:root {
  --bg: #0e1116;
  --panel: #161b22;
  --border: #2a303a;
  --text: #e6edf3;
  --muted: #9aa7b2;
  --accent: #76b900; /* NVIDIA green */
  --accent-dark: #5c9200;
}

* { box-sizing: border-box; }

body {
  margin: 0;
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, Helvetica, Arial, sans-serif;
  background: var(--bg);
  color: var(--text);
  line-height: 1.5;
}

header {
  background: var(--panel);
  border-bottom: 1px solid var(--border);
  padding: 14px 20px;
  display: flex;
  align-items: center;
  justify-content: space-between;
  flex-wrap: wrap;
  gap: 10px;
}

header .brand {
  font-weight: 700;
  font-size: 1.2rem;
  color: var(--accent);
  text-decoration: none;
}

nav a {
  color: var(--muted);
  text-decoration: none;
  margin-left: 16px;
  font-size: 0.92rem;
}

nav a:hover { color: var(--text); }

main {
  max-width: 980px;
  margin: 0 auto;
  padding: 28px 20px 60px;
}

h1 { font-size: 1.8rem; margin-bottom: 6px; }
h2 { font-size: 1.35rem; margin-top: 34px; }
p.lead { color: var(--muted); margin-top: 0; }

.card {
  background: var(--panel);
  border: 1px solid var(--border);
  border-radius: 10px;
  padding: 18px 20px;
  margin-bottom: 18px;
}

.product-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(260px, 1fr));
  gap: 16px;
}

.product-card h3 { margin: 0 0 2px; }
.product-card .category { color: var(--accent); font-size: 0.82rem; text-transform: uppercase; letter-spacing: 0.04em; }
.stat { margin-top: 10px; }
.stat .value { font-weight: 700; font-size: 1.05rem; }
.stat .explain { color: var(--muted); font-size: 0.86rem; margin-top: 2px; }

.paths {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(240px, 1fr));
  gap: 16px;
}
.path-card {
  background: var(--panel);
  border: 1px solid var(--border);
  border-radius: 10px;
  padding: 20px;
  text-align: center;
}
.btn {
  display: inline-block;
  background: var(--accent);
  color: #06210a;
  font-weight: 700;
  padding: 10px 18px;
  border-radius: 8px;
  text-decoration: none;
  border: none;
  cursor: pointer;
  font-size: 0.95rem;
}
.btn:hover { background: var(--accent-dark); }
.btn-secondary {
  background: transparent;
  border: 1px solid var(--border);
  color: var(--text);
}

table {
  width: 100%;
  border-collapse: collapse;
  margin-top: 10px;
}
th, td {
  text-align: left;
  padding: 8px 10px;
  border-bottom: 1px solid var(--border);
  font-size: 0.92rem;
}
th { color: var(--muted); font-weight: 600; }

.math-line {
  font-family: "SF Mono", Menlo, Consolas, monospace;
  background: #0b0e13;
  border: 1px solid var(--border);
  border-radius: 6px;
  padding: 10px 12px;
  margin: 8px 0;
  font-size: 0.9rem;
  overflow-x: auto;
}

.badge {
  display: inline-block;
  background: rgba(118,185,0,0.15);
  color: var(--accent);
  border-radius: 6px;
  padding: 2px 8px;
  font-size: 0.78rem;
  font-weight: 600;
}

.conversions { display: flex; gap: 20px; flex-wrap: wrap; margin-top: 10px; }
.conversion-item { background: #0b0e13; border: 1px solid var(--border); border-radius: 8px; padding: 10px 14px; min-width: 160px; }
.conversion-item .num { font-size: 1.3rem; font-weight: 700; color: var(--accent); }
.conversion-item .label { color: var(--muted); font-size: 0.82rem; }

.honest-note {
  border-left: 3px solid var(--accent);
  padding-left: 12px;
  color: var(--muted);
  font-size: 0.9rem;
  margin-top: 14px;
}

form.purchase-form label { display: block; margin-top: 14px; font-weight: 600; font-size: 0.9rem; }
form.purchase-form input, form.purchase-form select {
  width: 100%;
  padding: 9px 10px;
  margin-top: 6px;
  border-radius: 6px;
  border: 1px solid var(--border);
  background: #0b0e13;
  color: var(--text);
  font-size: 0.95rem;
}
.error-box {
  background: rgba(220,60,60,0.12);
  border: 1px solid #a33;
  color: #ff9d9d;
  padding: 10px 14px;
  border-radius: 8px;
  margin-bottom: 14px;
}
.confirmation-box {
  text-align: center;
  padding: 40px 20px;
}
.confirmation-box .req-number {
  font-size: 2rem;
  font-weight: 800;
  color: var(--accent);
  margin: 10px 0;
}
footer {
  text-align: center;
  color: var(--muted);
  font-size: 0.8rem;
  padding: 20px;
}