/* ============================================================
   亿渼诺 YIMEINUO · 布局 Layout：导航 / 首屏 / 板块骨架
   ============================================================ */

/* ---- 顶部导航（极简） ---- */
.nav {
  position: fixed;
  inset: 0 0 auto 0;
  z-index: var(--z-nav);
  padding: 22px 0;
  border-bottom: 1px solid transparent;
  transition:
    background 0.45s var(--ease),
    padding 0.45s var(--ease),
    border-color 0.45s var(--ease);
}
.nav.is-scrolled {
  background: rgba(14, 13, 11, 0.82);
  -webkit-backdrop-filter: blur(14px);
  backdrop-filter: blur(14px);
  padding: 12px 0;
  border-bottom-color: var(--color-line);
}
.nav__inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 24px;
}

.brand {
  display: flex;
  align-items: baseline;
  gap: 12px;
  white-space: nowrap;
}
.brand__cn {
  font-family: var(--font-serif);
  font-size: 21px;
  letter-spacing: var(--ls-cn);
}
.brand__en {
  font-family: var(--font-latin);
  font-size: 10px;
  letter-spacing: 0.34em;
  text-transform: uppercase;
  color: var(--color-ink-3);
}

.nav__links {
  display: flex;
  align-items: center;
  gap: 36px;
}
.nav__links a {
  position: relative;
  font-size: 12px;
  letter-spacing: 0.22em;
  color: var(--color-ink-2);
  transition: color 0.3s;
}
.nav__links a::after {
  content: "";
  position: absolute;
  left: 0;
  bottom: -6px;
  width: 100%;
  height: 1px;
  background: var(--color-accent);
  transform: scaleX(0);
  transform-origin: right;
  transition: transform 0.45s var(--ease);
}
.nav__links a:hover,
.nav__links a.is-active {
  color: var(--color-ink);
}
.nav__links a:hover::after,
.nav__links a.is-active::after {
  transform: scaleX(1);
  transform-origin: left;
}

/* 汉堡按钮（移动端） */
.nav__toggle {
  display: none;
  flex-direction: column;
  justify-content: center;
  gap: 7px;
  width: 44px;
  height: 44px;
  align-items: center;
}
.nav__toggle span {
  display: block;
  width: 26px;
  height: 1px;
  background: var(--color-ink);
  transition: transform 0.4s var(--ease), opacity 0.3s;
}
.menu-open .nav__toggle span:nth-child(1) { transform: translateY(4px) rotate(45deg); }
.menu-open .nav__toggle span:nth-child(2) { transform: translateY(-4px) rotate(-45deg); }

/* 移动端全屏菜单 */
.menu {
  position: fixed;
  inset: 0;
  z-index: calc(var(--z-nav) - 1);
  background: var(--color-bg);
  display: flex;
  flex-direction: column;
  justify-content: center;
  padding: 96px var(--pad-x) 48px;
  transform: translateY(-100%);
  visibility: hidden;
  transition:
    transform 0.6s var(--ease),
    visibility 0s 0.6s;
}
.menu-open .menu {
  transform: none;
  visibility: visible;
  transition:
    transform 0.6s var(--ease),
    visibility 0s;
}
.menu a {
  font-family: var(--font-serif);
  font-size: clamp(30px, 7vw, 44px);
  letter-spacing: var(--ls-cn);
  padding: 14px 0;
  border-bottom: 1px solid var(--color-line);
  display: flex;
  justify-content: space-between;
  align-items: baseline;
}
.menu a small {
  font-family: var(--font-sans);
  font-size: 11px;
  letter-spacing: 0.28em;
  color: var(--color-ink-3);
}
.menu .menu__foot {
  margin-top: 40px;
  display: flex;
  justify-content: space-between;
  font-size: 12px;
  letter-spacing: 0.2em;
  color: var(--color-ink-3);
}

/* ---- 首屏 Hero（SoftAurora 动态背景 + 居中文字） ---- */
.hero {
  position: relative;
  min-height: 100vh;
  min-height: 100svh;
  display: flex;
  align-items: center;
  justify-content: center;
  overflow: hidden;
}
.hero__aurora {
  position: absolute;
  inset: 0;
  width: 100%;
  height: 100%;
  z-index: 0;
}
/* 柔光罩：压低背景亮度，保证文字对比度 */
.hero::after {
  content: "";
  position: absolute;
  inset: 0;
  z-index: 0;
  pointer-events: none;
  background:
    radial-gradient(ellipse 90% 70% at 50% 42%, rgba(14, 13, 11, 0) 30%, rgba(14, 13, 11, 0.5) 100%);
}
.hero__inner {
  z-index: 1;
  text-align: center;
  padding-top: 120px;
  padding-bottom: 96px;
}

/* WebGL 不可用 / 软件渲染时的极简 CSS 光晕兜底（近乎零开销的 GPU 合成动画） */
.aurora-css .hero {
  background:
    radial-gradient(ellipse 62% 46% at 50% 36%, rgba(237, 230, 218, 0.10), transparent 62%),
    radial-gradient(ellipse 58% 42% at 66% 62%, rgba(196, 167, 149, 0.08), transparent 60%),
    var(--color-bg);
  background-size: 160% 160%, 160% 160%, auto;
  animation: auroraShift 16s ease-in-out infinite alternate;
}
@keyframes auroraShift {
  from { background-position: 0% 0%, 100% 100%; }
  to   { background-position: 42% 30%, 60% 68%; }
}
.hero__label {
  margin-bottom: 30px;
}
.hero__title {
  font-size: clamp(48px, 8.4vw, 104px);
  font-weight: 400;
  letter-spacing: var(--ls-cn);
  line-height: 1.18;
  text-shadow: 0 2px 32px rgba(0, 0, 0, 0.35);
}
.hero__sub {
  margin: 32px auto 0;
  max-width: 30em;
  font-size: 15px;
  color: var(--color-ink-2);
  text-shadow: 0 1px 20px rgba(0, 0, 0, 0.4);
}
.hero__cta {
  margin-top: 44px;
  display: flex;
  justify-content: center;
  flex-wrap: wrap;
  gap: 16px;
}
.hero__meta {
  margin-top: clamp(56px, 10vh, 110px);
  padding-top: 22px;
  border-top: 1px solid var(--color-line);
  display: flex;
  justify-content: space-between;
  flex-wrap: wrap;
  gap: 10px 24px;
  font-size: 11px;
  letter-spacing: 0.22em;
  color: var(--color-ink-3);
}

/* ---- 板块氛围光层（进入视口时淡入，增强层次感） ---- */
.section__glow {
  position: absolute;
  top: 0;
  left: 50%;
  transform: translateX(-50%);
  width: 120%;
  height: 100%;
  pointer-events: none;
  z-index: 0;
  background:
    radial-gradient(ellipse 70% 46% at 50% 8%, rgba(181, 164, 138, 0.06), transparent 70%),
    radial-gradient(ellipse 50% 40% at 82% 92%, rgba(196, 167, 149, 0.04), transparent 70%);
  opacity: 0;
  transition: opacity 1.4s var(--ease);
}
.section.is-inview .section__glow {
  opacity: 1;
}