/* ===== Reset & Base ===== */
*, *::before, *::after { box-sizing: border-box; margin: 0; padding: 0; }
html { scroll-behavior: smooth; -webkit-text-size-adjust: 100%; }
body { font-family: 'Inter', system-ui, -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, sans-serif; font-weight: 400; line-height: 1.6; color: #1A1A1A; background-color: #FFFFFF; -webkit-font-smoothing: antialiased; }
img { max-width: 100%; height: auto; display: block; }
a { color: inherit; text-decoration: none; }
ul, ol { list-style: none; }
h1, h2, h3, h4, h5, h6 { font-weight: 800; text-transform: uppercase; letter-spacing: 1px; line-height: 1.2; }
h1 { font-size: 48px; } h2 { font-size: 32px; } h3 { font-size: 24px; } p { font-size: 16px; } small, .caption { font-size: 14px; color: #555555; }
:focus-visible { outline: 3px solid #FF6600; outline-offset: 2px; border-radius: 0; }
@media (prefers-reduced-motion: reduce) { *, *::before, *::after { animation-duration: 0.01ms !important; transition-duration: 0.01ms !important; scroll-behavior: auto !important; } }

/* ===== CSS Variables ===== */
:root {
  --color-primary: #003366;
  --color-primary-dark: #002244;
  --color-accent: #FF6600;
  --color-accent-hover: #E55A00;
  --color-highlight: #FFD700;
  --color-bg: #FFFFFF;
  --color-bg-alt: #F2F2F2;
  --color-text: #1A1A1A;
  --color-text-secondary: #555555;
  --color-border: #CCCCCC;
  --color-success: #28A745;
  --color-error: #DC3545;
  --font-heading: 'Inter', system-ui, -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, sans-serif;
  --font-body: 'Inter', system-ui, -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, sans-serif;
  --max-width: 1200px;
  --header-height: 72px;
  --transition-speed: 300ms;
  --border-radius: 0;
  --border-width: 1px;
}

/* ===== Skip Link ===== */
.skip-link {
  position: absolute; top: -100%; left: 0; z-index: 10000;
  padding: 12px 24px; background-color: var(--color-primary); color: #FFFFFF;
  font-weight: 700; font-size: 16px; transition: top 0.2s;
}
.skip-link:focus { top: 0; outline: 3px solid var(--color-highlight); outline-offset: -3px; }

/* ===== Header ===== */
.site-header {
  position: relative; z-index: 1000;
  background-color: var(--color-primary);
  border-bottom: 2px solid var(--color-highlight);
}
.header-inner {
  max-width: var(--max-width); margin: 0 auto;
  display: flex; align-items: center; justify-content: space-between;
  padding: 0 24px; height: var(--header-height);
}
.header-brand { flex-shrink: 0; }
.header-logo { display: flex; align-items: baseline; gap: 2px; font-weight: 800; font-size: 22px; letter-spacing: 1px; }
.header-logo .logo-mark { color: var(--color-highlight); }
.header-logo .logo-sport { color: #FFFFFF; }
.nav-toggle { display: none; background: none; border: none; cursor: pointer; padding: 8px; align-items: center; gap: 8px; color: #FFFFFF; font-size: 14px; font-weight: 600; }
.nav-toggle-icon { display: block; width: 24px; height: 2px; background-color: #FFFFFF; position: relative; transition: background-color 0.3s; }
.nav-toggle-icon::before, .nav-toggle-icon::after { content: ''; display: block; width: 24px; height: 2px; background-color: #FFFFFF; position: absolute; left: 0; transition: transform 0.3s, top 0.3s; }
.nav-toggle-icon::before { top: -8px; }
.nav-toggle-icon::after { top: 8px; }
.nav-toggle-text { display: none; }
@media (max-width: 767px) {
  .nav-toggle { display: flex; }
  .nav-toggle-text { display: inline; }
  .header-nav { position: absolute; top: var(--header-height); left: 0; right: 0; background-color: var(--color-primary-dark); max-height: 0; overflow: hidden; transition: max-height 0.4s ease-in-out, padding 0.3s; padding: 0 24px; border-bottom: 2px solid transparent; }
  .header-nav[data-open] { max-height: 420px; padding: 16px 24px 20px; border-bottom-color: var(--color-highlight); }
  .nav-list { flex-direction: column; gap: 4px; }
  .nav-item { width: 100%; }
  .nav-link { display: block; padding: 12px 16px; font-size: 16px; border-left: 3px solid transparent; }
  .nav-link[aria-current="page"] { border-left-color: var(--color-accent); background-color: rgba(255,255,255,0.06); }
  .nav-toggle[aria-expanded="true"] .nav-toggle-icon { background-color: transparent; }
  .nav-toggle[aria-expanded="true"] .nav-toggle-icon::before { top: 0; transform: rotate(45deg); }
  .nav-toggle[aria-expanded="true"] .nav-toggle-icon::after { top: 0; transform: rotate(-45deg); }
}
.header-nav { display: flex; align-items: center; }
.nav-list { display: flex; align-items: center; gap: 2px; }
.nav-link {
  display: inline-block; padding: 8px 16px; font-size: 14px; font-weight: 600; letter-spacing: 0.5px;
  color: rgba(255,255,255,0.85); text-transform: uppercase; transition: color 0.25s, background-color 0.25s;
  border-bottom: 2px solid transparent; position: relative;
}
.nav-link:hover, .nav-link:focus-visible { color: var(--color-accent); background-color: rgba(255,255,255,0.05); }
.nav-link[aria-current="page"] { color: var(--color-accent); border-bottom-color: var(--color-accent); }
@media (min-width: 768px) {
  .nav-link { padding: 12px 16px; }
  .header-nav[data-open] { display: flex; }
}
.header-progress {
  position: absolute; bottom: -2px; left: 0; height: 2px; background-color: var(--color-accent);
  width: 0%; transition: width 0.1s linear; z-index: 1001;
}

/* ===== Footer ===== */
.site-footer {
  background-color: var(--color-primary); color: rgba(255,255,255,0.9);
  border-top: 2px solid var(--color-highlight); position: relative;
}
.footer-accent-line { height: 3px; background: linear-gradient(90deg, var(--color-highlight), var(--color-accent), var(--color-highlight)); }
.footer-inner { max-width: var(--max-width); margin: 0 auto; padding: 48px 24px 24px; }
.footer-grid { display: grid; grid-template-columns: 2fr 1fr 1.5fr; gap: 40px; margin-bottom: 32px; }
@media (max-width: 900px) { .footer-grid { grid-template-columns: 1fr 1fr; gap: 32px; } }
@media (max-width: 600px) { .footer-grid { grid-template-columns: 1fr; gap: 28px; } }
.footer-logo { display: inline-flex; align-items: baseline; gap: 2px; font-weight: 800; font-size: 20px; letter-spacing: 1px; margin-bottom: 12px; }
.footer-logo .logo-mark { color: var(--color-highlight); }
.footer-logo .logo-sport { color: #FFFFFF; }
.footer-tagline { font-size: 14px; color: rgba(255,255,255,0.7); margin-bottom: 12px; line-height: 1.5; }
.footer-trust { font-size: 13px; color: rgba(255,255,255,0.55); line-height: 1.6; max-width: 400px; }
.footer-heading { font-size: 14px; color: var(--color-highlight); font-weight: 700; letter-spacing: 1px; margin-bottom: 16px; text-transform: uppercase; border-bottom: 1px solid rgba(255,215,0,0.25); padding-bottom: 8px; }
.footer-nav-list { display: flex; flex-direction: column; gap: 10px; }
.footer-link { color: rgba(255,255,255,0.75); font-size: 14px; transition: color 0.25s, padding-left 0.25s; display: inline-block; }
.footer-link:hover, .footer-link:focus-visible { color: var(--color-accent); padding-left: 4px; }
.footer-contact-item { font-size: 14px; color: rgba(255,255,255,0.75); margin-bottom: 8px; line-height: 1.5; }
.footer-contact-note { font-size: 13px; color: rgba(255,255,255,0.5); margin-top: 12px; font-style: italic; }
.footer-legal { border-top: 1px solid rgba(255,255,255,0.12); padding-top: 20px; margin-top: 8px; }
.footer-icp { display: flex; flex-wrap: wrap; align-items: center; gap: 8px; font-size: 13px; color: rgba(255,255,255,0.5); }
.footer-divider { color: rgba(255,255,255,0.2); }
@media (max-width: 600px) { .footer-legal { text-align: center; } .footer-icp { justify-content: center; } }

/* ===== Container ===== */
.container { max-width: var(--max-width); margin: 0 auto; padding: 0 24px; }

/* ===== Buttons ===== */
.btn { display: inline-flex; align-items: center; justify-content: center; gap: 8px; padding: 12px 28px; font-family: var(--font-body); font-size: 14px; font-weight: 700; text-transform: uppercase; letter-spacing: 1px; border: none; cursor: pointer; transition: background-color 0.3s, transform 0.2s, box-shadow 0.3s; border-radius: var(--border-radius); line-height: 1.2; }
.btn:hover { transform: translateY(-1px); box-shadow: 0 4px 12px rgba(0,0,0,0.15); }
.btn:active { transform: translateY(0); }
.btn-primary { background-color: var(--color-primary); color: #FFFFFF; }
.btn-primary:hover { background-color: var(--color-primary-dark); }
.btn-accent { background-color: var(--color-accent); color: #FFFFFF; }
.btn-accent:hover { background-color: var(--color-accent-hover); }
.btn-outline { background-color: transparent; border: 2px solid var(--color-primary); color: var(--color-primary); }
.btn-outline:hover { background-color: var(--color-primary); color: #FFFFFF; }
.btn-disabled { opacity: 0.5; cursor: not-allowed; pointer-events: none; }
.btn-sm { padding: 8px 18px; font-size: 12px; }

/* ===== Breadcrumb ===== */
.breadcrumb { display: flex; flex-wrap: wrap; align-items: center; gap: 6px; padding: 16px 0; font-size: 13px; color: var(--color-text-secondary); }
.breadcrumb a { color: var(--color-primary); transition: color 0.2s; }
.breadcrumb a:hover { color: var(--color-accent); }
.breadcrumb [aria-current="page"] { color: var(--color-text); font-weight: 600; }
.breadcrumb-sep { color: var(--color-border); margin: 0 2px; }

/* ===== Content Container ===== */
.content { max-width: 720px; margin: 0 auto; padding: 0 24px; }
.content p { margin-bottom: 1.2em; color: var(--color-text); }
.content h2 { margin-top: 2em; margin-bottom: 0.5em; }
.content h3 { margin-top: 1.5em; margin-bottom: 0.4em; }

/* ===== Grid ===== */
.grid { display: grid; gap: 24px; }
.grid-2 { grid-template-columns: repeat(2, 1fr); }
.grid-3 { grid-template-columns: repeat(3, 1fr); }
.grid-4 { grid-template-columns: repeat(4, 1fr); }
@media (max-width: 900px) { .grid-3, .grid-4 { grid-template-columns: repeat(2, 1fr); } }
@media (max-width: 600px) { .grid-2, .grid-3, .grid-4 { grid-template-columns: 1fr; } }

/* ===== Card ===== */
.card { background-color: var(--color-bg); border: var(--border-width) solid var(--color-border); border-radius: var(--border-radius); padding: 24px; transition: transform 0.3s, box-shadow 0.3s; }
.card:hover { transform: translateY(-3px); box-shadow: 0 8px 24px rgba(0,0,0,0.08); }
.card-title { font-size: 18px; font-weight: 700; margin-bottom: 8px; color: var(--color-primary); }
.card-body { font-size: 14px; color: var(--color-text-secondary); line-height: 1.6; }
.card-group { display: grid; gap: 20px; }

/* ===== Folder (档案夹) ===== */
.folder { background-color: var(--color-bg); border: var(--border-width) solid var(--color-border); border-radius: var(--border-radius); overflow: hidden; }
.folder-tab { background-color: var(--color-primary); color: #FFFFFF; padding: 8px 20px; font-size: 12px; font-weight: 700; text-transform: uppercase; letter-spacing: 1px; display: inline-block; border-bottom: 2px solid var(--color-highlight); }
.folder-body { padding: 20px 24px; }

/* ===== Tag ===== */
.tag { display: inline-flex; align-items: center; padding: 4px 12px; font-size: 12px; font-weight: 600; text-transform: uppercase; letter-spacing: 0.5px; border-radius: var(--border-radius); line-height: 1.4; }
.tag-accent { background-color: var(--color-accent); color: #FFFFFF; }
.tag-primary { background-color: var(--color-primary); color: #FFFFFF; }
.tag-outline { background-color: transparent; border: 1px solid var(--color-border); color: var(--color-text-secondary); }
.tag-dismiss { margin-left: 6px; cursor: pointer; opacity: 0.7; transition: opacity 0.2s; }
.tag-dismiss:hover { opacity: 1; }
.tag-group { display: flex; flex-wrap: wrap; gap: 8px; }

/* ===== Section Number ===== */
.section-number { display: flex; align-items: baseline; gap: 16px; margin-bottom: 24px; }
.section-number .num { font-size: 56px; font-weight: 800; color: var(--color-primary); line-height: 1; letter-spacing: -2px; }
.section-number .num-accent { color: var(--color-accent); }
.section-number .label { font-size: 14px; font-weight: 700; text-transform: uppercase; letter-spacing: 2px; color: var(--color-text-secondary); border-bottom: 2px solid var(--color-border); padding-bottom: 4px; }

/* ===== Data Row ===== */
.data-row { display: flex; justify-content: space-between; align-items: center; padding: 10px 0; border-bottom: 1px solid var(--color-border); font-size: 14px; }
.data-row:last-child { border-bottom: none; }
.data-row .label { color: var(--color-text-secondary); font-weight: 500; }
.data-row .value { font-weight: 700; color: var(--color-primary); }
.data-row .value-accent { color: var(--color-accent); }
.data-row .value-gold { color: var(--color-highlight); }

/* ===== Progress Bar ===== */
.progress-bar { width: 100%; }
.progress-track { background-color: var(--color-bg-alt); height: 8px; border-radius: var(--border-radius); overflow: hidden; border: 1px solid var(--color-border); }
.progress-fill { height: 100%; background-color: var(--color-accent); transition: width 0.6s ease; border-radius: var(--border-radius); }
.progress-fill.primary { background-color: var(--color-primary); }
.progress-fill.gold { background-color: var(--color-highlight); }
.progress-label { display: flex; justify-content: space-between; font-size: 12px; color: var(--color-text-secondary); margin-top: 4px; }

/* ===== Stat Card ===== */
.stat-card { text-align: center; padding: 20px; background-color: var(--color-bg); border: var(--border-width) solid var(--color-border); border-radius: var(--border-radius); }
.stat-card .stat-value { font-size: 36px; font-weight: 800; color: var(--color-primary); line-height: 1.2; }
.stat-card .stat-value.accent { color: var(--color-accent); }
.stat-card .stat-value.gold { color: var(--color-highlight); }
.stat-card .stat-label { font-size: 12px; font-weight: 600; text-transform: uppercase; letter-spacing: 1px; color: var(--color-text-secondary); margin-top: 4px; }

/* ===== Image Frame ===== */
.img-frame { position: relative; overflow: hidden; background-color: var(--color-bg-alt); border: var(--border-width) solid var(--color-border); border-radius: var(--border-radius); }
.img-frame img { width: 100%; height: 100%; object-fit: cover; }
.img-frame .img-contain { object-fit: contain; }
.img-frame .img-placeholder { display: flex; align-items: center; justify-content: center; min-height: 180px; color: var(--color-text-secondary); font-size: 14px; }

/* ===== Grid Background Texture ===== */
.grid-bg { background-image: linear-gradient(rgba(0,51,102,0.04) 1px, transparent 1px), linear-gradient(90deg, rgba(0,51,102,0.04) 1px, transparent 1px); background-size: 24px 24px; }
.grid-bg-dark { background-image: linear-gradient(rgba(255,255,255,0.06) 1px, transparent 1px), linear-gradient(90deg, rgba(255,255,255,0.06) 1px, transparent 1px); background-size: 24px 24px; }

/* ===== Utility ===== */
.text-center { text-align: center; }
.text-accent { color: var(--color-accent); }
.text-gold { color: var(--color-highlight); }
.text-primary { color: var(--color-primary); }
.mt-1 { margin-top: 16px; } .mt-2 { margin-top: 32px; } .mt-3 { margin-top: 48px; }
.mb-1 { margin-bottom: 16px; } .mb-2 { margin-bottom: 32px; } .mb-3 { margin-bottom: 48px; }
.py-1 { padding-top: 16px; padding-bottom: 16px; } .py-2 { padding-top: 32px; padding-bottom: 32px; } .py-3 { padding-top: 48px; padding-bottom: 48px; }
.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; }

/* ===== Responsive Helpers ===== */
@media (max-width: 767px) {
  .hide-mobile { display: none !important; }
  h1 { font-size: 32px; } h2 { font-size: 24px; } h3 { font-size: 20px; }
  .section-number .num { font-size: 40px; }
}
@media (min-width: 768px) and (max-width: 1023px) {
  .hide-tablet { display: none !important; }
}
@media (min-width: 1024px) {
  .hide-desktop { display: none !important; }
}