/* ============================================================
   godot-go — futuristic dark neon / glass theme
   ============================================================ */

:root {
  --bg: #050510;
  --bg-2: #0a0a18;
  --ink: #e8eaf2;
  --muted: #9aa0b8;
  --cyan: #22d3ee;
  --violet: #8b5cf6;
  --godot: #478cbf;
  --go: #00add8;
  --glass: rgba(255, 255, 255, 0.04);
  --glass-2: rgba(255, 255, 255, 0.06);
  --glass-border: rgba(255, 255, 255, 0.09);
  --font-sans: "Inter", system-ui, -apple-system, sans-serif;
  --font-display: "Space Grotesk", "Inter", system-ui, sans-serif;
  --font-mono: "JetBrains Mono", ui-monospace, "Courier New", monospace;
}

* { box-sizing: border-box; }

html { scroll-behavior: smooth; }

body {
  margin: 0;
  background: radial-gradient(ellipse 120% 80% at 50% -10%, #0c0c22 0%, var(--bg) 55%);
  color: var(--ink);
  font-family: var(--font-sans);
  font-size: 17px;
  line-height: 1.7;
  overflow-x: hidden;
  -webkit-font-smoothing: antialiased;
}

a { color: var(--cyan); text-decoration: none; transition: color 0.2s ease; }
a:hover { color: #7dd3fc; }

code {
  font-family: var(--font-mono);
  font-size: 0.9em;
  background: rgba(34, 211, 238, 0.1);
  color: #a5f3fc;
  padding: 1px 6px;
  border-radius: 5px;
  border: 1px solid rgba(34, 211, 238, 0.18);
}

:focus-visible { outline: 2px solid var(--cyan); outline-offset: 3px; border-radius: 4px; }

/* ---------- Ambient background ---------- */
.bg-grid {
  position: fixed;
  inset: 0;
  z-index: -3;
  background-image:
    linear-gradient(rgba(139, 92, 246, 0.07) 1px, transparent 1px),
    linear-gradient(90deg, rgba(34, 211, 238, 0.07) 1px, transparent 1px);
  background-size: 48px 48px;
  -webkit-mask-image: radial-gradient(ellipse 85% 65% at 50% 0%, #000 35%, transparent 82%);
  mask-image: radial-gradient(ellipse 85% 65% at 50% 0%, #000 35%, transparent 82%);
}

.bg-glow {
  position: fixed;
  border-radius: 50%;
  filter: blur(90px);
  z-index: -2;
  pointer-events: none;
}
.glow-1 {
  width: 520px; height: 520px; top: -140px; left: -90px;
  background: radial-gradient(circle, rgba(34, 211, 238, 0.45), transparent 70%);
  animation: float1 16s ease-in-out infinite;
}
.glow-2 {
  width: 560px; height: 560px; bottom: -180px; right: -110px;
  background: radial-gradient(circle, rgba(139, 92, 246, 0.42), transparent 70%);
  animation: float2 19s ease-in-out infinite;
}
@keyframes float1 {
  0%, 100% { transform: translate(0, 0); }
  50% { transform: translate(40px, 30px); }
}
@keyframes float2 {
  0%, 100% { transform: translate(0, 0); }
  50% { transform: translate(-50px, -30px); }
}

.bg-particles {
  position: fixed;
  inset: 0;
  z-index: -1;
  pointer-events: none;
}

/* ---------- Sticky nav ---------- */
.nav {
  position: sticky;
  top: 0;
  z-index: 50;
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 14px clamp(16px, 5vw, 48px);
  background: rgba(5, 5, 16, 0.6);
  backdrop-filter: blur(14px);
  -webkit-backdrop-filter: blur(14px);
  border-bottom: 1px solid var(--glass-border);
}
.nav-brand {
  display: flex;
  align-items: center;
  gap: 10px;
  font-family: var(--font-display);
  font-weight: 700;
  font-size: 1.15rem;
  color: var(--ink);
}
.nav-brand em { color: var(--cyan); font-style: normal; }
.nav-logo { width: 26px; height: 26px; filter: drop-shadow(0 0 6px rgba(71, 140, 191, 0.6)); }
.nav-links { display: flex; align-items: center; gap: clamp(14px, 2.5vw, 30px); }
.nav-links a { color: var(--muted); font-weight: 500; font-size: 0.95rem; }
.nav-links a:hover { color: var(--ink); }
.nav-cta {
  padding: 8px 16px;
  border: 1px solid var(--glass-border);
  border-radius: 9px;
  background: var(--glass);
  color: var(--ink) !important;
}
.nav-cta:hover { border-color: var(--cyan); box-shadow: 0 0 16px rgba(34, 211, 238, 0.25); }

/* ---------- Hero ---------- */
.hero {
  min-height: 100svh;
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  text-align: center;
  padding: 40px 20px;
  gap: 22px;
}
.logo-lockup {
  display: flex;
  align-items: center;
  gap: 22px;
  margin-bottom: 6px;
}
.logo-godot {
  width: clamp(80px, 12vw, 118px);
  height: auto;
  filter: drop-shadow(0 0 26px rgba(71, 140, 191, 0.6));
}
.logo-go {
  width: clamp(150px, 22vw, 220px);
  height: auto;
  filter: drop-shadow(0 0 22px rgba(0, 173, 216, 0.5));
}
.logo-link {
  width: clamp(28px, 5vw, 64px);
  height: 2px;
  background: linear-gradient(90deg, var(--godot), var(--cyan));
  box-shadow: 0 0 12px var(--cyan);
}
.hero-title {
  font-family: var(--font-display);
  font-weight: 700;
  font-size: clamp(2rem, 6vw, 3.8rem);
  line-height: 1.1;
  margin: 0;
  letter-spacing: -0.02em;
}
.grad {
  background: linear-gradient(120deg, var(--cyan), var(--violet));
  -webkit-background-clip: text;
  background-clip: text;
  color: transparent;
}
.hero-sub {
  max-width: 640px;
  color: var(--muted);
  font-size: clamp(1rem, 2vw, 1.18rem);
  margin: 0;
}
.hero-cta { display: flex; gap: 16px; flex-wrap: wrap; justify-content: center; }
.hero-note { font-size: 0.82rem; color: var(--muted); opacity: 0.8; margin: 0; }

/* ---------- Buttons ---------- */
.btn {
  display: inline-block;
  font-family: var(--font-sans);
  font-weight: 600;
  font-size: 0.98rem;
  padding: 13px 26px;
  border-radius: 11px;
  border: 1px solid transparent;
  cursor: pointer;
  transition: transform 0.15s ease, box-shadow 0.2s ease, border-color 0.2s ease, background 0.2s ease;
}
.btn-primary {
  background: linear-gradient(135deg, var(--cyan), var(--violet));
  color: #050510;
  box-shadow: 0 6px 24px rgba(34, 211, 238, 0.28);
}
.btn-primary:hover { transform: translateY(-2px); box-shadow: 0 10px 32px rgba(139, 92, 246, 0.4); color: #050510; }
.btn-ghost {
  background: var(--glass);
  border-color: var(--glass-border);
  color: var(--ink);
  backdrop-filter: blur(8px);
  -webkit-backdrop-filter: blur(8px);
}
.btn-ghost:hover { transform: translateY(-2px); border-color: var(--cyan); box-shadow: 0 8px 28px rgba(34, 211, 238, 0.2); color: var(--ink); }

/* ---------- Sections ---------- */
.section { max-width: 1080px; margin: 0 auto; padding: 96px 24px; }
.section-title {
  font-family: var(--font-display);
  font-weight: 700;
  font-size: clamp(1.6rem, 4vw, 2.4rem);
  text-align: center;
  margin: 0 0 12px;
  letter-spacing: -0.01em;
}
.section-sub { text-align: center; color: var(--muted); margin: 0 auto 52px; max-width: 620px; }

.reveal { opacity: 0; transform: translateY(28px); transition: opacity 0.7s ease, transform 0.7s ease; }
.reveal.revealed { opacity: 1; transform: none; }

/* ---------- Feature cards ---------- */
.card-grid { display: grid; grid-template-columns: repeat(auto-fit, minmax(280px, 1fr)); gap: 22px; }
.card {
  background: var(--glass);
  border: 1px solid var(--glass-border);
  border-radius: 16px;
  padding: 28px 24px;
  backdrop-filter: blur(12px);
  -webkit-backdrop-filter: blur(12px);
  transition: transform 0.2s ease, border-color 0.2s ease, box-shadow 0.2s ease;
}
.card:hover {
  transform: translateY(-6px);
  border-color: rgba(34, 211, 238, 0.4);
  box-shadow: 0 16px 40px rgba(34, 211, 238, 0.12);
}
.card .icon { width: 40px; height: 40px; color: var(--cyan); margin-bottom: 16px; }
.card:nth-child(even) .icon { color: var(--violet); }
.card h3 { font-family: var(--font-display); font-weight: 600; font-size: 1.15rem; margin: 0 0 10px; }
.card p { margin: 0; color: var(--muted); font-size: 0.96rem; }

/* ---------- Build-dependency OS tabs (Get Started) ---------- */
.os-tabs { display: flex; justify-content: center; gap: 8px; flex-wrap: wrap; margin: 0 auto 30px; }
.os-tab {
  font-family: var(--font-display);
  font-weight: 600;
  font-size: 0.95rem;
  padding: 9px 24px;
  border-radius: 999px;
  border: 1px solid var(--glass-border);
  background: var(--glass);
  color: var(--muted);
  cursor: pointer;
  transition: color 0.2s ease, border-color 0.2s ease, background 0.2s ease, box-shadow 0.2s ease;
}
.os-tab:hover { color: var(--ink); border-color: rgba(34, 211, 238, 0.4); }
.os-tab[aria-selected="true"] {
  color: #050510;
  background: linear-gradient(135deg, var(--cyan), var(--violet));
  border-color: transparent;
  box-shadow: 0 4px 18px rgba(34, 211, 238, 0.3);
}
.os-panel { max-width: 760px; margin: 0 auto 34px; }
.os-panel-head { display: flex; align-items: center; justify-content: center; gap: 12px; margin-bottom: 18px; flex-wrap: wrap; }
.os-panel-head h3 { font-family: var(--font-display); font-weight: 600; font-size: 1.15rem; margin: 0; }
.dep-list {
  list-style: none;
  margin: 0 auto 26px;
  padding: 0;
  max-width: 660px;
  display: flex;
  flex-direction: column;
  gap: 10px;
}
.dep-list li {
  background: var(--glass);
  border: 1px solid var(--glass-border);
  border-radius: 10px;
  padding: 12px 16px;
  color: var(--muted);
  font-size: 0.95rem;
}
.dep-list strong { color: var(--ink); font-weight: 600; }
.tag {
  font-family: var(--font-mono);
  font-size: 0.68rem;
  padding: 2px 9px;
  border-radius: 999px;
  border: 1px solid var(--glass-border);
  color: var(--muted);
  white-space: nowrap;
}
.tag-linux { border-color: rgba(34, 211, 238, 0.45); color: #a5f3fc; }
.tag-windows { border-color: rgba(96, 165, 250, 0.45); color: #bfdbfe; }
.tag-macos { border-color: rgba(226, 232, 240, 0.4); color: #e2e8f0; }
.tag-optional { border-color: rgba(139, 92, 246, 0.55); color: #c4b5fd; }
.tag-note { border-color: rgba(254, 188, 46, 0.5); color: #febc2e; }
.install-note { max-width: 720px; margin: -10px auto 22px; text-align: center; color: var(--muted); font-size: 0.85rem; }

/* ---------- Code blocks ---------- */
.codeblock {
  max-width: 720px;
  margin: 0 auto 22px;
  background: rgba(5, 5, 16, 0.7);
  border: 1px solid var(--glass-border);
  border-radius: 12px;
  overflow: hidden;
  backdrop-filter: blur(10px);
  -webkit-backdrop-filter: blur(10px);
}
.code-head {
  display: flex;
  align-items: center;
  gap: 12px;
  padding: 10px 14px;
  background: var(--glass-2);
  border-bottom: 1px solid var(--glass-border);
}
.dots { display: flex; gap: 6px; }
.dots i { width: 11px; height: 11px; border-radius: 50%; display: block; }
.dots i:nth-child(1) { background: #ff5f57; }
.dots i:nth-child(2) { background: #febc2e; }
.dots i:nth-child(3) { background: #28c840; }
.code-title { font-family: var(--font-mono); font-size: 0.78rem; color: var(--muted); }
.copy-btn {
  margin-left: auto;
  font-family: var(--font-sans);
  font-size: 0.78rem;
  font-weight: 500;
  color: var(--muted);
  background: var(--glass);
  border: 1px solid var(--glass-border);
  border-radius: 7px;
  padding: 5px 12px;
  cursor: pointer;
  transition: color 0.2s ease, border-color 0.2s ease;
}
.copy-btn:hover { color: var(--cyan); border-color: var(--cyan); }
.copy-btn.copied { color: #28c840; border-color: #28c840; }
.codeblock pre {
  margin: 0;
  padding: 18px 18px;
  overflow-x: auto;
  font-family: var(--font-mono);
  font-size: 0.95rem;
  color: #d6f5fb;
}
.codeblock .prompt { color: var(--violet); user-select: none; }

/* ---------- FAQ ---------- */
.faq-list { max-width: 760px; margin: 0 auto; display: flex; flex-direction: column; gap: 14px; }
.faq-item {
  background: var(--glass);
  border: 1px solid var(--glass-border);
  border-radius: 12px;
  backdrop-filter: blur(10px);
  -webkit-backdrop-filter: blur(10px);
  transition: border-color 0.2s ease;
  overflow: hidden;
}
.faq-item:hover { border-color: rgba(139, 92, 246, 0.4); }
.faq-item summary {
  list-style: none;
  cursor: pointer;
  padding: 18px 20px;
  font-family: var(--font-display);
  font-weight: 500;
  font-size: 1.02rem;
  display: flex;
  align-items: center;
  justify-content: space-between;
}
.faq-item summary::-webkit-details-marker { display: none; }
.faq-item summary::after {
  content: "+";
  color: var(--cyan);
  font-size: 1.3rem;
  transition: transform 0.2s ease;
}
.faq-item[open] summary::after { content: "\2212"; }
.faq-answer { padding: 0 20px 18px; color: var(--muted); }
.faq-answer p { margin: 0; }

/* ---------- Footer ---------- */
.footer {
  text-align: center;
  padding: 88px 24px 64px;
  border-top: 1px solid var(--glass-border);
  background: linear-gradient(180deg, transparent, rgba(10, 10, 24, 0.6));
}
.footer-title {
  font-family: var(--font-display);
  font-weight: 700;
  font-size: clamp(1.5rem, 4vw, 2.2rem);
  margin: 0 0 26px;
}
.footer-links { display: flex; gap: 16px; justify-content: center; flex-wrap: wrap; margin-bottom: 22px; }
.footer-hint { color: var(--muted); max-width: 560px; margin: 0 auto 34px; }
.footer-credits { max-width: 640px; margin: 0 auto; }
.footer-credits p { margin: 6px 0; color: var(--muted); font-size: 0.92rem; }
.footer-small { font-size: 0.78rem !important; opacity: 0.7; }

/* ---------- Reduced motion ---------- */
@media (prefers-reduced-motion: reduce) {
  html { scroll-behavior: auto; }
  .bg-glow { animation: none !important; }
  .reveal { opacity: 1 !important; transform: none !important; transition: none !important; }
  .btn, .card, .faq-item, .copy-btn { transition: none !important; }
  .bg-particles { display: none !important; }
}

/* ---------- Small screens ---------- */
@media (max-width: 640px) {
  .nav-links a:not(.nav-cta) { display: none; }
  .logo-lockup { gap: 14px; }
  .section { padding: 72px 18px; }
}