:root {
  --spring: #10B981;
  --summer: #0EA5E9;
  --autumn: #F59E0B;
  --winter: #F8FAFC;
  --night: #0F172A;
  --night-soft: #1E293B;
  --night-deep: #0B1120;
  --ink: #1F2937;
  --muted: #64748B;
  --line: #E5E7EB;
  --radius-lg: 24px;
  --radius-md: 16px;
  --radius-pill: 999px;
  --shadow-xl: 0 20px 40px -20px rgba(2, 6, 23, 0.4);
  --font-sans: 'Inter', 'Noto Sans SC', 'PingFang SC', 'Microsoft YaHei', sans-serif;
  --font-mono: 'JetBrains Mono', 'SFMono-Regular', Consolas, monospace;
  --header-w: 280px;
  --nav-h: 64px;
}

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

html {
  scroll-behavior: smooth;
  -webkit-font-smoothing: antialiased;
  text-rendering: optimizeLegibility;
}

body {
  font-family: var(--font-sans);
  font-size: 16px;
  line-height: 1.7;
  color: var(--ink);
  background: var(--winter);
  min-height: 100vh;
}

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

a {
  color: var(--summer);
  text-decoration: none;
  transition: color 0.2s ease;
}

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

ul,
ol {
  list-style: none;
}

:focus-visible {
  outline: 2px solid var(--summer);
  outline-offset: 3px;
  border-radius: 4px;
}

.sr-only {
  position: absolute;
  width: 1px;
  height: 1px;
  padding: 0;
  margin: -1px;
  overflow: hidden;
  clip: rect(0, 0, 0, 0);
  white-space: nowrap;
  border: 0;
}

.skip-link {
  position: fixed;
  top: -80px;
  left: 16px;
  z-index: 1000;
  background: var(--winter);
  color: var(--ink);
  padding: 8px 20px;
  border-radius: var(--radius-pill);
  font-weight: 600;
  box-shadow: var(--shadow-xl);
  transition: top 0.2s ease;
}

.skip-link:focus-visible {
  top: 16px;
}

.scroll-progress {
  position: fixed;
  top: 0;
  left: 0;
  height: 3px;
  width: 0%;
  background: linear-gradient(90deg, var(--spring), var(--summer), var(--autumn));
  z-index: 999;
  border-radius: 0 var(--radius-pill) var(--radius-pill) 0;
  transition: width 0.1s linear;
}

.site-header {
  position: fixed;
  top: 0;
  left: 0;
  bottom: 0;
  width: var(--header-w);
  background: linear-gradient(160deg, var(--night-deep) 0%, var(--night-soft) 100%);
  border-right: 1px solid rgba(255, 255, 255, 0.06);
  padding: 32px 24px;
  display: flex;
  flex-direction: column;
  z-index: 500;
  overflow: hidden;
}

.header-glow {
  position: absolute;
  top: -80px;
  right: -80px;
  width: 200px;
  height: 200px;
  background: radial-gradient(circle, rgba(16, 185, 129, 0.12) 0%, transparent 70%);
  pointer-events: none;
}

.brand__link {
  display: inline-flex;
  text-decoration: none;
  border-radius: var(--radius-lg);
}

.brand {
  display: flex;
  align-items: center;
  gap: 12px;
}

.brand__mark {
  width: 44px;
  height: 44px;
  background: linear-gradient(135deg, var(--spring), var(--summer));
  border-radius: 14px;
  display: inline-flex;
  align-items: center;
  justify-content: center;
  color: #fff;
  font-size: 20px;
  font-weight: 900;
  letter-spacing: 0.04em;
  box-shadow: 0 8px 20px -6px rgba(16, 185, 129, 0.4);
  transition: transform 0.3s ease, box-shadow 0.3s ease;
  flex-shrink: 0;
}

.brand__link:hover .brand__mark {
  transform: translateY(-2px) rotate(-4deg);
  box-shadow: 0 12px 24px -8px rgba(14, 165, 233, 0.5);
}

.brand__text {
  display: flex;
  flex-direction: column;
  line-height: 1.4;
}

.brand__name {
  font-size: 18px;
  font-weight: 700;
  color: var(--winter);
  letter-spacing: 0.02em;
}

.brand__desc {
  font-size: 12px;
  font-family: var(--font-mono);
  color: #94A3B8;
  letter-spacing: 0.01em;
}

.site-nav {
  margin-top: 40px;
}

.nav-list {
  display: flex;
  flex-direction: column;
  gap: 4px;
}

.nav-list__link {
  display: flex;
  align-items: center;
  gap: 12px;
  padding: 12px 16px;
  color: #94A3B8;
  font-weight: 500;
  border-radius: var(--radius-pill);
  transition: background 0.2s ease, color 0.2s ease, transform 0.2s ease;
}

.nav-list__link:hover {
  color: var(--winter);
  background: rgba(255, 255, 255, 0.04);
  transform: translateX(4px);
}

.nav-list__link[aria-current="page"] {
  color: #fff;
  background: linear-gradient(90deg, rgba(16, 185, 129, 0.2), rgba(14, 165, 233, 0.2));
  box-shadow: inset 0 0 0 1px rgba(255, 255, 255, 0.06);
}

.nav-list__link::before {
  content: "";
  width: 8px;
  height: 8px;
  border-radius: 50%;
  background: currentColor;
  opacity: 0.4;
  flex-shrink: 0;
  transition: opacity 0.2s ease, transform 0.2s ease, background 0.2s ease, box-shadow 0.2s ease;
}

.nav-list__link:hover::before {
  opacity: 0.8;
}

.nav-list__link[aria-current="page"]::before {
  opacity: 1;
  transform: scale(1.5);
  background: var(--spring);
  box-shadow: 0 0 12px var(--spring);
}

.nav-toggle {
  display: none;
  width: 44px;
  height: 44px;
  border-radius: 14px;
  background: rgba(255, 255, 255, 0.06);
  border: 1px solid rgba(255, 255, 255, 0.1);
  cursor: pointer;
  padding: 0;
  align-items: center;
  justify-content: center;
  flex-direction: column;
  gap: 5px;
  transition: background 0.2s ease, border-color 0.2s ease;
}

.nav-toggle:hover {
  background: rgba(255, 255, 255, 0.1);
}

.nav-toggle__line {
  display: block;
  width: 18px;
  height: 2px;
  background: var(--winter);
  border-radius: 2px;
  transition: transform 0.3s ease, opacity 0.3s ease;
  transform-origin: center;
}

.nav-toggle[aria-expanded="true"] .nav-toggle__line:nth-child(1) {
  transform: translateY(7px) rotate(45deg);
}

.nav-toggle[aria-expanded="true"] .nav-toggle__line:nth-child(2) {
  opacity: 0;
}

.nav-toggle[aria-expanded="true"] .nav-toggle__line:nth-child(3) {
  transform: translateY(-7px) rotate(-45deg);
}

.season-status {
  margin-top: auto;
  padding: 14px 16px;
  background: rgba(255, 255, 255, 0.04);
  border-radius: var(--radius-lg);
  display: flex;
  align-items: center;
  gap: 12px;
  border: 1px solid rgba(255, 255, 255, 0.04);
}

.season-status__dot {
  width: 10px;
  height: 10px;
  border-radius: 50%;
  background: var(--spring);
  box-shadow: 0 0 12px var(--spring);
  flex-shrink: 0;
}

.season-status__label {
  font-size: 13px;
  font-weight: 500;
  color: #CBD5E1;
  letter-spacing: 0.02em;
}

html[data-season="spring"] .season-status__dot {
  background: var(--spring);
  box-shadow: 0 0 12px var(--spring);
}

html[data-season="summer"] .season-status__dot {
  background: var(--summer);
  box-shadow: 0 0 12px var(--summer);
}

html[data-season="autumn"] .season-status__dot {
  background: var(--autumn);
  box-shadow: 0 0 12px var(--autumn);
}

html[data-season="winter"] .season-status__dot {
  background: #E2E8F0;
  box-shadow: 0 0 12px rgba(255, 255, 255, 0.4);
}

.site-footer {
  position: relative;
  background: var(--night-deep);
  color: #94A3B8;
  padding: 64px 0 32px;
  margin-left: var(--header-w);
  overflow: hidden;
}

.site-footer::before {
  content: "";
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  height: 1px;
  background: linear-gradient(90deg, var(--spring), var(--summer), var(--autumn), transparent);
}

.footer__inner {
  max-width: 1200px;
  margin: 0 auto;
  padding: 0 32px;
  display: grid;
  grid-template-columns: 2fr 1fr 1fr;
  gap: 48px;
  position: relative;
  z-index: 1;
}

.footer__brand {
  display: flex;
  flex-direction: column;
  gap: 16px;
  align-items: flex-start;
}

.footer__trust {
  font-size: 14px;
  line-height: 1.8;
  color: #64748B;
  max-width: 360px;
  margin-top: 8px;
}

.footer__heading {
  font-size: 14px;
  font-weight: 700;
  color: var(--winter);
  letter-spacing: 0.1em;
  text-transform: uppercase;
  margin-bottom: 16px;
}

.footer__list {
  display: flex;
  flex-direction: column;
  gap: 10px;
  font-size: 14px;
}

.footer__list a {
  color: #94A3B8;
  transition: color 0.2s ease, padding-left 0.2s ease;
}

.footer__list a:hover {
  color: var(--spring);
  padding-left: 4px;
}

.footer__meta {
  max-width: 1200px;
  margin: 48px auto 0;
  padding: 24px 32px 0;
  border-top: 1px solid rgba(255, 255, 255, 0.06);
  display: flex;
  justify-content: space-between;
  align-items: center;
  font-size: 13px;
  color: #64748B;
  font-family: var(--font-mono);
  position: relative;
  z-index: 1;
}

.footer-watermark {
  position: absolute;
  right: -60px;
  bottom: -120px;
  font-size: 360px;
  font-weight: 900;
  line-height: 1;
  color: rgba(255, 255, 255, 0.02);
  pointer-events: none;
  user-select: none;
  font-family: var(--font-sans);
}

@media (max-width: 1023px) {
  .site-header {
    bottom: auto;
    width: 100%;
    height: var(--nav-h);
    padding: 0 16px;
    flex-direction: row;
    align-items: center;
    border-right: none;
    border-bottom: 1px solid rgba(255, 255, 255, 0.06);
  }

  .brand__name {
    font-size: 16px;
  }

  .brand__desc {
    display: none;
  }

  .site-nav {
    position: fixed;
    top: var(--nav-h);
    right: 0;
    bottom: 0;
    width: min(320px, 80vw);
    background: var(--night-deep);
    margin-top: 0;
    padding: 24px;
    transform: translateX(100%);
    transition: transform 0.4s cubic-bezier(0.4, 0, 0.2, 1);
    box-shadow: var(--shadow-xl);
    overflow-y: auto;
  }

  .site-nav[data-open] {
    transform: translateX(0);
  }

  .nav-toggle {
    display: flex;
    margin-left: auto;
  }

  .season-status {
    display: none;
  }

  .site-footer {
    margin-left: 0;
    padding: 48px 0 24px;
  }

  .footer__inner {
    grid-template-columns: 1fr;
    gap: 32px;
  }

  .footer__meta {
    flex-direction: column;
    gap: 8px;
    align-items: flex-start;
    margin-top: 32px;
  }
}

@media (max-width: 640px) {
  .footer__inner {
    padding: 0 20px;
  }

  .footer__meta {
    padding-left: 20px;
    padding-right: 20px;
  }

  .footer-watermark {
    font-size: 220px;
    right: -40px;
    bottom: -80px;
  }
}

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

  *,
  *::before,
  *::after {
    animation-duration: 0.01ms !important;
    animation-iteration-count: 1 !important;
    transition-duration: 0.01ms !important;
    transition-delay: 0ms !important;
  }
}