:root {
  color-scheme: dark;
  /* 常改视觉参数：主强调色和左侧面板宽度。 */
  --accent: #ff3b3b;
  --text: #f4f2f3;
  --muted: #c9c5c7;
  --line: rgba(255, 255, 255, 0.14);
  --panel-width: clamp(27rem, 32vw, 36rem);
  --interface-font: "Bahnschrift", "Segoe UI Variable", "Segoe UI", "Microsoft YaHei UI", "PingFang SC", sans-serif;
  font-family: var(--interface-font);
}

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

html {
  min-width: 20rem;
  min-height: 100%;
  background: #08080b;
}

body {
  min-height: 100vh;
  min-height: 100svh;
  margin: 0;
  overflow-x: hidden;
  color: var(--text);
  background: #08080b;
}

a {
  color: inherit;
}

.skip-link {
  position: fixed;
  z-index: 20;
  top: 0.75rem;
  left: 0.75rem;
  padding: 0.7rem 1rem;
  color: #111;
  background: #fff;
  border-radius: 0.25rem;
  transform: translateY(-150%);
  transition: transform 160ms ease;
}

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

.site-background {
  position: fixed;
  z-index: 0;
  inset: 0;
  opacity: 0;
  background-color: #08080b;
  background-image: none;
  background-repeat: no-repeat;
  background-position: center;
  background-size: cover;
  filter: blur(0.65rem);
  transform: scale(1.035);
  transition:
    opacity 900ms ease,
    filter 1100ms ease,
    transform 1500ms cubic-bezier(0.22, 1, 0.36, 1);
  user-select: none;
  pointer-events: none;
}

.site-background.is-loaded {
  opacity: 1;
  filter: blur(0);
  transform: scale(1);
}

.background-shade {
  position: fixed;
  z-index: 1;
  inset: 0;
  pointer-events: none;
  background:
    linear-gradient(180deg, rgba(4, 4, 7, 0.22), transparent 24%, transparent 72%, rgba(4, 4, 7, 0.32)),
    linear-gradient(270deg, rgba(7, 5, 8, 0.96) 0%, rgba(8, 6, 9, 0.88) 22%, rgba(8, 6, 9, 0.55) 35%, rgba(8, 6, 9, 0.12) 58%, rgba(8, 6, 9, 0.03) 100%);
}

.site-panel {
  position: relative;
  z-index: 2;
  width: var(--panel-width);
  min-height: 100vh;
  min-height: 100svh;
  margin-left: auto;
  isolation: isolate;
}

.site-panel::after {
  position: absolute;
  z-index: -1;
  top: 0;
  right: 0;
  bottom: 0;
  left: -8rem;
  content: "";
  pointer-events: none;
  background: linear-gradient(270deg, rgba(7, 5, 8, 0.54), rgba(7, 5, 8, 0.2) 72%, transparent);
}

.site-panel__inner {
  display: flex;
  flex-direction: column;
  min-height: 100vh;
  min-height: 100svh;
  padding: clamp(2rem, 4.4vh, 3.4rem) clamp(2rem, 3vw, 3.2rem) clamp(1.5rem, 3.2vh, 2.4rem);
}

.brand {
  display: flex;
  align-items: center;
  gap: 0.95rem;
  margin-bottom: clamp(2rem, 5vh, 4.5rem);
  font-size: clamp(0.82rem, 1vw, 1.02rem);
  font-weight: 500;
  letter-spacing: 0.28em;
  white-space: nowrap;
}

.brand__mark {
  width: 0.72rem;
  height: 0.72rem;
  flex: 0 0 auto;
  background: var(--accent);
  box-shadow: 0 0 1.2rem rgba(255, 59, 59, 0.24);
}

.intro__title {
  display: flex;
  flex-direction: column;
  margin: 0;
  font-family: "Bahnschrift Condensed", "Arial Narrow", Impact, sans-serif;
  font-size: clamp(3.4rem, 4.5vw, 5.3rem);
  font-stretch: condensed;
  font-weight: 700;
  line-height: 0.94;
  letter-spacing: 0.01em;
  text-transform: uppercase;
  text-shadow: 0 0.15rem 1rem rgba(0, 0, 0, 0.32);
}

.intro__accent {
  width: 6.4rem;
  height: 0.18rem;
  margin: clamp(1.3rem, 2.5vh, 2rem) 0 clamp(1.8rem, 3.4vh, 2.6rem);
  background: var(--accent);
}

.contact-list {
  display: grid;
  gap: 0.55rem;
  margin: 0;
  font-family: var(--interface-font);
  font-size: clamp(0.82rem, 1vw, 1rem);
  font-weight: 400;
  line-height: 1.45;
  letter-spacing: 0.025em;
  color: var(--muted);
}

.contact-list__row {
  display: grid;
  grid-template-columns: max-content 1fr;
  gap: 0.65rem;
  min-width: 0;
}

.contact-list dt,
.contact-list dd {
  margin: 0;
}

.contact-list dd,
.contact-list a {
  min-width: 0;
  overflow-wrap: anywhere;
  color: var(--text);
  font-weight: 600;
  text-decoration: none;
}

.contact-list a:hover {
  color: #fff;
  text-decoration: underline;
  text-decoration-color: var(--accent);
  text-underline-offset: 0.24em;
}

.quick-nav {
  margin-top: clamp(1.3rem, 3vh, 2.3rem);
  border-top: 1px solid var(--line);
}

.quick-nav__list {
  margin: 0;
  padding: 0;
  list-style: none;
}

.quick-nav li {
  border-bottom: 1px solid var(--line);
}

.quick-nav a {
  display: grid;
  grid-template-columns: 3.4rem 1fr 1.5rem;
  align-items: center;
  min-height: clamp(3.8rem, 7.2vh, 4.7rem);
  text-decoration: none;
  transition: color 160ms ease, padding-left 160ms ease, background-color 160ms ease;
}

.quick-nav__number {
  font-family: "Bahnschrift Condensed", "Arial Narrow", Impact, sans-serif;
  font-size: clamp(1.75rem, 2.4vw, 2.4rem);
  font-weight: 650;
  line-height: 1;
}

.quick-nav__label {
  font-family: var(--interface-font);
  font-size: clamp(0.86rem, 1.05vw, 1.03rem);
  font-weight: 600;
  letter-spacing: 0.025em;
}

.quick-nav__arrow {
  justify-self: end;
  font-size: 1.35rem;
  line-height: 1;
}

.quick-nav li:first-child a,
.quick-nav a:hover {
  color: var(--accent);
}

.quick-nav a:hover {
  padding-left: 0.45rem;
  background: linear-gradient(90deg, rgba(255, 59, 59, 0.08), transparent 70%);
}

.quick-nav a:focus-visible,
.site-footer a:focus-visible,
.contact-list a:focus-visible,
.site-note summary:focus-visible,
.error-home:focus-visible {
  outline: 2px solid #fff;
  outline-offset: 0.25rem;
}

.site-footer {
  margin-top: auto;
  padding-top: clamp(1.25rem, 3vh, 2rem);
  color: rgba(244, 242, 243, 0.68);
  font-size: clamp(0.64rem, 0.68vw, 0.75rem);
  line-height: 1.6;
}

.site-footer__legal {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 0.25rem 0.55rem;
  margin: 0;
}

/* 页面加载时按信息层级依次展开，保持布局稳定且不依赖脚本。 */
@keyframes content-reveal {
  from {
    opacity: 0;
    clip-path: inset(0 100% 0 0);
    transform: translate3d(-1rem, 0, 0);
  }

  to {
    opacity: 1;
    clip-path: inset(0 0 0 0);
    transform: translate3d(0, 0, 0);
  }
}

@keyframes accent-reveal {
  from {
    opacity: 0;
    transform: scaleX(0);
  }

  to {
    opacity: 1;
    transform: scaleX(1);
  }
}

.brand,
.intro__title,
.contact-list__row,
.quick-nav__list > li,
.site-footer {
  animation: content-reveal 620ms cubic-bezier(0.22, 1, 0.36, 1) both;
}

.brand {
  animation-delay: 40ms;
}

.intro__title {
  animation-delay: 110ms;
}

.intro__accent {
  transform-origin: left center;
  animation: accent-reveal 520ms cubic-bezier(0.22, 1, 0.36, 1) 220ms both;
}

.contact-list__row:nth-child(1) {
  animation-delay: 270ms;
}

.contact-list__row:nth-child(2) {
  animation-delay: 330ms;
}

.contact-list__row:nth-child(3) {
  animation-delay: 390ms;
}

.quick-nav__list > li:nth-child(1) {
  animation-delay: 430ms;
}

.quick-nav__list > li:nth-child(2) {
  animation-delay: 480ms;
}

.quick-nav__list > li:nth-child(3) {
  animation-delay: 530ms;
}

.quick-nav__list > li:nth-child(4) {
  animation-delay: 580ms;
}

.quick-nav__list > li:nth-child(5) {
  animation-delay: 630ms;
}

.quick-nav__list > li:nth-child(6) {
  animation-delay: 680ms;
}

.site-footer {
  animation-delay: 760ms;
}

.site-footer a {
  text-decoration: none;
}

.site-footer a:hover {
  color: #fff;
}

.site-footer__divider {
  color: rgba(255, 255, 255, 0.28);
}

.site-note {
  margin-top: 0.5rem;
  max-width: 31rem;
}

.site-note summary {
  width: max-content;
  cursor: pointer;
  color: rgba(244, 242, 243, 0.58);
}

.site-note p {
  margin: 0.45rem 0 0;
  color: rgba(244, 242, 243, 0.62);
}

.error-page .background-shade {
  background: linear-gradient(90deg, rgba(7, 5, 8, 0.95), rgba(7, 5, 8, 0.72) 38%, rgba(7, 5, 8, 0.2));
}

.error-panel {
  position: relative;
  z-index: 2;
  display: grid;
  min-height: 100vh;
  min-height: 100svh;
  align-content: center;
  width: min(90%, 34rem);
  padding: 3rem;
}

.error-code {
  margin: 0;
  color: var(--accent);
  font-family: "Bahnschrift Condensed", "Arial Narrow", Impact, sans-serif;
  font-size: clamp(5rem, 15vw, 10rem);
  line-height: 0.82;
}

.error-title {
  margin: 1.5rem 0 0.7rem;
  font-size: clamp(1.5rem, 3vw, 2.3rem);
}

.error-copy {
  max-width: 28rem;
  margin: 0;
  color: var(--muted);
}

.error-home {
  width: max-content;
  margin-top: 2rem;
  padding-bottom: 0.3rem;
  color: #fff;
  border-bottom: 2px solid var(--accent);
  text-decoration: none;
}

@media (max-height: 800px) and (min-width: 761px) {
  .site-panel__inner {
    padding-top: 1.6rem;
    padding-bottom: 1.1rem;
  }

  .brand {
    margin-bottom: 1.35rem;
  }

  .intro__title {
    font-size: clamp(3rem, 4.2vw, 4.25rem);
  }

  .intro__accent {
    margin: 1rem 0 1.3rem;
  }

  .contact-list {
    gap: 0.28rem;
  }

  .quick-nav {
    margin-top: 1rem;
  }

  .quick-nav a {
    min-height: 3.35rem;
  }

  .site-footer {
    padding-top: 0.85rem;
  }

  .site-note {
    display: none;
  }
}

@media (max-width: 760px) {
  :root {
    --panel-width: 100%;
  }

  body {
    overflow-y: auto;
  }

  .site-background {
    background-position: 44% center;
  }

  .background-shade {
    background:
      linear-gradient(180deg, rgba(5, 5, 8, 0.78), rgba(5, 5, 8, 0.62) 56%, rgba(5, 5, 8, 0.86)),
      linear-gradient(90deg, rgba(8, 6, 9, 0.7), rgba(8, 6, 9, 0.28));
  }

  .site-panel::after {
    right: 0;
    left: 0;
    background: linear-gradient(180deg, rgba(7, 5, 8, 0.32), rgba(7, 5, 8, 0.58));
  }

  .site-panel__inner {
    padding: 2rem clamp(1.25rem, 7vw, 2.5rem) 1.5rem;
  }

  .brand {
    margin-bottom: 2.8rem;
  }

  .intro__title {
    font-size: clamp(3.1rem, 17vw, 5rem);
  }

  .contact-list {
    font-size: clamp(0.78rem, 3.4vw, 0.96rem);
  }

  .quick-nav a {
    grid-template-columns: 3.2rem 1fr 1.5rem;
    min-height: 4.1rem;
  }

  .site-footer {
    margin-top: 2.4rem;
    font-size: 0.68rem;
  }

  .site-footer__divider {
    display: none;
  }
}

@media (prefers-reduced-motion: reduce) {
  *,
  *::before,
  *::after {
    scroll-behavior: auto !important;
    animation-duration: 0.01ms !important;
    animation-delay: 0ms !important;
    transition-duration: 0.01ms !important;
  }
}