* {
  box-sizing: border-box;
}

body {
  margin: 0;
  padding: 0;
  font-family: 'Space Grotesk', system-ui, -apple-system, sans-serif;
  background: radial-gradient(circle at 20% 20%, #f4f7ff, #e8ecf7 25%, #f8fbff 50%);
  color: #0d1b2a;
}

.shell {
  max-width: 880px;
  margin: 48px auto;
  padding: 0 20px;
}

header h1 {
  margin: 0;
  font-size: 32px;
}

header p {
  margin: 6px 0 18px;
  color: #4a6072;
}

.card {
  background: #fff;
  border: 1px solid #e4e9f2;
  border-radius: 16px;
  padding: 20px;
  box-shadow: 0 12px 32px rgba(13, 27, 42, 0.06);
}

label {
  display: block;
  font-weight: 600;
  margin-bottom: 6px;
}

input, select {
  width: 100%;
  padding: 12px;
  border: 1px solid #cdd7e0;
  border-radius: 10px;
  font-size: 15px;
}

.inline {
  display: grid;
  grid-template-columns: 1fr 140px;
  gap: 12px;
  align-items: center;
  margin-bottom: 16px;
}

button {
  padding: 12px 16px;
  border: none;
  border-radius: 12px;
  background: linear-gradient(120deg, #0e7afe, #5ad4f7);
  color: #fff;
  font-weight: 700;
  cursor: pointer;
  transition: transform 0.1s ease, box-shadow 0.2s ease;
}

button:active {
  transform: translateY(1px);
}

button:disabled {
  opacity: 0.5;
  cursor: not-allowed;
}

.options {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(180px, 1fr));
  gap: 14px;
}

.actions {
  margin-top: 16px;
  display: flex;
  align-items: center;
  gap: 12px;
}

#status {
  color: #0e7afe;
  font-weight: 600;
}

.result {
  margin-top: 16px;
  padding: 12px;
  border-radius: 10px;
  background: #f0f6ff;
  border: 1px solid #cde1ff;
  color: #0d1b2a;
}

.hidden {
  display: none;
}

@media (max-width: 640px) {
  .inline {
    grid-template-columns: 1fr;
  }

  button {
    width: 100%;
  }
}