:root {
  --ink: #1c2421;
  --ink-soft: #3a4742;
  --mist: #e8eef0;
  --mist-deep: #d3dde0;
  --paper: #f4f7f6;
  --celadon: #4f7d68;
  --celadon-deep: #3a5f4e;
  --sand: #c4a574;
  --line: rgba(28, 36, 33, 0.12);
  --glow: rgba(79, 125, 104, 0.18);
  /* 优先系统中文字体，避免备案服务器访问不到 Google Fonts */
  --font-display: "Songti SC", "STSong", "Noto Serif SC", "Source Han Serif SC", Georgia, serif;
  --font-body: "PingFang SC", "Hiragino Sans GB", "Microsoft YaHei", "Noto Sans SC", sans-serif;
  --radius: 2px;
  --space: clamp(1.25rem, 3vw, 2.5rem);
  --max: 72rem;
}

*,
*::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: 1.7;
  background:
    radial-gradient(1200px 600px at 10% -10%, rgba(79, 125, 104, 0.16), transparent 55%),
    radial-gradient(900px 500px at 100% 0%, rgba(196, 165, 116, 0.14), transparent 50%),
    linear-gradient(165deg, #eef3f4 0%, var(--paper) 42%, #e6ecea 100%);
  background-attachment: fixed;
}

body::before {
  content: "";
  position: fixed;
  inset: 0;
  pointer-events: none;
  opacity: 0.35;
  background-image:
    linear-gradient(rgba(28, 36, 33, 0.03) 1px, transparent 1px),
    linear-gradient(90deg, rgba(28, 36, 33, 0.03) 1px, transparent 1px);
  background-size: 48px 48px;
  mask-image: linear-gradient(to bottom, black, transparent 85%);
  z-index: 0;
}

a {
  color: var(--celadon-deep);
  text-decoration-thickness: 1px;
  text-underline-offset: 0.2em;
  transition: color 0.2s ease;
}

a:hover {
  color: var(--ink);
}

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

.site {
  position: relative;
  z-index: 1;
  min-height: 100vh;
  display: flex;
  flex-direction: column;
}

.wrap {
  width: min(100% - 2 * var(--space), var(--max));
  margin-inline: auto;
}

/* ----- Nav ----- */
.nav {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 1rem;
  padding: 1.25rem 0;
}

.nav-brand {
  font-family: var(--font-display);
  font-size: 1.15rem;
  font-weight: 550;
  letter-spacing: 0.02em;
  color: var(--ink);
  text-decoration: none;
}

.nav-links {
  display: flex;
  gap: 1.25rem;
  list-style: none;
  margin: 0;
  padding: 0;
}

.nav-links a {
  color: var(--ink-soft);
  text-decoration: none;
  font-size: 0.95rem;
}

.nav-links a[aria-current="page"],
.nav-links a:hover {
  color: var(--ink);
}

/* ----- Hero ----- */
.hero {
  flex: 1;
  display: grid;
  align-items: end;
  min-height: min(88vh, 56rem);
  padding: 2rem 0 4rem;
  position: relative;
  overflow: hidden;
}

.hero-plane {
  position: absolute;
  inset: 0 -8%;
  background:
    linear-gradient(120deg, transparent 35%, rgba(79, 125, 104, 0.08) 55%, transparent 75%),
    radial-gradient(ellipse 70% 55% at 70% 60%, rgba(196, 165, 116, 0.22), transparent 70%),
    radial-gradient(ellipse 50% 40% at 20% 80%, rgba(79, 125, 104, 0.2), transparent 65%);
  transform: translateY(12px) scale(1.02);
  opacity: 0;
  animation: rise-plane 1.1s cubic-bezier(0.22, 1, 0.36, 1) 0.1s forwards;
}

.hero-plane::after {
  content: "";
  position: absolute;
  right: 8%;
  bottom: 12%;
  width: min(42vw, 28rem);
  aspect-ratio: 4 / 5;
  border: 1px solid var(--line);
  background:
    linear-gradient(160deg, rgba(244, 247, 246, 0.2), rgba(79, 125, 104, 0.25)),
    repeating-linear-gradient(
      -18deg,
      transparent,
      transparent 12px,
      rgba(28, 36, 33, 0.04) 12px,
      rgba(28, 36, 33, 0.04) 13px
    );
  opacity: 0;
  animation: fade-frame 1.2s ease 0.35s forwards;
}

.hero-content {
  position: relative;
  z-index: 1;
  max-width: 36rem;
  padding-bottom: 1rem;
}

.brand-mark {
  display: block;
  font-family: var(--font-display);
  font-size: clamp(3rem, 9vw, 5.75rem);
  font-weight: 550;
  line-height: 0.95;
  letter-spacing: -0.02em;
  margin: 0 0 1.25rem;
  opacity: 0;
  transform: translateY(24px);
  animation: rise-text 0.9s cubic-bezier(0.22, 1, 0.36, 1) 0.2s forwards;
}

.hero-lead {
  margin: 0 0 0.75rem;
  font-size: clamp(1.15rem, 2.4vw, 1.45rem);
  font-weight: 500;
  color: var(--ink);
  opacity: 0;
  transform: translateY(18px);
  animation: rise-text 0.85s cubic-bezier(0.22, 1, 0.36, 1) 0.38s forwards;
}

.hero-support {
  margin: 0 0 2rem;
  color: var(--ink-soft);
  max-width: 28rem;
  opacity: 0;
  transform: translateY(18px);
  animation: rise-text 0.85s cubic-bezier(0.22, 1, 0.36, 1) 0.5s forwards;
}

.cta-row {
  display: flex;
  flex-wrap: wrap;
  gap: 0.75rem 1rem;
  opacity: 0;
  transform: translateY(16px);
  animation: rise-text 0.85s cubic-bezier(0.22, 1, 0.36, 1) 0.62s forwards;
}

.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  padding: 0.7rem 1.25rem;
  border: 1px solid var(--ink);
  background: var(--ink);
  color: var(--paper);
  font: inherit;
  font-size: 0.95rem;
  text-decoration: none;
  cursor: pointer;
  transition: background 0.2s ease, color 0.2s ease, border-color 0.2s ease;
}

.btn:hover {
  background: var(--celadon-deep);
  border-color: var(--celadon-deep);
  color: var(--paper);
}

.btn-ghost {
  background: transparent;
  color: var(--ink);
}

.btn-ghost:hover {
  background: rgba(28, 36, 33, 0.06);
  color: var(--ink);
  border-color: var(--ink);
}

/* ----- Page sections ----- */
.page {
  padding: 2.5rem 0 4rem;
}

.page-title {
  font-family: var(--font-display);
  font-size: clamp(2rem, 5vw, 3rem);
  font-weight: 550;
  letter-spacing: -0.02em;
  margin: 0 0 0.75rem;
  opacity: 0;
  transform: translateY(16px);
  animation: rise-text 0.8s cubic-bezier(0.22, 1, 0.36, 1) 0.1s forwards;
}

.page-lead {
  margin: 0 0 2.5rem;
  color: var(--ink-soft);
  max-width: 36rem;
  opacity: 0;
  transform: translateY(14px);
  animation: rise-text 0.8s cubic-bezier(0.22, 1, 0.36, 1) 0.25s forwards;
}

.prose {
  max-width: 40rem;
  opacity: 0;
  transform: translateY(14px);
  animation: rise-text 0.8s cubic-bezier(0.22, 1, 0.36, 1) 0.35s forwards;
}

.prose p {
  margin: 0 0 1.1rem;
}

.prose h2 {
  font-family: var(--font-display);
  font-size: 1.35rem;
  font-weight: 550;
  margin: 2rem 0 0.75rem;
}

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

.meta-list li {
  display: grid;
  grid-template-columns: 5.5rem 1fr;
  gap: 0.75rem;
  padding-bottom: 0.85rem;
  border-bottom: 1px solid var(--line);
}

.meta-list span {
  color: var(--ink-soft);
  font-size: 0.9rem;
}

.contact-email {
  font-family: var(--font-display);
  font-size: clamp(1.4rem, 3.5vw, 2rem);
  text-decoration: none;
  color: var(--ink);
  border-bottom: 1px solid var(--line);
  padding-bottom: 0.15em;
}

.contact-email:hover {
  color: var(--celadon-deep);
  border-color: var(--celadon);
}

.socials {
  display: flex;
  flex-wrap: wrap;
  gap: 1rem;
  margin-top: 2rem;
  padding: 0;
  list-style: none;
}

.socials a {
  text-decoration: none;
  color: var(--ink-soft);
  border-bottom: 1px solid transparent;
}

.socials a:hover {
  color: var(--ink);
  border-color: var(--ink);
}

/* ----- Footer ----- */
.footer {
  margin-top: auto;
  border-top: 1px solid var(--line);
  padding: 1.25rem 0 1.75rem;
  color: var(--ink-soft);
  font-size: 0.85rem;
}

.footer-inner {
  display: flex;
  flex-wrap: wrap;
  gap: 0.5rem 1.5rem;
  align-items: center;
  justify-content: space-between;
}

.footer a {
  color: var(--ink-soft);
  text-decoration: none;
}

.footer a:hover {
  color: var(--ink);
}

.icp-link {
  letter-spacing: 0.02em;
}

/* ----- Reveal utility for reduced motion ----- */
@keyframes rise-text {
  to {
    opacity: 1;
    transform: translateY(0);
  }
}

@keyframes rise-plane {
  to {
    opacity: 1;
    transform: translateY(0) scale(1);
  }
}

@keyframes fade-frame {
  to {
    opacity: 1;
  }
}

@media (prefers-reduced-motion: reduce) {
  *,
  *::before,
  *::after {
    animation: none !important;
    transition: none !important;
  }

  .brand-mark,
  .hero-lead,
  .hero-support,
  .cta-row,
  .hero-plane,
  .hero-plane::after,
  .page-title,
  .page-lead,
  .prose {
    opacity: 1;
    transform: none;
  }
}

@media (max-width: 640px) {
  .nav-links {
    gap: 0.85rem;
  }

  .hero {
    min-height: 78vh;
    align-items: center;
  }

  .hero-plane::after {
    right: -6%;
    bottom: 4%;
    width: 70vw;
    opacity: 0.55;
  }

  .meta-list li {
    grid-template-columns: 1fr;
    gap: 0.2rem;
  }
}