:root {
  --bg:#000000;          /* pure black */
  --fg:#ffffff;          /* white text */
  --muted:#b7b7b7;       /* muted text */
  --accent:#00e0b8;      /* aqua logo color */
  --accent-hover:#1affc9;
  --card:#0f0f0f;        /* card background */
  --line:#222222;        /* border lines */
  --gold: #FFD700;
  --gold-glow: #ffb84d;
}

body {
  margin: 0;
  background: var(--bg);
  color: var(--fg);
  font: 16px/1.6 'Space Grotesk', system-ui, -apple-system, sans-serif;
}

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

.container { max-width: 980px; margin: 0 auto; padding: 24px; }

/* Header */
.header { display: flex; align-items: center; justify-content: space-between; margin-bottom: 12px; }
.logo { height: 210px; }
.header-right { display: flex; gap: 10px; align-items: center; }
.net-tag { font-size: .9rem; color: var(--muted); border: 1px solid var(--line); padding: 6px 10px; border-radius: 8px; }

/* Hero */
.hero { padding: 24px 0; border-bottom: 1px solid var(--line); text-align: center; }
h1 { margin: 0 0 6px 0; font-size: 2.2rem; color: var(--accent); }
.tagline { color: var(--muted); font-size: 1.0rem; }
.prototype-note { font-size: .95rem; color: #ff6666; font-style: italic; margin: 6px 0 12px; }

/* Buttons */
.btn { cursor: pointer; background: #1b1b1b; color: #fff; border: 1px solid var(--line); padding: 10px 14px; border-radius: 10px; transition: all 0.2s ease; }
.btn:hover { background: #222; }
.btn-outline { background: transparent; }
.btn-accent { background: var(--accent); color: #000; border-color: var(--accent); }
.btn-accent:hover { background: var(--accent-hover); }

/* Panels & Cards */
.panel { padding: 24px 0; border-bottom: 1px solid var(--line); }
h2 { color: var(--accent); margin: .2rem 0 1rem; }
.muted { color: var(--muted); margin-top: -4px; }
.grid-2 { display: grid; grid-template-columns: 1fr 1fr; gap: 18px; }
@media (max-width:800px){ .grid-2 { grid-template-columns:1fr; } }

.label { display: block; margin: .75rem 0 .35rem; color: var(--muted); }
.input { width: 100%; padding: 10px 12px; border-radius: 10px; border: 1px solid var(--line); background: #0b0b0b; color: #fff; }

.card { background: var(--card); border: 1px solid var(--line); border-radius: 12px; padding: 14px; }
.card-title { font-weight: 600; margin-bottom: 10px; color: var(--accent); }
.kv { display: flex; justify-content: space-between; border-bottom: 1px dashed var(--line); padding: 6px 0; }
.kv:last-child { border-bottom: 0; }

.toast { margin-top: 10px; padding: 10px 12px; border-left: 4px solid var(--accent); background: #121212; border-radius: 6px; color: #ddd; }

/* --- GFD Unified Footer --- */
.footer {
  background: #000;
  border-top: 1px solid #222;
  text-align: center;
  padding: 40px 0 30px;
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 1.2rem;
}

.footer-logo-wrap {
  display: flex;
  justify-content: center;
  align-items: center;
}

.footer-logo {
  height: 75px;
  filter: brightness(1.2);
}

.footer-slogan {
  background: linear-gradient(90deg, #ffd36a, #ff6a00, #ffaa66);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  text-shadow: 0 0 10px rgba(255, 215, 0, 0.4);
  animation: shimmer 8s linear infinite;
  font-weight: 600;
  font-size: 1.1rem;
  margin: 0.5rem 0;
}

.footer-icons {
  display: flex;
  justify-content: center;
  gap: 1.4rem;
}

.social-link {
  color: var(--muted);
  transition: color 0.3s ease;
}

.social-link:hover {
  color: var(--gold);
}

.social-icon {
  width: 26px;
  height: 26px;
}

.footer-copy {
  color: var(--muted);
  font-size: 0.9rem;
  margin-top: 1rem;
}

.footer-web {
  color: var(--gold);
  font-size: 1rem;
}
/* Floating Gold Back-to-Top Arrow */
.back-to-top {
  position: fixed;
  bottom: 1.5rem;
  right: 1.5rem;
  z-index: 999;
  opacity: 0;
  transition: opacity 0.3s ease, transform 0.2s ease;
}

.back-to-top svg {
  fill: none;
  stroke: var(--gold, #FFD700);
  stroke-width: 3;
  width: 44px;
  height: 44px;
  filter: drop-shadow(0 0 6px rgba(255, 215, 0, 0.35));
}

.back-to-top:hover {
  transform: translateY(-4px);
}

.back-to-top:hover svg {
  filter: drop-shadow(0 0 10px rgba(255, 215, 0, 0.6));
}