/* === Reset === */
*, *::before, *::after { box-sizing: border-box; margin: 0; padding: 0; }
html { scroll-behavior: smooth; -webkit-text-size-adjust: 100%; }
body { min-height: 100vh; line-height: 1.6; -webkit-font-smoothing: antialiased; }
img, svg { display: block; max-width: 100%; }
ul, ol { list-style: none; }
a { text-decoration: none; color: inherit; }
button { font: inherit; border: none; background: none; cursor: pointer; }
input, textarea { font: inherit; border: none; outline: none; }
h1, h2, h3, h4, h5, h6 { font-weight: normal; }

/* === CSS Variables === */
:root {
  --color-primary: #2E8B57;
  --color-primary-dark: #1E6B3A;
  --color-primary-light: #4CAF6E;
  --color-accent: #DC143C;
  --color-accent-dark: #B01030;
  --color-accent-light: #FF4D6D;
  --color-highlight: #FFD700;
  --color-highlight-dark: #D4B000;
  --color-bg-light: #F0F8F0;
  --color-bg-dark: #1A2E1A;
  --color-bg-dark-light: #2A4A2A;
  --color-text: #222222;
  --color-text-secondary: #555555;
  --color-text-light: #FFFFFF;
  --color-border: #CCCCCC;
  --color-border-light: #E0E0E0;
  --color-white: #FFFFFF;
  --color-black: #111111;
  --font-heading: 'Oswald', 'Impact', 'Arial Black', sans-serif;
  --font-body: 'Noto Sans SC', 'PingFang SC', 'Microsoft YaHei', 'Hiragino Sans GB', sans-serif;
  --font-number: 'Fira Code', 'Consolas', 'Monaco', 'Courier New', monospace;
  --font-scale-h1: 48px;
  --font-scale-h2: 32px;
  --font-scale-h3: 24px;
  --font-scale-body: 16px;
  --font-scale-small: 14px;
  --spacing-xs: 4px;
  --spacing-sm: 8px;
  --spacing-md: 16px;
  --spacing-lg: 24px;
  --spacing-xl: 32px;
  --spacing-2xl: 48px;
  --spacing-3xl: 64px;
  --max-width: 1280px;
  --max-width-content: 1200px;
  --max-width-narrow: 800px;
  --radius-sm: 4px;
  --radius-md: 8px;
  --radius-lg: 12px;
  --radius-xl: 20px;
  --radius-round: 50%;
  --transition-fast: 0.15s ease;
  --transition-base: 0.25s ease;
  --transition-slow: 0.4s ease;
  --shadow-sm: 0 1px 3px rgba(0,0,0,0.08);
  --shadow-md: 0 4px 12px rgba(0,0,0,0.1);
  --shadow-lg: 0 8px 24px rgba(0,0,0,0.12);
  --header-height: 64px;
  --progress-height: 3px;
}
@media (prefers-reduced-motion: reduce) {
  :root { --transition-fast: 0s; --transition-base: 0s; --transition-slow: 0s; }
  html { scroll-behavior: auto; }
}

/* === Typography === */
body { font-family: var(--font-body); font-size: var(--font-scale-body); color: var(--color-text); line-height: 1.7; background: var(--color-white); }
h1, h2, h3, h4, h5, h6 { font-family: var(--font-heading); line-height: 1.2; color: var(--color-text); }
h1 { font-size: var(--font-scale-h1); font-weight: 700; letter-spacing: 0.5px; }
h2 { font-size: var(--font-scale-h2); font-weight: 700; letter-spacing: 0.3px; }
h3 { font-size: var(--font-scale-h3); font-weight: 700; letter-spacing: 0.2px; }
p { margin-bottom: var(--spacing-md); }
small { font-size: var(--font-scale-small); }

/* === Skip Link === */
.skip-link { position: absolute; top: -100%; left: var(--spacing-md); padding: var(--spacing-sm) var(--spacing-md); background: var(--color-primary); color: var(--color-white); font-size: var(--font-scale-small); border-radius: var(--radius-sm); z-index: 10000; transition: top var(--transition-base); }
.skip-link:focus { top: var(--spacing-sm); }

/* === Progress Track === */
.progress-track { position: fixed; top: 0; left: 0; width: 100%; height: var(--progress-height); background: var(--color-border-light); z-index: 9999; }
.progress-bar { height: 100%; width: 0%; background: linear-gradient(90deg, var(--color-primary), var(--color-accent)); transition: width 0.1s linear; transform-origin: left; }
@media (prefers-reduced-motion: reduce) { .progress-bar { transition: none; } }

/* === Site Header === */
.site-header { position: sticky; top: var(--progress-height); background: var(--color-white); border-bottom: 1px solid var(--color-border-light); z-index: 1000; height: var(--header-height); }
.header-inner { max-width: var(--max-width); margin: 0 auto; padding: 0 var(--spacing-lg); height: 100%; display: flex; align-items: center; justify-content: space-between; }
.brand { font-family: var(--font-heading); font-size: 28px; font-weight: 700; color: var(--color-primary); letter-spacing: 1px; transition: color var(--transition-fast); flex-shrink: 0; }
.brand:hover { color: var(--color-primary-dark); }
.brand:focus-visible { outline: 2px solid var(--color-primary); outline-offset: 4px; border-radius: var(--radius-sm); }

/* === Navigation === */
.main-nav { display: flex; align-items: center; gap: var(--spacing-xl); }
.nav-link { font-family: var(--font-heading); font-size: 16px; font-weight: 500; color: var(--color-primary); letter-spacing: 0.5px; text-transform: uppercase; padding: var(--spacing-xs) 0; position: relative; transition: color var(--transition-fast); }
.nav-link:hover { color: var(--color-accent); }
.nav-link:focus-visible { outline: 2px solid var(--color-accent); outline-offset: 4px; border-radius: var(--radius-sm); }
.nav-link[aria-current="page"] { color: var(--color-accent); border-bottom: 2px solid var(--color-accent); }

/* === Nav Toggle (Mobile) === */
.nav-toggle { display: none; flex-direction: column; justify-content: center; align-items: center; width: 40px; height: 40px; gap: 5px; padding: 8px; border-radius: var(--radius-sm); transition: background var(--transition-fast); }
.nav-toggle:hover { background: var(--color-bg-light); }
.nav-toggle:focus-visible { outline: 2px solid var(--color-primary); outline-offset: 2px; }
.nav-toggle-line { display: block; width: 24px; height: 2px; background: var(--color-primary); border-radius: 2px; transition: transform var(--transition-base), opacity var(--transition-base); }
.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); }
@media (prefers-reduced-motion: reduce) { .nav-toggle-line { transition: none; } }

/* === Site Footer === */
.site-footer { background: var(--color-bg-dark); color: var(--color-text-light); padding: var(--spacing-3xl) 0 0; }
.footer-inner { max-width: var(--max-width); margin: 0 auto; padding: 0 var(--spacing-lg); display: grid; grid-template-columns: 2fr 1fr 1.5fr; gap: var(--spacing-2xl); }
.footer-title { font-family: var(--font-heading); font-size: 24px; color: var(--color-highlight); margin-bottom: var(--spacing-md); letter-spacing: 1px; }
.footer-heading { font-family: var(--font-heading); font-size: 18px; color: var(--color-white); margin-bottom: var(--spacing-md); letter-spacing: 0.5px; }
.footer-desc { font-size: var(--font-scale-small); color: rgba(255,255,255,0.7); line-height: 1.8; margin-bottom: 0; }
.footer-link { display: block; font-size: var(--font-scale-small); color: rgba(255,255,255,0.7); padding: var(--spacing-xs) 0; transition: color var(--transition-fast); }
.footer-link:hover { color: var(--color-highlight); }
.footer-link:focus-visible { outline: 2px solid var(--color-highlight); outline-offset: 2px; border-radius: var(--radius-sm); }
.footer-contact-item { font-size: var(--font-scale-small); color: rgba(255,255,255,0.7); margin-bottom: var(--spacing-sm); }
.footer-contact-item .footer-link { display: inline; padding: 0; }
.footer-note { font-size: 13px; color: rgba(255,255,255,0.5); margin-top: var(--spacing-sm); font-style: italic; }
.footer-bottom { margin-top: var(--spacing-2xl); border-top: 1px solid rgba(255,255,255,0.1); padding: var(--spacing-lg) 0; }
.footer-bottom-inner { max-width: var(--max-width); margin: 0 auto; padding: 0 var(--spacing-lg); display: flex; justify-content: space-between; align-items: center; flex-wrap: wrap; gap: var(--spacing-md); }
.footer-copy { font-size: var(--font-scale-small); color: rgba(255,255,255,0.5); margin-bottom: 0; }
.footer-legal { display: flex; align-items: center; gap: var(--spacing-sm); }
.footer-legal-link { font-size: var(--font-scale-small); color: rgba(255,255,255,0.6); transition: color var(--transition-fast); }
.footer-legal-link:hover { color: var(--color-highlight); }
.footer-legal-link:focus-visible { outline: 2px solid var(--color-highlight); outline-offset: 2px; border-radius: var(--radius-sm); }
.footer-legal-sep { color: rgba(255,255,255,0.2); font-size: var(--font-scale-small); }

/* === Container === */
.container { max-width: var(--max-width-content); margin: 0 auto; padding: 0 var(--spacing-lg); }

/* === Sections === */
.section { padding: var(--spacing-3xl) 0; }
.section-wide { width: 100%; }
.section-narrow { max-width: var(--max-width-narrow); margin-left: auto; margin-right: auto; }
.splash-section { min-height: 80vh; display: flex; align-items: center; position: relative; overflow: hidden; }

/* === Buttons === */
.btn { display: inline-flex; align-items: center; justify-content: center; padding: 10px 24px; font-family: var(--font-heading); font-size: 16px; font-weight: 600; letter-spacing: 0.5px; border-radius: var(--radius-md); transition: background var(--transition-fast), transform var(--transition-fast), box-shadow var(--transition-fast); cursor: pointer; text-decoration: none; border: none; }
.btn:hover { transform: translateY(-1px); box-shadow: var(--shadow-md); }
.btn:focus-visible { outline: 2px solid var(--color-accent); outline-offset: 3px; }
.btn:active { transform: translateY(0); }
.btn-primary { background: var(--color-primary); color: var(--color-white); }
.btn-primary:hover { background: var(--color-primary-dark); }
.btn-accent { background: var(--color-accent); color: var(--color-white); }
.btn-accent:hover { background: var(--color-accent-dark); }
.btn-outline { background: transparent; color: var(--color-primary); border: 2px solid var(--color-primary); }
.btn-outline:hover { background: var(--color-primary); color: var(--color-white); }
@media (prefers-reduced-motion: reduce) { .btn { transition: none; } .btn:hover { transform: none; } }

/* === Breadcrumb === */
.breadcrumb { display: flex; align-items: center; flex-wrap: wrap; gap: var(--spacing-sm); font-size: var(--font-scale-small); color: var(--color-text-secondary); padding: var(--spacing-md) 0; }
.breadcrumb a { color: var(--color-primary); transition: color var(--transition-fast); }
.breadcrumb a:hover { color: var(--color-accent); }
.breadcrumb a:focus-visible { outline: 2px solid var(--color-primary); outline-offset: 2px; border-radius: var(--radius-sm); }
.breadcrumb-sep { color: var(--color-border); }
.breadcrumb-current { color: var(--color-text); font-weight: 500; }

/* === Card === */
.card { background: var(--color-bg-light); border-radius: var(--radius-lg); padding: var(--spacing-lg); box-shadow: var(--shadow-sm); transition: box-shadow var(--transition-base), transform var(--transition-base); }
.card:hover { box-shadow: var(--shadow-md); transform: translateY(-2px); }
.card:focus-within { outline: 2px solid var(--color-primary); outline-offset: 2px; }
.card-title { font-family: var(--font-heading); font-size: 20px; margin-bottom: var(--spacing-sm); color: var(--color-text); }
.card-text { font-size: var(--font-scale-small); color: var(--color-text-secondary); line-height: 1.7; }
.card-stat { font-family: var(--font-number); font-size: 36px; color: var(--color-accent); font-weight: 700; }
@media (prefers-reduced-motion: reduce) { .card { transition: none; } .card:hover { transform: none; } }

/* === Tag === */
.tag { display: inline-block; padding: 4px 16px; font-size: var(--font-scale-small); font-weight: 500; color: var(--color-text); background: var(--color-highlight); border-radius: var(--radius-xl); transition: background var(--transition-fast), transform var(--transition-fast); }
.tag:hover { background: var(--color-highlight-dark); transform: scale(1.05); }
.tag:focus-visible { outline: 2px solid var(--color-highlight-dark); outline-offset: 2px; }
.tag-accent { background: var(--color-accent); color: var(--color-white); }
.tag-accent:hover { background: var(--color-accent-dark); }
.tag-outline { background: transparent; border: 1.5px solid var(--color-primary); color: var(--color-primary); }
.tag-outline:hover { background: var(--color-primary); color: var(--color-white); }
@media (prefers-reduced-motion: reduce) { .tag { transition: none; } .tag:hover { transform: none; } }

/* === Label Group === */
.label-group { display: flex; flex-wrap: wrap; gap: var(--spacing-sm); }

/* === Stat Number === */
.stat-number { font-family: var(--font-number); font-size: 40px; font-weight: 700; color: var(--color-accent); line-height: 1; letter-spacing: -0.5px; }
.stat-number-sm { font-size: 28px; }
.stat-number-lg { font-size: 56px; }

/* === Grids === */
.grid-2 { display: grid; grid-template-columns: 1fr 1fr; gap: var(--spacing-lg); }
.grid-3 { display: grid; grid-template-columns: 1fr 1fr 1fr; gap: var(--spacing-lg); }
.grid-4 { display: grid; grid-template-columns: 1fr 1fr 1fr 1fr; gap: var(--spacing-lg); }

/* === Utility === */
.text-center { text-align: center; }
.text-accent { color: var(--color-accent); }
.text-primary { color: var(--color-primary); }
.text-highlight { color: var(--color-highlight); }
.mt-lg { margin-top: var(--spacing-lg); }
.mt-xl { margin-top: var(--spacing-xl); }
.mt-2xl { margin-top: var(--spacing-2xl); }
.mb-lg { margin-bottom: var(--spacing-lg); }
.mb-xl { margin-bottom: var(--spacing-xl); }

/* === Focus Visible Global === */
:focus-visible { outline: 2px solid var(--color-primary); outline-offset: 2px; }
a:focus-visible, button:focus-visible, input:focus-visible, textarea:focus-visible { outline: 2px solid var(--color-accent); outline-offset: 2px; }

/* === Responsive === */
@media (max-width: 1024px) {
  .grid-4 { grid-template-columns: 1fr 1fr; }
  .footer-inner { grid-template-columns: 1fr 1fr; }
  .footer-brand { grid-column: 1 / -1; }
}

@media (max-width: 768px) {
  :root { --header-height: 56px; }
  .header-inner { padding: 0 var(--spacing-md); }
  .nav-toggle { display: flex; }
  .main-nav { position: fixed; top: calc(var(--header-height) + var(--progress-height)); left: 0; width: 100%; background: var(--color-white); flex-direction: column; padding: var(--spacing-md) var(--spacing-lg); gap: 0; border-bottom: 2px solid var(--color-primary); box-shadow: var(--shadow-lg); transform: translateY(-120%); opacity: 0; visibility: hidden; transition: transform var(--transition-base), opacity var(--transition-base), visibility var(--transition-base); z-index: 999; }
  .main-nav[data-open] { transform: translateY(0); opacity: 1; visibility: visible; }
  .nav-link { display: block; padding: var(--spacing-md) 0; border-bottom: 1px solid var(--color-border-light); width: 100%; font-size: 18px; }
  .nav-link[aria-current="page"] { border-bottom-color: var(--color-accent); }
  .nav-link:last-child { border-bottom: none; }
  .grid-2, .grid-3, .grid-4 { grid-template-columns: 1fr; }
  .footer-inner { grid-template-columns: 1fr; gap: var(--spacing-xl); }
  .footer-bottom-inner { flex-direction: column; text-align: center; }
  .footer-legal { justify-content: center; }
  h1 { font-size: 36px; }
  h2 { font-size: 26px; }
  h3 { font-size: 20px; }
  .stat-number { font-size: 32px; }
  .stat-number-lg { font-size: 42px; }
  .section { padding: var(--spacing-2xl) 0; }
  .splash-section { min-height: 60vh; }
  .card { padding: var(--spacing-md); }
}

@media (max-width: 480px) {
  .header-inner { padding: 0 var(--spacing-sm); }
  .brand { font-size: 22px; }
  .container { padding: 0 var(--spacing-md); }
  .stat-number { font-size: 28px; }
  .stat-number-lg { font-size: 36px; }
  h1 { font-size: 30px; }
  h2 { font-size: 22px; }
}

/* === Reduced Motion Overrides === */
@media (prefers-reduced-motion: reduce) {
  .main-nav { transition: none; }
  .skip-link { transition: none; }
  .brand { transition: none; }
  .nav-link { transition: none; }
  .footer-link { transition: none; }
  .footer-legal-link { transition: none; }
  .breadcrumb a { transition: none; }
  .btn { transition: none; }
  .card { transition: none; }
  .tag { transition: none; }
}

/* === Print === */
@media print {
  .site-header { position: static; border-bottom: 1px solid #ccc; }
  .progress-track { display: none; }
  .nav-toggle { display: none; }
  .main-nav { display: flex; gap: 12px; }
  .site-footer { background: #f5f5f5; color: #333; }
  .footer-link { color: #333; }
  .footer-copy { color: #555; }
  .footer-legal-link { color: #333; }
  .footer-heading { color: #333; }
  .footer-title { color: #2E8B57; }
}