:root {
  --bg: #0d1117;
  --card: #161b22;
  --border: #30363d;
  --text: #c9d1d9;
  --muted: #8b949e;
  --link: #58a6ff;
  --accent: #79c0ff;
  --shadow: 0 8px 24px rgba(0,0,0,0.4);
  --btn-bg: #238636;
  --btn-hover: #2ea043;
}

* { box-sizing: border-box; }

body {
  margin: 0;
  font-family: system-ui, sans-serif;
  background: var(--bg);
  color: var(--text);
  line-height: 1.6;
}

.container {
  max-width: 1180px;
  margin: 0 auto;
  padding: 20px 15px;
}

.header {
  text-align: center;
  margin-bottom: 40px;
}

.nav {
  display: flex;
  justify-content: center;
  gap: 32px;
  margin-top: 20px;
}

.nav a {
  text-decoration: none;
  color: var(--link);
  font-weight: 600;
}

.nav a:hover {
  text-decoration: underline;
}

.main-flex {
  display: flex;
  gap: 40px;
  flex-direction: column;
}

@media (min-width: 992px) {
  .main-flex { flex-direction: row; }
}

.products-section {
  flex: 3;
}

.products-flex {
  display: grid;
  grid-template-columns: 1fr;
  gap: 28px;
}

@media (min-width: 768px) {
  .products-flex { grid-template-columns: repeat(2, 1fr); }
}

@media (min-width: 1200px) {
  .products-flex { grid-template-columns: repeat(3, 1fr); }
}

.product-card {
  background: var(--card);
  border: 1px solid var(--border);
  border-radius: 12px;
  padding: 28px;
  box-shadow: var(--shadow);
  transition: transform 0.3s ease;
}

.product-card:hover {
  transform: translateY(-8px);
}

.product-icon {
  font-size: 4.5rem;
  margin-bottom: 16px;
  text-align: center;
}

.benefits-flex {
  display: grid;
  grid-template-columns: 1fr;
  gap: 20px;
  margin: 48px 0;
}

@media (min-width: 768px) {
  .benefits-flex { grid-template-columns: repeat(3, 1fr); }
}

.benefit-block {
  background: #21262d;
  border-radius: 10px;
  padding: 20px;
  text-align: center;
  font-weight: 600;
}

.form-aside {
  flex: 1.3;
}

.card {
  background: var(--card);
  border: 1px solid var(--border);
  border-radius: 12px;
  padding: 32px;
  box-shadow: var(--shadow);
}

.muted { color: var(--muted); }

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

a:hover { text-decoration: underline; }

form label {
  display: block;
  margin: 20px 0 8px;
  font-weight: 600;
}

.form-input {
  width: 100%;
  padding: 14px 18px;
  border: 1px solid var(--border);
  border-radius: 8px;
  font-size: 1.05rem;
  background: #0d1117;
  color: var(--text);
  transition: border-color 0.2s;
}

.form-input:focus {
  outline: none;
  border-color: var(--accent);
  box-shadow: 0 0 0 3px rgba(121,192,255,0.2);
}

.form-button {
  background: var(--btn-bg);
  color: white;
  border: none;
  padding: 18px;
  border-radius: 8px;
  font-size: 1.2rem;
  font-weight: 600;
  cursor: pointer;
  margin-top: 28px;
  width: 100%;
  transition: background 0.2s;
}

.form-button:hover {
  background: var(--btn-hover);
}

.payment-note {
  margin-top: 28px;
  text-align: center;
  font-weight: 600;
  color: var(--text);
  background: #21262d;
  padding: 16px;
  border-radius: 8px;
}

details {
  margin-bottom: 20px;
}

summary {
  cursor: pointer;
  font-weight: 600;
  color: var(--link);
  list-style: none;
}

summary::-webkit-details-marker { display: none; }

ul.muted {
  list-style: disc;
  padding-left: 24px;
  margin: 0;
}

footer {
  text-align: center;
  padding: 60px 20px 30px;
  margin-top: 100px;
  border-top: 1px solid var(--border);
  color: var(--muted);
}