/**
 * 全宽 Mega Menu（华为式）+ Pure Flat 首屏
 * 生产稿 site-v2
 */

/* 首屏：纯白 / 无雾无纹 */
.hero-bg {
  background: #ffffff;
}

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

/* 关闭旧下拉（若残留） */
.submenu {
  display: none !important;
}

.site-header {
  overflow: visible;
  position: sticky;
  z-index: 100;
}

.nav-item.has-mega {
  position: relative;
  display: flex;
  align-items: stretch;
}

.nav-item.has-mega > .nav-trigger {
  position: relative;
  display: flex;
  align-items: center;
  height: 100%;
  padding: 0;
  border: 0;
  background: transparent;
  font: inherit;
  font-weight: 500;
  color: inherit;
  cursor: pointer;
}

.nav-item.has-mega.is-active > .nav-trigger,
.nav-item.has-mega:hover > .nav-trigger {
  color: var(--cyan);
}

/* 标题栏底缘品牌色下划线 */
.nav-item.has-mega > .nav-trigger::after {
  content: "";
  position: absolute;
  left: 0;
  right: 0;
  bottom: 0;
  height: 3px;
  background: var(--cyan);
  transform: scaleX(0);
  transition: transform 0.18s ease;
}

.nav-item.has-mega.is-active > .nav-trigger::after {
  transform: scaleX(1);
}

/* 全宽面板：贴齐 Header 下缘 */
.mega-panel {
  position: absolute;
  left: 0;
  right: 0;
  top: 100%;
  display: none;
  background: var(--white);
  border-top: 1px solid var(--line);
  box-shadow: 0 18px 40px rgba(15, 23, 42, 0.1);
  z-index: 90;
}

.mega-panel.is-open {
  display: block;
}

.mega-inner {
  position: relative;
  width: min(100%, var(--max));
  margin: 0 auto;
  padding: 2rem clamp(1.25rem, 4vw, 3rem) 2.25rem;
}

.mega-close {
  position: absolute;
  top: 1rem;
  right: clamp(1.25rem, 4vw, 3rem);
  width: 36px;
  height: 36px;
  border: 0;
  background: transparent;
  font-size: 1.5rem;
  line-height: 1;
  color: var(--muted);
  cursor: pointer;
}

.mega-close:hover {
  color: var(--navy);
}

.mega-cols {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 0;
}

.mega-col {
  display: block;
  padding: 0.5rem 1.75rem 0.5rem 0;
  color: inherit;
  transition: background 0.15s ease;
}

.mega-col + .mega-col {
  padding-left: 1.75rem;
  border-left: 1px solid var(--line);
}

.mega-label {
  margin: 0 0 0.65rem;
  font-size: 0.8125rem;
  font-weight: 600;
  letter-spacing: 0.06em;
  color: var(--cyan);
}

.mega-col h3 {
  margin: 0 0 0.5rem;
  font-size: 1.125rem;
  font-weight: 700;
  color: var(--navy);
}

.mega-col p {
  margin: 0;
  font-size: 0.875rem;
  line-height: 1.55;
  color: var(--muted);
}

.mega-col:hover h3 {
  color: var(--cyan);
}

.mega-foot {
  background: var(--soft);
  border-top: 1px solid var(--line);
}

.mega-foot-inner {
  width: min(100%, var(--max));
  margin: 0 auto;
  padding: 0.9rem clamp(1.25rem, 4vw, 3rem);
  display: flex;
  flex-wrap: wrap;
  gap: 1.5rem;
}

.mega-foot a {
  font-size: 0.875rem;
  font-weight: 500;
  color: var(--navy);
}

.mega-foot a:hover {
  color: var(--cyan);
}

.mega-backdrop {
  position: fixed;
  inset: 0;
  top: var(--header-h);
  background: rgba(11, 31, 58, 0.28);
  opacity: 0;
  pointer-events: none;
  transition: opacity 0.2s ease;
  z-index: 80;
}

.mega-backdrop.is-open {
  opacity: 1;
  pointer-events: auto;
}

@media (max-width: 960px) {
  .mega-panel,
  .mega-backdrop {
    display: none !important;
  }

  .nav-item.has-mega > .nav-trigger {
    height: auto;
    width: 100%;
    justify-content: flex-start;
    padding: 0.85rem 0;
    border-bottom: 1px solid var(--line);
  }

  .nav-item.has-mega > .nav-trigger::after {
    display: none;
  }
}