600;
  box-shadow: 0 0 0 0.5px var(--hairline), 0 1px 2px rgba(0,0,0,0.04);
}

/* ── lockup ── */

.lockup { display: flex; align-items: center; gap: 12px; }
.lockup__text {
  display: flex;
  flex-direction: column;
  gap: 1px;
  line-height: 1;
}
.lockup__en {
  font-size: 16px;
  font-weight: 700;
  letter-spacing: -0.4px;
  color: var(--label);
  font-family: var(--font-sans);
}
.lockup__cn {
  font-size: 9px;
  font-weight: 500;
  color: var(--label);
  opacity: 0.55;
  font-family: var(--font-cn);
  letter-spacing: 4px;
}

/* large lockup for hero / brand */
.lockup--lg .lockup__en { font-size: 26px; letter-spacing: -0.6px; }
.lockup--lg .lockup__cn { font-size: 13px; letter-spacing: 6px; }

/* ── hero ── */

.hero {
  background: var(--surface);
  padding: clamp(64px, 7vw, 96px) 0 clamp(72px, 8vw, 104px);
  position: relative;
  overflow: hidden;
}
/* hero 底部细 coral 渐变指示带 → section 之间不再硬切 */
.hero::after {
  content: "";
  position: absolute;
  left: 0; right: 0; bottom: 0;
  height: 1px;
  background: linear-gradient(90deg, transparent 0%, rgba(232,90,110,0.35) 30%, rgba(232,90,110,0.35) 70%, transparent 100%);
}
/* scroll cue · 浮在 hero 底部 hairline 中央 */
.scroll-cue {
  position: absolute;
  left: 50%;
  bottom: -16px;
  transform: translateX(-50%);
  display: inline-flex;
  align-items: center;
  gap: 8px;
  padding: 6px 12px;
  background: var(--surface);
  border: 0.5px solid rgba(232, 90, 110, 0.3);
  border-radius: 999px;
  font-family: var(--font-mono);
  font-size: 10.5px;
  letter-spacing: 1px;
  color: var(--muted);
  z-index: 1;
  pointer-events: auto;
  cursor: pointer;
  transition: color 0.2s var(--ease-out), border-color 0.2s var(--ease-out);
}
.scroll-cue:hover { color: var(--coral); border-color: var(--coral); }
.scroll-cue .arrow {
  display: inline-block;
  animation: cue-bounce 2.4s ease-in-out infinite;
}
@keyframes cue-bounce {
  0%, 100% { transform: translateY(0); }
  50%      { transform: translateY(3px); }
}
.hero__inner {
  display: grid;
  grid-template-columns: 1.1fr 1fr;
  gap: 56px;
  align-items: center;
}
.eyebrow {
  font-size: 11px;
  letter-spacing: 3px;
  color: var(--muted);
  text-transform: uppercase;
  font-family: var(--font-sans);
  margin-bottom: 22px;
}
.hero__title {
  font-family: var(--font-cn);
  font-size: 56px;
  line-height: 1.18;
  font-weight: 700;
  color: var(--label);
  letter-spacing: -1px;
  margin: 0 0 20px;
}
.hero__title .accent { color: var(--coral); }
/* English hero title — sans font, larger to match Chinese density */
.hero__title--en {
  font-family: var(--font-sans);
  font-size: clamp(48px, 6.2vw, 80px);
  line-height: 1.02;
  letter-spacing: -2.4px;
}
.hero__desc {
  font-size: 15px;
  line-height: 1.75;
  color: var(--text);
  max-width: 380px;
  margin: 0 0 28px;
}
.hero__cta-row {
  display: flex;
  gap: 12px;
  flex-wrap: wrap;
  margin-bottom: 18px;
}
.btn {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  padding: 14px 26px;
  border-radius: 9px;
  font-size: 14px;
  font-weight: 600;
  transition: all 0.18s var(--ease-out);
  cursor: pointer;
  border: none;
}
.btn--primary {
  background: var(--label);
  color: #fff;
  box-shadow: 0 1px 0 rgba(255,255,255,0.08) inset, 0 8px 18px -8px rgba(0,0,0,0.4);
}
.btn--primary:hover {
  background: #1a1a1c;
  color: #fff;
  transform: translateY(-1px);
  box-shadow: 0 1px 0 rgba(255,255,255,0.08) inset, 0 14px 24px -10px rgba(0,0,0,0.45);
}
.btn--ghost {
  background: transparent;
  color: var(--label);
  border: 0.5px solid rgba(0, 0, 0, 0.22);
  font-weight: 500;
}
.btn--ghost:hover {
  border-color: var(--label);
  color: var(--label);
  background: rgba(0,0,0,0.02);
}
/* 外链右上箭头 */
.btn[target="_blank"]::after,
a.ext::after { content: " ↗"; opacity: 0.7; font-weight: 400; }

/* CTA status pill · 用于「即将上线」/「Coming soon」 */
.btn__status {
  margin-left: 8px;
  padding: 2px 6px;
  background: rgba(255, 255, 255, 0.16);
  border-radius: 4px;
  font-size: 9.5px;
  font-weight: 600;
  letter-spacing: 0.6px;
  text-transform: uppercase;
  font-family: var(--font-mono);
  vertical-align: 1px;
}
.hero__caption {
  font-size: 11px;
  color: var(--muted);
  font-family: var(--font-mono);
  letter-spacing: 0.4px;
}
.hero__mark {
  flex-shrink: 0;
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  gap: 28px;
}
.hero__mark svg { width: 320px; height: 320px; }
/* hero 右列底部 status chip · 让右列不再是纯图 */
.hero__status {
  display: inline-flex;
  align-items: center;
  gap: 10px;
  padding: 8px 14px 8px 12px;
  background: rgba(0, 0, 0, 0.04);
  border-radius: 999px;
  font-family: var(--font-mono);
  font-size: 11px;
  color: var(--text);
  letter-spacing: 0.3px;
}
.hero__status .dot {
  width: 6px; height: 6px;
  border-radius: 50%;
  background: var(--coral);
  box-shadow: 0 0 0 4px rgba(232, 90, 110, 0.12);
  animation: status-blink 2.6s ease-in-out infinite;
}
@keyframes status-blink {
  0%, 100% { opacity: 1; }
  50%      { opacity: 0.45; }
}
.hero__status .sep {
  width: 1px; height: 10px;
  background: rgba(0, 0, 0, 0.15);
}

/* ── sections ── */

.section {
  padding: clamp(56px, 6.5vw, 88px) 0;
  background: var(--bg);
}
.section--alt { background: var(--surface); }
.section--dark {
  background: var(--label);
  color: rgba(255, 255, 255, 0.82);
  position: relative;
}
/* dark section 顶部 + 底部 1px coral hairline · 给重黑色块加边界 */
.section--dark::before,
.section--dark::after {
  content: "";
  position: absolute;
  left: 0; right: 0;
  height: 1px;
  background: linear-gradient(90deg, transparent 0%, rgba(244,125,142,0.5) 20%, rgba(244,125,142,0.5) 80%, transparent 100%);
}
.section--dark::before { top: 0; }
.section--dark::after  { bottom: 0; }
.section--platforms { padding: clamp(48px, 5vw, 64px) 0; }
.section--dark .eyebrow { color: rgba(255, 255, 255, 0.45); }
.section--dark h2 { color: #fff; }

.section__head {
  display: flex;
  align-items: baseline;
  gap: 12px;
  margin-bottom: 36px;
}
.section__head .eyebrow { margin-bottom: 0; }
.section h2 {
  font-family: var(--font-cn);
  font-size: clamp(28px, 3vw, 38px);
  font-weight: 700;
  color: var(--label);
  letter-spacing: -0.5px;
  margin: 0;
  line-height: 1.25;
}
.section--dark h2 { color: #fff; }

/* feature grid · 它是什么 */
.features {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 20px;
  position: relative;
}
/* connector arrows · 两个间隙各一条虚线 + 箭头, 暗示 capture → process → sync 的流水线 */
.features::before,
.features::after {
  content: "→";
  position: absolute;
  top: 50%;
  transform: translate(-50%, -50%);
  color: rgba(232, 90, 110, 0.55);
  font-family: var(--font-mono);
  font-size: 16px;
  font-weight: 400;
  width: 24px;
  height: 24px;
  display: flex;
  align-items: center;
  justify-content: center;
  background: var(--bg);
  border-radius: 50%;
  z-index: 1;
  pointer-events: none;
}
.section--alt .features::before,
.section--alt .features::after { background: var(--surface); }
.features::before { left: 33.333%; }
.features::after  { left: 66.666%; }
.feature {
  background: var(--bg);
  border: 0.5px solid var(--hairline);
  border-radius: var(--radius-lg);
  padding: 28px 26px;
  transition: transform 0.24s var(--ease-out), box-shadow 0.24s var(--ease-out);
}
.section--alt .feature { background: #fff; }
.feature:hover {
  transform: translateY(-3px);
  box-shadow: 0 18px 40px rgba(0, 0, 0, 0.06);
}
.feature__icon {
  width: 52px;
  height: 52px;
  border-radius: 14px;
  background: linear-gradient(135deg, rgba(232, 90, 110, 0.10) 0%, rgba(232, 90, 110, 0.04) 100%);
  display: flex;
  align-items: center;
  justify-content: center;
  margin-bottom: 22px;
  color: var(--coral);
  position: relative;
  overflow: hidden;
}
.feature__icon::after {
  content: "";
  position: absolute;
  inset: 0;
  border-radius: 14px;
  box-shadow: inset 0 0 0 0.5px rgba(232, 90, 110, 0.2);
  pointer-events: none;
}
.feature__icon svg { width: 26px; height: 26px; }
.feature h3 {
  font-family: var(--font-cn);
  font-size: 17px;
  font-weight: 600;
  color: var(--label);
  margin: 0 0 8px;
  letter-spacing: 0;
}
.feature p {
  font-size: 13.5px;
  line-height: 1.7;
  color: var(--text);
  margin: 0;
}

/* async loop section */
.loop {
  display: grid;
  grid-template-columns: auto 1fr;
  gap: 56px;
  align-items: center;
}

/* async loop · 3-node 流程图 (在 .loop 下方) */
.flow {
  margin-top: 56px;
  display: grid;
  grid-template-columns: 1fr 56px 1fr 56px 1fr;
  align-items: center;
  max-width: 880px;
}
.flow__node {
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 12px;
  text-align: center;
}
.flow__device {
  width: 88px;
  height: 88px;
  border-radius: 18px;
  border: 0.5px solid rgba(255, 255, 255, 0.18);
  background: rgba(255, 255, 255, 0.03);
  display: flex;
  align-items: center;
  justify-content: center;
  color: rgba(255, 255, 255, 0.55);
  position: relative;
  overflow: hidden;
}
.flow__device svg.icon { width: 38px; height: 38px; }
.flow__device .flow__pulse {
  position: absolute;
  inset: 0;
  display: flex;
  align-items: center;
  justify-content: center;
}
.flow__device .flow__pulse svg { width: 56px; height: 56px; color: var(--coral-dark); }
.flow__label {
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: 0.5px;
  color: rgba(255, 255, 255, 0.7);
}
.flow__sub {
  font-size: 11px;
  color: rgba(255, 255, 255, 0.45);
  margin-top: -6px;
}
.flow__conn {
  height: 1px;
  position: relative;
  background: linear-gradient(90deg,
    rgba(244, 125, 142, 0) 0%,
    rgba(244, 125, 142, 0.5) 30%,
    rgba(244, 125, 142, 0.5) 70%,
    rgba(244, 125, 142, 0) 100%);
}
.flow__conn::after {
  content: "→";
  position: absolute;
  right: -4px;
  top: 50%;
  transform: translateY(-50%);
  color: rgba(244, 125, 142, 0.8);
  font-family: var(--font-mono);
  font-size: 12px;
}
/* 让中间节点 (vault) 的小 mark 与 axis 一起脉冲, 共享品牌动效 */
.flow__pulse .axis {
  transform-origin: 496px 538px;
  animation: axis-pulse 1.6s ease-in-out infinite;
}
.loop__mark {
  background: var(--label);
  border-radius: 18px;
  padding: 32px;
  display: flex;
  align-items: center;
  justify-content: center;
}
.loop__copy h3 {
  font-family: var(--font-cn);
  font-size: 24px;
  font-weight: 700;
  color: #fff;
  margin: 0 0 16px;
  letter-spacing: -0.3px;
}
.loop__copy p {
  font-size: 14.5px;
  line-height: 1.8;
  color: rgba(255, 255, 255, 0.72);
  margin: 0 0 12px;
  max-width: 560px;
}
.loop__copy strong { color: #fff; font-weight: 600; }

/* platforms */
.platforms {
  display: flex;
  gap: 12px;
  flex-wrap: wrap;
}
.chip {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  padding: 8px 14px;
  background: #fff;
  border: 0.5px solid var(--hairline);
  border-radius: 999px;
  font-size: 12.5px;
  color: var(--text);
  font-family: var(--font-mono);
  letter-spacing: 0.3px;
}
.chip__dot {
  width: 6px;
  height: 6px;
  border-radius: 50%;
  background: var(--coral);
}

/* platforms · 三条平台信息 · 不用图片占位 */
.platform-list {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 20px;
  margin-top: 28px;
  margin-bottom: 28px;
  max-width: 900px;
}
.platform {
  padding-top: 16px;
  border-top: 0.5px solid var(--hairline);
}
.platform__head {
  display: flex;
  align-items: center;
  gap: 10px;
}
.platform__icon {
  width: 20px;
  height: 20px;
  color: var(--label-2);
  flex: none;
}
.platform__name {
  font-family: var(--font-mono);
  font-size: 13px;
  color: var(--label);
  letter-spacing: 0.2px;
}
.platform__sub {
  margin-top: 6px;
  font-size: 12.5px;
  color: var(--muted);
  font-family: var(--font-mono);
  letter-spacing: 0.2px;
}

/* ── footer ── */

.footer {
  background: var(--label);
  color: rgba(255, 255, 255, 0.65);
  padding: 64px 0 36px;
}
.footer__inner {
  display: grid;
  grid-template-columns: 1.4fr 1fr 1fr 1fr;
  gap: 36px;
}
.footer .lockup__en,
.footer .lockup__cn { color: #fff; }
.footer .lockup__cn { opacity: 0.6; }
.footer__slogan {
  font-family: var(--font-cn);
  font-size: 17px;
  color: #fff;
  margin: 18px 0 6px;
  line-height: 1.5;
}
.footer__slogan .accent { color: var(--coral-dark); }
.footer__slogan--en {
  font-family: var(--font-sans);
  font-weight: 600;
  letter-spacing: -0.3px;
}
.footer__slogan-en {
  font-size: 11px;
  font-family: var(--font-mono);
  color: rgba(255, 255, 255, 0.45);
  letter-spacing: 0.4px;
  font-style: italic;
}
.footer h4 {
  font-size: 11px;
  letter-spacing: 1.6px;
  text-transform: uppercase;
  color: rgba(255, 255, 255, 0.5);
  margin: 0 0 14px;
  font-weight: 600;
}
.footer ul {
  list-style: none;
  margin: 0;
  padding: 0;
}
.footer li {
  font-size: 13px;
  margin-bottom: 8px;
}
.footer li a:hover { color: var(--coral-dark); }
.footer__base {
  margin-top: 48px;
  padding-top: 24px;
  border-top: 0.5px solid rgba(255, 255, 255, 0.1);
  display: flex;
  justify-content: space-between;
  font-size: 11px;
  color: rgba(255, 255, 255, 0.4);
  font-family: var(--font-mono);
  letter-spacing: 0.3px;
}

/* ── brand page ── */

.brand-page {
  background: #F2F2EF;
  padding: 64px 0 96px;
}
.brand-page .container > .eyebrow { margin-bottom: 8px; }
.brand-page h1 {
  font-size: 32px;
  font-weight: 700;
  color: var(--label);
  letter-spacing: -0.5px;
  margin: 0 0 12px;
}
.brand-page .intro {
  font-size: 14px;
  color: var(--text);
  line-height: 1.7;
  max-width: 720px;
  margin-bottom: 48px;
}
.brand-section { margin-bottom: 56px; }
.brand-section__head {
  display: flex;
  align-items: baseline;
  gap: 10px;
  margin-bottom: 18px;
}
.brand-section__num {
  font-family: var(--font-mono);
  font-size: 11px;
  color: var(--muted);
}
.brand-section__title {
  font-size: 18px;
  font-weight: 600;
  color: var(--label);
  letter-spacing: -0.2px;
}
.brand-section__sub {
  font-size: 12px;
  color: #6e6e73;
}

.codeblock {
  background: var(--label);
  color: #E6E6EA;
  padding: 20px 22px;
  border-radius: 10px;
  font-family: var(--font-mono);
  font-size: 12.5px;
  line-height: 1.75;
  overflow-x: auto;
  margin: 0;
  white-space: pre;
}
.codeblock .c-comment { color: #8a8a8e; }
.codeblock .c-tag     { color: #8db8ff; }
.codeblock .c-attr    { color: #f0d080; }
.codeblock .c-string  { color: #e2a8a8; }

.brand-note {
  font-size: 12px;
  color: #6e6e73;
  margin-top: 12px;
  line-height: 1.7;
  max-width: 760px;
}
.brand-note code {
  background: #fff;
  padding: 1px 6px;
  border-radius: 3px;
  font-family: var(--font-mono);
  font-size: 11.5px;
  color: var(--label);
}

/* clearspace demo */
.clearspace {
  display: flex;
  gap: 28px;
  align-items: center;
  flex-wrap: wrap;
}
.clearspace__box {
  position: relative;
  width: 320px;
  height: 320px;
  background: #fff;
  border-radius: var(--radius);
  box-shadow: 0 0 0 0.5px var(--hairline);
  display: flex;
  align-items: center;
  justify-content: center;
}
.clearspace__guide {
  position: absolute;
  inset: 50px;
  border: 2px dashed var(--coral);
  border-radius: 6px;
  opacity: 0.5;
  pointer-events: none;
}
.clearspace__x {
  position: absolute;
  top: 50%;
  left: 0;
  width: 50px;
  border-top: 1px dashed var(--coral);
  opacity: 0.8;
}
.clearspace__x-label {
  position: absolute;
  top: calc(50% - 18px);
  left: 18px;
  font-family: var(--font-mono);
  font-size: 10px;
  color: var(--coral);
}
.clearspace__copy {
  flex: 1;
  min-width: 280px;
  max-width: 360px;
  font-size: 13px;
  color: var(--text);
  line-height: 1.8;
}
.clearspace__copy strong { color: var(--label); }

/* color spec */
.colors {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 12px;
}
.color {
  display: flex;
  gap: 12px;
  align-items: center;
  background: #fff;
  padding: 12px 14px;
  border-radius: 8px;
  box-shadow: 0 0 0 0.5px var(--hairline);
}
.color__swatch {
  width: 38px;
  height: 38px;
  border-radius: 7px;
  border: 0.5px solid rgba(0, 0, 0, 0.06);
  flex-shrink: 0;
}
.color__name { font-size: 12.5px; font-weight: 600; color: var(--label); }
.color__hex  { font-size: 10.5px; color: #6e6e73; font-family: var(--font-mono); }
.color__use  { font-size: 10.5px; color: var(--muted); margin-top: 1px; }

/* motion demos */
.motion-grid {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 20px;
  max-width: 760px;
}
.motion-card {
  background: #fff;
  border-radius: 10px;
  padding: 22px 24px;
  box-shadow: 0 0 0 0.5px var(--hairline);
}
.motion-card h4 {
  font-size: 12px;
  font-weight: 600;
  color: var(--label);
  margin: 0 0 12px;
}
.motion-card__demo {
  display: flex;
  justify-content: center;
  margin-bottom: 12px;
}
.motion-card p {
  font-size: 11.5px;
  color: #6e6e73;
  margin: 0;
  line-height: 1.65;
}

/* don't / do grids */
.examples {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 14px;
}
.example {
  background: #fff;
  border-radius: 10px;
  padding: 14px;
  box-shadow: 0 0 0 0.5px var(--hairline);
}
.example__frame {
  position: relative;
  width: 100%;
  aspect-ratio: 1;
  margin-bottom: 10px;
  background: var(--surface);
  border-radius: 6px;
  display: flex;
  align-items: center;
  justify-content: center;
  overflow: hidden;
}
.example--dont .example__frame::after {
  content: "";
  position: absolute;
  inset: 6%;
  border-top: 1.5px solid rgba(224, 74, 56, 0.6);
  transform: rotate(45deg);
  transform-origin: 0 50%;
  width: 130%;
  pointer-events: none;
}
.example__title {
  font-size: 11.5px;
  font-weight: 600;
  color: var(--label);
  margin-bottom: 4px;
}
.example__desc {
  font-size: 10.5px;
  color: #6e6e73;
  line-height: 1.55;
}

/* file delivery grid */
.files {
  background: #fff;
  border-radius: 10px;
  padding: 22px 26px;
  box-shadow: 0 0 0 0.5px var(--hairline);
  max-width: 800px;
}
.files__grid {
  display: grid;
  grid-template-columns: auto 1fr;
  row-gap: 8px;
  column-gap: 18px;
  font-family: var(--font-mono);
  font-size: 12px;
  line-height: 1.6;
}
.files__name { color: var(--label); }
.files__desc { color: #6e6e73; }

.legal-note {
  padding: 16px 20px;
  background: rgba(232, 90, 110, 0.08);
  border-radius: 10px;
  border: 0.5px solid rgba(232, 90, 110, 0.3);
  font-size: 12.5px;
  color: var(--text);
  line-height: 1.85;
  max-width: 760px;
}

/* ── docs page ── */

.docs-layout {
  display: grid;
  grid-template-columns: 240px 1fr;
  gap: 0;
  min-height: calc(100vh - 60px);
  background: #fff;
}
.docs-sidebar {
  background: var(--surface);
  padding: 28px 22px;
  border-right: 0.5px solid var(--hairline-2);
}
.docs-sidebar__group { margin-bottom: 22px; }
.docs-sidebar__label {
  font-size: 10px;
  color: var(--muted);
  letter-spacing: 1.4px;
  text-transform: uppercase;
  margin-bottom: 8px;
  font-weight: 600;
}
.docs-sidebar__link {
  display: block;
  font-size: 13px;
  color: var(--text);
  padding: 5px 0;
  line-height: 1.5;
}
.docs-sidebar__link--active { color: var(--coral); font-weight: 600; }
.docs-sidebar__link--disabled { color: #c0c0c4; cursor: not-allowed; }
.docs-sidebar__link--disabled:hover { color: #c0c0c4; }

.docs-content {
  padding: 48px 56px 64px;
  max-width: 820px;
}
.docs-crumb {
  font-size: 11.5px;
  color: var(--muted);
  margin-bottom: 10px;
  letter-spacing: 0.2px;
}
.docs-content h1 {
  font-family: var(--font-cn);
  font-size: 32px;
  font-weight: 700;
  color: var(--label);
  letter-spacing: -0.5px;
  margin: 0 0 16px;
}
.docs-content p {
  font-size: 14px;
  color: var(--text);
  line-height: 1.85;
  margin: 0 0 20px;
  max-width: 680px;
}
.docs-content .codeblock { max-width: 680px; }
.docs-placeholder-banner {
  margin-top: 36px;
  padding: 18px 22px;
  background: rgba(232, 90, 110, 0.08);
  border: 0.5px solid rgba(232, 90, 110, 0.3);
  border-radius: 10px;
  font-size: 13px;
  color: var(--text);
  max-width: 680px;
  line-height: 1.75;
}
.docs-placeholder-banner strong { color: var(--label); }

/* sticky nav 高度补偿 · 锚点跳转不被 nav 盖住 */
section[id],
.docs-content h1[id] { scroll-margin-top: 78px; }

/* ── MCP section · 开放 ── */

.mcp-lead {
  font-size: 15px;
  line-height: 1.8;
  color: var(--text);
  max-width: 680px;
  margin: 12px 0 36px;
}
.mcp-grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 20px;
}
.mcp-panel {
  background: var(--surface);
  border: 0.5px solid var(--hairline);
  border-radius: var(--radius-lg);
  padding: 26px 24px;
  display: flex;
  flex-direction: column;
}
.mcp-panel__label {
  font-size: 10px;
  color: var(--muted);
  letter-spacing: 1.4px;
  text-transform: uppercase;
  font-weight: 600;
  font-family: var(--font-mono);
  margin-bottom: 18px;
}
.mcp-panel__foot {
  font-size: 12px;
  color: var(--muted);
  line-height: 1.7;
  margin-top: auto;
  padding-top: 18px;
}
.mcp-asks {
  list-style: none;
  margin: 0;
  padding: 0;
  display: flex;
  flex-direction: column;
  gap: 12px;
}
.mcp-asks li {
  font-family: var(--font-cn);
  font-size: 14px;
  line-height: 1.6;
  color: var(--label);
  padding-left: 18px;
  position: relative;
}
.mcp-asks li::before {
  content: "";
  position: absolute;
  left: 0;
  top: 9px;
  width: 6px;
  height: 6px;
  border-radius: 50%;
  background: var(--coral);
  opacity: 0.55;
}
.mcp-tools {
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
}
.tool-chip {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  padding: 6px 11px;
  background: #fff;
  border: 0.5px solid var(--hairline);
  border-radius: 999px;
  font-family: var(--font-mono);
  font-size: 11.5px;
  letter-spacing: 0.2px;
  color: var(--label-2);
}
.tool-chip--write::before {
  content: "";
  width: 5px;
  height: 5px;
  border-radius: 50%;
  background: var(--coral);
}
.mcp-guards {
  list-style: none;
  margin: 24px 0 0;
  padding: 0;
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 16px;
  max-width: 900px;
}
.mcp-guards li {
  font-size: 12.5px;
  line-height: 1.7;
  color: var(--muted);
  padding-top: 14px;
  border-top: 0.5px solid var(--hairline);
}
.mcp-guards strong { color: var(--label-2); font-weight: 600; }

/* docs · MCP 工具表 */

.tool-table {
  width: 100%;
  max-width: 680px;
  border-collapse: collapse;
  margin: 0 0 24px;
  font-size: 13px;
}
.tool-table th,
.tool-table td {
  text-align: left;
  padding: 9px 12px 9px 0;
  border-bottom: 0.5px solid var(--hairline-2);
  vertical-align: top;
  line-height: 1.6;
}
.tool-table th {
  font-size: 10px;
  color: var(--muted);
  letter-spacing: 1.2px;
  text-transform: uppercase;
  font-weight: 600;
}
.tool-table td:first-child {
  font-family: var(--font-mono);
  font-size: 12px;
  color: var(--label);
  white-space: nowrap;
  padding-right: 18px;
}
.tool-table td:last-child {
  color: var(--muted);
  white-space: nowrap;
  font-size: 12px;
}
.docs-content h2 {
  font-family: var(--font-cn);
  font-size: 18px;
  font-weight: 600;
  color: var(--label);
  margin: 36px 0 12px;
}
.docs-content ul,
.docs-content ol {
  max-width: 680px;
  padding-left: 20px;
  margin: 0 0 20px;
}
.docs-content li {
  font-size: 14px;
  line-height: 1.85;
  color: var(--text);
  margin-bottom: 6px;
}
.docs-content code {
  background: var(--surface);
  border: 0.5px solid var(--hairline-2);
  padding: 1px 6px;
  border-radius: 3px;
  font-family: var(--font-mono);
  font-size: 12px;
  color: var(--label);
}
.docs-content hr {
  border: none;
  border-top: 0.5px solid var(--hairline-2);
  margin: 48px 0 36px;
  max-width: 680px;
}

/* ── reveal animations ── */

[data-reveal-on-scroll] {
  opacity: 0;
  transform: translateY(36px);
  transition:
    opacity   0.9s var(--ease-out),
    transform 0.9s var(--ease-out);
}
[data-reveal-on-scroll].is-visible {
  opacity: 1;
  transform: translateY(0);
}
/* stagger — 同一父容器内多个子元素错开进入 */
[data-reveal-on-scroll][data-stagger="1"] { transition-delay: 0.08s; }
[data-reveal-on-scroll][data-stagger="2"] { transition-delay: 0.16s; }
[data-reveal-on-scroll][data-stagger="3"] { transition-delay: 0.24s; }

/* hero mark — reveal 起点(JS 启动前) */
.mark--reveal .arc-up,
.mark--reveal .arc-dn {
  stroke-dasharray: 880;
  stroke-dashoffset: 880;
}
.mark--reveal .axis {
  transform-origin: 496px 538px;
  opacity: 0;
  transform: scale(0.3);
}
/* reveal 完成态 · 总时长 ~1.4s,看得见的节奏 */
.mark--reveal.is-revealed .arc-up {
  animation: arc-up 720ms var(--ease-out) 280ms forwards;
}
.mark--reveal.is-revealed .arc-dn {
  animation: arc-dn 720ms var(--ease-out) 560ms forwards;
}
.mark--reveal.is-revealed .axis {
  animation:
    axis-pop 560ms var(--ease-out) forwards,
    axis-pulse 2.4s ease-in-out 1.6s infinite;
}
@keyframes arc-up { to { stroke-dashoffset: 0; } }
@keyframes arc-dn { to { stroke-dashoffset: 0; } }
@keyframes axis-pop {
  0%   { opacity: 0; transform: scale(0.3); }
  60%  { opacity: 1; transform: scale(1.08); }
  100% { opacity: 1; transform: scale(1); }
}

/* hero 完成后, mark 整体微微「呼吸」 — 不改 mark 几何, 只是容器的 0.5% 缩放 */
.hero__mark {
  animation: hero-breathe 5.2s ease-in-out 2.4s infinite;
  transform-origin: center;
}
@keyframes hero-breathe {
  0%, 100% { transform: scale(1); }
  50%      { transform: scale(1.025); }
}

/* processing pulse · 仅作用于 .mark[data-state="processing"] 的轴 */
.mark[data-state="processing"] .axis {
  animation: axis-pulse 1.6s ease-in-out infinite;
  transform-origin: 496px 538px;
}
@keyframes axis-pulse {
  0%, 100% { opacity: 0.5; }
  50%      { opacity: 1; }
}

/* brand page · 用于 motion demo · 永久循环 */
.motion-card__demo .demo-reveal .arc-up {
  stroke-dasharray: 880;
  animation: demo-arc-up 1.6s var(--ease-out) infinite;
}
.motion-card__demo .demo-reveal .arc-dn {
  stroke-dasharray: 880;
  animation: demo-arc-dn 1.6s var(--ease-out) infinite;
}
.motion-card__demo .demo-reveal .axis {
  transform-origin: 496px 538px;
  animation: demo-axis-pop 1.6s var(--ease-out) infinite;
}
@keyframes demo-arc-up {
  0%, 18%  { stroke-dashoffset: 880; }
  60%      { stroke-dashoffset: 0; }
  92%      { stroke-dashoffset: 0; }
  100%     { stroke-dashoffset: 880; }
}
@keyframes demo-arc-dn {
  0%, 30%  { stroke-dashoffset: 880; }
  75%      { stroke-dashoffset: 0; }
  92%      { stroke-dashoffset: 0; }
  100%     { stroke-dashoffset: 880; }
}
@keyframes demo-axis-pop {
  0%       { opacity: 0; transform: scale(0.3); }
  20%      { opacity: 1; transform: scale(1); }
  92%      { opacity: 1; transform: scale(1); }
  100%     { opacity: 0; transform: scale(0.3); }
}
.motion-card__demo .demo-pulse .axis {
  transform-origin: 496px 538px;
  animation: axis-pulse 1.6s ease-in-out infinite;
}

/* ── responsive ── */

@media (max-width: 920px) {
  .footer__inner { grid-template-columns: 1fr 1fr; }
}

@media (max-width: 720px) {
  :root { --pad-x: var(--pad-x-sm); }
  .hero { padding: 48px 0 56px; }
  .hero__inner { grid-template-columns: 1fr; gap: 28px; }
  .hero__mark { order: -1; gap: 18px; }
  .hero__mark svg { width: 200px !important; height: 200px !important; }
  .hero__title { font-size: 38px; }
  .hero__title--en { font-size: 40px; letter-spacing: -1.4px; }
  .section { padding: 56px 0; }
  .section h2 { font-size: 24px; }
  .features { grid-template-columns: 1fr; }
  .features::before, .features::after { display: none; }
  .platform-list { grid-template-columns: 1fr; gap: 14px; }
  .loop { grid-template-columns: 1fr; gap: 28px; }
  .loop__mark { padding: 24px; }
  .flow {
    grid-template-columns: 1fr;
    gap: 18px;
    max-width: 100%;
    justify-items: center;
  }
  .flow__conn {
    width: 1px;
    height: 28px;
    background: linear-gradient(180deg,
      rgba(244, 125, 142, 0) 0%,
      rgba(244, 125, 142, 0.5) 30%,
      rgba(244, 125, 142, 0.5) 70%,
      rgba(244, 125, 142, 0) 100%);
  }
  .flow__conn::after { content: "↓"; top: auto; right: 50%; bottom: -8px; transform: translateX(50%); }
  .colors { grid-template-columns: 1fr; }
  .motion-grid { grid-template-columns: 1fr; }
  .examples { grid-template-columns: repeat(2, 1fr); }
  .mcp-grid { grid-template-columns: 1fr; }
  .mcp-guards { grid-template-columns: 1fr; gap: 12px; }
  .docs-layout { grid-template-columns: 1fr; }
  .docs-sidebar { border-right: none; border-bottom: 0.5px solid var(--hairline-2); }
  .docs-content { padding: 32px 24px 48px; }
  .nav__links { display: none; }
  .footer__inner { grid-template-columns: 1fr; gap: 28px; }
  .brand-page h1 { font-size: 26px; }
}

/* ── reduced motion ── */

@media (prefers-reduced-motion: reduce) {
  *, *::before, *::after {
    animation-duration: 0.001ms !important;
    animation-iteration-count: 1 !important;
    transition-duration: 0.001ms !important;
  }
  [data-reveal-on-scroll] { opacity: 1; transform: none; }
  .mark--reveal .arc-up,
  .mark--reveal .arc-dn { stroke-dashoffset: 0; }
  .mark--reveal .axis { opacity: 1; transform: none; }
}