:root {
  --primary-color: #3498db;
  --secondary-color: #2c3e50;
  --accent-color: #e74c3c;
  --light-color: #ecf0f1;
  --dark-color: #34495e;
  --success-color: #2ecc71;
  --border-radius: 6px;
  --box-shadow: 0 2px 10px rgba(0, 0, 0, 0.1);
}

* {
  margin: 0;
  padding: 0;
  box-sizing: border-box;
  font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
}

body {
  background-color: #f9f9f9;
  color: var(--dark-color);
  line-height: 1.6;
}

.container {
  max-width: 1000px;
  margin: 2rem auto;
  padding: 1rem;
}

h1 {
  text-align: center;
  color: var(--primary-color);
  margin-bottom: 2rem;
}

h2 {
  color: var(--secondary-color);
  margin-bottom: 1rem;
  border-bottom: 2px solid var(--light-color);
  padding-bottom: 0.5rem;
}

h3 {
  color: var(--secondary-color);
  margin: 1.5rem 0 0.5rem;
}

.calculator {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 2rem;
  margin-bottom: 2rem;
}

.input-section, .results-section {
  background-color: white;
  padding: 1.5rem;
  border-radius: var(--border-radius);
  box-shadow: var(--box-shadow);
}

.form-group {
  margin-bottom: 1rem;
}

label {
  display: block;
  margin-bottom: 0.5rem;
  font-weight: 500;
}

input {
  width: 100%;
  padding: 0.75rem;
  border: 1px solid #ddd;
  border-radius: var(--border-radius);
  font-size: 1rem;
  transition: border-color 0.2s;
}

input:focus {
  outline: none;
  border-color: var(--primary-color);
}

button {
  background-color: var(--primary-color);
  color: white;
  border: none;
  padding: 0.75rem 1.5rem;
  border-radius: var(--border-radius);
  font-size: 1rem;
  cursor: pointer;
  transition: background-color 0.2s;
  width: 100%;
  margin-top: 1rem;
}

button:hover {
  background-color: #2980b9;
}

#clear-all {
  background-color: var(--accent-color);
  margin-top: 1rem;
}

#clear-all:hover {
  background-color: #c0392b;
}

.summary {
  background-color: var(--light-color);
  padding: 1rem;
  border-radius: var(--border-radius);
  margin-bottom: 1rem;
}

.summary p {
  margin-bottom: 0.5rem;
}

table {
  width: 100%;
  border-collapse: collapse;
  margin-top: 1rem;
  font-size: 0.95rem;
}

th, td {
  padding: 0.75rem;
  text-align: left;
  border-bottom: 1px solid #ddd;
}

th {
  background-color: var(--light-color);
  font-weight: 600;
}

.delete-btn {
  background-color: var(--accent-color);
  color: white;
  border: none;
  padding: 0.25rem 0.5rem;
  border-radius: 3px;
  cursor: pointer;
  font-size: 0.8rem;
  width: auto;
  margin-top: 0;
}

.delete-btn:hover {
  background-color: #c0392b;
}

.info-section {
  background-color: white;
  padding: 1.5rem;
  border-radius: var(--border-radius);
  box-shadow: var(--box-shadow);
}

@media (max-width: 768px) {
  .calculator {
    grid-template-columns: 1fr;
  }
}
```

```javascript