/* 杭州东汜科技 — 简约响应式官网 */

:root {
  --color-bg: #fafaf9;
  --color-surface: #ffffff;
  --color-text: #1c1917;
  --color-text-muted: #57534e;
  --color-border: #e7e5e4;
  --color-accent: #0f766e;
  --color-accent-hover: #0d9488;
  --color-hero-tint: #ccfbf1;
  --font-sans: "Noto Sans SC", "DM Sans", system-ui, -apple-system, "Segoe UI", sans-serif;
  --font-mono: ui-monospace, "Cascadia Code", monospace;
  --radius: 12px;
  --shadow: 0 1px 2px rgba(28, 25, 23, 0.06), 0 8px 24px rgba(28, 25, 23, 0.06);
  --header-h: 64px;
  --space-section: clamp(4rem, 8vw, 6.5rem);
  --container: min(1120px, calc(100% - 2rem));
}

*,
*::before,
*::after {
  box-sizing: border-box;
}

html {
  scroll-behavior: smooth;
}

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

body {
  margin: 0;
  font-family: var(--font-sans);
  font-size: 1rem;
  line-height: 1.65;
  color: var(--color-text);
  background: var(--color-bg);
  -webkit-font-smoothing: antialiased;
}

img {
  max-width: 100%;
  height: auto;
}

a {
  color: var(--color-accent);
  text-decoration-thickness: 1px;
  text-underline-offset: 3px;
}

a:hover {
  color: var(--color-accent-hover);
}

.skip-link {
  position: absolute;
  left: -9999px;
  top: auto;
  width: 1px;
  height: 1px;
  overflow: hidden;
}

.skip-link:focus {
  left: 1rem;
  top: 1rem;
  width: auto;
  height: auto;
  padding: 0.5rem 1rem;
  background: var(--color-surface);
  border: 1px solid var(--color-border);
  border-radius: var(--radius);
  z-index: 1000;
}

.container {
  width: var(--container);
  margin-inline: auto;
}

/* Header */
.site-header {
  position: sticky;
  top: 0;
  z-index: 100;
  background: rgba(250, 250, 249, 0.88);
  backdrop-filter: blur(10px);
  border-bottom: 1px solid transparent;
  transition: border-color 0.2s ease;
}

.site-header.is-scrolled {
  border-color: var(--color-border);
}

.header-inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  min-height: var(--header-h);
  gap: 1rem;
}

.logo {
  display: flex;
  align-items: center;
  gap: 0.65rem;
  text-decoration: none;
  color: inherit;
}

.logo-mark {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  width: 2.25rem;
  height: 2.25rem;
  border-radius: 10px;
  background: var(--color-text);
  color: var(--color-bg);
  font-weight: 700;
  font-size: 0.8rem;
  letter-spacing: 0.04em;
}

.logo-text {
  font-weight: 600;
  font-size: clamp(0.85rem, 2.5vw, 0.95rem);
  line-height: 1.25;
  max-width: 14rem;
}

.nav-toggle {
  display: none;
  flex-direction: column;
  justify-content: center;
  gap: 6px;
  width: 2.75rem;
  height: 2.75rem;
  padding: 0;
  border: none;
  background: transparent;
  cursor: pointer;
  border-radius: var(--radius);
}

.nav-toggle:focus-visible {
  outline: 2px solid var(--color-accent);
  outline-offset: 2px;
}

.nav-toggle-bar {
  display: block;
  width: 1.35rem;
  height: 2px;
  background: var(--color-text);
  margin-inline: auto;
  transition: transform 0.2s ease, opacity 0.2s ease;
}

.nav-toggle[aria-expanded="true"] .nav-toggle-bar:first-child {
  transform: translateY(4px) rotate(45deg);
}

.nav-toggle[aria-expanded="true"] .nav-toggle-bar:last-child {
  transform: translateY(-4px) rotate(-45deg);
}

.site-nav .nav-list {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 0.25rem 1.5rem;
  list-style: none;
  margin: 0;
  padding: 0;
}

.site-nav a {
  color: var(--color-text-muted);
  text-decoration: none;
  font-weight: 500;
  font-size: 0.9375rem;
  padding: 0.35rem 0;
  border-bottom: 2px solid transparent;
  transition: color 0.15s ease, border-color 0.15s ease;
}

.site-nav a:hover,
.site-nav a:focus-visible {
  color: var(--color-text);
  border-color: var(--color-accent);
}

/* Hero */
.hero {
  position: relative;
  padding: clamp(3.5rem, 12vw, 7rem) 0 calc(var(--space-section) * 0.85);
  overflow: hidden;
}

.hero-inner {
  position: relative;
  z-index: 1;
}

.hero-gradient {
  position: absolute;
  inset: -20% -10% auto 40%;
  height: 70%;
  max-height: 520px;
  background: radial-gradient(closest-side, var(--color-hero-tint), transparent 72%);
  pointer-events: none;
  opacity: 0.9;
}

.hero-eyebrow {
  margin: 0 0 0.75rem;
  font-size: 0.8125rem;
  font-weight: 600;
  letter-spacing: 0.12em;
  text-transform: uppercase;
  color: var(--color-accent);
}

.hero-title {
  margin: 0 0 1rem;
  font-size: clamp(1.875rem, 5vw, 2.75rem);
  font-weight: 700;
  line-height: 1.2;
  letter-spacing: -0.02em;
}

.hero-lead {
  margin: 0 0 1.75rem;
  max-width: 38rem;
  font-size: 1.0625rem;
  color: var(--color-text-muted);
}

.hero-actions {
  display: flex;
  flex-wrap: wrap;
  gap: 0.75rem 1rem;
}

.hide-mobile {
  display: none;
}

@media (min-width: 640px) {
  .hide-mobile {
    display: inline;
  }
}

/* Buttons */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  padding: 0.7rem 1.35rem;
  border-radius: 999px;
  font-weight: 600;
  font-size: 0.9375rem;
  text-decoration: none;
  border: 1px solid transparent;
  transition: background 0.15s ease, color 0.15s ease, border-color 0.15s ease, transform 0.1s ease;
}

.btn:active {
  transform: scale(0.98);
}

.btn-primary {
  background: var(--color-text);
  color: var(--color-bg);
}

.btn-primary:hover {
  background: #292524;
  color: var(--color-bg);
}

.btn-ghost {
  background: var(--color-surface);
  color: var(--color-text);
  border-color: var(--color-border);
}

.btn-ghost:hover {
  border-color: var(--color-text-muted);
  color: var(--color-text);
}

/* Sections */
.section {
  padding: var(--space-section) 0;
}

.section--surface {
  background: var(--color-surface);
  border-block: 1px solid var(--color-border);
}

.section-header {
  margin-bottom: clamp(2rem, 4vw, 2.75rem);
  max-width: 46rem;
}

.section-header--compact {
  margin-bottom: 1.25rem;
}

.section-header h2 {
  margin: 0 0 0.75rem;
  font-size: clamp(1.5rem, 3.5vw, 1.875rem);
  font-weight: 700;
  letter-spacing: -0.02em;
}

.section-desc {
  margin: 0;
  color: var(--color-text-muted);
  font-size: 1.0625rem;
}

.section-desc strong {
  color: var(--color-text);
  font-weight: 600;
}

/* About stats */
.about-stats {
  display: grid;
  gap: 1rem;
  list-style: none;
  margin: 0;
  padding: 0;
  grid-template-columns: 1fr;
}

@media (min-width: 720px) {
  .about-stats {
    grid-template-columns: repeat(3, 1fr);
    gap: 1.25rem;
  }
}

.about-stats li {
  padding: 1.35rem 1.25rem;
  border-radius: var(--radius);
  border: 1px solid var(--color-border);
  background: var(--color-surface);
  box-shadow: var(--shadow);
}

.stat-value {
  display: block;
  font-size: 1.25rem;
  font-weight: 700;
  margin-bottom: 0.35rem;
  color: var(--color-accent);
}

.stat-label {
  font-size: 0.9375rem;
  color: var(--color-text-muted);
}

/* Cards & grids */
.card {
  border-radius: var(--radius);
  border: 1px solid var(--color-border);
  background: var(--color-surface);
  box-shadow: var(--shadow);
}

.service-grid {
  display: grid;
  gap: 1.25rem;
  grid-template-columns: 1fr;
}

@media (min-width: 640px) {
  .service-grid {
    grid-template-columns: repeat(2, 1fr);
  }
}

@media (min-width: 960px) {
  .service-grid {
    grid-template-columns: repeat(3, 1fr);
  }
}

.service-card {
  padding: 1.5rem 1.35rem;
}

.service-card h3 {
  margin: 0 0 0.65rem;
  font-size: 1.125rem;
  font-weight: 600;
}

.service-card p {
  margin: 0 0 1rem;
  font-size: 0.9375rem;
  color: var(--color-text-muted);
}

.tag-list {
  display: flex;
  flex-wrap: wrap;
  gap: 0.4rem;
  list-style: none;
  margin: 0;
  padding: 0;
}

.tag-list li {
  font-size: 0.75rem;
  font-weight: 500;
  padding: 0.25rem 0.55rem;
  border-radius: 6px;
  background: var(--color-bg);
  color: var(--color-text-muted);
  border: 1px solid var(--color-border);
}

/* Keyword cloud */
.keyword-cloud {
  display: flex;
  flex-wrap: wrap;
  gap: 0.5rem;
}

.keyword-cloud span {
  display: inline-block;
  padding: 0.4rem 0.75rem;
  border-radius: 999px;
  background: var(--color-surface);
  border: 1px solid var(--color-border);
  font-size: 0.8125rem;
  color: var(--color-text-muted);
}

/* Process */
.process-steps {
  list-style: none;
  margin: 0;
  padding: 0;
  display: grid;
                gap: 0;
}

@media (min-width: 768px) {
  .process-steps {
    grid-template-columns: repeat(5, 1fr);
    gap: 1rem;
  }
}

.process-steps > li {
  display: flex;
  gap: 1rem;
  padding: 1.25rem 0;
  border-bottom: 1px solid var(--color-border);
}

@media (min-width: 768px) {
  .process-steps > li {
    flex-direction: column;
    padding: 1.25rem;
    border: 1px solid var(--color-border);
    border-radius: var(--radius);
    background: var(--color-surface);
    box-shadow: var(--shadow);
  }

  .process-steps > li:not(:last-child) {
    border-bottom: 1px solid var(--color-border);
  }
}

.step-index {
  flex-shrink: 0;
  font-size: 0.8125rem;
  font-weight: 700;
  letter-spacing: 0.06em;
  color: var(--color-accent);
}

.step-body h3 {
  margin: 0 0 0.35rem;
  font-size: 1rem;
  font-weight: 600;
}

.step-body p {
  margin: 0;
  font-size: 0.875rem;
  color: var(--color-text-muted);
}

/* Cases */
.case-grid {
  display: grid;
  gap: 1.25rem;
}

@media (min-width: 720px) {
  .case-grid {
    grid-template-columns: repeat(3, 1fr);
  }
}

.case-card {
  padding: 1.35rem 1.25rem;
}

.case-card h3 {
  margin: 0 0 0.5rem;
  font-size: 1.0625rem;
}

.case-card p {
  margin: 0;
  font-size: 0.9375rem;
  color: var(--color-text-muted);
}

/* Contact */
.contact-layout {
  display: grid;
  gap: 1.25rem;
}

@media (min-width: 800px) {
  .contact-layout {
    grid-template-columns: 1fr 1fr;
    align-items: start;
  }
}

.contact-card,
.contact-note {
  padding: 1.5rem 1.35rem;
}

.contact-list {
  margin: 0;
}

.contact-list > div {
  margin-bottom: 1.25rem;
}

.contact-list > div:last-child {
  margin-bottom: 0;
}

.contact-list dt {
  margin: 0 0 0.25rem;
  font-size: 0.75rem;
  font-weight: 600;
  text-transform: uppercase;
  letter-spacing: 0.06em;
  color: var(--color-text-muted);
}

.contact-list dd {
  margin: 0;
  font-size: 1.0625rem;
}

.contact-list a {
  font-weight: 500;
}

.mono {
  font-family: var(--font-mono);
  font-size: 1rem;
}

.contact-note h3 {
  margin: 0 0 0.75rem;
  font-size: 1rem;
}

.contact-note ul {
  margin: 0;
  padding-left: 1.15rem;
  color: var(--color-text-muted);
  font-size: 0.9375rem;
}

.contact-note li + li {
  margin-top: 0.4rem;
}

/* Footer */
.site-footer {
  padding: 2rem 0 2.5rem;
  border-top: 1px solid var(--color-border);
  background: var(--color-surface);
}

.footer-inner {
  text-align: center;
}

.footer-brand {
  margin: 0 0 0.5rem;
  font-size: 0.875rem;
  color: var(--color-text-muted);
}

.footer-meta {
  margin: 0;
  font-size: 0.8125rem;
  color: #a8a29e;
}

/* Mobile nav */
@media (max-width: 767px) {
  .nav-toggle {
    display: flex;
  }

  .site-nav {
    position: absolute;
    left: 0;
    right: 0;
    top: 100%;
    background: rgba(250, 250, 249, 0.98);
    backdrop-filter: blur(10px);
    border-bottom: 1px solid var(--color-border);
    max-height: 0;
    overflow: hidden;
    transition: max-height 0.35s ease;
  }

  .site-nav.is-open {
    max-height: 320px;
  }

  .site-nav .nav-list {
    flex-direction: column;
    align-items: stretch;
    padding: 0.75rem 1rem 1.25rem;
    gap: 0;
  }

  .site-nav .nav-list a {
    display: block;
    padding: 0.75rem 0;
    border-bottom: 1px solid var(--color-border);
  }

  .site-nav .nav-list li:last-child a {
    border-bottom: none;
  }
}