:root {
  --ink: #14283a;
  --ink-soft: #3d556b;
  --paper: #f3f8fb;
  --sea: #0f7c7a;
  --sea-deep: #0a5c5a;
  --sun: #e8b84a;
  --white: #ffffff;
  --line: rgba(20, 40, 58, 0.1);

  --font-display: "Noto Serif SC", "Songti SC", serif;
  --font-body: "Noto Sans SC", "PingFang SC", "Helvetica Neue", sans-serif;

  --max: 40rem;
}

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

html {
  scroll-behavior: smooth;
}

body {
  margin: 0;
  min-height: 100vh;
  color: var(--ink);
  font-family: var(--font-body);
  font-weight: 400;
  line-height: 1.65;
  background: var(--paper);
  -webkit-font-smoothing: antialiased;
}

.atmosphere {
  position: fixed;
  inset: 0;
  z-index: -1;
  overflow: hidden;
  background:
    radial-gradient(120% 80% at 10% 0%, #eaf5fa 0%, transparent 55%),
    radial-gradient(90% 70% at 90% 10%, #dff0ec 0%, transparent 50%),
    linear-gradient(180deg, #eef6fa 0%, var(--paper) 45%, #e8f2f0 100%);
}

.glow {
  position: absolute;
  border-radius: 50%;
  filter: blur(48px);
  opacity: 0.55;
  animation: drift 18s ease-in-out infinite alternate;
}

.glow-a {
  width: min(55vw, 28rem);
  height: min(55vw, 28rem);
  top: -8%;
  left: -6%;
  background: #b9dde8;
}

.glow-b {
  width: min(50vw, 24rem);
  height: min(50vw, 24rem);
  top: 12%;
  right: -8%;
  background: #c5e5d8;
  animation-delay: -6s;
  animation-duration: 22s;
}

.grid-fade {
  position: absolute;
  inset: 0;
  background-image:
    linear-gradient(var(--line) 1px, transparent 1px),
    linear-gradient(90deg, var(--line) 1px, transparent 1px);
  background-size: 48px 48px;
  mask-image: linear-gradient(180deg, rgba(0, 0, 0, 0.35), transparent 70%);
  opacity: 0.45;
}

.page {
  width: min(100% - 2.5rem, 52rem);
  margin: 0 auto;
  padding: clamp(3.5rem, 12vh, 7rem) 0 clamp(3rem, 8vh, 5rem);
}

.hero {
  max-width: var(--max);
  min-height: min(72vh, 36rem);
  display: flex;
  flex-direction: column;
  justify-content: center;
}

.brand {
  margin: 0 0 1.75rem;
  font-family: var(--font-display);
  font-size: clamp(2.6rem, 8vw, 4rem);
  font-weight: 700;
  line-height: 1.15;
  letter-spacing: 0.08em;
  color: var(--ink);
  position: relative;
  width: fit-content;
  opacity: 0;
  animation: rise 0.8s ease both;
}

.brand::after {
  content: "";
  position: absolute;
  left: 0;
  bottom: 0.12em;
  width: 100%;
  height: 0.18em;
  background: linear-gradient(90deg, var(--sun), rgba(232, 184, 74, 0.2));
  border-radius: 2px;
  transform: scaleX(0);
  transform-origin: left;
  animation: underline 0.7s 0.55s ease both;
  z-index: -1;
}

.headline {
  margin: 0 0 1.25rem;
  font-family: var(--font-display);
  font-size: clamp(1.65rem, 4.5vw, 2.35rem);
  font-weight: 600;
  line-height: 1.35;
  letter-spacing: 0.02em;
  opacity: 0;
  animation: rise 0.8s 0.12s ease both;
}

.headline em {
  font-style: normal;
  color: var(--sea-deep);
}

.lede {
  margin: 0 0 2rem;
  max-width: 28rem;
  font-size: clamp(1rem, 2.2vw, 1.125rem);
  color: var(--ink-soft);
  opacity: 0;
  animation: rise 0.8s 0.22s ease both;
}

.cta-group {
  opacity: 0;
  animation: rise 0.8s 0.32s ease both;
}

.cta {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  min-height: 2.85rem;
  padding: 0.7rem 1.4rem;
  border-radius: 0.5rem;
  background: var(--sea);
  color: var(--white);
  font-size: 0.95rem;
  font-weight: 500;
  letter-spacing: 0.04em;
  text-decoration: none;
  transition: background 0.2s ease, transform 0.2s ease;
}

.cta:hover {
  background: var(--sea-deep);
  transform: translateY(-1px);
}

.cta:focus-visible {
  outline: 2px solid var(--sea);
  outline-offset: 3px;
}

.about {
  margin-top: clamp(3.5rem, 10vh, 6rem);
  padding-top: clamp(2.5rem, 6vh, 3.5rem);
  border-top: 1px solid var(--line);
  max-width: var(--max);
  opacity: 0;
  transform: translateY(12px);
  transition: opacity 0.7s ease, transform 0.7s ease;
}

.about.is-visible {
  opacity: 1;
  transform: none;
}

.about-title {
  margin: 0 0 0.85rem;
  font-family: var(--font-display);
  font-size: clamp(1.35rem, 3vw, 1.6rem);
  font-weight: 700;
  letter-spacing: 0.04em;
}

.about-text {
  margin: 0 0 2rem;
  color: var(--ink-soft);
  font-size: 1rem;
}

.points {
  list-style: none;
  margin: 0;
  padding: 0;
  display: grid;
  gap: 1.1rem;
}

.points li {
  display: grid;
  gap: 0.2rem;
  padding-left: 1rem;
  border-left: 3px solid var(--sun);
}

.point-label {
  font-weight: 600;
  font-size: 1rem;
  letter-spacing: 0.02em;
}

.point-desc {
  color: var(--ink-soft);
  font-size: 0.92rem;
}

.site-footer {
  width: min(100% - 2.5rem, 52rem);
  margin: 0 auto;
  padding: 1.75rem 0 2.5rem;
  border-top: 1px solid var(--line);
}

.footer-meta {
  display: flex;
  flex-direction: column;
  gap: 0.35rem;
  color: var(--ink-soft);
  font-size: 0.75rem;
  line-height: 1.6;
}

.copyright,
.beian {
  margin: 0;
}

.beian a {
  color: inherit;
  text-decoration: none;
  border-bottom: 1px solid transparent;
  transition: color 0.2s ease, border-color 0.2s ease;
}

.beian a:hover {
  color: var(--sea);
  border-bottom-color: currentColor;
}

.beian a:focus-visible {
  outline: 2px solid var(--sea);
  outline-offset: 3px;
}

@keyframes rise {
  from {
    opacity: 0;
    transform: translateY(14px);
  }
  to {
    opacity: 1;
    transform: none;
  }
}

@keyframes underline {
  from {
    transform: scaleX(0);
  }
  to {
    transform: scaleX(1);
  }
}

@keyframes drift {
  from {
    transform: translate3d(0, 0, 0);
  }
  to {
    transform: translate3d(2%, 4%, 0);
  }
}

@media (max-width: 540px) {
  .points {
    gap: 1.25rem;
  }
}

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

  .brand,
  .headline,
  .lede,
  .cta-group,
  .about {
    animation: none;
    opacity: 1;
    transform: none;
    transition: none;
  }

  .brand::after {
    animation: none;
    transform: none;
  }

  .glow {
    animation: none;
  }

  .cta:hover {
    transform: none;
  }
}