:root {
  --blue: #53c7ea;
  --blue-deep: #167aa5;
  --mint: #bff4d7;
  --mint-strong: #56d7a0;
  --yellow: #ffe98a;
  --pink: #ffb7c9;
  --ink: #173040;
  --muted: #5e7480;
  --paper: #fffdf5;
  --white: #ffffff;
  --glass: rgba(255, 255, 255, 0.72);
  --shadow: 0 22px 60px rgba(45, 124, 160, 0.16);
  --soft-shadow: 0 16px 42px rgba(39, 107, 140, 0.12);
  --radius-lg: 20px;
  --radius-md: 16px;
  --max: 1180px;
}

* {
  box-sizing: border-box;
}

html {
  scroll-behavior: smooth;
}

body {
  margin: 0;
  color: var(--ink);
  background:
    radial-gradient(circle at 15% 10%, rgba(255, 233, 138, 0.36), transparent 28rem),
    radial-gradient(circle at 90% 8%, rgba(191, 244, 215, 0.42), transparent 32rem),
    linear-gradient(180deg, #eefcff 0%, #fffdf5 46%, #f2fff7 100%);
  font-family: "Microsoft YaHei", "PingFang SC", "Hiragino Sans GB", system-ui, -apple-system, BlinkMacSystemFont, "Segoe UI", sans-serif;
  line-height: 1.75;
  overflow-x: hidden;
}

body.nav-open {
  overflow: hidden;
}

a {
  color: inherit;
  text-decoration: none;
}

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

.skip-link {
  position: absolute;
  left: 16px;
  top: -60px;
  z-index: 100;
  padding: 10px 14px;
  border-radius: 10px;
  background: var(--ink);
  color: var(--white);
  transition: top 0.2s ease;
}

.skip-link:focus {
  top: 16px;
}

.site-header {
  position: fixed;
  inset: 18px 24px auto;
  z-index: 20;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 18px;
  max-width: calc(var(--max) + 48px);
  margin: 0 auto;
  padding: 10px 12px 10px 16px;
  border: 1px solid rgba(255, 255, 255, 0.68);
  border-radius: var(--radius-lg);
  background: rgba(255, 255, 255, 0.66);
  box-shadow: 0 14px 42px rgba(23, 86, 112, 0.12);
  backdrop-filter: blur(14px);
}

.site-header.is-scrolled {
  background: rgba(255, 255, 255, 0.86);
}

.brand {
  display: inline-flex;
  align-items: center;
  gap: 10px;
  font-weight: 800;
  color: var(--blue-deep);
  white-space: nowrap;
}

.brand img {
  width: 48px;
  height: 48px;
  border-radius: 14px;
  box-shadow: 0 8px 18px rgba(35, 133, 170, 0.2);
}

.site-nav {
  display: flex;
  align-items: center;
  gap: 8px;
}

.site-nav a {
  padding: 9px 13px;
  border-radius: 999px;
  color: #27556a;
  font-size: 0.95rem;
  font-weight: 700;
  transition: background 0.2s ease, color 0.2s ease, transform 0.2s ease;
}

.site-nav a:hover,
.site-nav a.is-active {
  background: rgba(83, 199, 234, 0.18);
  color: var(--blue-deep);
  transform: translateY(-1px);
}

.site-nav .nav-download {
  color: var(--white);
  background: linear-gradient(135deg, var(--blue), var(--mint-strong));
  box-shadow: 0 10px 24px rgba(38, 145, 176, 0.18);
}

.site-nav .nav-download:hover {
  color: var(--white);
  background: linear-gradient(135deg, #42bbe2, #47ca93);
}

.nav-toggle {
  display: none;
  width: 44px;
  height: 44px;
  border: 0;
  border-radius: 14px;
  background: rgba(83, 199, 234, 0.16);
  cursor: pointer;
}

.nav-toggle span {
  display: block;
  width: 20px;
  height: 2px;
  margin: 5px auto;
  background: var(--blue-deep);
  border-radius: 4px;
  transition: transform 0.22s ease, opacity 0.22s ease;
  transform-origin: center;
}

.nav-toggle.is-open span:nth-child(1) {
  transform: translateY(7px) rotate(45deg);
}

.nav-toggle.is-open span:nth-child(2) {
  opacity: 0;
}

.nav-toggle.is-open span:nth-child(3) {
  transform: translateY(-7px) rotate(-45deg);
}

.hero {
  position: relative;
  min-height: 100vh;
  width: 100vw;
  display: grid;
  align-items: center;
  overflow: hidden;
  isolation: isolate;
}

.hero-bg,
.hero-bg img {
  position: absolute;
  inset: 0;
  width: 100%;
  height: 100%;
}

.hero-bg img {
  object-fit: cover;
  object-position: center;
  transform: scale(1.02);
}

.hero-overlay {
  position: absolute;
  inset: 0;
  z-index: 1;
  background:
    linear-gradient(90deg, rgba(238, 252, 255, 0.92) 0%, rgba(255, 253, 245, 0.74) 42%, rgba(255, 255, 255, 0.18) 100%),
    linear-gradient(180deg, rgba(255, 255, 255, 0.1), rgba(255, 253, 245, 0.62));
}

.sun-glint {
  position: absolute;
  inset: 0;
  z-index: 2;
  pointer-events: none;
  background:
    linear-gradient(112deg, transparent 0%, rgba(255, 255, 255, 0.34) 44%, transparent 48%),
    radial-gradient(circle at 82% 16%, rgba(255, 243, 169, 0.72), transparent 13rem);
  animation: shimmer 10s ease-in-out infinite alternate;
}

@keyframes shimmer {
  from {
    opacity: 0.55;
    transform: translateX(-18px);
  }
  to {
    opacity: 0.95;
    transform: translateX(16px);
  }
}

.hero-content {
  position: relative;
  z-index: 3;
  width: min(100% - 40px, var(--max));
  margin: 0 auto;
  padding: 120px 0 78px;
}

.eyebrow,
.section-kicker {
  margin: 0 0 12px;
  color: var(--blue-deep);
  font-size: 0.82rem;
  font-weight: 900;
  letter-spacing: 0;
  text-transform: uppercase;
}

h1,
h2,
h3,
p {
  overflow-wrap: anywhere;
}

h1 {
  margin: 0;
  max-width: 680px;
  color: #12698f;
  font-size: clamp(2rem, 4.8vw, 3.8rem);
  line-height: 0.96;
  letter-spacing: 0;
  text-shadow: 0 10px 32px rgba(255, 255, 255, 0.74);
}

.hero-main {
  display: grid;
  grid-template-columns: minmax(0, 0.92fr) minmax(280px, 0.62fr);
  gap: clamp(26px, 5vw, 72px);
  align-items: center;
  max-width: 1120px;
}

.hero-copy {
  min-width: 0;
}

.hero-visual {
  margin: 0;
  overflow: hidden;
  border: 5px solid rgba(255, 255, 255, 0.72);
  border-radius: var(--radius-lg);
  background: rgba(255, 255, 255, 0.55);
  box-shadow: 0 24px 64px rgba(27, 119, 154, 0.22);
  transform: rotate(1.2deg);
}

.hero-visual img {
  width: 100%;
  aspect-ratio: 460 / 215;
  object-fit: cover;
  transition: transform 0.4s ease;
}

.hero-visual:hover img {
  transform: scale(1.04);
}

.hero-subtitle {
  max-width: 680px;
  margin: 22px 0 0;
  color: #244e62;
  font-size: clamp(1.12rem, 2vw, 1.42rem);
  font-weight: 700;
}

.hero-actions {
  display: flex;
  flex-wrap: wrap;
  gap: 14px;
  margin: 34px 0 0;
}

.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  min-height: 48px;
  padding: 12px 22px;
  border-radius: 999px;
  font-weight: 900;
  box-shadow: var(--soft-shadow);
  transition: transform 0.2s ease, box-shadow 0.2s ease, background 0.2s ease;
}

.btn:hover {
  transform: translateY(-2px) scale(1.02);
  box-shadow: 0 18px 40px rgba(30, 126, 160, 0.18);
}

.btn-primary {
  color: var(--white);
  background: linear-gradient(135deg, var(--blue), var(--mint-strong));
}

.btn-secondary {
  color: #175d76;
  background: rgba(255, 255, 255, 0.76);
  border: 1px solid rgba(255, 255, 255, 0.76);
  backdrop-filter: blur(10px);
}

.hero-facts {
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: 14px;
  max-width: 860px;
  margin: 46px 0 0;
}

.hero-facts div,
.glass-panel,
.character-card,
.route-card,
.download-panel,
.requirements-grid article,
.system-grid article,
.faq-list details {
  border: 1px solid rgba(255, 255, 255, 0.72);
  background: var(--glass);
  box-shadow: var(--shadow);
  backdrop-filter: blur(12px);
}

.hero-facts div {
  padding: 16px;
  border-radius: var(--radius-md);
}

.hero-facts dt {
  color: var(--blue-deep);
  font-weight: 900;
}

.hero-facts dd {
  margin: 5px 0 0;
  color: #325a6d;
  font-weight: 700;
}

.scroll-cue {
  position: absolute;
  left: 50%;
  bottom: 22px;
  z-index: 4;
  transform: translateX(-50%);
  color: #2b718d;
  font-size: 0.86rem;
  font-weight: 800;
  animation: floatCue 1.8s ease-in-out infinite;
}

@keyframes floatCue {
  50% {
    transform: translate(-50%, 8px);
  }
}

.section {
  position: relative;
  padding: clamp(72px, 9vw, 124px) 20px;
}

.section-soft {
  background: linear-gradient(180deg, rgba(238, 252, 255, 0.72), rgba(255, 253, 245, 0.88));
}

.section-mint {
  background: linear-gradient(135deg, rgba(191, 244, 215, 0.62), rgba(238, 252, 255, 0.78));
}

.section-head,
.intro-layout,
.masonry-gallery,
.character-grid,
.walkthrough-layout,
.split-section,
.download-panel,
.requirements-wrap,
.faq-list,
.timeline,
.site-footer {
  width: min(100%, var(--max));
  margin-inline: auto;
}

.section-head {
  max-width: 780px;
  margin-bottom: 42px;
  text-align: center;
}

.section-head.compact {
  max-width: 720px;
}

.section h2 {
  margin: 0;
  color: #155f7f;
  font-size: clamp(1.65rem, 3vw, 2.55rem);
  line-height: 1.18;
  letter-spacing: 0;
}

.section h3 {
  margin: 0 0 12px;
  color: #1b6078;
  font-size: clamp(1.18rem, 2vw, 1.55rem);
  line-height: 1.35;
}

.section-head p:not(.section-kicker),
.intro-copy p,
.route-card p,
.split-section p,
.download-panel p,
.faq-list p,
.requirements-wrap p {
  color: var(--muted);
}

.intro-layout,
.split-section {
  display: grid;
  grid-template-columns: minmax(0, 1fr) minmax(320px, 0.82fr);
  gap: clamp(24px, 5vw, 58px);
  align-items: center;
}

.glass-panel {
  border-radius: var(--radius-lg);
  padding: clamp(24px, 4vw, 42px);
}

.feature-list,
.download-points,
.route-card ul {
  margin: 18px 0 0;
  padding-left: 1.2rem;
  color: #385d6f;
}

.tilt-card,
.poster-card,
.gallery-item {
  position: relative;
  margin: 0;
  overflow: hidden;
  border-radius: var(--radius-lg);
  box-shadow: var(--shadow);
  background: var(--white);
}

.tilt-card {
  transform: rotate(1.4deg);
}

.tilt-card img,
.poster-card img,
.gallery-item img {
  width: 100%;
  height: 100%;
  object-fit: cover;
  transition: transform 0.42s ease, filter 0.42s ease;
}

.tilt-card:hover img,
.poster-card:hover img,
.gallery-item:hover img {
  transform: scale(1.05);
  filter: saturate(1.07);
}

figcaption {
  position: absolute;
  left: 14px;
  right: 14px;
  bottom: 14px;
  padding: 10px 13px;
  border-radius: 14px;
  color: #23495a;
  background: rgba(255, 255, 255, 0.78);
  font-size: 0.88rem;
  font-weight: 800;
  backdrop-filter: blur(10px);
}

.masonry-gallery {
  display: grid;
  grid-template-columns: repeat(4, minmax(0, 1fr));
  grid-auto-rows: 170px;
  gap: 18px;
}

.gallery-item.wide {
  grid-column: span 2;
}

.gallery-item.tall {
  grid-row: span 2;
}

.character-grid {
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: 22px;
}

.character-card {
  min-height: 300px;
  padding: 28px;
  border-radius: var(--radius-lg);
  background:
    linear-gradient(180deg, rgba(255, 255, 255, 0.8), rgba(238, 252, 255, 0.72)),
    linear-gradient(135deg, rgba(83, 199, 234, 0.18), transparent);
  transition: transform 0.24s ease, box-shadow 0.24s ease;
}

.character-card:hover {
  transform: translateY(-6px);
}

.character-card.accent-yellow {
  background:
    linear-gradient(180deg, rgba(255, 255, 255, 0.82), rgba(255, 250, 212, 0.78)),
    linear-gradient(135deg, rgba(255, 233, 138, 0.34), transparent);
}

.character-card.accent-pink {
  background:
    linear-gradient(180deg, rgba(255, 255, 255, 0.82), rgba(255, 231, 238, 0.78)),
    linear-gradient(135deg, rgba(255, 183, 201, 0.28), transparent);
}

.character-chip {
  display: inline-flex;
  margin-bottom: 22px;
  padding: 7px 12px;
  border-radius: 999px;
  background: rgba(83, 199, 234, 0.16);
  color: var(--blue-deep);
  font-size: 0.82rem;
  font-weight: 900;
}

.character-card p {
  color: var(--muted);
}

.character-card span {
  display: block;
  margin-top: 20px;
  color: #23617b;
  font-weight: 900;
}

.walkthrough-layout {
  display: grid;
  grid-template-columns: 230px minmax(0, 1fr);
  gap: 24px;
  align-items: start;
}

.route-menu {
  position: sticky;
  top: 110px;
  display: grid;
  gap: 10px;
  padding: 12px;
  border-radius: var(--radius-lg);
  background: rgba(255, 255, 255, 0.68);
  box-shadow: var(--soft-shadow);
  backdrop-filter: blur(10px);
}

.route-menu a {
  padding: 11px 13px;
  border-radius: 14px;
  color: #245c73;
  font-weight: 800;
}

.route-menu a:hover,
.route-menu a.is-active {
  background: rgba(83, 199, 234, 0.16);
  color: var(--blue-deep);
}

.route-content {
  display: grid;
  gap: 18px;
}

.route-card {
  padding: clamp(22px, 3vw, 34px);
  border-radius: var(--radius-lg);
}

.route-card ol {
  margin: 0;
  padding-left: 1.25rem;
  color: #385d6f;
}

.route-card li + li {
  margin-top: 7px;
}

.achievements {
  background:
    linear-gradient(135deg, rgba(255, 233, 138, 0.32), rgba(255, 255, 255, 0.76)),
    var(--glass);
}

.system-grid {
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: 16px;
  margin-top: 28px;
}

.system-grid article {
  padding: 20px;
  border-radius: var(--radius-md);
}

.poster-card {
  min-height: 360px;
}

.section-download {
  padding-block: clamp(58px, 7vw, 92px);
  background:
    linear-gradient(135deg, rgba(83, 199, 234, 0.86), rgba(191, 244, 215, 0.84)),
    url("img/tu4.jpg") center/cover fixed;
}

.download-panel {
  display: grid;
  grid-template-columns: minmax(0, 1fr) auto;
  gap: 24px;
  align-items: center;
  padding: clamp(26px, 5vw, 46px);
  border-radius: var(--radius-lg);
}

.download-panel h2,
.download-panel p,
.download-panel li,
.download-panel .section-kicker {
  color: #17465a;
}

.btn-download {
  min-width: 190px;
  color: #17465a;
  background: linear-gradient(135deg, var(--yellow), #fff7c7);
}

.timeline {
  position: relative;
  display: grid;
  gap: 18px;
  max-width: 880px;
  padding: 0;
  list-style: none;
}

.timeline li {
  display: grid;
  grid-template-columns: 180px minmax(0, 1fr);
  gap: 18px;
  padding: 18px 20px;
  border-radius: var(--radius-md);
  background: rgba(255, 255, 255, 0.72);
  box-shadow: var(--soft-shadow);
}

.timeline time {
  color: var(--blue-deep);
  font-weight: 900;
}

.requirements-wrap {
  display: grid;
  grid-template-columns: 0.75fr 1fr;
  gap: 24px;
  align-items: start;
}

.requirements-grid {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 18px;
}

.requirements-grid article {
  padding: 24px;
  border-radius: var(--radius-lg);
}

.faq-list {
  display: grid;
  gap: 14px;
  max-width: 900px;
}

.faq-list details {
  border-radius: var(--radius-md);
  padding: 0 20px;
}

.faq-list summary {
  cursor: pointer;
  padding: 20px 0;
  color: #1d617b;
  font-weight: 900;
}

.faq-list summary::marker {
  color: var(--blue);
}

.faq-list p {
  margin: 0;
  padding: 0 0 20px;
}

.site-footer {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 24px;
  padding: 34px 20px 46px;
  color: #31596a;
}

.site-footer p {
  max-width: 680px;
  margin: 8px 0 0;
}

.back-top {
  flex: 0 0 auto;
  padding: 10px 14px;
  border-radius: 999px;
  color: var(--blue-deep);
  background: rgba(83, 199, 234, 0.14);
  font-weight: 900;
}

.lightbox {
  position: fixed;
  inset: 0;
  z-index: 100;
  display: grid;
  place-items: center;
  padding: 24px;
  background: rgba(18, 48, 64, 0.78);
  backdrop-filter: blur(10px);
}

.lightbox[hidden] {
  display: none;
}

.lightbox img {
  max-width: min(96vw, 1280px);
  max-height: 86vh;
  border-radius: var(--radius-lg);
  box-shadow: 0 28px 80px rgba(0, 0, 0, 0.32);
}

.lightbox-close {
  position: absolute;
  top: 20px;
  right: 20px;
  width: 44px;
  height: 44px;
  border: 0;
  border-radius: 50%;
  color: var(--ink);
  background: rgba(255, 255, 255, 0.9);
  font-size: 2rem;
  line-height: 1;
  cursor: pointer;
}

@media (prefers-reduced-motion: reduce) {
  *,
  *::before,
  *::after {
    scroll-behavior: auto !important;
    animation-duration: 0.01ms !important;
    animation-iteration-count: 1 !important;
    transition-duration: 0.01ms !important;
  }
}

@media (max-width: 980px) {
  .site-header {
    inset: 12px 14px auto;
  }

  .nav-toggle {
    display: block;
  }

  .site-nav {
    position: fixed;
    left: 14px;
    right: 14px;
    top: 82px;
    display: none;
    grid-template-columns: 1fr;
    padding: 14px;
    border-radius: var(--radius-lg);
    background: rgba(255, 255, 255, 0.93);
    box-shadow: var(--shadow);
  }

  .site-nav.is-open {
    display: grid;
  }

  .site-nav a {
    padding: 13px 14px;
  }

  .site-nav .nav-download {
    text-align: center;
  }

  .hero-overlay {
    background:
      linear-gradient(180deg, rgba(238, 252, 255, 0.92) 0%, rgba(255, 253, 245, 0.82) 46%, rgba(255, 255, 255, 0.28) 100%);
  }

  .hero-content {
    width: min(100% - 28px, var(--max));
  }

  .hero-facts,
  .hero-main,
  .character-grid,
  .system-grid,
  .requirements-grid,
  .requirements-wrap,
  .intro-layout,
  .split-section,
  .download-panel {
    grid-template-columns: 1fr;
  }

  .walkthrough-layout {
    grid-template-columns: 1fr;
  }

  .route-menu {
    position: static;
    display: flex;
    overflow-x: auto;
  }

  .route-menu a {
    flex: 0 0 auto;
  }

  .masonry-gallery {
    grid-template-columns: repeat(2, minmax(0, 1fr));
    grid-auto-rows: 180px;
  }

  .download-panel .btn {
    width: 100%;
  }
}

@media (max-width: 640px) {
  .brand span {
    max-width: 6em;
    overflow: hidden;
    white-space: nowrap;
  }

  .hero {
    min-height: 100svh;
  }

  .hero-bg img {
    object-position: 58% center;
  }

  .hero-content {
    padding-top: 116px;
    padding-bottom: 70px;
  }

  h1 {
    font-size: clamp(1.85rem, 9vw, 2.8rem);
  }

  .hero-main {
    gap: 22px;
  }

  .hero-visual {
    max-width: 360px;
    border-width: 3px;
  }

  .hero-subtitle {
    font-size: 1.05rem;
  }

  .hero-actions {
    display: grid;
  }

  .btn {
    width: 100%;
  }

  .section {
    padding-inline: 14px;
  }

  .masonry-gallery {
    grid-template-columns: 1fr;
    grid-auto-rows: 240px;
  }

  .gallery-item.wide,
  .gallery-item.tall {
    grid-column: auto;
    grid-row: auto;
  }

  .timeline li {
    grid-template-columns: 1fr;
    gap: 6px;
  }

  .site-footer {
    flex-direction: column;
    align-items: flex-start;
  }
}