*,
*::before,
*::after {
  box-sizing: border-box;
}

html {
  color-scheme: dark;
}

body {
  margin: 0;
  min-height: 100vh;
  display: flex;
  flex-direction: column;
  font-family: "Segoe UI", system-ui, -apple-system, sans-serif;
  font-size: 1rem;
  line-height: 1.6;
  color: #d8e8dc;
  background:
    radial-gradient(circle at 20% 10%, rgba(62, 207, 122, 0.12), transparent 40%),
    radial-gradient(circle at 80% 90%, rgba(36, 150, 82, 0.1), transparent 35%),
    linear-gradient(160deg, #0a120e 0%, #101a14 45%, #0d1510 100%);
}

.wrap {
  width: min(920px, calc(100% - 2rem));
  margin: 0 auto;
}

.site-header {
  border-bottom: 1px solid rgba(62, 207, 122, 0.18);
  background: rgba(8, 14, 10, 0.85);
  backdrop-filter: blur(8px);
}

.site-header .wrap {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 1rem;
  padding: 1rem 0;
}

.logo {
  font-weight: 700;
  font-size: 1.15rem;
  letter-spacing: 0.04em;
  text-decoration: none;
  color: #7ef0a8;
}

.site-nav {
  display: flex;
  gap: 1.25rem;
}

.site-nav a {
  text-decoration: none;
  color: #9bb8a6;
  font-size: 0.95rem;
  transition: color 0.15s ease;
}

.site-nav a:hover,
.site-nav a.active {
  color: #d8ffe6;
}

main {
  flex: 1;
  padding: 2rem 0 3rem;
}

.hero {
  margin-bottom: 2rem;
}

.hero h1 {
  margin: 0 0 0.75rem;
  font-size: clamp(1.8rem, 4vw, 2.6rem);
  line-height: 1.15;
  color: #f0fff4;
}

.lead {
  margin: 0;
  max-width: 52ch;
  color: #a8c4b4;
  font-size: 1.05rem;
}

.game-panel {
  padding: 1.5rem;
  border: 1px solid rgba(62, 207, 122, 0.22);
  border-radius: 16px;
  background: rgba(12, 22, 16, 0.72);
  box-shadow: 0 18px 48px rgba(0, 0, 0, 0.35);
}

.hud {
  display: flex;
  flex-wrap: wrap;
  gap: 1rem 1.5rem;
  margin-bottom: 1rem;
  font-size: 0.95rem;
  color: #9bb8a6;
}

.hud strong {
  color: #f0fff4;
  font-variant-numeric: tabular-nums;
}

.hud-status {
  margin-left: auto;
  color: #7ef0a8;
}

#board {
  display: block;
  width: min(400px, 100%);
  height: auto;
  margin: 0 auto;
  border-radius: 8px;
  border: 2px solid rgba(62, 207, 122, 0.35);
  background: #081008;
  image-rendering: pixelated;
  touch-action: none;
}

.hint {
  margin: 1rem 0 0;
  text-align: center;
  font-size: 0.9rem;
  color: #7a9686;
}

.page-content h1 {
  margin: 0 0 1rem;
  font-size: clamp(1.6rem, 3vw, 2.2rem);
  color: #f0fff4;
}

.page-content h2 {
  margin: 2rem 0 0.75rem;
  font-size: 1.2rem;
  color: #c8ecd6;
}

.page-content p,
.page-content ul {
  max-width: 62ch;
  color: #b0c9b8;
}

.page-content ul {
  padding-left: 1.25rem;
}

.page-content li {
  margin-bottom: 0.35rem;
}

.page-content code {
  padding: 0.1rem 0.35rem;
  border-radius: 4px;
  background: rgba(62, 207, 122, 0.12);
  color: #c8ecd6;
  font-size: 0.92em;
}

.text-link {
  color: #7ef0a8;
  text-decoration: none;
  border-bottom: 1px solid rgba(126, 240, 168, 0.35);
}

.text-link:hover {
  color: #d8ffe6;
  border-bottom-color: rgba(216, 255, 230, 0.6);
}

.error-page {
  text-align: center;
}

.error-code {
  margin: 0;
  font-size: 4rem;
  font-weight: 800;
  line-height: 1;
  color: rgba(62, 207, 122, 0.35);
}

.error-page h1 {
  margin-top: 0.5rem;
}

.error-page p {
  margin-left: auto;
  margin-right: auto;
}

.site-footer {
  border-top: 1px solid rgba(62, 207, 122, 0.12);
  padding: 1.25rem 0 2rem;
  font-size: 0.875rem;
  color: #6d8878;
}

@media (max-width: 560px) {
  .site-header .wrap {
    flex-direction: column;
    align-items: flex-start;
  }

  .hud-status {
    margin-left: 0;
  }

  .game-panel {
    padding: 1rem;
  }
}