body {
  margin: 0;
  padding: 0;
  background-color: #000;
  color: #e5e5e7;
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, Helvetica, Arial, sans-serif;
  text-align: center;
}

#container {
  width: 92%;
  max-width: 1300px;
  margin: 0 auto;
}

#header h1 {
  margin-top: 40px;
  margin-bottom: 5px;
  font-size: 2.3em;
  font-weight: 600;
  letter-spacing: -0.02em;
  color: #fff;
}

.tagline {
  margin-bottom: 30px;
  color: #9da3af;
  font-size: 0.95em;
}

#nav ul {
  list-style: none;
  padding: 0;
  margin: 30px 0;
}

#nav li {
  display: inline-block;
  margin: 0 14px;
}

#nav a {
  color: #4da3ff;
  text-decoration: none;
  font-size: 1.05em;
  letter-spacing: -0.01em;
  transition: opacity 0.2s ease;
}

#nav a:hover {
  opacity: 0.65;
}

h2 {
  font-size: 1.9em;
  font-weight: 600;
  margin-top: 20px;
  margin-bottom: 10px;
  letter-spacing: -0.02em;
  color: #fff;
}

.product-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(280px, 1fr));
  gap: 40px;
  margin-top: 40px;
  padding-bottom: 60px;
}

.product-card {
  background-color: #111;
  padding: 20px;
  border-radius: 18px;
  box-shadow: 0px 8px 30px rgba(255, 255, 255, 0.04);
  transition: transform 0.25s ease, box-shadow 0.25s ease;
}

.product-card:hover {
  transform: translateY(-6px);
  box-shadow: 0px 20px 40px rgba(255, 255, 255, 0.08);
}

.product-card img {
  width: 100%;
  height: 200px;
  object-fit: cover;
  border-radius: 14px;
}

.product-card h3 {
  font-size: 1.35em;
  font-weight: 600;
  margin: 15px 0 5px 0;
  color: #fff;
  letter-spacing: -0.01em;
}

.product-card p {
  font-size: 0.95em;
  color: #b5b5b7;
  margin-bottom: 10px;
  line-height: 1.4em;
}

.product-card .price {
  font-size: 1.3em;
  font-weight: 600;
  color: #4da3ff;
  margin-bottom: 15px;
}

.product-card a {
  display: inline-block;
  margin: 6px;
  padding: 10px 16px;
  background-color: #4da3ff;
  color: #000;
  font-weight: 600;
  border-radius: 12px;
  text-decoration: none;
  font-size: 0.95em;
  transition: background-color 0.2s ease, transform 0.2s ease;
}

.product-card a:hover {
  background-color: #76b8ff;
  transform: scale(1.04);
}

.product-large {
  width: 420px;
  border-radius: 18px;
  margin-bottom: 25px;
  box-shadow: 0px 12px 35px rgba(255, 255, 255, 0.06);
}

table {
  width: 95%;
  margin: 25px auto;
  border-collapse: collapse;
  background-color: #0e0e0e;
  border-radius: 18px;
  overflow: hidden;
  color: #e5e5e7;
}

table th, table td {
  border: 1px solid #222;
  padding: 14px;
  font-size: 1em;
}

table th {
  background-color: #161616;
  color: #fff;
  font-weight: 600;
}

input[type="text"] {
  width: 60px;
  padding: 8px;
  border-radius: 10px;
  border: none;
  outline: none;
  text-align: center;
  background-color: #1c1c1e;
  color: #fff;
}

input[type="submit"], .btn {
  padding: 12px 26px;
  background-color: #4da3ff;
  color: #000;
  font-weight: 600;
  font-size: 1em;
  border: none;
  border-radius: 14px;
  cursor: pointer;
  transition: background-color 0.2s ease, transform 0.2s ease;
}

input[type="submit"]:hover, .btn:hover {
  background-color: #76b8ff;
  transform: scale(1.05);
}

ul.error li {
  color: #ff6b6b;
}

.success {
  color: #4da3ff;
  font-weight: 600;
}