:root {
  --color-bg: #090b10;
  --color-bg-soft: #0d1118;
  --color-surface: #111620;
  --color-surface-hover: #151c27;
  --color-text: #f2f5f9;
  --color-text-muted: #929cab;
  --color-text-soft: #bbc3ce;
  --color-line: rgba(255, 255, 255, 0.1);
  --color-line-strong: rgba(255, 255, 255, 0.16);
  --color-accent: #69b7ff;
  --color-accent-soft: rgba(105, 183, 255, 0.12);
  --font-sans: -apple-system, BlinkMacSystemFont, "PingFang SC", "Hiragino Sans GB", "Microsoft YaHei", "Segoe UI", Helvetica, Arial, sans-serif;
  --font-mono: "SFMono-Regular", Consolas, "Liberation Mono", monospace;
  --container: 1180px;
  --header-height: 76px;
  --radius: 3px;
}

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

html {
  scroll-behavior: smooth;
  scroll-padding-top: var(--header-height);
}

body {
  min-width: 320px;
  margin: 0;
  overflow-x: hidden;
  color: var(--color-text);
  background: var(--color-bg);
  font-family: var(--font-sans);
  font-size: 16px;
  line-height: 1.75;
  text-rendering: optimizeLegibility;
  -webkit-font-smoothing: antialiased;
}

body.nav-open {
  overflow: hidden;
}

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

button,
a {
  -webkit-tap-highlight-color: transparent;
}

button {
  color: inherit;
  font: inherit;
}

.container {
  width: min(calc(100% - 48px), var(--container));
  margin-inline: auto;
}

.skip-link {
  position: fixed;
  z-index: 1000;
  top: 12px;
  left: 12px;
  padding: 10px 14px;
  color: var(--color-bg);
  background: var(--color-text);
  transform: translateY(-150%);
  transition: transform 180ms ease;
}

.skip-link:focus {
  transform: translateY(0);
}

.site-header {
  position: fixed;
  z-index: 100;
  top: 0;
  right: 0;
  left: 0;
  height: var(--header-height);
  border-bottom: 1px solid transparent;
  transition: background-color 180ms ease, border-color 180ms ease;
}

.site-header.is-scrolled {
  border-color: var(--color-line);
  background: rgba(9, 11, 16, 0.88);
  -webkit-backdrop-filter: blur(16px);
  backdrop-filter: blur(16px);
}

.header-inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  height: 100%;
}

.brand {
  display: inline-flex;
  gap: 12px;
  align-items: center;
  font-weight: 650;
  letter-spacing: -0.02em;
}

.brand-name {
  display: flex;
  flex-direction: column;
  line-height: 1.05;
}

.brand-name small {
  margin-top: 5px;
  color: var(--color-text-muted);
  font-family: var(--font-mono);
  font-size: 0.56rem;
  font-weight: 500;
  letter-spacing: 0.08em;
}

.brand-mark {
  position: relative;
  width: 18px;
  height: 18px;
  border: 1px solid var(--color-accent);
}

.brand-mark::after {
  position: absolute;
  inset: 4px;
  border-top: 1px solid var(--color-accent);
  border-left: 1px solid var(--color-accent);
  content: "";
}

.site-nav {
  display: flex;
  gap: 34px;
  align-items: center;
}

.site-nav a {
  position: relative;
  padding: 8px 0;
  color: var(--color-text-muted);
  font-size: 0.82rem;
  font-weight: 600;
  letter-spacing: 0.01em;
  transition: color 160ms ease;
}

.site-nav a::after {
  position: absolute;
  right: 0;
  bottom: 2px;
  left: 0;
  height: 1px;
  background: var(--color-accent);
  content: "";
  transform: scaleX(0);
  transform-origin: right;
  transition: transform 180ms ease;
}

.site-nav a:hover,
.site-nav a:focus-visible,
.site-nav a.is-active {
  color: var(--color-text);
}

.site-nav a.is-active::after,
.site-nav a:hover::after {
  transform: scaleX(1);
  transform-origin: left;
}

.nav-toggle {
  display: none;
  width: 42px;
  height: 42px;
  padding: 0;
  border: 1px solid var(--color-line);
  background: transparent;
  cursor: pointer;
}

.nav-toggle span {
  display: block;
  width: 18px;
  height: 1px;
  margin: 5px auto;
  background: currentColor;
  transition: transform 180ms ease;
}

.section {
  position: relative;
  padding: 132px 0;
}

.section-bordered {
  border-top: 1px solid var(--color-line);
}

.section-muted {
  border-top: 1px solid var(--color-line);
  background: var(--color-bg-soft);
}

.hero {
  display: flex;
  min-height: 760px;
  height: 100svh;
  max-height: 980px;
  padding-top: calc(var(--header-height) + 84px);
  padding-bottom: 52px;
  overflow: hidden;
}

.hero-grid {
  position: absolute;
  inset: 0;
  opacity: 0.28;
  background-image:
    linear-gradient(rgba(255, 255, 255, 0.035) 1px, transparent 1px),
    linear-gradient(90deg, rgba(255, 255, 255, 0.035) 1px, transparent 1px);
  background-size: 64px 64px;
  mask-image: linear-gradient(to bottom, black 15%, transparent 84%);
}

.hero-glow {
  position: absolute;
  top: 18%;
  left: 58%;
  width: 520px;
  height: 520px;
  border: 1px solid rgba(105, 183, 255, 0.08);
  border-radius: 50%;
  background: radial-gradient(circle, rgba(105, 183, 255, 0.08), transparent 66%);
  transform: translate(-50%, -30%);
}

.hero-glow::before,
.hero-glow::after {
  position: absolute;
  border: 1px solid rgba(105, 183, 255, 0.06);
  border-radius: inherit;
  content: "";
}

.hero-glow::before {
  inset: 72px;
}

.hero-glow::after {
  inset: 152px;
}

.hero-content {
  position: relative;
  z-index: 1;
  align-self: center;
  margin-top: -38px;
}

.eyebrow,
.section-number,
.note-type {
  margin: 0 0 22px;
  color: var(--color-accent);
  font-family: var(--font-sans);
  font-size: 0.72rem;
  letter-spacing: 0.06em;
  text-transform: uppercase;
}

.section-number {
  font-family: var(--font-mono);
  letter-spacing: 0.13em;
}

.status-dot {
  display: inline-block;
  width: 6px;
  height: 6px;
  margin-right: 10px;
  border-radius: 50%;
  background: var(--color-accent);
  box-shadow: 0 0 0 5px var(--color-accent-soft);
  vertical-align: 1px;
}

.hero h1 {
  max-width: 900px;
  margin: 0;
  font-size: clamp(4.2rem, 10vw, 8.4rem);
  font-weight: 650;
  letter-spacing: -0.045em;
  line-height: 1;
}

.hero-brand-cn {
  margin: 14px 0 0;
  color: var(--color-text-muted);
  font-family: var(--font-mono);
  font-size: clamp(0.72rem, 1.2vw, 0.9rem);
  letter-spacing: 0.16em;
  text-transform: uppercase;
}

.hero-tagline {
  max-width: 750px;
  margin: 42px 0 0;
  color: var(--color-text);
  font-size: clamp(1.3rem, 2.3vw, 2rem);
  font-weight: 450;
  letter-spacing: 0;
  line-height: 1.35;
}

.hero-intro {
  max-width: 650px;
  margin: 16px 0 0;
  color: var(--color-text-muted);
  font-size: 1.05rem;
}

.hero-actions {
  display: flex;
  gap: 12px;
  margin-top: 38px;
}

.button {
  display: inline-flex;
  min-height: 48px;
  padding: 0 22px;
  gap: 20px;
  align-items: center;
  justify-content: center;
  border: 1px solid transparent;
  border-radius: var(--radius);
  font-size: 0.86rem;
  font-weight: 650;
  transition: background-color 160ms ease, border-color 160ms ease, transform 160ms ease;
}

.button:hover {
  transform: translateY(-2px);
}

.button-primary {
  color: #07101a;
  background: var(--color-accent);
}

.button-primary:hover {
  background: #8bc7ff;
}

.button-secondary {
  border-color: var(--color-line-strong);
  background: rgba(255, 255, 255, 0.025);
}

.button-secondary:hover {
  border-color: rgba(255, 255, 255, 0.28);
  background: rgba(255, 255, 255, 0.055);
}

.hero-footnote {
  position: absolute;
  right: 0;
  bottom: 36px;
  left: 0;
  display: flex;
  gap: 18px;
  align-items: center;
  color: #657080;
  font-family: var(--font-mono);
  font-size: 0.65rem;
  letter-spacing: 0.13em;
}

.hero-line {
  height: 1px;
  flex: 1;
  background: var(--color-line);
}

.section-layout {
  display: grid;
  grid-template-columns: minmax(220px, 0.75fr) minmax(0, 1.65fr);
  gap: clamp(60px, 10vw, 150px);
}

.section-heading h2,
.contact h2 {
  margin: 0;
  font-size: clamp(2.4rem, 4.6vw, 4.5rem);
  font-weight: 580;
  letter-spacing: -0.025em;
  line-height: 1;
}

.section-heading-row {
  display: flex;
  align-items: flex-end;
  justify-content: space-between;
  margin-bottom: 54px;
}

.section-summary {
  max-width: 330px;
  margin: 26px 0 0;
  color: var(--color-text-muted);
  font-size: 0.94rem;
}

.about-copy {
  max-width: 740px;
}

.about-copy p {
  margin: 0 0 26px;
  color: var(--color-text-muted);
  font-size: 1.05rem;
}

.about-copy .lead {
  color: var(--color-text-soft);
  font-size: clamp(1.35rem, 2.5vw, 2rem);
  letter-spacing: 0;
  line-height: 1.6;
}

.focus-list {
  display: flex;
  flex-wrap: wrap;
  gap: 10px;
  margin-top: 42px;
}

.focus-list span {
  padding: 8px 13px;
  border: 1px solid var(--color-line);
  border-radius: 99px;
  color: var(--color-text-soft);
  font-family: var(--font-sans);
  font-size: 0.7rem;
  letter-spacing: 0;
}

.project-grid {
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  border-top: 1px solid var(--color-line);
  border-left: 1px solid var(--color-line);
}

.project-card {
  display: flex;
  min-height: 390px;
  padding: clamp(26px, 3vw, 38px);
  flex-direction: column;
  border-right: 1px solid var(--color-line);
  border-bottom: 1px solid var(--color-line);
  background: rgba(255, 255, 255, 0.012);
  transition: background-color 180ms ease;
}

.project-card:hover {
  background: var(--color-surface-hover);
}

.card-meta {
  display: flex;
  align-items: center;
  justify-content: space-between;
  color: var(--color-text-muted);
  font-family: var(--font-sans);
  font-size: 0.65rem;
  letter-spacing: 0.04em;
  text-transform: uppercase;
}

.status {
  padding: 5px 8px;
  border: 1px solid var(--color-line);
  color: var(--color-accent);
}

.project-card h3 {
  max-width: 260px;
  margin: 88px 0 18px;
  font-size: clamp(1.45rem, 2vw, 1.8rem);
  font-weight: 560;
  letter-spacing: -0.015em;
  line-height: 1.35;
}

.project-card p {
  margin: 0;
  color: var(--color-text-muted);
  font-size: 0.92rem;
  line-height: 1.8;
}

.card-link {
  display: flex;
  align-items: center;
  justify-content: space-between;
  margin-top: auto;
  padding-top: 32px;
  color: var(--color-text-soft);
  font-family: var(--font-sans);
  font-size: 0.7rem;
  letter-spacing: 0.04em;
  text-transform: uppercase;
}

.notes-list {
  border-top: 1px solid var(--color-line);
}

.note-card {
  display: flex;
  min-height: 150px;
  padding: 30px 0;
  align-items: center;
  justify-content: space-between;
  gap: 32px;
  border-bottom: 1px solid var(--color-line);
}

.note-card h3 {
  margin: 0;
  font-size: clamp(1.15rem, 2vw, 1.55rem);
  font-weight: 520;
  letter-spacing: -0.01em;
}

.note-type {
  margin-bottom: 8px;
}

.note-card > span {
  flex: 0 0 auto;
  color: var(--color-text-muted);
  font-family: var(--font-sans);
  font-size: 0.65rem;
  letter-spacing: 0.04em;
  text-transform: uppercase;
}

.contact {
  overflow: hidden;
  border-top: 1px solid var(--color-line);
  background: linear-gradient(115deg, var(--color-bg-soft), var(--color-bg));
}

.contact::after {
  position: absolute;
  top: -180px;
  right: -180px;
  width: 460px;
  height: 460px;
  border: 1px solid rgba(105, 183, 255, 0.08);
  border-radius: 50%;
  content: "";
}

.contact-inner {
  position: relative;
  z-index: 1;
  display: grid;
  grid-template-columns: minmax(220px, 0.75fr) minmax(0, 1.65fr);
  gap: clamp(60px, 10vw, 150px);
}

.contact-copy > p {
  max-width: 660px;
  margin: 0;
  color: var(--color-text-muted);
  font-size: clamp(1.35rem, 2.7vw, 2.1rem);
  letter-spacing: 0;
  line-height: 1.6;
}

.contact-copy .contact-emphasis {
  margin-top: 4px;
  color: var(--color-text);
}

.contact-links {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  margin-top: 58px;
  border-top: 1px solid var(--color-line);
  border-left: 1px solid var(--color-line);
}

.contact-links a {
  display: flex;
  min-width: 0;
  padding: 22px;
  flex-direction: column;
  border-right: 1px solid var(--color-line);
  border-bottom: 1px solid var(--color-line);
  font-weight: 600;
  transition: background-color 160ms ease;
}

.contact-links a:hover {
  background: var(--color-surface);
}

.contact-links span {
  margin-top: 5px;
  overflow-wrap: anywhere;
  color: var(--color-text-muted);
  font-family: var(--font-mono);
  font-size: 0.68rem;
  font-weight: 400;
}

.site-footer {
  border-top: 1px solid var(--color-line);
  color: var(--color-text-muted);
  background: #07090d;
}

.footer-inner {
  display: flex;
  min-height: 92px;
  align-items: center;
  justify-content: space-between;
  gap: 28px;
  font-size: 0.75rem;
}

.footer-inner p {
  margin: 0;
}

.legal-links {
  display: flex;
  gap: 20px;
  align-items: center;
}

.legal-links a:hover {
  color: var(--color-text);
}

a:focus-visible,
button:focus-visible {
  outline: 2px solid var(--color-accent);
  outline-offset: 4px;
}

@media (max-width: 900px) {
  .section {
    padding: 104px 0;
  }

  .section-layout,
  .contact-inner {
    grid-template-columns: 1fr;
    gap: 54px;
  }

  .project-grid {
    grid-template-columns: 1fr;
  }

  .project-card {
    min-height: 330px;
  }

  .project-card h3 {
    margin-top: 58px;
  }

  .section-summary {
    max-width: 290px;
  }
}

@media (max-width: 700px) {
  :root {
    --header-height: 68px;
  }

  .site-header.is-scrolled {
    background: var(--color-bg);
    -webkit-backdrop-filter: none;
    backdrop-filter: none;
  }

  .container {
    width: min(calc(100% - 34px), var(--container));
  }

  .nav-toggle {
    position: relative;
    z-index: 102;
    display: block;
  }

  .nav-toggle[aria-expanded="true"] span:first-child {
    transform: translateY(3px) rotate(45deg);
  }

  .nav-toggle[aria-expanded="true"] span:last-child {
    transform: translateY(-3px) rotate(-45deg);
  }

  .site-nav {
    position: fixed;
    z-index: 101;
    inset: 0;
    display: flex;
    min-height: 100vh;
    min-height: 100dvh;
    padding: 110px 24px 42px;
    flex-direction: column;
    align-items: stretch;
    justify-content: flex-start;
    gap: 4px;
    overflow-y: auto;
    visibility: hidden;
    background: var(--color-bg);
    opacity: 0;
    transform: translateY(-12px);
    transition: opacity 180ms ease, transform 180ms ease, visibility 180ms;
  }

  .site-nav.is-open {
    visibility: visible;
    opacity: 1;
    transform: translateY(0);
  }

  .site-nav a {
    padding: 12px 0;
    font-size: clamp(1.8rem, 8vw, 2.7rem);
    letter-spacing: -0.015em;
  }

  .site-nav a::after {
    display: none;
  }

  .section {
    padding: 84px 0;
  }

  .hero {
    min-height: 690px;
    height: 100svh;
    padding-top: calc(var(--header-height) + 70px);
    padding-bottom: 42px;
  }

  .hero-content {
    margin-top: -20px;
  }

  .hero h1 {
    font-size: clamp(3.7rem, 18vw, 5.7rem);
    letter-spacing: -0.045em;
  }

  .hero-tagline {
    margin-top: 30px;
  }

  .hero-intro {
    font-size: 0.95rem;
  }

  .hero-glow {
    top: 20%;
    left: 84%;
    width: 390px;
    height: 390px;
  }

  .hero-footnote {
    bottom: 24px;
  }

  .hero-footnote span:first-child {
    display: none;
  }

  .section-heading-row {
    display: block;
    margin-bottom: 36px;
  }

  .project-card {
    min-height: 310px;
    padding: 25px;
  }

  .project-card h3 {
    margin-top: 45px;
  }

  .note-card {
    min-height: 132px;
  }

  .contact-links {
    grid-template-columns: 1fr;
    margin-top: 42px;
  }

  .footer-inner {
    padding: 24px 0;
    flex-direction: column;
    align-items: flex-start;
    justify-content: center;
    gap: 10px;
  }

  .legal-links {
    flex-direction: column;
    align-items: flex-start;
    gap: 8px;
  }
}

@media (max-width: 410px) {
  .hero-actions {
    align-items: stretch;
    flex-direction: column;
  }

  .button {
    width: 100%;
  }

  .note-card {
    align-items: flex-start;
    flex-direction: column;
    gap: 12px;
  }
}

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

  *,
  *::before,
  *::after {
    scroll-behavior: auto !important;
    transition-duration: 0.01ms !important;
  }
}