/* Design system: white + #0056b3 only */
:root {
  --primary: #0056b3;
}

* {
  box-sizing: border-box;
  margin: 0;
  padding: 0;
}

html, body {
  height: 100%;
}

body {
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, Oxygen, Ubuntu, Cantarell, "Fira Sans", "Droid Sans", "Helvetica Neue", Arial, sans-serif;
  color: rgba(0, 86, 179, 0.95);
  background: #ffffff;
  display: grid;
  place-items: start center;
  padding: 32px 16px;
}

.container {
  width: 100%;
  max-width: 960px;
}

.header {
  text-align: center;
  margin-bottom: 20px;
}

h1 {
  color: var(--primary);
  font-size: 28px;
  margin-bottom: 6px;
}

.subtitle {
  color: rgba(0, 86, 179, 0.75);
  font-size: 14px;
}

.card {
  background: #ffffff;
  border: 1px solid rgba(0, 86, 179, 0.18);
  border-radius: 14px;
  box-shadow: 0 8px 26px rgba(0, 86, 179, 0.10);
  padding: 20px;
}

.grid {
  display: grid;
  grid-template-columns: 1fr;
  gap: 14px;
}

@media (min-width: 640px) {
  .grid {
    grid-template-columns: repeat(2, 1fr);
  }
}

.form-group label {
  display: block;
  font-weight: 600;
  color: rgba(0, 86, 179, 0.9);
  margin-bottom: 6px;
}

.form-group select {
  width: 100%;
  padding: 12px 14px;
  font-size: 15px;
  color: rgba(0, 86, 179, 0.95);
  background: #ffffff;
  border: 1px solid rgba(0, 86, 179, 0.35);
  border-radius: 12px;
  outline: none;
  transition: box-shadow 0.2s ease, border-color 0.2s ease, transform 0.06s ease;
  -webkit-appearance: none;
  -moz-appearance: none;
  appearance: none;
  background-image: url('data:image/svg+xml;utf8,<svg xmlns="http://www.w3.org/2000/svg" width="24" height="24" viewBox="0 0 24 24" fill="none" stroke="%230056b3" stroke-width="2" stroke-linecap="round" stroke-linejoin="round"><polyline points="6 9 12 15 18 9"/></svg>');
  background-repeat: no-repeat;
  background-position: right 12px center;
  background-size: 18px;
}

.form-group select:hover {
  border-color: rgba(0, 86, 179, 0.6);
}

.form-group select:focus {
  border-color: var(--primary);
  box-shadow: 0 0 0 3px rgba(0, 86, 179, 0.18);
}

.btn-primary {
  margin-top: 8px;
  width: 100%;
  padding: 12px 16px;
  border: none;
  border-radius: 12px;
  background: var(--primary);
  color: #ffffff;
  font-weight: 700;
  letter-spacing: 0.2px;
  font-size: 16px;
  cursor: pointer;
  transition: transform 0.06s ease, box-shadow 0.2s ease, opacity 0.2s ease;
  box-shadow: 0 10px 22px rgba(0, 86, 179, 0.30);
}

.btn-primary:hover {
  transform: translateY(-1px);
}

.btn-primary:active {
  transform: translateY(0);
  box-shadow: 0 6px 16px rgba(0, 86, 179, 0.28);
}

form:invalid .btn-primary {
  opacity: 0.6;
  cursor: not-allowed;
}

.result {
  margin-top: 16px;
  padding: 14px 16px;
  border-radius: 14px;
  border: 1px solid rgba(0, 86, 179, 0.22);
  background: linear-gradient(0deg, rgba(0, 86, 179, 0.045), rgba(0, 86, 179, 0.045)), #ffffff;
  color: rgba(0, 86, 179, 0.98);
  font-size: 16px;
}