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

body {
  font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', sans-serif;
  background: #f0f4f8;
  color: #1e293b;
  min-height: 100vh;
  padding: 16px;
}

.container {
  max-width: 720px;
  margin: 0 auto;
}

h1 {
  font-size: 1.5rem;
  font-weight: 700;
  color: #1e3a5f;
  margin-bottom: 4px;
}

.subtitle {
  color: #64748b;
  font-size: 0.875rem;
  margin-bottom: 20px;
}

h2 {
  font-size: 1rem;
  font-weight: 600;
  margin-bottom: 12px;
  color: #1e293b;
}

.common-section {
  background: #fff;
  border-radius: 12px;
  padding: 16px;
  margin-bottom: 16px;
  box-shadow: 0 1px 4px rgba(0,0,0,0.08);
}

.methods-grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 16px;
  margin-bottom: 16px;
}

@media (max-width: 520px) {
  .methods-grid {
    grid-template-columns: 1fr;
  }
}

.method-card {
  background: #fff;
  border-radius: 12px;
  padding: 16px;
  box-shadow: 0 1px 4px rgba(0,0,0,0.08);
  border-top: 4px solid #94a3b8;
}

.method-card.sea {
  border-top-color: #0ea5e9;
}

.method-card.air {
  border-top-color: #f59e0b;
}

.method-card h2 {
  font-size: 1.05rem;
}

.form-group {
  margin-bottom: 12px;
}

.form-group label {
  display: block;
  font-size: 0.8rem;
  font-weight: 600;
  color: #475569;
  margin-bottom: 4px;
}

.form-group input {
  width: 100%;
  padding: 8px 10px;
  border: 1.5px solid #cbd5e1;
  border-radius: 8px;
  font-size: 0.95rem;
  color: #1e293b;
  background: #f8fafc;
  transition: border-color 0.2s;
}

.form-group input:focus {
  outline: none;
  border-color: #2563eb;
  background: #fff;
}

.method-result {
  margin-top: 12px;
  padding: 10px;
  background: #f1f5f9;
  border-radius: 8px;
  font-size: 0.85rem;
  color: #475569;
  text-align: center;
  min-height: 40px;
  display: flex;
  align-items: center;
  justify-content: center;
}

.calc-btn {
  width: 100%;
  padding: 14px;
  background: #2563eb;
  color: #fff;
  font-size: 1rem;
  font-weight: 700;
  border: none;
  border-radius: 10px;
  cursor: pointer;
  transition: background 0.2s, transform 0.1s;
  margin-bottom: 16px;
}

.calc-btn:hover {
  background: #1d4ed8;
}

.calc-btn:active {
  transform: scale(0.98);
}

.result-section {
  background: #fff;
  border-radius: 12px;
  padding: 20px;
  box-shadow: 0 1px 4px rgba(0,0,0,0.08);
  margin-bottom: 16px;
}

.verdict {
  font-size: 1.2rem;
  font-weight: 700;
  text-align: center;
  padding: 16px;
  border-radius: 10px;
  margin-bottom: 16px;
}

.verdict.sea-wins {
  background: #e0f2fe;
  color: #0369a1;
}

.verdict.air-wins {
  background: #fef3c7;
  color: #92400e;
}

.verdict.tie {
  background: #f0fdf4;
  color: #166534;
}

.breakdown {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 12px;
}

@media (max-width: 400px) {
  .breakdown {
    grid-template-columns: 1fr;
  }
}

.breakdown-item {
  background: #f8fafc;
  border-radius: 8px;
  padding: 12px;
}

.breakdown-item .label {
  font-size: 0.78rem;
  color: #64748b;
  margin-bottom: 4px;
  font-weight: 600;
}

.breakdown-item .value {
  font-size: 0.9rem;
  color: #1e293b;
  font-weight: 600;
}

.breakdown-item .sub {
  font-size: 0.75rem;
  color: #94a3b8;
  margin-top: 2px;
}

.note {
  text-align: center;
  color: #94a3b8;
  margin-top: 8px;
}