@charset "UTF-8";
/* ==========================================================================
   layout.css · 容器/栅格、顶栏、面包屑、页脚、section 深浅底、吸底 CTA 条、
   Hero 渐变与网格底纹
   移动优先：基础样式 = <640px 单列；向上用 min-width 覆盖
   ========================================================================== */

/* ------------------------------ 容器与栅格 ------------------------------ */

.container {
  width: 100%;
  max-width: var(--container);
  margin-inline: auto;
  padding-inline: 16px;
}

@media (min-width: 1024px) {
  .container { padding-inline: 24px; }
}

.main { display: block; min-height: 60vh; }

.grid {
  display: grid;
  grid-template-columns: 1fr;
  gap: var(--sp-4);
}

@media (min-width: 640px) {
  .grid { grid-template-columns: repeat(2, minmax(0, 1fr)); gap: var(--sp-5); }
}

@media (min-width: 1024px) {
  .grid--3 { grid-template-columns: repeat(3, minmax(0, 1fr)); }
  .grid--4 { grid-template-columns: repeat(4, minmax(0, 1fr)); }
  .grid { gap: var(--sp-5); }
}

.stack > * + * { margin-top: var(--sp-4); }

/* ------------------------------ 板块容器 ------------------------------ */

.section {
  padding-block: var(--sp-7);
}

@media (min-width: 1024px) {
  .section { padding-block: var(--sp-9); }
}

.section { background: var(--bg-surface); }
.section--alt { background: var(--bg-tint); }
.section--white { background: var(--bg-surface); }
.section--tight { padding-block: var(--sp-6); }

.section--dark {
  background: var(--bg-mid);
  color: var(--tx-on-dark-2);
}

.section--dark h1,
.section--dark h2,
.section--dark h3 { color: var(--tx-on-dark-1); }

.section--dark p,
.section--dark li { color: var(--tx-on-dark-2); }

.section--hero {
  position: relative;
  padding-block: var(--sp-8) var(--sp-8);
  background: var(--grad-hero);
  color: var(--tx-on-dark-1);
  overflow: hidden;
}

@media (min-width: 1024px) {
  .section--hero { padding-block: var(--sp-9) var(--sp-9); }
}

/* Hero 极淡网格底纹 */
.section--hero::before {
  content: "";
  position: absolute;
  inset: 0;
  background-image:
    repeating-linear-gradient(0deg, rgba(255, 255, 255, .04) 0 1px, transparent 1px 48px),
    repeating-linear-gradient(90deg, rgba(255, 255, 255, .04) 0 1px, transparent 1px 48px);
  pointer-events: none;
}

.section--hero > .container { position: relative; z-index: 1; }

.section--hero h1 { color: var(--tx-on-dark-1); }

.section-head { max-width: 760px; margin-bottom: var(--sp-6); }

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

.section-head__eyebrow {
  margin: 0 0 var(--sp-2);
  font-size: var(--fs-sm);
  letter-spacing: .12em;
  color: var(--c-brand);
  text-transform: uppercase;
}

.section--dark .section-head__eyebrow { color: var(--c-brand-2); }

.section-head__title { margin-bottom: var(--sp-3); }

.section-head__sub {
  margin: 0;
  font-size: var(--fs-md);
  color: var(--tx-2);
}

.section--dark .section-head__sub { color: var(--tx-on-dark-2); }

/* ------------------------------ 顶栏与导航 ------------------------------ */

.topbar {
  position: sticky;
  top: 0;
  z-index: 50;
  background: rgba(15, 23, 42, .92);
  backdrop-filter: blur(12px);
  -webkit-backdrop-filter: blur(12px);
  border-bottom: 1px solid rgba(148, 163, 184, .18);
}

.topbar__inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: var(--sp-4);
  min-height: 64px;
}

.brand {
  display: flex;
  align-items: center;
  gap: var(--sp-3);
  color: var(--tx-on-dark-1);
}

.brand__mark {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  width: 38px;
  height: 38px;
  border-radius: var(--radius-ctl);
  background: linear-gradient(135deg, var(--c-brand) 0%, var(--c-indigo) 100%);
  color: #fff;
  flex: none;
}

.brand__text { display: flex; flex-direction: column; line-height: 1.2; }
.brand__text strong { color: #fff; font-size: var(--fs-md); }
.brand__text small { color: var(--tx-on-dark-2); font-size: var(--fs-xs); }

.nav__toggle {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  width: 44px;
  height: 44px;
  border: 1px solid rgba(148, 163, 184, .35);
  border-radius: var(--radius-ctl);
  background: transparent;
  color: var(--tx-on-dark-1);
}

.nav__toggle-close { display: none; }
.nav--open ~ .nav__toggle .nav__toggle-close,
.topbar.is-open .nav__toggle-close { display: inline-block; }
.topbar.is-open .nav__toggle-open { display: none; }

.nav {
  position: absolute;
  left: 0;
  right: 0;
  top: 100%;
  background: rgba(15, 23, 42, .98);
  border-bottom: 1px solid rgba(148, 163, 184, .2);
  display: none;
}

.topbar.is-open .nav { display: block; }

.nav__list {
  list-style: none;
  margin: 0;
  padding: var(--sp-3) var(--sp-4) var(--sp-5);
}

.nav__item { margin: 0; position: relative; }

.nav__link,
.nav__sublink {
  display: block;
  padding: var(--sp-3) var(--sp-2);
  color: var(--tx-on-dark-2);
  border-radius: var(--radius-ctl);
  min-height: 44px;
  line-height: 1.5;
}

.nav__link:hover,
.nav__sublink:hover { color: #fff; background: rgba(59, 130, 246, .16); }

.nav__item--active > .nav__link {
  color: #fff;
  font-weight: 700;
  background: rgba(37, 99, 235, .28);
}

.nav__item--active > .nav__link::after {
  content: "";
  position: absolute;
  left: 8px;
  right: 8px;
  bottom: 2px;
  height: 2px;
  border-radius: 2px;
  background: var(--c-brand-2);
}

.nav__sub {
  list-style: none;
  margin: 0 0 var(--sp-2);
  padding: 0 0 0 var(--sp-4);
  border-left: 1px solid rgba(148, 163, 184, .28);
}

.nav__sublink { padding-block: var(--sp-2); font-size: var(--fs-sm); min-height: 40px; }
.nav__sublink.is-active { color: #fff; font-weight: 700; }

@media (min-width: 1024px) {
  .nav__toggle { display: none; }

  .nav {
    position: static;
    display: block;
    background: transparent;
    border: 0;
  }

  .nav__list {
    display: flex;
    align-items: center;
    gap: var(--sp-1);
    padding: 0;
  }

  .nav__link { padding: var(--sp-3); font-size: var(--fs-sm); white-space: nowrap; }

  .nav__item--has-sub:hover > .nav__link,
  .nav__item--has-sub:focus-within > .nav__link { color: #fff; }

  .nav__sub {
    position: absolute;
    left: 0;
    top: 100%;
    min-width: 180px;
    margin: 0;
    padding: var(--sp-2);
    background: rgba(15, 23, 42, .98);
    border: 1px solid rgba(148, 163, 184, .2);
    border-radius: var(--radius-card);
    box-shadow: var(--shadow-2);
    opacity: 0;
    visibility: hidden;
    transform: translateY(-6px);
    transition: opacity .16s ease, transform .16s ease;
  }

  .nav__item--has-sub:hover .nav__sub,
  .nav__item--has-sub:focus-within .nav__sub {
    opacity: 1;
    visibility: visible;
    transform: translateY(0);
  }
}

@media (min-width: 1440px) {
  .nav__link { font-size: var(--fs-base); }
}

/* ------------------------------ 面包屑 ------------------------------ */

.breadcrumb {
  padding-block: var(--sp-3);
  border-bottom: 1px solid rgba(148, 163, 184, .18);
  background: #fff;
}

.breadcrumb__list {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: var(--sp-2);
  list-style: none;
  margin: 0 auto;
  padding: 0;
  max-width: var(--container);
  font-size: var(--fs-sm);
  color: var(--tx-2);
}

.breadcrumb__item { margin: 0; display: inline-flex; align-items: center; gap: var(--sp-2); }

.breadcrumb__item + .breadcrumb__item::before {
  content: "/";
  color: var(--tx-3);
}

.breadcrumb__link { color: var(--tx-2); }
.breadcrumb__link:hover { color: var(--c-brand); }
.breadcrumb__item--current { color: var(--tx-1); font-weight: 600; }

/* ------------------------------ 页脚 ------------------------------ */

.footer {
  padding-block: var(--sp-7) var(--sp-5);
  background: var(--bg-dark);
  color: var(--tx-on-dark-2);
}

.footer__inner { max-width: var(--container); }

.footer__grid {
  display: grid;
  grid-template-columns: 1fr;
  gap: var(--sp-5);
}

@media (min-width: 640px) {
  .footer__grid { grid-template-columns: repeat(2, minmax(0, 1fr)); }
}

@media (min-width: 1024px) {
  .footer__grid { grid-template-columns: repeat(4, minmax(0, 1fr)); gap: var(--sp-6); }
}

.footer__title {
  margin-bottom: var(--sp-3);
  font-size: var(--fs-base);
  color: var(--tx-on-dark-1);
}

.footer__list { list-style: none; margin: 0; padding: 0; }
.footer__list li { margin-bottom: var(--sp-2); }

.footer__link { color: var(--tx-on-dark-2); font-size: var(--fs-sm); }
.footer__link:hover { color: #fff; }

.footer__plain { font-size: var(--fs-sm); color: var(--tx-on-dark-2); }
.footer__label { display: inline-block; margin-right: var(--sp-2); color: var(--tx-3); }

.footer__bottom {
  margin-top: var(--sp-6);
  padding-top: var(--sp-4);
  border-top: 1px solid rgba(148, 163, 184, .22);
}

.footer__note { margin-bottom: var(--sp-2); font-size: var(--fs-xs); color: var(--tx-3); }

.footer__meta {
  display: flex;
  flex-wrap: wrap;
  gap: var(--sp-4);
  margin: 0;
  font-size: var(--fs-xs);
  color: var(--tx-3);
}

/* ------------------------------ 吸底 CTA 条 ------------------------------ */

.cta-bar {
  position: fixed;
  left: 0;
  right: 0;
  bottom: 0;
  z-index: 60;
  background: rgba(15, 23, 42, .96);
  backdrop-filter: blur(12px);
  -webkit-backdrop-filter: blur(12px);
  border-top: 1px solid rgba(148, 163, 184, .22);
  box-shadow: 0 -6px 24px rgba(15, 23, 42, .18);
  transform: translateY(0);
  transition: transform .22s ease;
}

.cta-bar[hidden] { display: none; }

.cta-bar__inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: var(--sp-4);
  padding-block: var(--sp-3);
}

.cta-bar__text { margin: 0; font-size: var(--fs-sm); color: var(--tx-on-dark-2); }

.cta-bar__text strong {
  display: block;
  color: var(--tx-on-dark-1);
  font-size: var(--fs-base);
}

.cta-bar__text span { display: none; }

.cta-bar__actions { display: flex; align-items: center; gap: var(--sp-3); flex: none; }

.cta-bar__close {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  width: 44px;
  height: 44px;
  border: 1px solid rgba(148, 163, 184, .3);
  border-radius: var(--radius-ctl);
  background: transparent;
  color: var(--tx-on-dark-2);
}

@media (min-width: 640px) {
  .cta-bar__text span { display: block; }
}

/* ------------------------------ Hero 内部布局 ------------------------------ */

.hero__grid {
  display: grid;
  grid-template-columns: 1fr;
  gap: var(--sp-6);
}

@media (min-width: 1024px) {
  .hero__grid { grid-template-columns: minmax(0, 1.05fr) minmax(0, 1fr); align-items: start; }
}

.hero__eyebrow {
  display: inline-flex;
  align-items: center;
  gap: var(--sp-2);
  padding: 6px var(--sp-3);
  margin-bottom: var(--sp-4);
  font-size: var(--fs-xs);
  letter-spacing: .08em;
  color: var(--tx-on-dark-2);
  border: 1px solid rgba(148, 163, 184, .35);
  border-radius: var(--radius-badge);
}

.hero__sub { max-width: 640px; font-size: clamp(15px, 2vw, 19px); color: var(--tx-on-dark-2); }

.hero__note { font-size: var(--fs-sm); color: var(--tx-on-dark-2); }

.hero__actions {
  display: flex;
  flex-wrap: wrap;
  gap: var(--sp-3);
  margin-top: var(--sp-5);
}