:root {
  --black: #030303;
  --black-soft: #0c0c0e;
  --white: #f2f2f0;
  --white-dim: rgba(242, 242, 240, 0.72);
  --white-faint: rgba(242, 242, 240, 0.38);
  --accent: #7dd3fc;
  --accent-dim: rgba(125, 211, 252, 0.35);
  --font-display: "Orbitron", system-ui, sans-serif;
  --font-body: "Noto Sans SC", "PingFang SC", system-ui, sans-serif;
  --ease: cubic-bezier(0.16, 1, 0.3, 1);
  --header-h: 5.5rem;
}

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

html {
  scroll-behavior: smooth;
}

body {
  margin: 0;
  color: var(--white);
  font-family: var(--font-body);
  font-weight: 300;
  line-height: 1.85;
  background: var(--black);
  overflow-x: hidden;
}

/* —— 全屏视频 —— */
.viewport-bg {
  position: fixed;
  inset: 0;
  z-index: -1;
  overflow: hidden;
  background: var(--black);
}

.bg-video {
  position: absolute;
  inset: 0;
  width: 100%;
  height: 100%;
  object-fit: cover;
  object-position: center center;
  filter: grayscale(1) contrast(1.06) brightness(0.62);
  opacity: 0;
  transition:
    opacity 0.8s var(--ease),
    filter 0.6s var(--ease);
}

body.is-video-ready .bg-video {
  opacity: 1;
}

/* 元数据就绪后由 JS 精确控制：仅一边 100%，另一边溢出裁切 */
.bg-video.is-sized {
  inset: auto;
  top: 50%;
  left: 50%;
  transform: translate(-50%, -50%);
  width: auto;
  height: auto;
  object-fit: none;
}

body.is-scrolled .bg-video {
  filter: grayscale(1) contrast(1.04) brightness(0.42);
}

.bg-dim {
  position: absolute;
  inset: 0;
  background: linear-gradient(
    180deg,
    rgba(3, 3, 3, 0.12) 0%,
    rgba(3, 3, 3, 0.06) 35%,
    rgba(3, 3, 3, 0.28) 70%,
    rgba(3, 3, 3, 0.62) 100%
  );
  opacity: 0.32;
  transition: opacity 0.7s var(--ease);
  pointer-events: none;
}

body.is-scrolled .bg-dim {
  opacity: 0.72;
}

/* —— 视频加载层 —— */
.video-loader {
  position: fixed;
  inset: 0;
  z-index: 200;
  display: flex;
  align-items: center;
  justify-content: center;
  background: var(--black);
  transition:
    opacity 0.65s var(--ease),
    visibility 0.65s;
}

/* 二次访问：本地已有缓存标记，缩短加载层存在感 */
html.has-video-cache .video-loader {
  background: rgba(3, 3, 3, 0.92);
}

html.has-video-cache .video-loader:not(.is-done) .video-loader-logo {
  animation: none;
}

.video-loader.is-done {
  opacity: 0;
  visibility: hidden;
  pointer-events: none;
}

.video-loader-panel {
  width: min(280px, 78vw);
  text-align: center;
}

.video-loader-logo {
  width: 64px;
  height: 64px;
  border-radius: 50%;
  object-fit: cover;
  border: 1px solid rgba(255, 255, 255, 0.2);
  margin-bottom: 1.25rem;
  animation: loader-pulse 2s ease-in-out infinite;
}

@keyframes loader-pulse {
  0%,
  100% {
    box-shadow: 0 0 0 0 rgba(125, 211, 252, 0.25);
  }
  50% {
    box-shadow: 0 0 28px 4px rgba(125, 211, 252, 0.2);
  }
}

.video-loader-label {
  margin: 0 0 1rem;
  font-family: var(--font-display);
  font-size: 0.58rem;
  letter-spacing: 0.4em;
  color: var(--white-faint);
}

.video-loader-track {
  height: 2px;
  background: rgba(255, 255, 255, 0.1);
  border-radius: 1px;
  overflow: hidden;
}

.video-loader-bar {
  height: 100%;
  width: 0%;
  background: linear-gradient(90deg, rgba(255, 255, 255, 0.5), var(--accent));
  border-radius: 1px;
  transition: width 0.15s linear;
}

.video-loader-pct {
  margin: 0.65rem 0 0;
  font-family: var(--font-display);
  font-size: 0.72rem;
  letter-spacing: 0.2em;
  color: var(--white-dim);
}

body.is-video-loading .gate-inner {
  visibility: hidden;
}

.bg-noise {
  position: absolute;
  inset: 0;
  opacity: 0.22;
  pointer-events: none;
  background-image: url("data:image/svg+xml,%3Csvg viewBox='0 0 200 200' xmlns='http://www.w3.org/2000/svg'%3E%3Cfilter id='n'%3E%3CfeTurbulence type='fractalNoise' baseFrequency='0.9' numOctaves='3'/%3E%3C/filter%3E%3Crect width='100%25' height='100%25' filter='url(%23n)'/%3E%3C/svg%3E");
  mix-blend-mode: overlay;
}

/* —— 左上角品牌 —— */
.identity {
  position: fixed;
  top: 1.35rem;
  left: 1.35rem;
  z-index: 100;
  display: flex;
  align-items: center;
  gap: 0.85rem;
  text-decoration: none;
  color: inherit;
  transition: opacity 0.3s;
}

.identity:hover {
  opacity: 0.85;
}

.identity-logo {
  width: 52px;
  height: 52px;
  border-radius: 50%;
  object-fit: cover;
  border: 1px solid rgba(255, 255, 255, 0.25);
  box-shadow:
    0 0 24px var(--accent-dim),
    0 0 0 1px rgba(0, 0, 0, 0.5);
}

.identity-text {
  display: flex;
  flex-direction: column;
  gap: 0.1rem;
}

.identity-cn {
  font-family: var(--font-display);
  font-size: 1rem;
  font-weight: 700;
  letter-spacing: 0.2em;
  color: var(--white);
  text-shadow: 0 0 20px var(--accent-dim);
}

.identity-en {
  font-family: var(--font-display);
  font-size: 0.62rem;
  font-weight: 500;
  letter-spacing: 0.35em;
  text-transform: uppercase;
  color: var(--white-faint);
}

/* —— 右侧锚点导航 —— */
.side-nav {
  position: fixed;
  right: 1.25rem;
  top: 50%;
  transform: translateY(-50%);
  z-index: 90;
  display: flex;
  flex-direction: column;
  gap: 1.1rem;
}

.side-nav a {
  position: relative;
  display: block;
  width: 6px;
  height: 6px;
  border-radius: 50%;
  background: var(--white-faint);
  text-decoration: none;
  transition:
    background 0.3s,
    transform 0.3s,
    box-shadow 0.3s;
}

.side-nav a::after {
  content: attr(data-label);
  position: absolute;
  right: 1rem;
  top: 50%;
  transform: translateY(-50%);
  font-family: var(--font-display);
  font-size: 0.55rem;
  letter-spacing: 0.2em;
  color: var(--white);
  opacity: 0;
  pointer-events: none;
  transition: opacity 0.25s, right 0.25s;
  white-space: nowrap;
}

.side-nav a:hover,
.side-nav a.is-active {
  background: var(--white);
  transform: scale(1.35);
  box-shadow: 0 0 12px var(--accent-dim);
}

.side-nav a:hover::after {
  opacity: 1;
  right: 1.15rem;
}

@media (max-width: 720px) {
  .side-nav {
    display: none;
  }
}

/* —— 首屏门厅（纯视频区） —— */
.gate {
  position: relative;
  min-height: 100vh;
  min-height: 100dvh;
  display: flex;
  align-items: flex-end;
  justify-content: flex-start;
  padding: 0 1.5rem 4rem;
  padding-left: max(1.5rem, 12vw);
}

.gate-inner {
  max-width: 42rem;
  opacity: 0;
  transform: translateY(28px);
  animation: gate-in 1.2s var(--ease) 0.35s forwards;
}

@keyframes gate-in {
  to {
    opacity: 1;
    transform: translateY(0);
  }
}

.gate-tag {
  margin: 0 0 1rem;
  font-family: var(--font-display);
  font-size: 0.65rem;
  font-weight: 500;
  letter-spacing: 0.45em;
  color: var(--white-faint);
}

.gate-title {
  margin: 0;
  font-family: var(--font-display);
  font-weight: 900;
  line-height: 1.05;
}

.gate-line {
  display: block;
  font-size: clamp(2.2rem, 8vw, 4.2rem);
  letter-spacing: 0.06em;
  color: var(--white);
  text-shadow: 0 0 60px rgba(255, 255, 255, 0.15);
}

.gate-line--ghost {
  -webkit-text-stroke: 1px rgba(242, 242, 240, 0.85);
  color: transparent;
  margin-top: 0.15em;
}

.gate-scroll {
  display: flex;
  align-items: center;
  gap: 0.75rem;
  margin: 2.5rem 0 0;
  font-family: var(--font-display);
  font-size: 0.58rem;
  letter-spacing: 0.3em;
  color: var(--white-faint);
}

.gate-scroll-bar {
  display: block;
  width: 1px;
  height: 48px;
  background: linear-gradient(180deg, var(--white), transparent);
  animation: pulse-bar 2.2s ease-in-out infinite;
}

@keyframes pulse-bar {
  0%,
  100% {
    opacity: 0.35;
    transform: scaleY(0.65);
  }
  50% {
    opacity: 1;
    transform: scaleY(1);
  }
}

/* —— 下滑内容区：渐变显现，无卡片 —— */
.content-flow {
  position: relative;
  padding-bottom: 4rem;
}

.content-flow::before {
  content: "";
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  height: 18vh;
  background: linear-gradient(180deg, transparent, var(--black-soft));
  pointer-events: none;
  transform: translateY(-100%);
}

.flow-section {
  position: relative;
  max-width: 52rem;
  margin: 0 auto;
  padding: clamp(4rem, 12vh, 7rem) 1.5rem 0;
  opacity: 0;
  transform: translateY(48px);
  transition:
    opacity 1s var(--ease),
    transform 1s var(--ease);
}

.flow-section.is-visible {
  opacity: 1;
  transform: translateY(0);
}

.flow-section::after {
  content: "";
  display: block;
  margin-top: clamp(3rem, 8vh, 5rem);
  height: 1px;
  background: linear-gradient(
    90deg,
    transparent,
    rgba(255, 255, 255, 0.12) 20%,
    rgba(255, 255, 255, 0.12) 80%,
    transparent
  );
}

.flow-section--end::after {
  display: none;
}

.flow-label {
  margin: 0 0 0.75rem;
  font-family: var(--font-display);
  font-size: 0.62rem;
  font-weight: 500;
  letter-spacing: 0.4em;
  color: var(--accent);
  opacity: 0.85;
}

.flow-heading {
  margin: 0 0 1.75rem;
  font-family: var(--font-display);
  font-size: clamp(1.6rem, 4.5vw, 2.4rem);
  font-weight: 700;
  letter-spacing: 0.08em;
  line-height: 1.2;
}

.flow-body {
  font-size: 1.05rem;
  color: var(--white-dim);
}

.flow-body--wide {
  max-width: 40rem;
}

.flow-body p {
  margin: 0 0 1.25rem;
}

.flow-body em {
  font-style: normal;
  color: var(--white);
  border-bottom: 1px solid var(--accent-dim);
}

.flow-body strong {
  font-weight: 500;
  color: var(--white);
}

/* 数据条 */
.flow-stats {
  display: flex;
  flex-wrap: wrap;
  gap: 2.5rem 3.5rem;
  margin: 2.5rem 0 0;
  padding: 0;
  list-style: none;
}

.flow-stats li {
  display: flex;
  flex-direction: column;
  gap: 0.35rem;
}

.flow-stats strong {
  font-family: var(--font-display);
  font-size: clamp(1.8rem, 4vw, 2.5rem);
  font-weight: 700;
  letter-spacing: 0.05em;
  color: var(--white);
  line-height: 1;
}

.flow-stats span {
  font-size: 0.82rem;
  color: var(--white-faint);
  letter-spacing: 0.08em;
}

/* 技能流 */
.skill-river {
  display: flex;
  flex-wrap: wrap;
  gap: 0.5rem 0.65rem;
  margin: 2rem 0 2.5rem;
}

.skill-river span {
  font-family: var(--font-display);
  font-size: 0.62rem;
  letter-spacing: 0.12em;
  padding: 0.35rem 0.75rem;
  border: 1px solid rgba(255, 255, 255, 0.12);
  color: var(--white-dim);
  transition:
    border-color 0.3s,
    color 0.3s,
    box-shadow 0.3s;
}

.skill-river span:hover {
  border-color: var(--accent-dim);
  color: var(--white);
  box-shadow: 0 0 20px var(--accent-dim);
}

.flow-columns {
  display: grid;
  gap: 2rem;
  margin-top: 1rem;
}

@media (min-width: 720px) {
  .flow-columns {
    grid-template-columns: repeat(3, 1fr);
    gap: 2.5rem;
  }
}

.flow-col h3 {
  margin: 0 0 0.6rem;
  font-family: var(--font-display);
  font-size: 0.72rem;
  font-weight: 700;
  letter-spacing: 0.25em;
  color: var(--white);
}

.flow-col p {
  margin: 0;
  font-size: 0.92rem;
  color: var(--white-faint);
  line-height: 1.75;
}

/* 引用 */
.flow-quote {
  margin: 2.5rem 0;
  padding-left: 1.25rem;
  border-left: 2px solid var(--accent-dim);
  font-family: var(--font-display);
  font-size: clamp(1rem, 2.5vw, 1.25rem);
  font-weight: 500;
  letter-spacing: 0.06em;
  color: var(--white);
  font-style: normal;
}

.game-list {
  margin: 1.5rem 0 0;
  padding: 0;
  list-style: none;
  display: grid;
  gap: 0.85rem;
}

@media (min-width: 600px) {
  .game-list {
    grid-template-columns: 1fr 1fr;
  }
}

.game-list li {
  font-size: 0.95rem;
  color: var(--white-dim);
  padding-left: 1rem;
  position: relative;
}

.game-list li::before {
  content: "▸";
  position: absolute;
  left: 0;
  color: var(--accent);
  font-size: 0.7rem;
}

/* 时间线 */
.timeline {
  margin-top: 2rem;
  border-left: 1px solid rgba(255, 255, 255, 0.1);
  padding-left: 1.5rem;
}

.timeline-item {
  position: relative;
  padding-bottom: 1.75rem;
}

.timeline-item:last-child {
  padding-bottom: 0;
}

.timeline-item::before {
  content: "";
  position: absolute;
  left: -1.5rem;
  top: 0.55rem;
  width: 7px;
  height: 7px;
  margin-left: -3px;
  border-radius: 50%;
  background: var(--white);
  box-shadow: 0 0 12px var(--accent-dim);
}

.timeline-item time {
  display: block;
  font-family: var(--font-display);
  font-size: 0.62rem;
  letter-spacing: 0.3em;
  color: var(--accent);
  margin-bottom: 0.35rem;
}

.timeline-item p {
  margin: 0;
  font-size: 0.95rem;
  color: var(--white-dim);
}

/* 联系 */
.flow-contact-lead {
  max-width: 28rem;
  margin-bottom: 2rem !important;
}

.contact-strip {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 1rem 1.5rem;
  margin-bottom: 4rem;
}

.contact-link {
  font-family: var(--font-display);
  font-size: 0.85rem;
  letter-spacing: 0.12em;
  color: var(--white);
  text-decoration: none;
  border-bottom: 1px solid var(--white-faint);
  padding-bottom: 0.2rem;
  transition: border-color 0.3s, text-shadow 0.3s;
}

.contact-link:hover {
  border-color: var(--accent);
  text-shadow: 0 0 24px var(--accent-dim);
}

.contact-divider {
  width: 32px;
  height: 1px;
  background: rgba(255, 255, 255, 0.15);
}

.contact-meta {
  font-size: 0.82rem;
  color: var(--white-faint);
  letter-spacing: 0.1em;
}

.site-foot {
  padding-top: 2rem;
  border-top: 1px solid rgba(255, 255, 255, 0.08);
}

.site-foot p {
  margin: 0;
  font-family: var(--font-display);
  font-size: 0.58rem;
  letter-spacing: 0.25em;
  color: var(--white-faint);
  text-transform: uppercase;
}

@media (prefers-reduced-motion: reduce) {
  html {
    scroll-behavior: auto;
  }

  .gate-inner,
  .gate-scroll-bar,
  .flow-section,
  .bg-video,
  .bg-dim,
  .video-loader-logo {
    animation: none;
    transition: none;
  }

  .video-loader.is-done {
    display: none;
  }

  .gate-inner,
  .flow-section {
    opacity: 1;
    transform: none;
  }
}

@media (max-width: 480px) {
  .identity-logo {
    width: 44px;
    height: 44px;
  }

  .identity-cn {
    font-size: 0.9rem;
  }

  .gate {
    padding-left: 1.25rem;
    padding-bottom: 3rem;
  }
}