:root {
  --bg: #0b0d10;
  --fg: #eef1f5;
  --muted: #8a93a3;
  --line: rgba(255, 255, 255, 0.12);
  --chip: rgba(16, 19, 24, 0.72);
  --chip-hover: rgba(30, 35, 44, 0.9);
  --open: #5ec8ff;
  --seen: #22346c;
  --path: #ff6b5a;
  --mud: #1c2230;
  --mono: ui-monospace, "SF Mono", "JetBrains Mono", Menlo, Consolas, monospace;
  --sans: ui-sans-serif, -apple-system, "Segoe UI", Roboto, "Helvetica Neue", Arial, sans-serif;
}

* { box-sizing: border-box; }

html, body {
  margin: 0;
  height: 100%;
  background: var(--bg);
  color: var(--fg);
  font-family: var(--sans);
  -webkit-font-smoothing: antialiased;
}

body {
  display: grid;
  grid-template-rows: 1fr auto;
  min-height: 100svh;
  overflow: hidden;
}

#grid {
  position: fixed;
  inset: 0;
  width: 100%;
  height: 100%;
  display: block;
}

/* Keeps the text readable over the animation without boxing it in. */
.veil {
  position: fixed;
  inset: 0;
  pointer-events: none;
  background:
    radial-gradient(ellipse 42rem 22rem at 50% 46%, rgba(11, 13, 16, 0.86), rgba(11, 13, 16, 0.35) 65%, transparent),
    linear-gradient(to top, rgba(11, 13, 16, 0.9), transparent 7rem);
}

main {
  position: relative;
  align-self: center;
  justify-self: center;
  text-align: center;
  padding: 0 16px;
  pointer-events: none;
}

h1 {
  margin: 0;
  font-weight: 600;
  font-size: clamp(2.4rem, 7vw, 4.5rem);
  letter-spacing: -0.02em;
  line-height: 1.05;
}

.role {
  margin: 0.75rem 0 2rem;
  color: var(--muted);
  font-family: var(--mono);
  font-size: 0.9rem;
  letter-spacing: 0.04em;
}

nav {
  display: flex;
  gap: 0.6rem;
  justify-content: center;
  flex-wrap: wrap;
  pointer-events: auto;
}

nav a {
  display: inline-flex;
  align-items: center;
  gap: 0.5rem;
  padding: 0.6rem 1rem;
  border: 1px solid var(--line);
  border-radius: 999px;
  background: var(--chip);
  color: var(--fg);
  text-decoration: none;
  font-size: 0.95rem;
  backdrop-filter: blur(6px);
  transition: background 0.15s, border-color 0.15s, transform 0.15s;
}

nav a:hover { background: var(--chip-hover); border-color: rgba(255, 255, 255, 0.25); transform: translateY(-1px); }
nav a:focus-visible { outline: 2px solid var(--open); outline-offset: 2px; }
nav a.primary { border-color: rgba(255, 107, 90, 0.55); }
nav a.primary:hover { border-color: var(--path); }

nav svg {
  width: 18px;
  height: 18px;
  fill: none;
  stroke: currentColor;
  stroke-width: 1.8;
  stroke-linecap: round;
  stroke-linejoin: round;
}

footer {
  position: relative;
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 0.5rem;
  padding: 0 16px 1.25rem;
  font-family: var(--mono);
  font-size: 0.75rem;
  color: var(--muted);
}

#algo {
  display: inline-flex;
  flex-wrap: wrap;
  justify-content: center;
  gap: 0.25rem 0.75rem;
  padding: 0.35rem 0.8rem;
  border: 1px solid transparent;
  border-radius: 6px;
  background: none;
  color: var(--fg);
  font: inherit;
  letter-spacing: 0.08em;
  text-transform: uppercase;
  cursor: pointer;
}

#algo:hover { border-color: var(--line); }
#algo:focus-visible { outline: 2px solid var(--open); outline-offset: 2px; }
#algo .stats { color: var(--muted); text-transform: none; letter-spacing: 0.02em; }

.legend { display: flex; gap: 1rem; flex-wrap: wrap; justify-content: center; }
.legend span { display: inline-flex; align-items: center; gap: 0.35rem; }
.legend i { width: 9px; height: 9px; border-radius: 2px; display: inline-block; }
.k-open { background: var(--open); }
.k-seen { background: var(--seen); }
.k-path { background: var(--path); }
.k-mud { background: var(--mud); outline: 1px solid rgba(255, 255, 255, 0.18); }

@media (max-width: 480px) {
  .legend { gap: 0.6rem; }
  nav a { padding: 0.55rem 0.85rem; }
}