/* ===== 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', -apple-system, BlinkMacSystemFont, sans-serif;
  font-weight: 400;
  line-height: 1.6;
  color: #FFFFFF;
  background-color: #0D1117;
}
img, svg, video {
  display: block;
  max-width: 100%;
}
a {
  color: inherit;
  text-decoration: none;
}
ul {
  list-style: none;
}
button {
  background: none;
  border: none;
  cursor: pointer;
  font: inherit;
  color: inherit;
}
:focus-visible {
  outline: 2px solid #39FF14;
  outline-offset: 2px;
}
@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-deep-blue: #0A192F;
  --color-primary-metallic-silver: #C0C0C0;
  --color-accent-neon-purple: #B829F0;
  --color-accent-neon-green: #39FF14;
  --color-bg-dark: #0D1117;
  --color-bg-card: #161B22;
  --color-text-high-contrast: #FFFFFF;
  --color-text-medium: #B0B0B0;
  --color-divider: #30363D;
  --color-hover-glow: rgba(184, 41, 240, 0.4);
  --font-heading: 'Inter', sans-serif;
  --font-body: 'Inter', sans-serif;
  --font-data: 'JetBrains Mono', monospace;
  --max-width: 1200px;
  --header-height: 68px;
}

/* ===== Skip Link ===== */
.skip-link {
  position: absolute;
  top: -100%;
  left: 0;
  z-index: 10000;
  padding: 8px 16px;
  background: var(--color-accent-neon-purple);
  color: #fff;
  font-weight: 600;
  transition: top 0.2s;
}
.skip-link:focus {
  top: 0;
}

/* ===== Scroll Progress Bar ===== */
.scroll-progress {
  position: fixed;
  top: 0;
  left: 0;
  z-index: 9999;
  width: 0%;
  height: 3px;
  background: linear-gradient(90deg, var(--color-accent-neon-purple), var(--color-accent-neon-green));
  transition: width 0.1s linear;
  pointer-events: none;
}

/* ===== Header ===== */
.header {
  position: sticky;
  top: 0;
  z-index: 1000;
  background: var(--color-primary-deep-blue);
  border-bottom: 1px solid var(--color-divider);
  height: var(--header-height);
  display: flex;
  align-items: center;
}
.header-inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  width: 100%;
  max-width: var(--max-width);
  margin: 0 auto;
  padding: 0 20px;
  height: 100%;
}
.header__logo {
  font-family: var(--font-heading);
  font-weight: 800;
  font-size: 1.24rem;
  letter-spacing: -0.02em;
  color: var(--color-text-high-contrast);
  white-space: nowrap;
}
.header__nav ul {
  display: flex;
  gap: 28px;
}
.header__nav a {
  font-size: 0.95rem;
  font-weight: 500;
  color: var(--color-text-medium);
  padding: 6px 0;
  position: relative;
  transition: color 0.25s, box-shadow 0.25s;
}
.header__nav a:hover,
.header__nav a:focus-visible {
  color: var(--color-accent-neon-green);
  box-shadow: 0 1px 0 var(--color-accent-neon-green);
}
.header__nav a[aria-current="page"] {
  color: var(--color-accent-neon-purple);
  font-weight: 700;
  box-shadow: 0 2px 0 var(--color-accent-neon-purple);
}
.header__menu-toggle {
  display: none;
  flex-direction: column;
  justify-content: center;
  align-items: center;
  width: 36px;
  height: 36px;
  gap: 5px;
  padding: 4px;
  border: 1px solid var(--color-divider);
  border-radius: 4px;
  transition: border-color 0.25s;
}
.header__menu-toggle:hover {
  border-color: var(--color-accent-neon-purple);
}
.hamburger-line {
  display: block;
  width: 22px;
  height: 2px;
  background: var(--color-text-high-contrast);
  border-radius: 2px;
  transition: transform 0.3s, opacity 0.3s;
}
.header__cta {
  flex-shrink: 0;
}
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  padding: 10px 24px;
  background: var(--color-accent-neon-purple);
  color: #fff;
  font-weight: 700;
  font-size: 0.94rem;
  border-radius: 6px;
  transition: transform 0.2s, box-shadow 0.2s, background 0.2s;
  letter-spacing: 0.02em;
}
.btn:hover,
.btn:focus-visible {
  transform: scale(1.05);
  box-shadow: 0 0 20px var(--color-hover-glow);
  background: #9b20d0;
}
.btn:active {
  transform: scale(0.97);
}

/* ===== Footer ===== */
.footer {
  background: var(--color-primary-deep-blue);
  border-top: 1px solid var(--color-divider);
  padding: 48px 20px 24px;
  color: var(--color-text-medium);
}
.footer-inner {
  max-width: var(--max-width);
  margin: 0 auto;
  display: grid;
  grid-template-columns: 1fr 1fr 1fr;
  gap: 32px;
}
.footer__logo {
  font-family: var(--font-heading);
  font-weight: 800;
  font-size: 1.4rem;
  letter-spacing: -0.02em;
  color: var(--color-text-high-contrast);
  display: block;
  margin-bottom: 8px;
}
.footer__logo-sub {
  font-weight: 400;
  font-size: 0.9rem;
  margin-left: 6px;
  color: var(--color-accent-neon-purple);
}
.footer__copyright {
  font-size: 0.85rem;
  color: var(--color-text-medium);
  margin-top: 8px;
}
.footer__links {
  display: flex;
  flex-direction: column;
  gap: 12px;
}
.footer__links a {
  font-size: 0.95rem;
  color: var(--color-text-medium);
  transition: color 0.2s;
}
.footer__links a:hover,
.footer__links a:focus-visible {
  color: var(--color-accent-neon-green);
}
.footer__contact {
  display: flex;
  flex-direction: column;
  gap: 6px;
  font-size: 0.9rem;
}
.footer__bottom {
  max-width: var(--max-width);
  margin: 24px auto 0;
  padding-top: 20px;
  border-top: 1px solid var(--color-divider);
  text-align: center;
  font-size: 0.8rem;
  color: var(--color-text-medium);
}

/* ===== Common Components ===== */
.container {
  max-width: var(--max-width);
  margin: 0 auto;
  padding: 0 20px;
}
.section {
  padding: 80px 0;
}
.card {
  background: var(--color-bg-card);
  border: 1px solid var(--color-divider);
  border-radius: 12px;
  padding: 24px;
  transition: transform 0.25s, box-shadow 0.25s;
  backdrop-filter: blur(8px);
  background: rgba(22, 27, 34, 0.9);
}
.card:hover {
  transform: translateY(-4px);
  box-shadow: 0 8px 24px rgba(184,41,240,0.25);
}
.data-value {
  font-family: var(--font-data);
  font-weight: 500;
  letter-spacing: -0.01em;
}

/* ===== Grid Utility ===== */
.grid-3 {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 24px;
}
.grid-2 {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 24px;
}

/* ===== Responsive ===== */
@media (max-width: 1024px) {
  .footer-inner {
    grid-template-columns: 1fr 1fr;
    gap: 24px;
  }
}
@media (max-width: 768px) {
  .header__nav {
    position: fixed;
    top: var(--header-height);
    left: 0;
    width: 100%;
    height: calc(100vh - var(--header-height));
    background: var(--color-primary-deep-blue);
    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: center;
    opacity: 0;
    visibility: hidden;
    transition: opacity 0.3s, visibility 0.3s;
    z-index: 999;
  }
  [data-open] .header__nav {
    opacity: 1;
    visibility: visible;
  }
  [data-open] .header__nav ul {
    flex-direction: column;
    gap: 32px;
  }
  [data-open] .header__nav a {
    font-size: 1.2rem;
  }
  .header__menu-toggle {
    display: flex;
  }
  [data-open] .hamburger-line:nth-child(1) {
    transform: translateY(7px) rotate(45deg);
  }
  [data-open] .hamburger-line:nth-child(2) {
    opacity: 0;
  }
  [data-open] .hamburger-line:nth-child(3) {
    transform: translateY(-7px) rotate(-45deg);
  }
  .header__cta {
    display: none;
  }
  .footer-inner {
    grid-template-columns: 1fr;
    text-align: center;
    gap: 24px;
  }
  .grid-3, .grid-2 {
    grid-template-columns: 1fr;
  }
}
@media (max-width: 480px) {
  .header__logo {
    font-size: 1.1rem;
  }
  .section {
    padding: 48px 0;
  }
}

/* ===== Data Year Placeholder ===== */
[data-year]::after {
  content: attr(data-year);
}

/* ===== Decorative Grid Lines (for future arena feel) ===== */
.header::after {
  content: '';
  position: absolute;
  bottom: -1px;
  left: 0;
  width: 100%;
  height: 2px;
  background: linear-gradient(90deg, transparent 0%, var(--color-accent-neon-purple) 20%, var(--color-accent-neon-green) 80%, transparent 100%);
  opacity: 0.6;
}