:root {
  --bg: #111713;
  --panel: #19221b;
  --ink: #edf0df;
  --muted: #a5b09f;
  --acid: #d7f174;
  --line: #354030;
}
* {
  box-sizing: border-box;
}
html {
  scroll-behavior: smooth;
  scroll-padding-top: 84px;
}
body {
  margin: 0;
  background: var(--bg);
  color: var(--ink);
  font-family: Arial, "Microsoft YaHei", "PingFang SC", sans-serif;
  line-height: 1.65;
}
a {
  color: inherit;
  text-decoration: none;
}
a:focus-visible,
video:focus-visible {
  outline: 3px solid var(--acid);
  outline-offset: 5px;
}
.nav {
  height: 84px;
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 0 5vw;
  border-bottom: 1px solid #ffffff20;
  position: absolute;
  z-index: 2;
  width: 100%;
  background: #11171370;
}
.brand {
  font-size: 23px;
  font-weight: 800;
  letter-spacing: 0.08em;
  display: flex;
  align-items: center;
  gap: 13px;
}
.brand small {
  font-size: 12px;
  letter-spacing: 0.18em;
  color: var(--muted);
}
.symbol {
  border: 1px solid var(--acid);
  color: var(--acid);
  font-size: 20px;
  padding: 0 7px;
  transform: skew(-8deg);
}
nav {
  display: flex;
  gap: 34px;
  align-items: center;
  font-size: 13px;
}
.nav-download {
  border-left: 1px solid #ffffff35;
  padding-left: 30px;
  color: var(--acid);
}
.nav-download span {
  margin-left: 20px;
}
.hero {
  min-height: 800px;
  height: 100svh;
  max-height: 1100px;
  position: relative;
  overflow: hidden;
  padding: 170px 7vw 100px;
  display: flex;
  align-items: center;
}
.hero-image {
  position: absolute;
  inset: 0;
  background: url("assets/lujiazui.png") 80% 50% / cover;
  filter: saturate(0.65);
  opacity: 0.8;
}
.hero:after {
  content: "";
  position: absolute;
  inset: 0;
  background:
    linear-gradient(90deg, #111713 4%, #111713b8 40%, #11171310 100%),
    linear-gradient(0deg, #111713, transparent 50%);
}
.hero-grid {
  position: absolute;
  inset: 0;
  background: repeating-linear-gradient(
    90deg,
    transparent 0,
    transparent calc(25% - 1px),
    #ffffff0a 25%
  );
  z-index: 1;
}
.hero-copy {
  position: relative;
  z-index: 1;
}
.eyebrow {
  font-size: 11px;
  letter-spacing: 0.18em;
  color: var(--acid);
  font-weight: 600;
  margin: 0 0 25px;
}
.dot {
  display: inline-block;
  width: 6px;
  height: 6px;
  background: var(--acid);
  border-radius: 50%;
  margin-right: 10px;
  vertical-align: middle;
}
h1 {
  font-size: clamp(42px, 5.8vw, 84px);
  line-height: 1.2;
  letter-spacing: -0.04em;
  margin: 0 0 30px;
  font-weight: 850;
}
h1 span {
  color: var(--acid);
}
.intro {
  font-size: 17px;
  color: #c9d0bc;
  line-height: 1.9;
}
.actions {
  display: flex;
  gap: 30px;
  align-items: center;
  margin-top: 38px;
}
.button {
  display: inline-flex;
  align-items: center;
  justify-content: space-between;
  gap: 40px;
  padding: 18px 24px;
  font-size: 15px;
  font-weight: 700;
  transition:
    background 0.2s,
    transform 0.2s;
}
.primary {
  background: var(--acid);
  color: #19200e;
}
.primary:hover {
  background: #e9ffa1;
  transform: translateY(-2px);
}
.film-link {
  font-size: 13px;
}
.play {
  display: inline-flex;
  width: 32px;
  height: 32px;
  border: 1px solid #ffffff60;
  border-radius: 50%;
  align-items: center;
  justify-content: center;
  font-size: 10px;
  margin-right: 8px;
}
.hero-note {
  font-size: 11px;
  letter-spacing: 0.08em;
  color: var(--muted);
  margin-top: 18px;
}
.hero-foot {
  position: absolute;
  bottom: 30px;
  left: 7vw;
  right: 7vw;
  display: flex;
  justify-content: space-between;
  border-top: 1px solid #ffffff24;
  padding-top: 20px;
  font-size: 10px;
  color: var(--muted);
  letter-spacing: 0.12em;
  z-index: 1;
}
.section {
  padding: 100px 7vw;
  max-width: 1600px;
  margin: 0 auto;
}
.section-heading h2 {
  font-size: clamp(29px, 3.2vw, 46px);
  line-height: 1.35;
  margin: 0 0 20px;
  letter-spacing: -0.03em;
}
.section-heading p:not(.eyebrow) {
  color: var(--muted);
  font-size: 14px;
}
.video-frame {
  margin-top: 45px;
  border: 1px solid var(--line);
  background: #080c09;
}
.video-frame video {
  display: block;
  width: 100%;
  max-height: 650px;
  aspect-ratio: 16/9;
}
.video-caption {
  display: flex;
  justify-content: space-between;
  padding: 16px 20px;
  font-size: 11px;
  color: var(--muted);
  border-top: 1px solid var(--line);
}
.world {
  border-top: 1px solid var(--line);
}
.maps {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 24px;
  margin-top: 45px;
}
.map-card {
  background: var(--panel);
  border: 1px solid var(--line);
  overflow: hidden;
}
.map-card > img {
  display: block;
  width: 100%;
  height: 310px;
  object-fit: cover;
}
.map-card > div:not(.training-art) {
  padding: 30px;
}
.tag {
  font-size: 10px;
  letter-spacing: 0.15em;
  color: var(--acid);
}
h3 {
  font-size: 26px;
  margin: 12px 0;
}
.map-card p {
  font-size: 14px;
  color: var(--muted);
  max-width: 440px;
}
.map-fact {
  display: block;
  border-top: 1px solid var(--line);
  padding-top: 20px;
  margin-top: 24px;
  font-size: 11px;
  color: #b6c1a7;
}
.precision {
  font-size: 11px;
  color: var(--muted);
  margin-top: 18px;
}
.training-art {
  height: 310px;
  background: radial-gradient(ellipse at center, #66745b, #273228 70%);
  position: relative;
  overflow: hidden;
}
.training-art:before {
  content: "";
  position: absolute;
  inset: 50% -50% -100%;
  background:
    repeating-linear-gradient(90deg, transparent 0 59px, #ffffff12 60px),
    repeating-linear-gradient(0deg, transparent 0 59px, #ffffff12 60px);
  transform: perspective(200px) rotateX(45deg);
}
.slab {
  position: absolute;
  width: 240px;
  height: 32px;
  left: calc(50% - 120px);
  top: 95px;
  background: #bbbbaa;
  box-shadow: 14px -12px #8b9480;
}
.pillar {
  position: absolute;
  width: 26px;
  height: 113px;
  background: #aaa998;
  top: 127px;
  box-shadow: 10px -6px #737e68;
}
.p1 {
  left: calc(50% - 100px);
}
.p2 {
  left: calc(50% + 70px);
}
.crosshair {
  position: absolute;
  left: 49%;
  top: 40%;
  color: var(--acid);
  font-size: 32px;
  font-weight: 200;
}
.training-art > span {
  position: absolute;
  bottom: 15px;
  left: 20px;
  font: 10px monospace;
  color: var(--muted);
}
.principles {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 50px;
  border-top: 1px solid var(--line);
  border-bottom: 1px solid var(--line);
}
.index {
  font: 12px monospace;
  color: var(--acid);
}
.principles h3 {
  font-size: 22px;
}
.principles p {
  font-size: 14px;
  color: var(--muted);
}
.specs {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 70px;
}
.spec-table > div {
  display: flex;
  justify-content: space-between;
  gap: 20px;
  border-bottom: 1px solid var(--line);
  padding: 18px 0;
  font-size: 13px;
}
.spec-table span {
  color: var(--muted);
}
.spec-table strong {
  font-weight: 400;
  text-align: right;
}
.spec-table p {
  color: var(--muted);
  font-size: 11px;
  margin-top: 24px;
}
.download {
  text-align: center;
  background: radial-gradient(ellipse at bottom, #35442a, var(--bg) 75%);
  border-top: 1px solid var(--line);
  padding-bottom: 110px;
}
.download h2 {
  font-size: clamp(40px, 5vw, 70px);
  line-height: 1.2;
  margin: 24px 0 40px;
}
.download > p:not(.eyebrow) {
  font-size: 12px;
  color: var(--muted);
}
.download-steps {
  display: flex;
  justify-content: center;
  gap: 40px;
  font-size: 12px;
  color: #c9d0bc;
  margin: 35px 0 25px;
}
.checksum {
  font-size: 11px;
  color: var(--muted);
  text-decoration: underline;
}
footer {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 25px;
  padding: 35px 5vw;
  border-top: 1px solid var(--line);
  font-size: 10px;
  color: var(--muted);
}
footer > .brand {
  color: var(--ink);
}
@media (max-width: 760px) {
  .nav {
    height: 72px;
    padding: 0 6vw;
  }
  .nav nav {
    gap: 16px;
  }
  .nav nav > a:not(.nav-download) {
    display: none;
  }
  .nav-download {
    padding-left: 0;
    border: 0;
  }
  .hero {
    padding: 140px 6vw 100px;
    min-height: 730px;
    height: 95svh;
  }
  .hero-image {
    background-position: 62% center;
    opacity: 0.5;
  }
  .hero:after {
    background:
      linear-gradient(90deg, #111713d9, #11171345),
      linear-gradient(0deg, #111713, transparent);
  }
  .hero .eyebrow {
    font-size: 9px;
  }
  .hero h1 {
    font-size: 46px;
  }
  .intro {
    font-size: 14px;
  }
  .actions {
    align-items: flex-start;
    flex-direction: column;
    gap: 20px;
  }
  .hero-foot {
    left: 6vw;
    right: 6vw;
  }
  .hero-foot span:last-child {
    display: none;
  }
  .section {
    padding: 65px 6vw;
  }
  .maps,
  .principles,
  .specs {
    grid-template-columns: 1fr;
    gap: 26px;
  }
  .map-card > img,
  .training-art {
    height: 240px;
  }
  .principles {
    gap: 30px;
  }
  .principles > div + div {
    border-top: 1px solid var(--line);
    padding-top: 25px;
  }
  .download-steps {
    gap: 12px;
    flex-wrap: wrap;
    font-size: 11px;
  }
  footer {
    align-items: flex-start;
    flex-direction: column;
  }
  .video-caption {
    font-size: 10px;
  }
}
@media (prefers-reduced-motion: reduce) {
  html {
    scroll-behavior: auto;
  }
  .button {
    transition: none;
  }
}