:root, [data-theme="dark"] {
  --bg: #030305;
  --bg-deep: #010102;
  --surface: rgba(255, 255, 255, 0.04);
  --surface-strong: rgba(255, 255, 255, 0.07);
  --border: rgba(255, 255, 255, 0.08);
  --border-hover: rgba(255, 255, 255, 0.18);
  --ice: #c4b8ce;
  --silver: rgb(255, 252, 225);
  --violet: #b8a8c8;
  --ice-dim: rgba(196, 184, 206, 0.65);
  --silver-dim: rgba(232, 238, 245, 0.55);
  --violet-dim: rgba(184, 168, 200, 0.5);
  --header-bg: rgba(3, 3, 5, 0.65);
  --footer-bg: rgba(3, 3, 5, 0.7);
  --star-color: 255, 252, 225;
  --nebula-1: rgba(196, 184, 206, 0.14);
  --nebula-2: rgba(184, 168, 200, 0.1);
  --nebula-3: rgba(196, 184, 206, 0.06);

  --radius: 1rem;
  --font-display: "Space Grotesk", "Inter", -apple-system, BlinkMacSystemFont, sans-serif;
  --font-body: "Inter", -apple-system, BlinkMacSystemFont, "Segoe UI", sans-serif;
}

[data-theme="light"] {
  --bg: #efeeeb;
  --bg-deep: #efeeeb;
  --surface: rgba(36, 38, 43, 0.035);
  --surface-strong: rgba(36, 38, 43, 0.06);
  --border: rgba(36, 38, 43, 0.1);
  --border-hover: rgba(36, 38, 43, 0.22);
  --ice: #70687a;
  --silver: #24262b;
  --violet: #6e627a;
  --ice-dim: rgba(112, 104, 122, 0.72);
  --silver-dim: rgba(36, 38, 43, 0.62);
  --violet-dim: rgba(110, 98, 122, 0.55);
  --header-bg: #efeeeb;
  --footer-bg: #efeeeb;
  --star-color: 115, 118, 125;
  --nebula-1: rgba(112, 104, 122, 0.1);
  --nebula-2: rgba(110, 98, 122, 0.08);
  --nebula-3: rgba(112, 104, 122, 0.06);
}

* {
  margin: 0;
  padding: 0;
  box-sizing: border-box;
}

html {
  scroll-behavior: smooth;
}

body {
  font-family: var(--font-body);
  font-weight: 300;
  line-height: 1.7;
  color: var(--silver);
  background: var(--bg);
  min-height: 100vh;
  overflow-x: hidden;
  transition: color 0.4s ease, background 0.4s ease;
}



/* 顶部导航 */
.site-header {
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  z-index: 100;
  padding: 1rem 4vw;
  background: var(--header-bg);
  backdrop-filter: blur(16px);
  -webkit-backdrop-filter: blur(16px);
  border-bottom: 1px solid var(--border);
  transition: background 0.4s ease, border-color 0.4s ease;
}

.nav-bar {
  max-width: 1280px;
  margin: 0 auto;
  display: flex;
  align-items: center;
  justify-content: space-between;
}

.brand {
  display: inline-flex;
  align-items: center;
  gap: 0.6rem;
  text-decoration: none;
  color: var(--silver);
  font-family: var(--font-display);
  font-weight: 400;
  font-size: 1.15rem;
  letter-spacing: 0.04em;
}

.brand-mark {
  color: var(--ice);
  opacity: 0.9;
  display: inline-flex;
  align-items: center;
}

.brand-mark svg {
  width: 1.1rem;
  height: 1.1rem;
  display: block;
}

.nav-right {
  display: flex;
  align-items: center;
  gap: 0.8rem;
}

/* 汉堡按钮 */
.menu-toggle {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  width: 2.2rem;
  height: 2.2rem;
  padding: 0;
  border: 1px solid var(--border);
  border-radius: 2px;
  background: var(--surface);
  color: var(--silver-dim);
  cursor: pointer;
  transition: border-color 0.3s ease, background 0.3s ease, color 0.3s ease;
}

.menu-toggle:hover {
  border-color: var(--border-hover);
  color: var(--ice);
  background: var(--surface-strong);
}

.menu-toggle svg {
  display: block;
}

/* 主题切换 */
.theme-toggle {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  width: 2.2rem;
  height: 2.2rem;
  padding: 0;
  border: 1px solid var(--border);
  border-radius: 2px;
  background: var(--surface);
  color: var(--silver-dim);
  cursor: pointer;
  transition: border-color 0.3s ease, background 0.3s ease, color 0.3s ease;
}

.theme-toggle:hover {
  border-color: var(--border-hover);
  color: var(--ice);
  background: var(--surface-strong);
}

.theme-icon {
  display: none;
  font-size: 0.95rem;
  line-height: 1;
}

[data-theme="dark"] .theme-icon-dark,
[data-theme="light"] .theme-icon-light {
  display: block;
}

/* 主内容区 */
main {
  position: relative;
  z-index: 1;
}

/* Hero 主视觉 — 参考 abc 布局，三段严格贴窗口四角 */
.hero {
  position: relative;
  width: 100%;
  height: 100vh;
  overflow: hidden;
  padding: 0;
  margin: 0;
  max-width: none;
}

.hero-orbit {
  position: absolute;
  inset: 0;
  display: flex;
  align-items: center;
  justify-content: center;
  opacity: 0.8;
  z-index: 1;
}

.orbit-system {
  width: min(90vh, 90vw);
  height: min(90vh, 90vw);
  max-width: 900px;
  max-height: 900px;
  will-change: transform; /* 呼吸动画走独立合成层，避免逐帧重绘 */
}

.orbit-system circle[stroke],
.orbit-system ellipse[stroke],
.orbit-system path[stroke] {
  transition: stroke 0.6s ease;
}

.hero-content {
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  bottom: 0;
  z-index: 2;
}

.hero-title {
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  bottom: 0;
  font-family: var(--font-display);
  font-size: clamp(2.8rem, 8vw, 6.5rem);
  font-weight: 300;
  line-height: 1;
  letter-spacing: -0.04em;
  color: var(--silver);
}

.title-word {
  position: absolute;
  display: inline-block;
  line-height: 1;
}

.title-deep {
  top: 0;
  left: 0;
  margin-top: -0.05em; /* 消除字体上方留白，紧贴窗口左上角 */
  transform: translateX(2%); /* 防止左侧笔画被裁 */
}

.title-white {
  top: 50%;
  left: 50%;
  transform: translate(-50%, -50%);
  color: var(--silver-dim);
  font-weight: 200;
  padding: 0.12em 0.3em;
  border-radius: 2px;
  z-index: 1;
}

.title-x {
  right: 0;
  bottom: 0;
  margin-bottom: -0.05em; /* 抵消字体底部下沉留白，紧贴窗口右下角 */
  color: var(--ice);
  font-weight: 400;
  transform: translateX(-2%); /* 防止右侧笔画被裁 */
}

.hero-divider {
  position: absolute;
  right: 4vw;
  bottom: 26%;
  display: flex;
  align-items: center;
  gap: 0.7rem;
}

.hero-divider-line {
  display: block;
  width: 3.2rem;
  height: 1px;
  background: var(--border-hover);
}

.hero-divider-dot {
  display: block;
  width: 4px;
  height: 4px;
  border-radius: 50%;
  background: var(--ice-dim);
}

.hero-subtitle {
  position: absolute;
  right: 4vw;
  bottom: 16%;
  font-size: clamp(1rem, 1.8vw, 1.15rem);
  color: var(--silver-dim);
  line-height: 1.85;
  font-weight: 300;
  max-width: 420px;
  text-align: right;
}

.hero-actions {
  position: absolute;
  bottom: 6%;
  right: 4vw;
  display: flex;
  gap: 1rem;
  justify-content: flex-end;
  flex-wrap: wrap;
}

/* Lead 引语 — hero 下方的独立盒子 */
.lead {
  text-align: left;
  padding: 5rem 4vw;
  max-width: 1280px;
  margin: 0 auto;
}

.lead-text {
  font-size: clamp(1rem, 1.8vw, 1.15rem);
  color: var(--silver-dim);
  line-height: 1.85;
  font-weight: 300;
  max-width: 520px;
}

.lead-actions {
  margin-top: 2rem;
  display: flex;
  gap: 1rem;
  justify-content: flex-start;
  flex-wrap: wrap;
}

/* 按钮 — 克制几何，无胶囊/无发光 */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  padding: 0.75rem 2rem;
  border-radius: 2px;
  font-family: var(--font-display);
  font-size: 0.78rem;
  font-weight: 400;
  letter-spacing: 0.12em;
  text-transform: uppercase;
  text-decoration: none;
  transition: color 0.3s ease, border-color 0.3s ease, background 0.3s ease;
  cursor: pointer;
  border: 1px solid transparent;
}

.btn-primary {
  background: var(--surface);
  color: var(--silver);
  border-color: var(--border-hover);
}

.btn-primary:hover {
  background: var(--surface-strong);
  color: var(--ice);
  border-color: var(--ice-dim);
}

.btn-ghost {
  background: transparent;
  color: var(--silver-dim);
  border-color: var(--border);
}

.btn-ghost:hover {
  color: var(--silver);
  border-color: var(--border-hover);
  background: var(--surface);
}

.btn-mail {
  background: var(--bg-deep);
  color: var(--silver);
  border-color: var(--border-hover);
  flex-shrink: 0;
}

.btn-mail:hover {
  background: var(--surface);
  color: var(--ice);
  border-color: var(--ice-dim);
}

.apply-row {
  display: flex;
  gap: 0.75rem;
  margin-top: 1.25rem;
  flex-wrap: wrap;
}

.apply-input {
  flex: 1 1 220px;
  max-width: 360px;
  min-width: 220px;
  background: var(--surface);
  border: 1px solid var(--border);
  color: var(--silver);
  padding: 0.75rem 1rem;
  border-radius: 2px;
  font-family: var(--font-body);
  font-size: 0.85rem;
  font-weight: 300;
  outline: none;
  transition: border-color 0.3s ease, background 0.3s ease;
}

.apply-input::placeholder {
  color: var(--silver-dim);
}

.apply-input:focus {
  border-color: var(--border-hover);
  background: var(--surface-strong);
}

/* 通用区块 */
section {
  padding: 5rem 4vw;
  max-width: 1280px;
  margin: 0 auto;
}

.section-head {
  text-align: left;
  margin-bottom: 3rem;
}

.section-index {
  display: inline-block;
  font-family: var(--font-display);
  font-size: 0.75rem;
  letter-spacing: 0.25em;
  color: var(--ice-dim);
  margin-bottom: 0.8rem;
}

.section-title {
  font-family: var(--font-display);
  font-size: clamp(1.8rem, 4vw, 2.6rem);
  font-weight: 300;
  color: var(--silver);
  margin-bottom: 0.8rem;
}

.section-desc {
  color: var(--silver-dim);
  max-width: 520px;
  font-size: 1rem;
}

/* Mission 理念 — 纯文本流，类 Markdown */
.mission h2 {
  font-family: var(--font-display);
  font-size: clamp(1.8rem, 4vw, 2.6rem);
  font-weight: 300;
  color: var(--silver);
  margin-bottom: 0.6rem;
}

.mission h2 + p {
  color: var(--silver-dim);
  font-size: 1rem;
  margin-bottom: 2rem;
  max-width: 520px;
}

.mission p {
  color: var(--silver-dim);
  font-size: 0.95rem;
  line-height: 1.75;
  padding: 0.6rem 0;
}

.mission p strong {
  font-family: var(--font-display);
  font-weight: 400;
  color: var(--silver);
}

/* Explore 轨迹 */
.explore-visual {
  position: absolute;
  top: 0;
  left: 0;
  width: 100%;
  height: 100%;
  pointer-events: none;
  opacity: 0.35;
  z-index: 0;
}

.explore {
  position: relative;
  z-index: 1;
}

.explore .section-head,
.explore .site-list {
  position: relative;
  z-index: 1;
}

.trajectory {
  width: 100%;
  height: 100%;
  overflow: visible;
}

.site-list {
  display: flex;
  flex-direction: column;
  list-style: none;
  border-top: 1px solid var(--border);
}

.site-list-item {
  border-bottom: 1px solid var(--border);
}

.site-list-item a {
  display: flex;
  align-items: baseline;
  justify-content: space-between;
  gap: 1.5rem;
  padding: 1.2rem 0;
  text-decoration: none;
  color: inherit;
  transition: color 0.3s ease;
}

.site-list-item a:hover {
  color: var(--ice);
}

.site-list-item a[aria-disabled="true"] {
  pointer-events: none;
}

.site-list-item h4 {
  font-family: var(--font-display);
  font-weight: 400;
  font-size: 1.1rem;
  color: var(--silver);
  flex-shrink: 0;
}

.site-list-item p {
  color: var(--silver-dim);
  font-size: 0.92rem;
  line-height: 1.5;
  text-align: right;
}

@media (max-width: 640px) {
  .site-list-item a {
    flex-direction: column;
    gap: 0.3rem;
  }

  .site-list-item p {
    text-align: left;
  }
}

/* 页脚 */
.site-footer {
  position: relative;
  z-index: 1;
  padding: 3.5rem 4vw;
  border-top: 1px solid var(--border);
  background: var(--footer-bg);
  backdrop-filter: blur(8px);
  -webkit-backdrop-filter: blur(8px);
  transition: background 0.4s ease, border-color 0.4s ease;
}

.footer-inner {
  max-width: 1280px;
  margin: 0 auto;
  display: flex;
  justify-content: space-between;
  align-items: flex-end;
  gap: 2rem;
}

.footer-left {
  display: flex;
  flex-direction: column;
  gap: 0.4rem;
}

.footer-right {
  display: flex;
  flex-direction: column;
  align-items: flex-end;
  gap: 0.45rem;
  text-align: right;
}

.footer-brand {
  font-family: var(--font-display);
  font-size: 0.95rem;
  font-weight: 400;
  letter-spacing: 0.16em;
  text-transform: uppercase;
  color: var(--silver);
  opacity: 0.9;
  margin: 0;
}

.footer-slogan {
  font-size: 0.76rem;
  font-weight: 300;
  letter-spacing: 0.1em;
  color: var(--silver-dim);
  margin: 0;
  opacity: 0.75;
}

.footer-copy {
  font-size: 0.76rem;
  font-weight: 300;
  letter-spacing: 0.05em;
  color: var(--silver-dim);
  margin: 0;
}

.footer-beian {
  font-size: 0.72rem;
  font-weight: 300;
  letter-spacing: 0.08em;
  color: var(--ice-dim);
  text-decoration: none;
  margin: 0;
}

.footer-beian:hover {
  color: var(--ice);
}

/* 响应式 */
@media (max-width: 768px) {
  .site-header {
    padding: 0.85rem 4vw;
  }

  .nav-right {
    gap: 0.5rem;
  }

  .hero {
    padding: 0;
  }

  .hero-content {
    max-width: 100%;
  }

  .title-deep,
  .title-white,
  .title-x {
    align-self: flex-start;
  }

  .title-x {
    transform: none;
  }

  .hero-divider {
    right: auto;
    left: 6vw;
    justify-content: flex-start;
  }

  section {
    padding: 4rem 4vw;
  }

  .footer-inner {
    flex-direction: column;
    align-items: center;
    text-align: center;
    gap: 1.25rem;
  }

  .footer-right {
    align-items: center;
    text-align: center;
  }

  /* 导航面板在手机上更窄边距 */
  .nav {
    padding: 0.6rem;
  }

  .nav-panel {
    max-width: none;
  }

  .nav-top {
    padding: 4.5rem 1.5rem 1.5rem;
  }
}

/* 自定义滚动条 */
::-webkit-scrollbar {
  width: 8px;
}

::-webkit-scrollbar-track {
  background: var(--bg);
}

::-webkit-scrollbar-thumb {
  background: var(--border-hover);
  border-radius: 4px;
}

::-webkit-scrollbar-thumb:hover {
  background: var(--silver-dim);
}

/* ── 全屏导航覆盖层 ── */
.nav {
  position: fixed;
  inset: 0;
  z-index: 200;
  padding: 1rem;
  pointer-events: none;
  visibility: hidden;
  display: flex;
  flex-direction: column;
  align-items: flex-end;
  gap: 0.5rem;
}

.nav-bg {
  position: absolute;
  inset: 0;
  background: rgba(0, 0, 0, 0.35);
  backdrop-filter: blur(2px);
  -webkit-backdrop-filter: blur(2px);
  opacity: 0;
}

.nav-panel {
  width: 100%;
  max-width: 480px;
  border: 1px solid var(--border);
  border-radius: 10px;
  background: var(--bg);
  color: var(--silver);
}

/* 顶层面板 — 导航链接 */
.nav-top {
  flex: 1;
  display: flex;
  flex-direction: column;
  padding: 5rem 2rem 2rem;
}

.nav-list {
  list-style: none;
  display: flex;
  flex-direction: column;
  justify-content: center;
  flex: 1;
  gap: 0;
}

.nav-item {
  overflow: hidden;
}

.nav-link {
  display: block;
  text-decoration: none;
  color: var(--silver);
  padding: 0.7rem 0;
  font-family: var(--font-display);
  font-size: clamp(1.3rem, 3.5vw, 1.7rem);
  font-weight: 300;
  line-height: 1.2;
  letter-spacing: -0.02em;
  transition: color 0.3s ease;
}


/* 中间面板 — 信条 */
.nav-middle {
  padding: 1.5rem 2rem;
  background: radial-gradient(ellipse at 30% 40%, var(--nebula-1) 0%, transparent 65%),
              var(--surface);
}

.nav-middle-header {
  font-family: var(--font-display);
  font-size: 0.7rem;
  text-transform: uppercase;
  letter-spacing: 0.15em;
  color: var(--ice-dim);
  margin-bottom: 0.6rem;
}

.nav-middle-content {
  display: flex;
  flex-direction: column;
  gap: 0.3rem;
}

.nav-middle-title {
  font-family: var(--font-display);
  font-size: clamp(1rem, 2.5vw, 1.2rem);
  font-weight: 400;
  line-height: 1.3;
  color: var(--silver);
}

.nav-middle-desc {
  font-size: 0.85rem;
  color: var(--silver-dim);
  line-height: 1.5;
}

/* 底部面板 — 社交 */
.nav-bottom {
  display: flex;
  align-items: center;
  padding: 1rem 2rem;
  background: var(--bg-deep);
}

.nav-socials {
  list-style: none;
  display: flex;
  gap: 1.2rem;
}

.nav-socials a {
  font-family: var(--font-display);
  font-size: 0.8rem;
  color: var(--silver-dim);
  text-decoration: none;
  transition: color 0.3s ease;
}

.nav-socials a:hover {
  color: var(--ice);
}

.nav-copy {
  margin-left: auto;
  font-size: 0.75rem;
  color: var(--silver-dim);
  font-family: var(--font-display);
}

/* 亮色主题微调 */
[data-theme="light"] .nav {
  --nav-panel-bg: var(--bg);
}

[data-theme="light"] .nav-bg {
  background: rgba(0, 0, 0, 0.15);
}

[data-theme="light"] .nav-bottom {
  background: var(--surface);
}

/* 暗色模式下导航面板护眼适配：降低对比、柔化背景 */
[data-theme="dark"] .nav-panel {
  background: linear-gradient(180deg, rgba(255,255,255,0.02), rgba(255,255,255,0.0)),
              var(--bg);
  border-color: rgba(255,255,255,0.05);
  box-shadow: 0 18px 40px rgba(0,0,0,0.45);
}

[data-theme="dark"] .nav-top {
  background: linear-gradient(160deg, rgba(196,184,206,0.03), rgba(184,168,200,0.02)),
              var(--bg);
}

[data-theme="dark"] .nav-middle {
  background: radial-gradient(ellipse at 30% 40%, rgba(196,184,206,0.08) 0%, transparent 65%),
              linear-gradient(180deg, rgba(255,255,255,0.04), rgba(255,255,255,0.0)),
              var(--bg);
}

[data-theme="dark"] .nav-bottom {
  background: linear-gradient(180deg, rgba(255,255,255,0.025), rgba(255,255,255,0.0)),
              var(--bg-deep);
}

[data-theme="dark"] .nav-link {
  color: rgba(232,238,245,0.78);
}

[data-theme="dark"] .nav-link:hover {
  color: var(--ice);
}

[data-theme="dark"] .nav-middle-title {
  color: rgba(255,252,225,0.88);
}

[data-theme="dark"] .nav-middle-header {
  color: rgba(196,184,206,0.5);
}

/* 减弱动画偏好 */
@media (prefers-reduced-motion: reduce) {
  *,
  *::before,
  *::after {
    animation-duration: 0.01ms !important;
    animation-iteration-count: 1 !important;
    transition-duration: 0.01ms !important;
  }
}