/* ============================================================
   水产虾类大全 · 首页
   白底 + 海军蓝 #0f355e + 亮蓝 #2f7fd4（对齐 03-ui 视觉稿）
   ============================================================ */

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

html { scroll-behavior: smooth; }

body {
  margin: 0;
  background: var(--bg);
  color: var(--text-body);
  font-family: var(--sans);
  font-size: 14px;
  line-height: 1.6;
  -webkit-font-smoothing: antialiased;
}

img { display: block; max-width: 100%; height: auto; }
a { color: inherit; text-decoration: none; }
h1, h2, h3 {
  margin: 0;
  font-family: var(--sans);
  font-weight: 700;
  color: var(--navy);
  letter-spacing: 0;
}
p { margin: 0; }
ul, ol, dl, dd { margin: 0; padding: 0; }
li { list-style: none; }
button { font: inherit; color: inherit; }

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

:focus-visible { outline: 2px solid var(--accent); outline-offset: 3px; }

.skip-link {
  position: absolute;
  left: 16px;
  top: -60px;
  z-index: 100;
  padding: 8px 16px;
  background: var(--navy);
  color: #fff;
  font-size: 12px;
  transition: top 0.2s var(--ease);
}
.skip-link:focus { top: 10px; }

.shell-container {
  width: 100%;
  max-width: var(--shell);
  margin: 0 auto;
  padding-inline: var(--pad);
}

/* ---------------------------------------------------------- header */

.site-header {
  position: sticky;
  top: 0;
  z-index: 50;
  background: rgba(255, 255, 255, 0.96);
  border-bottom: 1px solid var(--line);
  backdrop-filter: blur(12px);
}
.site-header.is-scrolled { box-shadow: 0 4px 18px rgba(15, 53, 94, 0.06); }

.header-inner {
  display: flex;
  align-items: center;
  gap: 28px;
  min-height: 62px;
}

.brand { display: inline-flex; align-items: center; gap: 9px; flex: none; }
.brand-seal {
  display: grid;
  place-items: center;
  width: 28px;
  height: 28px;
  border-radius: 50%;
  background: var(--accent);
  color: #fff;
  font-size: 13px;
  line-height: 1;
}
.brand-name {
  font-size: 17px;
  font-weight: 700;
  letter-spacing: 0.04em;
  color: var(--navy);
}

.site-nav {
  display: flex;
  align-items: center;
  gap: 20px;
  margin-left: auto;
}
.nav-link {
  position: relative;
  padding: 6px 0;
  font-size: 12.5px;
  color: #33475b;
  white-space: nowrap;
  transition: color 0.2s var(--ease);
}
.nav-link::after {
  content: "";
  position: absolute;
  left: 0;
  right: 0;
  bottom: 0;
  height: 2px;
  background: var(--accent);
  transform: scaleX(0);
  transform-origin: left;
  transition: transform 0.22s var(--ease);
}
.nav-link:hover { color: var(--accent); }
.nav-link:hover::after { transform: scaleX(1); }
.nav-link.is-active { color: var(--accent); font-weight: 600; }
.nav-link.is-active::after { transform: scaleX(1); }

.menu-btn {
  display: none;
  width: 38px;
  height: 38px;
  padding: 0;
  border: 1px solid var(--line-strong);
  border-radius: 4px;
  background: transparent;
  cursor: pointer;
}
.menu-btn span {
  display: block;
  width: 16px;
  height: 1.5px;
  margin: 3.5px auto;
  background: var(--navy);
  transition: transform 0.25s var(--ease), opacity 0.2s var(--ease);
}
.menu-btn[aria-expanded="true"] span:nth-child(1) { transform: translateY(5px) rotate(45deg); }
.menu-btn[aria-expanded="true"] span:nth-child(2) { opacity: 0; }
.menu-btn[aria-expanded="true"] span:nth-child(3) { transform: translateY(-5px) rotate(-45deg); }

/* ---------------------------------------------------------- hero */

.hero {
  position: relative;
  min-height: 399px;
  display: flex;
  align-items: center;
  overflow: hidden;
  background: #e8f3fb;
}
.hero::before {
  content: "";
  position: absolute;
  top: 0;
  right: 0;
  width: 60%;
  height: 100%;
  background: url("../images/hero-right.jpg") right center / cover no-repeat;
}
.hero::after {
  content: "";
  position: absolute;
  inset: 0;
  background: linear-gradient(90deg, #eef6fc 0%, rgba(238, 246, 252, 0.96) 38%, rgba(238, 246, 252, 0.55) 55%, rgba(238, 246, 252, 0) 76%);
}

.hero-grid { position: relative; z-index: 1; display: flex; align-items: center; }
.hero-copy { width: min(590px, 58%); padding: 46px 0 42px; }

.eyebrow {
  display: flex;
  align-items: center;
  gap: 9px;
  font-size: 10.5px;
  font-weight: 600;
  letter-spacing: 0.18em;
  text-transform: uppercase;
  color: var(--accent);
}
.eyebrow::before {
  content: "";
  width: 26px;
  height: 2px;
  background: var(--accent);
}

.hero h1 {
  margin: 14px 0 14px;
  font-size: 46px;
  line-height: 1.15;
  letter-spacing: 0.01em;
}

.hero-lede {
  max-width: 33em;
  font-size: 13.5px;
  line-height: 1.8;
  color: #33475b;
}

.hero-actions { display: flex; flex-wrap: wrap; gap: 10px; margin-top: 22px; }

.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  min-height: 40px;
  padding: 0 20px;
  border-radius: 3px;
  border: 1px solid transparent;
  font-size: 12.5px;
  font-weight: 500;
  transition: background 0.2s var(--ease), color 0.2s var(--ease), border-color 0.2s var(--ease);
}
.btn-primary { background: var(--accent); color: #fff; }
.btn-primary:hover { background: var(--accent-deep); }
.btn-ghost { background: #fff; border-color: var(--accent); color: var(--accent); }
.btn-ghost:hover { background: var(--accent); color: #fff; }

.hero-meta {
  margin-top: 18px;
  font-size: 11.5px;
  color: var(--muted);
}

/* ---------------------------------------------------------- shared head */

.section-head { display: flex; align-items: baseline; justify-content: space-between; gap: 20px; }
.section-head h2 { font-size: 26px; line-height: 1.3; }
.section-sub { margin-top: 6px; font-size: 12.5px; color: var(--muted); }

/* ---------------------------------------------------------- categories */

.categories { padding: 40px 0 36px; background: #fff; }

.cat-index {
  display: grid;
  grid-template-columns: repeat(4, minmax(0, 1fr));
  margin-top: 20px;
  border-top: 1px solid var(--line);
  border-left: 1px solid var(--line);
}

.cat-row {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 12px;
  min-height: 168px;
  padding: 16px 15px;
  border-right: 1px solid var(--line);
  border-bottom: 1px solid var(--line);
  transition: background 0.2s var(--ease);
}
.cat-row:hover { background: var(--bg-soft); }

.cat-text { min-width: 0; }
.cat-num { font-size: 10.5px; font-weight: 600; color: var(--accent); }
.cat-name { margin: 1px 0 5px; font-size: 15px; }
.cat-desc { font-size: 10.5px; line-height: 1.55; color: var(--muted); display: -webkit-box; -webkit-line-clamp: 3; -webkit-box-orient: vertical; overflow: hidden; }
.cat-row img {
  flex: none;
  width: 104px;
  height: 68px;
  object-fit: cover;
  border-radius: 4px;
}
.cat-arrow { display: none; }

.cat-cell-empty {
  min-height: 168px;
  border-right: 1px solid var(--line);
  border-bottom: 1px solid var(--line);
  background: linear-gradient(135deg, #fbfdff 0%, #f1f8ff 100%);
}

/* ---------------------------------------------------------- featured */

.featured { padding: 0 0 73px; background: #fff; }
.featured .section-head h2 { font-size: 24px; }

.featured-grid {
  display: grid;
  grid-template-columns: repeat(4, minmax(0, 1fr));
  gap: 16px;
  margin-top: 10px;
}

.feature-card {
  position: relative;
  display: flex;
  flex-direction: column;
  overflow: hidden;
  border: 1px solid var(--line);
  border-radius: 6px;
  background: #fff;
  box-shadow: 0 2px 10px rgba(15, 53, 94, 0.04);
  transition: box-shadow 0.2s var(--ease), transform 0.2s var(--ease);
}
.feature-card:hover { transform: translateY(-2px); box-shadow: var(--shadow-card); }

.feature-img { position: relative; display: block; overflow: hidden; background: var(--bg-soft); }
.feature-img::after {
  content: attr(data-tag);
  position: absolute;
  left: 10px;
  bottom: 9px;
  padding: 1px 7px;
  border-radius: 2px;
  background: var(--accent);
  color: #fff;
  font-size: 9.5px;
  line-height: 1.7;
}
.feature-img img {
  width: 100%;
  aspect-ratio: 2.4 / 1;
  object-fit: cover;
  transition: transform 0.5s var(--ease);
}
.feature-card:hover .feature-img img { transform: scale(1.03); }

.feature-body { display: flex; flex-direction: column; gap: 6px; padding: 10px 12px 11px; }
.feature-body h3 { font-size: 12.5px; line-height: 1.4; display: -webkit-box; -webkit-line-clamp: 2; -webkit-box-orient: vertical; overflow: hidden; }
.feature-body h3 a:hover { color: var(--accent); }
.feature-body p { font-size: 10px; line-height: 1.5; color: var(--muted); display: -webkit-box; -webkit-line-clamp: 2; -webkit-box-orient: vertical; overflow: hidden; }
.feature-body .tag { position: absolute; width: 1px; height: 1px; overflow: hidden; clip-path: inset(50%); white-space: nowrap; }

.tag {
  align-self: flex-start;
  margin-top: 2px;
  padding: 1px 8px;
  border-radius: 2px;
  background: var(--accent-soft);
  color: var(--accent-deep);
  font-size: 10px;
  line-height: 1.6;
  transition: background 0.2s var(--ease), color 0.2s var(--ease);
}
.tag:hover { background: var(--accent); color: #fff; }

/* ---------------------------------------------------------- shell + steps */

.shell-band { padding: 58px 0 54px; background: var(--bg-soft); }

.shell-grid {
  display: grid;
  grid-template-columns: minmax(0, 0.95fr) minmax(0, 1.2fr);
  gap: 32px;
  align-items: start;
  min-height: 235px;
}
.shell-copy h2 { font-size: 24px; line-height: 1.35; }
.shell-copy p { margin-top: 10px; font-size: 12px; line-height: 1.85; color: var(--muted); }

.shell-list {
  display: grid;
  grid-template-columns: repeat(4, minmax(0, 1fr));
  gap: 14px;
}
.shell-item { display: block; }
.shell-item img { width: 88px; height: 88px; object-fit: cover; border-radius: 3px; }
.shell-item h3 { font-size: 13.5px; margin: 8px 0 3px; }
.shell-item p { font-size: 10.5px; line-height: 1.55; color: var(--muted); }

.steps-panel {
  margin-top: 26px;
  padding: 24px 24px 26px;
  background: #fff;
  border: 1px solid var(--line);
}
.steps-panel h2 { font-size: 20px; margin-bottom: 18px; }

.steps-grid { display: grid; grid-template-columns: repeat(3, minmax(0, 1fr)); gap: 22px; }
.step { position: relative; padding-left: 34px; }
.step::before {
  content: attr(data-step);
  position: absolute;
  left: 0;
  top: 0;
  display: grid;
  place-items: center;
  width: 23px;
  height: 23px;
  border-radius: 50%;
  background: var(--accent);
  color: #fff;
  font-size: 9.5px;
  font-weight: 600;
}
.step h3 { font-size: 14px; margin-bottom: 5px; }
.step p { font-size: 11px; line-height: 1.7; color: var(--muted); }

/* ---------------------------------------------------------- collection + latest */

.collection { padding: 20px 0 17px; background: #fff; }
.collection-grid {
  display: grid;
  grid-template-columns: minmax(0, 1.05fr) minmax(0, 1fr);
  gap: 40px;
  align-items: start;
}
.collection-copy h2 { font-size: 20px; margin-bottom: 7px; }
.collection-copy p { font-size: 11px; line-height: 1.6; color: var(--muted); max-width: 40em; }

.collection-stats {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 7px;
  margin-top: 11px;
}
.stat {
  display: flex;
  align-items: center;
  gap: 7px;
  padding: 6px 9px;
  background: var(--bg-soft);
  border: 1px solid var(--line);
}
.stat dt { font-size: 18px; font-weight: 700; line-height: 1; color: var(--accent); }
.stat dd { margin: 0; font-size: 9.5px; color: var(--muted); }

.latest h2 { font-size: 20px; margin-bottom: 6px; }
.latest-list li {
  display: flex;
  align-items: baseline;
  justify-content: space-between;
  gap: 18px;
  padding: 3px 0;
  border-bottom: 1px solid var(--line);
}
.latest-list a { font-size: 11.5px; line-height: 1.5; color: var(--text-strong); transition: color 0.2s var(--ease); }
.latest-list a:hover { color: var(--accent); }
.latest-list time { flex: none; font-size: 10.5px; color: var(--muted); font-variant-numeric: tabular-nums; }
.latest-note { display: none; }

/* ---------------------------------------------------------- footer */

.site-footer { padding: 36px 0 23px; background: var(--navy); color: #fff; }

.footer-grid {
  display: grid;
  grid-template-columns: minmax(0, 1.25fr) minmax(0, 1.5fr) minmax(0, 0.6fr) minmax(0, 0.9fr);
  gap: 28px;
  align-items: start;
}
.brand-light .brand-name { color: #fff; }
.brand-light .brand-seal { background: #fff; color: var(--navy); }
.footer-brand p { margin-top: 10px; max-width: 26em; font-size: 10.5px; line-height: 1.7; color: var(--on-dark); }

.footer-col { display: flex; flex-direction: column; gap: 3px; }
.footer-col h3 {
  margin-bottom: 6px;
  font-size: 9.5px;
  font-weight: 600;
  letter-spacing: 0.14em;
  color: var(--on-dark-soft);
}
.footer-col a { width: fit-content; font-size: 10.5px; line-height: 1.9; color: var(--on-dark); transition: color 0.2s var(--ease); }
.footer-col a:hover { color: #fff; }
.footer-link-grid { display: grid; grid-template-columns: repeat(2, minmax(0, 1fr)); gap: 0 16px; }

.footer-legal { display: flex; flex-direction: column; gap: 6px; font-size: 9.5px; line-height: 1.6; color: var(--on-dark-soft); }
.footer-legal p:last-child { color: var(--on-dark); }

/* ---------------------------------------------------------- responsive */

@media (max-width: 1180px) {
  .site-nav { gap: 12px; }
  .nav-link { font-size: 11.5px; }
  .cat-row img { width: 80px; height: 80px; }
}

@media (max-width: 1024px) {
  .site-nav {
    position: fixed;
    inset: 68px 0 auto;
    display: none;
    flex-direction: column;
    align-items: stretch;
    gap: 0;
    margin: 0;
    padding: 8px var(--pad) 18px;
    background: #fff;
    border-bottom: 1px solid var(--line-strong);
    box-shadow: 0 18px 30px rgba(15, 53, 94, 0.08);
  }
  .site-nav.is-open { display: flex; }
  .nav-link { padding: 12px 0; font-size: 14px; border-bottom: 1px solid var(--line); }
  .nav-link::after { display: none; }
  .menu-btn { display: block; margin-left: auto; }

  .hero { min-height: 360px; }
  .hero-copy { width: min(560px, 70%); }

  .cat-index { grid-template-columns: repeat(2, minmax(0, 1fr)); }
  .featured-grid { grid-template-columns: repeat(2, minmax(0, 1fr)); }
  .shell-grid { grid-template-columns: 1fr; gap: 20px; }
  .collection-grid { grid-template-columns: 1fr; gap: 24px; }
  .footer-grid { grid-template-columns: repeat(2, minmax(0, 1fr)); }
  .footer-brand { grid-column: 1 / -1; }
}

@media (max-width: 640px) {
  :root { --pad: 20px; }
  .header-inner { min-height: 60px; }
  .site-nav { inset: 60px 0 auto; }
  .brand-name { font-size: 15px; }
  .brand-seal { width: 25px; height: 25px; font-size: 12px; }

  .hero {
    min-height: 0;
    background-image:
      linear-gradient(180deg, rgba(255, 255, 255, 0.97) 0%, rgba(255, 255, 255, 0.9) 62%, rgba(255, 255, 255, 0.62) 100%),
      url("../images/hero-lake2.jpg");
    background-position: center, center, 70% center;
  }
  .hero-copy { width: 100%; padding: 34px 0 30px; }
  .hero h1 { font-size: 34px; }
  .hero-lede { font-size: 12.5px; }
  .btn { min-height: 38px; padding: 0 16px; font-size: 12px; }

  .categories { padding: 30px 0 28px; }
  .section-head { flex-direction: column; align-items: flex-start; gap: 4px; }
  .section-head h2 { font-size: 21px; }
  .cat-index { grid-template-columns: 1fr; }
  .cat-row { min-height: 116px; }
  .cat-row img { width: 84px; height: 84px; }
  .cat-cell-empty { display: none; }

  .featured { padding-bottom: 28px; }
  .featured-grid { grid-template-columns: 1fr; gap: 14px; }
  .feature-body h3 { font-size: 14px; }
  .feature-body p { font-size: 11px; }

  .shell-band { padding: 28px 0; }
  .shell-list { grid-template-columns: 1fr; gap: 10px; }
  .shell-item img { width: 54px; height: 54px; }
  .steps-panel { padding: 16px; }
  .steps-grid { grid-template-columns: 1fr; gap: 14px; }

  .collection { padding: 26px 0; }
  .collection-stats { grid-template-columns: repeat(2, minmax(0, 1fr)); }
  .latest-list a { font-size: 11px; }

  .footer-grid { grid-template-columns: 1fr 1fr; gap: 20px; }
  .footer-brand { grid-column: 1 / -1; }
  .footer-legal { grid-column: 1 / -1; }
}

@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;
  }
}