/* ============================================================
   Filteray 医疗视光 — 共享样式表
   Mobile-first, responsive, accessible. No external dependencies.
   ============================================================ */

/* ---------- Design tokens ---------- */
:root {
  --color-primary: #0f5c3e;
  --color-primary-dark: #083d29;
  --color-primary-light: #e7f2ee;
  --color-accent: #c89f3a;
  --color-accent-dark: #a6822a;
  --color-ink: #16242e;
  --color-muted: #5b6b78;
  --color-bg: #ffffff;
  --color-bg-alt: #f4f8f6;
  --color-border: #d8e4de;
  --color-focus: #f2c84b;

  --maxw: 1180px;
  --radius: 14px;
  --radius-sm: 8px;
  --shadow-sm: 0 1px 3px rgba(16, 36, 46, 0.08);
  --shadow-md: 0 8px 24px rgba(16, 36, 46, 0.10);
  --shadow-lg: 0 18px 48px rgba(16, 36, 46, 0.14);

  --font-sans: "Segoe UI", system-ui, -apple-system, Roboto, Helvetica, Arial,
    "PingFang SC", "Microsoft YaHei", sans-serif;

  --space-1: 0.5rem;
  --space-2: 1rem;
  --space-3: 1.5rem;
  --space-4: 2rem;
  --space-5: 3rem;
  --space-6: 5rem;
}

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

html {
  scroll-behavior: smooth;
}

body {
  margin: 0;
  font-family: var(--font-sans);
  color: var(--color-ink);
  background: var(--color-bg);
  line-height: 1.65;
  font-size: 17px;
  -webkit-font-smoothing: antialiased;
}

img,
svg {
  max-width: 100%;
  display: block;
}

a {
  color: var(--color-primary);
  text-decoration: none;
}
a:hover {
  text-decoration: underline;
}

h1,
h2,
h3,
h4 {
  line-height: 1.2;
  margin: 0 0 var(--space-2);
  color: var(--color-ink);
  font-weight: 700;
}
h1 {
  font-size: clamp(2rem, 5vw, 3.25rem);
}
h2 {
  font-size: clamp(1.6rem, 3.5vw, 2.4rem);
}
h3 {
  font-size: 1.25rem;
}
p {
  margin: 0 0 var(--space-2);
}

/* Visible focus for keyboard users */
:focus-visible {
  outline: 3px solid var(--color-focus);
  outline-offset: 2px;
  border-radius: 4px;
}

/* Skip link (a11y) */
.skip-link {
  position: absolute;
  left: -999px;
  top: 0;
  background: var(--color-primary);
  color: #fff;
  padding: 0.75rem 1.25rem;
  z-index: 1000;
  border-radius: 0 0 var(--radius-sm) 0;
}
.skip-link:focus {
  left: 0;
}

/* ---------- Layout helpers ---------- */
.container {
  width: 100%;
  max-width: var(--maxw);
  margin-inline: auto;
  padding-inline: var(--space-2);
}

.section {
  padding-block: var(--space-6);
}
.section--alt {
  background: var(--color-bg-alt);
}
.section--tight {
  padding-block: var(--space-5);
}

.eyebrow {
  display: inline-block;
  font-size: 0.8rem;
  letter-spacing: 0.12em;
  text-transform: uppercase;
  font-weight: 700;
  color: var(--color-primary);
  margin-bottom: var(--space-1);
}

.lead {
  font-size: 1.15rem;
  color: var(--color-muted);
  max-width: 60ch;
}

.text-center {
  text-align: center;
}
.mx-auto {
  margin-inline: auto;
}

/* ---------- Buttons ---------- */
.btn {
  display: inline-flex;
  align-items: center;
  gap: 0.5rem;
  padding: 0.8rem 1.5rem;
  border-radius: 999px;
  font-weight: 700;
  font-size: 1rem;
  border: 2px solid transparent;
  cursor: pointer;
  transition: transform 0.12s ease, background 0.2s ease, box-shadow 0.2s ease;
  text-decoration: none;
}
.btn:hover {
  text-decoration: none;
  transform: translateY(-1px);
}
.btn-primary {
  background: var(--color-accent);
  color: #1a1300;
}
.btn-primary:hover {
  background: var(--color-accent-dark);
}
.btn-secondary {
  background: var(--color-primary);
  color: #fff;
}
.btn-secondary:hover {
  background: var(--color-primary-dark);
}
.btn-ghost {
  background: transparent;
  color: var(--color-primary);
  border-color: var(--color-primary);
}
.btn-ghost:hover {
  background: var(--color-primary-light);
}
.btn-lg {
  padding: 1rem 2rem;
  font-size: 1.1rem;
}

/* ---------- Header / Nav ---------- */
.site-header {
  position: sticky;
  top: 0;
  z-index: 100;
  background: rgba(255, 255, 255, 0.92);
  backdrop-filter: saturate(140%) blur(8px);
  border-bottom: 1px solid var(--color-border);
}
.nav {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: var(--space-2);
  height: 68px;
}
.brand {
  display: flex;
  align-items: center;
  gap: 0.6rem;
  font-weight: 800;
  font-size: 1.2rem;
  color: var(--color-ink);
}
.brand:hover {
  text-decoration: none;
}
.brand svg {
  width: 34px;
  height: 34px;
  flex: none;
}
.brand img {
  height: 36px;
  width: auto;
  flex: none;
}

.nav-links {
  display: flex;
  align-items: center;
  gap: 0.25rem;
  list-style: none;
  margin: 0;
  padding: 0;
}
.nav-links a {
  display: inline-block;
  padding: 0.55rem 0.9rem;
  border-radius: var(--radius-sm);
  color: var(--color-ink);
  font-weight: 600;
  font-size: 0.98rem;
}
.nav-links a:hover {
  background: var(--color-primary-light);
  text-decoration: none;
}
.nav-links a[aria-current="page"] {
  color: var(--color-primary);
  background: var(--color-primary-light);
}

.nav-actions {
  display: flex;
  align-items: center;
  gap: var(--space-1);
}

/* Hamburger (mobile) */
.nav-toggle {
  display: none;
  background: transparent;
  border: 1px solid var(--color-border);
  border-radius: var(--radius-sm);
  width: 44px;
  height: 44px;
  cursor: pointer;
  padding: 0;
  align-items: center;
  justify-content: center;
}
.nav-toggle svg {
  width: 24px;
  height: 24px;
}

/* ---------- Hero ---------- */
.hero {
  position: relative;
  overflow: hidden;
  background: linear-gradient(135deg, var(--color-primary-dark), var(--color-primary));
  color: #fff;
}
.hero::after {
  /* subtle decorative pattern */
  content: "";
  position: absolute;
  inset: 0;
  background-image: radial-gradient(rgba(255, 255, 255, 0.12) 1px, transparent 1px);
  background-size: 22px 22px;
  opacity: 0.5;
  pointer-events: none;
}
.hero .container {
  position: relative;
  z-index: 1;
  display: grid;
  gap: var(--space-4);
  grid-template-columns: 1fr;
  align-items: center;
  padding-block: var(--space-6);
}
.hero h1 {
  color: #fff;
}
.hero .lead {
  color: rgba(255, 255, 255, 0.9);
}
.hero-cta {
  display: flex;
  flex-wrap: wrap;
  gap: var(--space-2);
  margin-top: var(--space-2);
}
.hero-visual {
  border-radius: var(--radius);
  background: rgba(255, 255, 255, 0.08);
  border: 1px solid rgba(255, 255, 255, 0.18);
  padding: var(--space-3);
  box-shadow: var(--shadow-lg);
}

/* ---------- Card grid ---------- */
.grid {
  display: grid;
  gap: var(--space-3);
  grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
}
.grid-3 {
  grid-template-columns: repeat(auto-fit, minmax(260px, 1fr));
}

.card {
  background: var(--color-bg);
  border: 1px solid var(--color-border);
  border-radius: var(--radius);
  padding: var(--space-3);
  box-shadow: var(--shadow-sm);
  transition: transform 0.15s ease, box-shadow 0.15s ease, border-color 0.15s ease;
  display: flex;
  flex-direction: column;
  height: 100%;
}
.card:hover {
  transform: translateY(-4px);
  box-shadow: var(--shadow-md);
  border-color: var(--color-primary);
}
.card-icon {
  width: 52px;
  height: 52px;
  border-radius: 12px;
  background: var(--color-primary-light);
  color: var(--color-primary);
  display: grid;
  place-items: center;
  margin-bottom: var(--space-2);
}
.card-icon svg {
  width: 28px;
  height: 28px;
}
.card h3 {
  margin-bottom: 0.4rem;
}
.card p {
  color: var(--color-muted);
  margin-bottom: var(--space-2);
}
.card .card-link {
  margin-top: auto;
  font-weight: 700;
}

/* ---------- Feature / split row ---------- */
.split {
  display: grid;
  gap: var(--space-4);
  grid-template-columns: 1fr;
  align-items: center;
}
.split-visual {
  border-radius: var(--radius);
  background: linear-gradient(160deg, var(--color-primary-light), #fff);
  border: 1px solid var(--color-border);
  padding: var(--space-3);
  display: grid;
  place-items: center;
  min-height: 260px;
}

/* ---------- Stats ---------- */
.stats {
  display: grid;
  gap: var(--space-3);
  grid-template-columns: repeat(auto-fit, minmax(160px, 1fr));
  text-align: center;
}
.stat-num {
  font-size: 2.6rem;
  font-weight: 800;
  color: var(--color-primary);
  line-height: 1;
}
.stat-label {
  color: var(--color-muted);
  font-weight: 600;
}

/* ---------- Forms ---------- */
.form {
  display: grid;
  gap: var(--space-2);
  max-width: 620px;
}
.field {
  display: grid;
  gap: 0.4rem;
}
.field label {
  font-weight: 600;
}
.field input,
.field textarea,
.field select {
  font: inherit;
  padding: 0.75rem 0.9rem;
  border: 1px solid var(--color-border);
  border-radius: var(--radius-sm);
  background: #fff;
  color: var(--color-ink);
  width: 100%;
}
.field input:focus,
.field textarea:focus,
.field select:focus {
  border-color: var(--color-primary);
  outline: 3px solid var(--color-focus);
  outline-offset: 1px;
}
.field textarea {
  min-height: 140px;
  resize: vertical;
}
.form-note {
  font-size: 0.9rem;
  color: var(--color-muted);
}
.form-status {
  padding: 0.9rem 1.1rem;
  border-radius: var(--radius-sm);
  font-weight: 600;
  display: none;
}
.form-status.ok {
  display: block;
  background: #e7f6ec;
  color: #1d6b3a;
  border: 1px solid #b6e0c4;
}
.form-status.err {
  display: block;
  background: #fdeaea;
  color: #a3242b;
  border: 1px solid #f1b9bc;
}

/* ---------- Breadcrumb ---------- */
.breadcrumb {
  font-size: 0.9rem;
  color: var(--color-muted);
  padding-block: var(--space-2);
}
.breadcrumb a {
  color: var(--color-muted);
}

/* ---------- Page hero (interior pages) ---------- */
.page-hero {
  background: var(--color-bg-alt);
  border-bottom: 1px solid var(--color-border);
  padding-block: var(--space-5);
}

/* ---------- Footer ---------- */
.site-footer {
  background: var(--color-primary-dark);
  color: rgba(255, 255, 255, 0.86);
  padding-block: var(--space-5) var(--space-3);
}
.site-footer h4 {
  color: #fff;
  font-size: 1.05rem;
  margin-bottom: var(--space-2);
}
.footer-grid {
  display: grid;
  gap: var(--space-4);
  grid-template-columns: 1fr;
}
.footer-grid a {
  color: rgba(255, 255, 255, 0.8);
  display: inline-block;
  padding: 0.2rem 0;
}
.footer-grid a:hover {
  color: #fff;
}
.footer-bottom {
  border-top: 1px solid rgba(255, 255, 255, 0.15);
  margin-top: var(--space-4);
  padding-top: var(--space-3);
  font-size: 0.9rem;
  color: rgba(255, 255, 255, 0.7);
  display: flex;
  flex-wrap: wrap;
  gap: var(--space-2);
  justify-content: space-between;
}

/* ---------- Callout ---------- */
.callout {
  border-left: 4px solid var(--color-accent);
  background: var(--color-bg-alt);
  padding: var(--space-3);
  border-radius: 0 var(--radius-sm) var(--radius-sm) 0;
}

/* ---------- Table ---------- */
.table-wrap {
  overflow-x: auto;
  border: 1px solid var(--color-border);
  border-radius: var(--radius);
}
table {
  border-collapse: collapse;
  width: 100%;
  min-width: 520px;
}
th,
td {
  text-align: left;
  padding: 0.85rem 1rem;
  border-bottom: 1px solid var(--color-border);
}
th {
  background: var(--color-bg-alt);
  font-weight: 700;
}

/* ============================================================
   Responsive: tablet & desktop
   ============================================================ */
@media (min-width: 720px) {
  .footer-grid {
    grid-template-columns: 1.4fr 1fr 1fr 1fr;
  }
  .split {
    grid-template-columns: 1fr 1fr;
  }
  .hero .container {
    grid-template-columns: 1.1fr 0.9fr;
  }
}

/* ============================================================
   Responsive: mobile nav (<= 859px)
   ============================================================ */
@media (max-width: 859px) {
  .brand img {
    height: 30px;
  }
  .nav-toggle {
    display: inline-flex;
  }
  .nav-links {
    position: absolute;
    top: 68px;
    left: 0;
    right: 0;
    background: #fff;
    flex-direction: column;
    align-items: stretch;
    gap: 0;
    padding: var(--space-2);
    border-bottom: 1px solid var(--color-border);
    box-shadow: var(--shadow-md);
    display: none;
  }
  .nav-links.open {
    display: flex;
  }
  .nav-links a {
    padding: 0.85rem 1rem;
  }
  /* hide the inline CTA button inside header on small screens to save space */
  .nav-actions .btn {
    display: none;
  }
  /* show the CTA as a full-width item inside the mobile menu */
  .mobile-cta {
    display: block;
    margin-top: var(--space-1);
  }
  .mobile-cta .btn {
    width: 100%;
    justify-content: center;
  }
}
/* hide the in-menu CTA on desktop (the header already shows one) */
.mobile-cta {
  display: none;
}

/* Respect reduced motion */
@media (prefers-reduced-motion: reduce) {
  * {
    scroll-behavior: auto !important;
    transition: none !important;
    animation: none !important;
  }
}