@import url('https://fonts.googleapis.com/css2?family=IBM+Plex+Mono:wght@400;500;600&family=Inter:wght@400;500;600&display=swap');

:root {
  --bg: #0a0a0a;
  --surface: #131313;
  --surface-2: #1a1a1a;
  --border: #1f1f1f;
  --border-strong: #2a2a2a;
  --text: #ededed;
  --text-muted: #7a7a7a;
  --accent: #b6f44d;
  --header-h: 64px;

  --mono: 'IBM Plex Mono', ui-monospace, 'SF Mono', Menlo, monospace;
  --sans: 'Inter', system-ui, -apple-system, 'Segoe UI', sans-serif;
}

* { box-sizing: border-box; }

html { background: var(--bg); }

body {
  margin: 0;
  font-family: var(--sans);
  color: var(--text);
  background: var(--bg);
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
}

#body_graph {
  overflow: hidden;
}

/* ---------- Header ---------- */

header {
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  height: var(--header-h);
  z-index: 100;
  background: rgba(10, 10, 10, 0.72);
  backdrop-filter: saturate(140%) blur(12px);
  -webkit-backdrop-filter: saturate(140%) blur(12px);
  border-bottom: 1px solid var(--border);
}

header .container {
  height: 100%;
  width: 100%;
  max-width: 1200px;
  margin: 0 auto;
  padding: 0 24px;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 24px;
}

.logo {
  margin: 0;
  font-family: var(--mono);
  font-weight: 600;
  font-size: 15px;
  letter-spacing: 0.01em;
  color: var(--text);
  white-space: nowrap;
}

.logo sup {
  font-family: var(--sans);
  font-weight: 400;
  font-size: 10px;
  text-transform: uppercase;
  letter-spacing: 0.12em;
  color: var(--text-muted);
  margin-left: 6px;
  vertical-align: middle;
}

nav ul {
  margin: 0;
  padding: 0;
  list-style: none;
  display: flex;
  gap: 28px;
}

nav li { padding: 0; }

nav a {
  font-family: var(--mono);
  font-size: 12px;
  letter-spacing: 0.08em;
  text-transform: uppercase;
  color: var(--text-muted);
  text-decoration: none;
  padding: 6px 2px;
  position: relative;
  transition: color 150ms ease;
}

nav a:hover,
nav a:focus-visible {
  color: var(--text);
  outline: none;
}

nav a[aria-current="page"] {
  color: var(--text);
}

nav a[aria-current="page"]::after {
  content: '';
  position: absolute;
  left: 0;
  right: 0;
  bottom: -2px;
  height: 1px;
  background: var(--accent);
}

/* ---------- Buttons / links ---------- */

a {
  color: var(--text);
  text-decoration: none;
}

button {
  font-family: inherit;
  background: transparent;
  border: 1px solid var(--border-strong);
  color: var(--text);
  cursor: pointer;
  border-radius: 2px;
  transition: border-color 150ms ease, color 150ms ease, background 150ms ease;
}

button:hover {
  border-color: var(--text-muted);
}

button:focus-visible {
  outline: 1px solid var(--accent);
  outline-offset: 2px;
}

/* ---------- About page ---------- */

#about {
  max-width: 680px;
  margin: 0 auto;
  padding: calc(var(--header-h) + 80px) 24px 96px;
  font-family: var(--sans);
  font-size: 16px;
  line-height: 1.7;
  color: var(--text);
}

#about p {
  margin: 0 0 1.1em;
  color: #d4d4d4;
}

#about p:first-of-type {
  font-size: 19px;
  line-height: 1.55;
  color: var(--text);
  margin-bottom: 2.4em;
}

#about h2 {
  font-family: var(--mono);
  font-weight: 500;
  font-size: 11px;
  text-transform: uppercase;
  letter-spacing: 0.22em;
  color: var(--accent);
  margin: 3.2em 0 0.8em;
  padding-bottom: 12px;
  border-bottom: 1px solid var(--border);
}

#about h3 {
  font-family: var(--mono);
  font-weight: 500;
  font-size: 13px;
  letter-spacing: 0.04em;
  color: var(--text);
  text-transform: none;
  margin: 2em 0 0.5em;
}

#about h3::before {
  content: '/ ';
  color: var(--text-muted);
}

#about a {
  color: var(--text);
  border-bottom: 1px solid var(--border-strong);
  transition: border-color 150ms ease, color 150ms ease;
}

#about a:hover {
  color: var(--accent);
  border-bottom-color: var(--accent);
}

#about .byline {
  margin-top: 4em;
  font-family: var(--mono);
  font-size: 12px;
  color: var(--text-muted);
  text-align: left;
  letter-spacing: 0.02em;
}

/* ---------- Responsive ---------- */

@media (max-width: 640px) {
  header .container {
    padding: 0 16px;
    gap: 12px;
  }
  .logo {
    font-size: 13px;
  }
  .logo sup {
    display: none;
  }
  nav ul {
    gap: 18px;
  }
  nav a {
    font-size: 11px;
    letter-spacing: 0.06em;
  }
  #about {
    padding-left: 20px;
    padding-right: 20px;
    padding-top: calc(var(--header-h) + 56px);
    font-size: 15px;
  }
  #about p:first-of-type {
    font-size: 17px;
  }
}