/* =========================================================
   Amplify Signal System · 2026-08
   证据优先的白底分析型设计系统。此文件作为 v2 覆盖层，保留旧页面语义。
   ========================================================= */

:root {
  --am-purple: #57318c;
  --am-purple-strong: #45226f;
  --am-purple-soft: #eee8f6;
  --am-violet: #8d6abd;
  --am-blue: #315cf5;
  --am-ink: #111216;
  --am-ink-2: #353840;
  --am-muted: #696d76;
  --am-line: #dfe1e6;
  --am-line-strong: #b7bac2;
  --am-paper: #ffffff;
  --am-surface: #f7f7f8;
  --am-surface-purple: #f7f4fb;
  --am-wrap: 1360px;
  --am-display: -apple-system, BlinkMacSystemFont, "SF Pro Display", "PingFang SC", "Noto Sans SC", "Microsoft YaHei", sans-serif;
  --am-mono: "SFMono-Regular", "SF Mono", "JetBrains Mono", Menlo, Consolas, monospace;

  --paper: var(--am-paper);
  --surface: var(--am-paper);
  --surface-2: var(--am-surface);
  --ink: var(--am-ink);
  --ink-2: var(--am-ink-2);
  --muted: var(--am-muted);
  --line: var(--am-line);
  --plum: var(--am-ink);
  --plum-deep: var(--am-ink);
  --violet: var(--am-purple);
  --violet-dark: var(--am-purple-strong);
  --violet-soft: var(--am-purple-soft);
  --tint: #c9b7df;
  --display: var(--am-display);
  --editorial: var(--am-display);
  --mono: var(--am-mono);
  --wrap: var(--am-wrap);
  --wrap-narrow: 820px;
  --r: 0;
}

html {
  scroll-padding-top: 82px;
}

body {
  overflow-x: hidden;
  background: var(--am-paper);
  color: var(--am-ink);
  font-family: var(--am-display);
  font-size: 16px;
  line-height: 1.72;
}

body::before {
  content: "";
  position: fixed;
  z-index: 9999;
  inset: 0 0 auto;
  height: 3px;
  background: var(--am-purple);
  pointer-events: none;
}

.skip-link {
  position: fixed;
  z-index: 10001;
  top: 10px;
  left: 12px;
  padding: 10px 14px;
  background: var(--am-ink);
  color: #fff;
  transform: translateY(-160%);
}

.skip-link:focus {
  color: #fff;
  transform: translateY(0);
}

::selection {
  background: #d8cbea;
  color: var(--am-ink);
}

a {
  color: var(--am-purple);
}

a:hover {
  color: var(--am-purple-strong);
}

h1,
h2,
h3,
h4 {
  color: var(--am-ink);
  font-family: var(--am-display);
  font-weight: 760;
  letter-spacing: -0.035em;
}

h1 {
  font-size: clamp(44px, 5.7vw, 78px);
  line-height: 1.08;
}

h2 {
  font-size: clamp(30px, 3.4vw, 48px);
  line-height: 1.15;
}

h3 {
  font-size: 21px;
  line-height: 1.35;
}

p,
li,
td,
th,
input,
textarea,
select,
button {
  font-family: var(--am-display);
}

.wrap {
  width: min(calc(100% - 80px), var(--am-wrap));
  margin-inline: auto;
  padding: 0;
}

.wrap-narrow {
  width: min(calc(100% - 64px), 820px);
  padding: 0;
}

section {
  padding: clamp(72px, 7vw, 112px) 0;
}

section + section,
.page-hero + section,
.tight + section {
  border-top: 1px solid var(--am-line);
}

.muted,
.lede,
.card p,
.tool-card p,
.step p {
  color: var(--am-muted);
}

.eyebrow,
.editorial-label,
.signal-label {
  color: var(--am-purple);
  font: 700 11px/1.3 var(--am-mono);
  letter-spacing: 0.12em;
  text-transform: uppercase;
}

/* ---------- 全站导航 ---------- */
.nav {
  position: sticky;
  top: 0;
  z-index: 1000;
  border-bottom: 1px solid var(--am-line);
  background: rgba(255, 255, 255, 0.96);
  backdrop-filter: blur(16px);
}

.nav.scrolled {
  box-shadow: 0 8px 28px rgba(17, 18, 22, 0.05);
}

.nav-inner {
  height: 80px;
}

.brand,
.brand:hover {
  color: var(--am-ink);
}

.brand {
  gap: 12px;
}

.brand-mark {
  width: 38px;
  height: 36px;
  object-fit: contain;
  image-rendering: auto;
}

.brand > span {
  font-family: var(--am-display);
  font-size: 21px;
  font-weight: 780;
  letter-spacing: -0.035em;
}

.brand small {
  margin-top: 1px;
  color: var(--am-ink-2);
  font: 500 10px/1.2 var(--am-display);
  letter-spacing: 0.02em;
}

.nav-links {
  gap: 30px;
}

.nav-links a {
  padding: 30px 0 25px;
  border-bottom: 2px solid transparent;
  color: var(--am-ink);
  font-size: 14px;
  font-weight: 640;
  letter-spacing: 0;
}

.nav-links a:hover,
.nav-links a.active {
  border-bottom-color: var(--am-purple);
  color: var(--am-purple);
}

.nav-links .nav-mobile-action {
  display: none;
}

.nav-cta .btn {
  min-height: 46px;
  padding: 11px 19px;
}

.nav-toggle {
  min-width: 48px;
  min-height: 44px;
  border: 1px solid var(--am-ink);
  background: var(--am-paper);
  color: var(--am-ink);
  font-size: 14px;
}

/* ---------- 控件与通用组件 ---------- */
.btn,
button.btn {
  min-height: 52px;
  padding: 14px 24px;
  border: 1px solid var(--am-purple);
  border-radius: 0;
  background: var(--am-purple);
  color: #fff;
  font-size: 14px;
  font-weight: 720;
  letter-spacing: 0;
  box-shadow: none;
  transition: background 160ms ease, border-color 160ms ease, color 160ms ease, transform 160ms ease;
}

.btn:hover,
button.btn:hover {
  border-color: var(--am-ink);
  background: var(--am-ink);
  color: #fff;
  transform: translateY(-2px);
}

.btn:focus-visible,
button:focus-visible,
a:focus-visible,
summary:focus-visible,
input:focus-visible,
textarea:focus-visible,
select:focus-visible {
  outline: 3px solid rgba(87, 49, 140, 0.28);
  outline-offset: 3px;
}

.btn.ghost,
.hero .btn.ghost,
.page-hero .btn.ghost,
.cta-band .btn.ghost,
section.dark .btn.ghost,
.nav .btn.ghost {
  border-color: var(--am-line-strong);
  background: transparent;
  color: var(--am-ink);
}

.btn.ghost:hover,
.hero .btn.ghost:hover,
.page-hero .btn.ghost:hover,
.cta-band .btn.ghost:hover,
section.dark .btn.ghost:hover,
.nav .btn.ghost:hover {
  border-color: var(--am-purple);
  background: var(--am-purple-soft);
  color: var(--am-purple-strong);
}

.btn.light {
  border-color: #fff;
  background: #fff;
  color: var(--am-ink);
}

.btn.light:hover {
  border-color: #fff;
  background: var(--am-purple-soft);
  color: var(--am-purple-strong);
}

.btn.sm {
  min-height: 44px;
  padding: 10px 18px;
}

.grid {
  gap: 1px;
  border: 1px solid var(--am-line);
  background: var(--am-line);
}

.grid > * {
  background: var(--am-paper);
}

.card,
.card-flat,
.tool-card,
.tool-panel,
.tool-aside {
  border: 0;
  border-radius: 0;
  background: var(--am-paper);
  box-shadow: none;
}

.card,
.tool-card {
  padding: 30px;
}

.card.hover:hover,
.tool-card:hover {
  border-color: transparent;
  background: var(--am-surface-purple);
  box-shadow: inset 0 3px 0 var(--am-purple);
  transform: none;
}

.card h3,
.tool-card h3,
.card-flat h3,
.card-flat h4 {
  color: var(--am-ink);
}

.card-num,
.tool-card .go,
.tool-card .ico {
  color: var(--am-purple);
}

.badge {
  border-color: currentColor;
  border-radius: 0;
  background: transparent;
  color: var(--am-purple);
  font-weight: 700;
}

.callout,
.page-hero .callout {
  border: 0;
  border-left: 4px solid var(--am-purple);
  background: var(--am-surface-purple);
  color: var(--am-ink-2);
}

.faq details {
  border: 0;
  border-top: 1px solid var(--am-line);
  border-radius: 0;
  background: transparent;
}

.faq details:last-child {
  border-bottom: 1px solid var(--am-line);
}

.faq summary {
  min-height: 64px;
  padding: 20px 48px 20px 0;
  color: var(--am-ink);
  font-family: var(--am-display);
  font-size: 18px;
  font-weight: 700;
}

.faq summary::after {
  color: var(--am-purple);
}

.faq details p {
  max-width: 70ch;
  padding: 0 0 24px;
  color: var(--am-muted);
}

/* ---------- 内页基座 ---------- */
.page-hero {
  padding: clamp(72px, 8vw, 116px) 0;
  border-bottom: 1px solid var(--am-line);
  background: var(--am-paper);
  color: var(--am-ink);
}

.page-hero::after {
  display: none;
}

.page-hero .wrap {
  max-width: var(--am-wrap);
}

.page-hero h1,
.page-hero .lede,
.page-hero .lede strong {
  color: var(--am-ink);
}

.page-hero h1 {
  max-width: 18ch;
  font-size: clamp(42px, 5.2vw, 72px);
}

.page-hero .lede {
  max-width: 68ch;
  font-size: clamp(17px, 1.5vw, 20px);
}

.os-hero-meta {
  border-top-color: var(--am-line);
}

.os-hero-meta div {
  padding-top: 18px;
}

.os-hero-meta span {
  color: var(--am-muted);
}

.os-hero-meta strong {
  color: var(--am-ink);
}

.page-hero .eyebrow,
.crumb,
.crumb a {
  color: var(--am-purple);
}

.section-head {
  max-width: 800px;
  margin-bottom: 48px;
}

.section-head h2 {
  margin-top: 10px;
}

.section-head .lede {
  max-width: 66ch;
  margin-top: 16px;
}

/* ---------- Praxeon 公开运行实例 ---------- */
.os-praxeon-section {
  background: var(--am-surface);
}

.os-praxeon-grid {
  display: grid;
  grid-template-columns: minmax(280px, 0.78fr) minmax(0, 1.22fr);
  gap: 1px;
  border: 1px solid var(--am-line);
  background: var(--am-line);
}

.os-praxeon-profile,
.os-praxeon-ops {
  min-width: 0;
  padding: clamp(24px, 3vw, 36px);
  background: var(--am-paper);
}

.os-praxeon-profile-head,
.os-praxeon-ops-head {
  display: flex;
  align-items: flex-start;
  justify-content: space-between;
  gap: 18px;
}

.os-praxeon-status {
  display: flex;
  align-items: center;
  gap: 7px;
  color: var(--am-muted);
  font: 700 10px/1.3 var(--am-mono);
  letter-spacing: 0.08em;
}

.os-praxeon-status i {
  width: 7px;
  height: 7px;
  border-radius: 50%;
  background: var(--am-purple);
}

.os-praxeon-profile h3 {
  margin-top: 16px;
  font-size: 30px;
}

.os-praxeon-profile-head a {
  display: inline-block;
  margin-top: 2px;
  font: 500 13px/1.4 var(--am-mono);
}

.os-praxeon-mark {
  display: grid;
  width: 48px;
  height: 48px;
  place-items: center;
  border: 1px solid var(--am-line-strong);
  color: var(--am-purple);
  font: 700 13px/1 var(--am-mono);
}

.os-praxeon-bio {
  margin-top: 26px;
  color: var(--am-ink-2);
  font-size: 15px;
  line-height: 1.7;
}

.os-praxeon-facts {
  margin: 28px 0 0;
  border-top: 1px solid var(--am-line);
}

.os-praxeon-facts div {
  display: grid;
  grid-template-columns: 72px minmax(0, 1fr);
  gap: 16px;
  padding: 12px 0;
  border-bottom: 1px solid var(--am-line);
}

.os-praxeon-facts dt {
  color: var(--am-muted);
  font-size: 12px;
}

.os-praxeon-facts dd {
  min-width: 0;
  margin: 0;
  color: var(--am-ink-2);
  font-size: 13px;
  overflow-wrap: anywhere;
}

.os-praxeon-ops-head {
  padding-bottom: 20px;
  border-bottom: 2px solid var(--am-ink);
}

.os-praxeon-ops-head .eyebrow {
  margin-bottom: 8px;
}

.os-praxeon-ops h3 {
  max-width: 21ch;
  font-size: 24px;
}

.os-praxeon-frequency {
  flex: none;
  color: var(--am-purple);
  font: 700 10px/1.55 var(--am-mono);
  text-align: right;
  white-space: nowrap;
}

.os-praxeon-frequency b {
  color: var(--am-muted);
  font-weight: 500;
}

.os-praxeon-pillars {
  display: grid;
  grid-template-columns: repeat(5, minmax(0, 1fr));
  margin-top: 24px;
}

.os-praxeon-pillars > div {
  min-width: 0;
  min-height: 150px;
  padding: 0 15px;
  border-left: 1px solid var(--am-line);
}

.os-praxeon-pillars > div:first-child {
  padding-left: 0;
  border-left: 0;
}

.os-praxeon-pillars b,
.os-praxeon-pillars strong,
.os-praxeon-pillars span {
  display: block;
}

.os-praxeon-pillars b {
  color: var(--am-purple);
  font: 700 18px/1 var(--am-mono);
}

.os-praxeon-pillars strong {
  margin-top: 22px;
  color: var(--am-ink);
  font: 700 11px/1.3 var(--am-mono);
  overflow-wrap: anywhere;
}

.os-praxeon-pillars span {
  margin-top: 8px;
  color: var(--am-muted);
  font-size: 12px;
  line-height: 1.5;
}

.os-praxeon-workflow {
  display: grid;
  grid-template-columns: minmax(220px, 0.72fr) minmax(0, 1.28fr);
  gap: clamp(24px, 5vw, 76px);
  margin-top: 1px;
  padding: 28px clamp(24px, 3vw, 36px);
  border: 1px solid var(--am-line);
  background: var(--am-paper);
}

.os-praxeon-workflow .eyebrow {
  margin-bottom: 8px;
}

.os-praxeon-workflow h3 {
  font-size: 20px;
}

.os-praxeon-workflow p {
  max-width: 68ch;
  color: var(--am-muted);
  font-size: 14px;
}

.os-praxeon-workflow strong {
  color: var(--am-ink-2);
}

.split {
  gap: clamp(40px, 6vw, 96px);
}

.steps {
  border-top: 2px solid var(--am-ink);
}

.step {
  border-color: var(--am-line);
}

.step::before,
.os-principle b,
.os-objective-tree li > span,
.os-responsibility > div > span {
  color: var(--am-purple);
}

table {
  border-color: var(--am-ink);
  background: var(--am-paper);
}

th {
  background: var(--am-surface);
  color: var(--am-ink);
}

th,
td {
  border-color: var(--am-line);
}

tbody tr:hover td {
  background: var(--am-surface-purple);
}

.tool-shell {
  gap: 1px;
  border: 1px solid var(--am-line);
  background: var(--am-line);
}

.tool-panel,
.tool-aside {
  background: var(--am-paper);
}

input,
textarea,
select {
  min-height: 48px;
  border: 1px solid var(--am-line-strong);
  border-radius: 0;
  background: var(--am-paper);
  color: var(--am-ink);
}

input:hover,
textarea:hover,
select:hover {
  border-color: var(--am-purple);
}

.cta-band,
section.dark,
.editorial-constitution,
.os-cta {
  background: var(--am-ink);
  color: rgba(255, 255, 255, 0.72);
}

.cta-band h2,
section.dark h2,
section.dark h3,
section.dark h4,
.editorial-constitution h2,
.os-cta h2 {
  color: #fff;
}

section.dark .card {
  border: 1px solid rgba(255, 255, 255, 0.18);
  background: transparent;
}

/* ---------- 新首页 ---------- */
.signal-hero {
  min-height: 830px;
  padding: clamp(72px, 7.5vw, 118px) 0 82px;
  border: 0;
  background: var(--am-paper);
}

.signal-hero__grid {
  display: grid;
  grid-template-columns: minmax(0, 0.98fr) minmax(460px, 0.92fr);
  gap: clamp(30px, 4.5vw, 72px);
  align-items: center;
}

.signal-status {
  display: inline-flex;
  align-items: center;
  gap: 10px;
  margin: 0 0 30px;
  padding: 7px 13px;
  border: 1px solid var(--am-line);
  border-radius: 999px;
  color: var(--am-ink-2);
  font-size: 13px;
  font-weight: 620;
}

.signal-status span {
  width: 8px;
  height: 8px;
  border-radius: 50%;
  background: var(--am-purple);
  box-shadow: 0 0 0 4px var(--am-purple-soft);
}

.signal-hero h1 {
  max-width: 760px;
  font-size: clamp(48px, 5.25vw, 74px);
  font-weight: 820;
  line-height: 1.08;
  letter-spacing: -0.055em;
}

.signal-hero h1 em {
  color: var(--am-ink);
  font-style: normal;
  white-space: nowrap;
}

.signal-hero h1 em::after {
  content: "";
  display: inline-block;
  width: 14px;
  height: 14px;
  margin-left: 7px;
  border: 4px solid var(--am-purple);
  border-radius: 50%;
  vertical-align: 0.12em;
}

.signal-deck {
  max-width: 650px;
  margin: 30px 0 0;
  color: var(--am-ink-2);
  font-size: clamp(17px, 1.45vw, 20px);
  line-height: 1.7;
}

.signal-actions {
  margin-top: 34px;
}

.signal-proof {
  display: grid;
  grid-template-columns: 1.25fr repeat(4, 1fr);
  margin-top: 42px;
  padding-top: 24px;
  border-top: 1px solid var(--am-line);
}

.signal-proof > div {
  min-height: 78px;
  padding: 0 18px;
  border-left: 1px solid var(--am-line);
}

.signal-proof > div:first-child {
  padding-left: 0;
  border-left: 0;
}

.signal-proof__label span,
.signal-proof__label strong {
  display: block;
}

.signal-proof__label span {
  color: var(--am-ink);
  font-size: 13px;
  font-weight: 720;
}

.signal-proof__label strong {
  margin-top: 5px;
  color: var(--am-muted);
  font-size: 12px;
  font-weight: 550;
}

.signal-proof > div:not(:first-child) strong {
  display: block;
  color: var(--am-ink);
  font-size: 28px;
  line-height: 1;
}

.signal-proof > div:not(:first-child) span {
  display: block;
  margin-top: 8px;
  color: var(--am-muted);
  font-size: 11px;
  line-height: 1.45;
}

.signal-caveat {
  margin: 18px 0 0;
  color: var(--am-muted);
  font-size: 11px;
}

.signal-hero__visual {
  position: relative;
  min-height: 600px;
  margin: 0;
}

.signal-hero__visual img {
  position: absolute;
  inset: 0 -7% 0 -10%;
  width: 117%;
  height: 100%;
  object-fit: cover;
  object-position: 43% center;
  mix-blend-mode: multiply;
}

.signal-note {
  position: absolute;
  z-index: 1;
  display: grid;
  min-width: 140px;
  gap: 3px;
  padding-bottom: 8px;
  border-bottom: 1px solid var(--am-line-strong);
  color: var(--am-ink);
  font-size: 11px;
  line-height: 1.35;
}

.signal-note::before {
  content: "";
  position: absolute;
  bottom: -4px;
  left: 0;
  width: 7px;
  height: 7px;
  border-radius: 50%;
  background: var(--am-purple);
}

.signal-note span {
  color: var(--am-muted);
}

.signal-note--top {
  top: 10%;
  left: 4%;
}

.signal-note--middle {
  top: 41%;
  left: 0;
}

.signal-note--bottom {
  right: 4%;
  bottom: 17%;
}

.signal-capabilities {
  background: var(--am-paper);
}

.signal-section-head {
  max-width: 780px;
  margin-bottom: 54px;
}

.signal-section-head.center {
  margin-inline: auto;
  text-align: center;
}

.signal-section-head > span {
  color: var(--am-purple);
  font: 700 11px/1.3 var(--am-mono);
  letter-spacing: 0.13em;
}

.signal-section-head h2 {
  margin-top: 12px;
}

.signal-section-head p {
  margin-top: 14px;
  color: var(--am-muted);
}

.signal-capability-grid {
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  border-top: 1px solid var(--am-line);
  border-bottom: 1px solid var(--am-line);
}

.signal-capability {
  display: flex;
  flex-direction: column;
  min-width: 0;
  padding: 30px 38px 34px;
  border-left: 1px solid var(--am-line);
}

.signal-capability:first-child {
  border-left: 0;
}

.signal-capability__title {
  display: flex;
  align-items: flex-start;
  gap: 12px;
}

.signal-capability__title b {
  flex: 0 0 auto;
  padding: 4px 6px;
  background: var(--am-purple);
  color: #fff;
  font: 700 11px/1 var(--am-mono);
}

.signal-capability__title h3 {
  font-size: 18px;
}

.signal-capability > p {
  min-height: 76px;
  margin: 18px 0 0;
  color: var(--am-muted);
  font-size: 14px;
}

.signal-capability > img {
  width: 100%;
  height: 210px;
  margin: 22px 0 12px;
  object-fit: cover;
}

.signal-capability ul {
  margin: 0;
  padding: 0;
  list-style: none;
}

.signal-capability li {
  position: relative;
  padding-left: 14px;
  color: var(--am-ink-2);
  font-size: 13px;
}

.signal-capability li::before {
  content: "";
  position: absolute;
  top: 0.75em;
  left: 0;
  width: 4px;
  height: 4px;
  border-radius: 50%;
  background: var(--am-purple);
}

.signal-capability > a {
  margin-top: auto;
  padding-top: 22px;
  color: var(--am-purple);
  font-size: 13px;
  font-weight: 700;
}

.signal-case {
  background: var(--am-surface);
}

.signal-case__grid {
  display: grid;
  grid-template-columns: 0.95fr 1.35fr;
  gap: clamp(48px, 7vw, 104px);
  align-items: center;
}

.signal-case__copy h2 {
  margin: 10px 0 20px;
}

.signal-case__copy > p {
  max-width: 58ch;
  color: var(--am-muted);
}

.signal-case dl {
  margin: 30px 0 0;
  border-top: 1px solid var(--am-line-strong);
}

.signal-case dl div {
  display: grid;
  grid-template-columns: 86px 1fr;
  gap: 18px;
  padding: 11px 0;
  border-bottom: 1px solid var(--am-line);
  font-size: 13px;
}

.signal-case dt {
  color: var(--am-ink);
  font-weight: 720;
}

.signal-case dd {
  margin: 0;
  color: var(--am-muted);
}

.signal-link {
  display: inline-flex;
  gap: 10px;
  margin-top: 28px;
  padding-bottom: 3px;
  border-bottom: 1px solid var(--am-purple);
  color: var(--am-purple);
  font-size: 14px;
  font-weight: 720;
}

.signal-case__chart {
  min-height: 470px;
  padding: 30px;
  border: 1px solid var(--am-line);
  background: var(--am-paper);
}

.signal-case__chart img {
  width: 100%;
  height: 350px;
  object-fit: cover;
  object-position: center;
  mix-blend-mode: multiply;
}

.signal-case__chart > p {
  margin: 8px 0 0;
  color: var(--am-muted);
  font-size: 11px;
  text-align: right;
}

.signal-case__legend {
  display: flex;
  gap: 22px;
  margin-bottom: 16px;
  color: var(--am-muted);
  font-size: 11px;
}

.signal-case__legend span {
  display: inline-flex;
  align-items: center;
  gap: 7px;
}

.signal-case__legend i {
  width: 7px;
  height: 7px;
  border-radius: 50%;
  background: var(--am-purple);
}

.signal-case__legend span + span i {
  background: var(--am-blue);
}

.signal-method {
  background: var(--am-ink);
  color: rgba(255, 255, 255, 0.74);
}

.signal-method__grid {
  display: grid;
  grid-template-columns: 0.85fr 1.15fr;
  gap: clamp(42px, 7vw, 110px);
  align-items: center;
}

.signal-method h2 {
  margin-top: 10px;
  color: #fff;
}

.signal-method p {
  max-width: 62ch;
  font-size: 18px;
}

.signal-method .btn-row {
  margin-top: 28px;
}

.signal-method .btn.ghost {
  border-color: rgba(255, 255, 255, 0.38);
  color: #fff;
}

.signal-method .btn.ghost:hover {
  border-color: #fff;
  background: #fff;
  color: var(--am-ink);
}

.signal-tools {
  background: var(--am-paper);
}

.signal-tool-list {
  border-top: 2px solid var(--am-ink);
}

.signal-tool-list a {
  display: grid;
  grid-template-columns: 62px 1.1fr 1.4fr auto;
  gap: 24px;
  align-items: center;
  min-height: 86px;
  padding: 16px 0;
  border-bottom: 1px solid var(--am-line);
  color: var(--am-ink);
}

.signal-tool-list a:hover {
  padding-inline: 16px;
  background: var(--am-surface-purple);
}

.signal-tool-list b {
  color: var(--am-purple);
  font: 700 12px var(--am-mono);
}

.signal-tool-list strong {
  font-size: 18px;
}

.signal-tool-list span {
  color: var(--am-muted);
  font-size: 14px;
}

.signal-tool-list em {
  color: var(--am-purple);
  font-size: 13px;
  font-style: normal;
  font-weight: 700;
}

.signal-faq {
  background: var(--am-surface);
}

/* ---------- 页脚 ---------- */
.foot {
  padding: 70px 0 32px;
  border-top: 1px solid var(--am-line);
  background: var(--am-paper);
  color: var(--am-muted);
}

.foot-grid {
  grid-template-columns: 1.45fr repeat(4, 0.75fr);
  gap: 42px;
}

.foot h4,
.foot .brand,
.foot .brand:hover {
  color: var(--am-ink);
}

.foot h4 {
  padding-bottom: 12px;
  border-bottom: 1px solid var(--am-line);
  font-size: 13px;
}

.foot a,
.foot-brand p,
.foot-bottom {
  color: var(--am-muted);
}

.foot a:hover {
  color: var(--am-purple);
}

.foot-bottom {
  border-top-color: var(--am-line);
}

/* ---------- 响应式 ---------- */
@media (max-width: 1080px) {
  .signal-hero__grid {
    grid-template-columns: 1fr 0.85fr;
  }

  .signal-proof {
    grid-template-columns: repeat(4, 1fr);
  }

  .signal-proof__label {
    grid-column: 1 / -1;
    min-height: auto !important;
    padding: 0 0 15px !important;
    border: 0 !important;
  }

  .signal-capability {
    padding-inline: 24px;
  }

  .foot-grid {
    grid-template-columns: 1.5fr repeat(2, 1fr);
  }
}

@media (max-width: 900px) {
  body.nav-open {
    overflow: hidden;
  }

  .wrap,
  .wrap-narrow {
    width: min(calc(100% - 40px), var(--am-wrap));
  }

  .nav-links {
    position: absolute;
    top: 80px;
    right: 0;
    left: 0;
    display: none;
    min-height: calc(100vh - 80px);
    overflow-y: auto;
    padding: 8px 20px 18px;
    border-bottom: 1px solid var(--am-ink);
    background: var(--am-paper);
  }

  .nav-links.open {
    display: grid;
  }

  .nav-links a {
    min-height: 52px;
    padding: 16px 0 12px;
    border-bottom: 1px solid var(--am-line);
  }

  .nav-links a:last-child {
    border-bottom: 0;
  }

  .nav-links .nav-mobile-action {
    display: flex;
    align-items: center;
    justify-content: center;
    margin-top: 10px;
    border: 1px solid var(--am-purple);
    background: var(--am-purple);
    color: #fff;
  }

  .nav-cta .btn {
    display: none;
  }

  .nav-toggle {
    display: inline-flex;
    align-items: center;
    justify-content: center;
  }

  .signal-hero__grid,
  .signal-case__grid,
  .signal-method__grid {
    grid-template-columns: 1fr;
  }

  .signal-hero {
    padding-bottom: 40px;
  }

  .signal-hero__visual {
    order: -1;
    min-height: 380px;
  }

  .signal-note--top {
    top: 8%;
  }

  .signal-capability-grid {
    grid-template-columns: 1fr;
  }

  .signal-capability {
    padding: 32px 0;
    border-top: 1px solid var(--am-line);
    border-left: 0;
  }

  .signal-capability:first-child {
    border-top: 0;
  }

  .signal-capability > p {
    min-height: 0;
  }

  .signal-capability > img {
    height: 260px;
    object-fit: contain;
  }

  .signal-case__chart {
    min-height: 0;
  }

  .signal-tool-list a {
    grid-template-columns: 42px 1fr auto;
  }

  .signal-tool-list span {
    grid-column: 2 / -1;
  }

  .os-praxeon-grid,
  .os-praxeon-workflow {
    grid-template-columns: 1fr;
  }

  .os-praxeon-pillars {
    grid-template-columns: repeat(3, minmax(0, 1fr));
    row-gap: 28px;
  }

  .os-praxeon-pillars > div:nth-child(4) {
    padding-left: 0;
    border-left: 0;
  }
}

@media (max-width: 640px) {
  body::before {
    height: 2px;
  }

  .wrap,
  .wrap-narrow {
    width: min(calc(100% - 32px), var(--am-wrap));
  }

  section {
    padding: 64px 0;
  }

  .nav-inner {
    height: 72px;
  }

  .nav-links {
    top: 72px;
    min-height: calc(100vh - 72px);
  }

  .brand-mark {
    width: 34px;
    height: 32px;
  }

  .brand > span {
    font-size: 19px;
  }

  .brand small {
    display: none;
  }

  .signal-hero {
    min-height: 0;
    padding-top: 54px;
  }

  .signal-hero__visual {
    display: none;
  }

  .signal-status {
    margin-bottom: 22px;
    font-size: 11px;
  }

  .signal-hero h1 {
    font-size: clamp(42px, 12.6vw, 58px);
    line-height: 1.08;
    letter-spacing: -0.06em;
  }

  .signal-hero h1 br {
    display: none;
  }

  .signal-hero h1 em {
    white-space: normal;
  }

  .signal-hero h1 em::after {
    width: 11px;
    height: 11px;
    border-width: 3px;
  }

  .signal-deck {
    margin-top: 24px;
    font-size: 16px;
  }

  .signal-actions {
    display: grid;
    grid-template-columns: 1fr;
  }

  .signal-actions .btn {
    width: 100%;
  }

  .signal-proof {
    grid-template-columns: repeat(2, 1fr);
    row-gap: 24px;
  }

  .signal-proof > div {
    padding-left: 16px;
  }

  .signal-proof > div:nth-child(2),
  .signal-proof > div:nth-child(4) {
    padding-left: 0;
    border-left: 0;
  }

  .signal-section-head.center {
    text-align: left;
  }

  .signal-section-head h2 {
    font-size: 34px;
  }

  .signal-capability > img {
    height: 210px;
  }

  .signal-case dl div {
    grid-template-columns: 1fr;
    gap: 3px;
  }

  .signal-case__chart {
    padding: 16px;
  }

  .signal-case__chart img {
    height: 260px;
  }

  .signal-method p {
    font-size: 16px;
  }

  .signal-method .btn-row {
    display: grid;
  }

  .signal-tool-list a {
    grid-template-columns: 32px 1fr;
    gap: 8px 14px;
    padding: 18px 0;
  }

  .signal-tool-list span,
  .signal-tool-list em {
    grid-column: 2;
  }

  .signal-tool-list strong {
    font-size: 16px;
  }

  .foot-grid {
    grid-template-columns: 1fr 1fr;
  }

  .foot-brand {
    grid-column: 1 / -1;
  }

  .foot-bottom {
    display: grid;
    gap: 8px;
  }

  .os-hero-meta,
  .os-responsibility,
  .os-objective-tree li {
    grid-template-columns: 1fr;
  }

  .os-responsibility > div + div {
    padding-left: 0;
    border-top: 1px solid var(--am-line);
    border-left: 0;
  }

  .os-praxeon-profile,
  .os-praxeon-ops {
    padding: 24px 20px;
  }

  .os-praxeon-ops-head {
    display: block;
  }

  .os-praxeon-frequency {
    display: block;
    margin-top: 14px;
    text-align: left;
  }

  .os-praxeon-pillars {
    grid-template-columns: repeat(2, minmax(0, 1fr));
  }

  .os-praxeon-pillars > div,
  .os-praxeon-pillars > div:nth-child(4) {
    padding: 0 14px;
    border-left: 1px solid var(--am-line);
  }

  .os-praxeon-pillars > div:nth-child(odd) {
    padding-left: 0;
    border-left: 0;
  }

  .os-praxeon-pillars > div:nth-child(5) {
    grid-column: 1 / -1;
    padding-top: 24px;
    border-top: 1px solid var(--am-line);
  }

  .os-praxeon-workflow {
    padding: 24px 20px;
  }
}

@media (prefers-reduced-motion: reduce) {
  *,
  *::before,
  *::after {
    scroll-behavior: auto !important;
    transition-duration: 0.01ms !important;
    animation-duration: 0.01ms !important;
    animation-iteration-count: 1 !important;
  }
}