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

html {
  -webkit-text-size-adjust: 100%;
  overflow-x: hidden;
}

body {
  margin: 0;
  min-height: 100vh;
  overflow-x: hidden;
  background-color: var(--color-midnight);
  background-image:
    repeating-linear-gradient(45deg, rgba(212, 175, 55, 0.055) 0 1px, transparent 1px 80px),
    repeating-linear-gradient(-45deg, rgba(212, 175, 55, 0.055) 0 1px, transparent 1px 80px);
  color: var(--color-ivory);
  font-family: var(--font-serif);
  font-size: var(--text-body);
  line-height: 1.7;
  -webkit-font-smoothing: antialiased;
}

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

a {
  color: inherit;
}

::selection {
  background: rgba(212, 175, 55, 0.3);
  color: #fff;
}

:focus-visible {
  outline: 1px solid var(--color-gold);
  outline-offset: 4px;
}

/* 页面四角金线框 */
.page-frame {
  position: fixed;
  inset: 16px;
  border: 1px solid var(--line-gold-soft);
  pointer-events: none;
  z-index: 5;
}

.page-frame::before {
  content: "";
  position: absolute;
  inset: 8px;
  border: 1px solid rgba(212, 175, 55, 0.44);
}

.page-frame__tick {
  position: absolute;
  width: 14px;
  height: 1px;
  background: var(--line-gold-strong);
}

.page-frame__tick--tl {
  top: -1px;
  left: -1px;
  transform-origin: left center;
  transform: rotate(45deg);
}

.page-frame__tick--tr {
  top: -1px;
  right: -1px;
  transform-origin: right center;
  transform: rotate(-45deg);
}

.page-frame__tick--bl {
  bottom: -1px;
  left: -1px;
  transform-origin: left center;
  transform: rotate(-45deg);
}

.page-frame__tick--br {
  bottom: -1px;
  right: -1px;
  transform-origin: right center;
  transform: rotate(45deg);
}

/* 两侧环境动效：金线刻度、缓行光带、菱形节点 */
.ambient {
  position: fixed;
  inset: 0;
  z-index: 0;
  overflow: hidden;
  pointer-events: none;
}

.ambient__rail {
  position: absolute;
  top: 0;
  bottom: 0;
  width: 1px;
  background: linear-gradient(
    180deg,
    transparent,
    rgba(212, 175, 55, 0.22) 10%,
    rgba(212, 175, 55, 0.22) 90%,
    transparent
  );
}

.ambient__rail--left {
  left: clamp(20px, 3.4vw, 44px);
}

.ambient__rail--right {
  right: clamp(20px, 3.4vw, 44px);
}

/* 细密横向刻度，让竖线有柱式节奏 */
.ambient__rail::before {
  content: "";
  position: absolute;
  top: 0;
  bottom: 0;
  left: -4px;
  width: 9px;
  background-image: repeating-linear-gradient(
    180deg,
    rgba(212, 175, 55, 0.5) 0 1px,
    transparent 1px 64px
  );
  opacity: 0.32;
  -webkit-mask-image: linear-gradient(180deg, transparent, #000 14%, #000 86%, transparent);
  mask-image: linear-gradient(180deg, transparent, #000 14%, #000 86%, transparent);
}

/* 沿轨缓行的光带 */
.ambient__beam {
  position: absolute;
  top: 0;
  left: 0;
  width: 1px;
  height: clamp(120px, 18vh, 220px);
  background: linear-gradient(
    180deg,
    transparent,
    rgba(232, 201, 84, 0.85) 50%,
    transparent
  );
  box-shadow: 0 0 8px rgba(212, 175, 55, 0.35);
  animation: ambient-drift 12s linear infinite;
}

.ambient__rail--right .ambient__beam {
  animation-delay: -6s;
}

/* 菱形节点错峰明灭 */
.ambient__node {
  position: absolute;
  left: -4px;
  width: 9px;
  height: 9px;
  background: var(--color-midnight);
  border: 1px solid rgba(212, 175, 55, 0.55);
  box-shadow: 0 0 8px rgba(212, 175, 55, 0.25);
  transform: rotate(45deg);
  opacity: 0.2;
  animation: ambient-node 9s ease-in-out infinite;
}

.ambient__node:nth-child(2) {
  top: 16%;
  animation-delay: 0s;
}

.ambient__node:nth-child(3) {
  top: 32%;
  animation-delay: 0.9s;
}

.ambient__node:nth-child(4) {
  top: 48%;
  animation-delay: 1.8s;
}

.ambient__node:nth-child(5) {
  top: 64%;
  animation-delay: 2.7s;
}

.ambient__node:nth-child(6) {
  top: 80%;
  animation-delay: 3.6s;
}

@keyframes ambient-drift {
  0% {
    transform: translateY(-18vh);
    opacity: 0;
  }
  6% {
    opacity: 0.85;
  }
  94% {
    opacity: 0.85;
  }
  100% {
    transform: translateY(104vh);
    opacity: 0;
  }
}

@keyframes ambient-node {
  0%,
  100% {
    opacity: 0.18;
  }
  50% {
    opacity: 0.72;
  }
}

/* 窄屏：光带改沿页面金框运行，手机也能看见 */
@media (max-width: 1200px) {
  .ambient {
    z-index: 6;
  }

  .ambient__rail--left {
    left: 16px;
  }

  .ambient__rail--right {
    right: 16px;
  }

  .ambient__beam {
    height: 96px;
  }

  .ambient__node {
    left: -3px;
    width: 7px;
    height: 7px;
  }

  .ambient__rail::before {
    left: -3px;
    width: 7px;
    opacity: 0.22;
  }
}

@media (max-width: 480px) {
  .ambient__rail--left {
    left: 10px;
  }

  .ambient__rail--right {
    right: 10px;
  }
}

/* 放射分隔 */
.sunburst {
  color: rgba(212, 175, 55, 0.72);
}

.sunburst--inverted {
  transform: rotate(180deg);
}

/* 顶部小字 */
.eyebrow {
  display: flex;
  align-items: center;
  justify-content: center;
  gap: var(--spacing-16);
  margin: 0;
  color: var(--color-gold);
  font-family: var(--font-display);
  font-size: var(--text-label);
  letter-spacing: 0.2em;
  text-transform: uppercase;
}

.eyebrow__rule {
  display: block;
  width: clamp(32px, 10vw, 96px);
  height: 1px;
  background: var(--line-gold);
}

.visually-hidden {
  position: absolute;
  width: 1px;
  height: 1px;
  margin: -1px;
  padding: 0;
  overflow: hidden;
  clip: rect(0 0 0 0);
  white-space: nowrap;
  border: 0;
}

.skip-link {
  position: absolute;
  top: 0;
  left: 50%;
  z-index: 20;
  padding: 10px 24px;
  background: var(--color-midnight);
  color: var(--color-gold);
  border: 1px solid var(--color-gold);
  font-size: var(--text-label);
  letter-spacing: 0.2em;
  transform: translate(-50%, -120%);
}

.skip-link:focus {
  transform: translate(-50%, 12px);
}

@media (prefers-reduced-motion: reduce) {
  *,
  *::before,
  *::after {
    animation-duration: 0.001ms !important;
    animation-iteration-count: 1 !important;
    transition-duration: 0.001ms !important;
    scroll-behavior: auto !important;
  }
}