/* Basic Reset & Body Styling */
body {
    background-color: #f4f7f9;
    font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, Helvetica, Arial, sans-serif;
    color: #333;
    margin: 0;
    padding: 2rem;
    display: flex;
    justify-content: center;
    align-items: flex-start;
    min-height: 100vh;
}

/* Main Calculator Container */
.calculator-container {
    background-color: #ffffff;
    padding: 2.5rem;
    border-radius: 8px;
    box-shadow: 0 4px 12px rgba(0, 0, 0, 0.08);
    width: 100%;
    max-width: 600px;
    transition: all 0.3s ease;
}

h1 {
    text-align: center;
    color: #2c3e50;
    margin-bottom: 2rem;
    font-weight: 600;
}

/* Form Styling */
.form-group {
    margin-bottom: 1.5rem;
}

label {
    display: block;
    margin-bottom: 0.5rem;
    font-weight: 500;
    color: #555;
}

.input-group {
    display: flex;
}

.input-group-prepend .input-group-text {
    background-color: #e9ecef;
    border: 1px solid #ced4da;
    border-right: none;
    padding: 0.5rem 1rem;
    border-radius: 0.25rem 0 0 0.25rem;
}

input[type="number"],
select {
    width: 100%;
    padding: 0.75rem;
    border: 1px solid #ced4da;
    border-radius: 4px;
    font-size: 1rem;
    transition: border-color 0.2s ease, box-shadow 0.2s ease;
}

input[type="number"]:focus,
select:focus {
    outline: none;
    border-color: #80bdff;
    box-shadow: 0 0 0 0.2rem rgba(0, 123, 255, 0.25);
}

/* Checkbox Styling */
.checkbox-group {
    display: flex;
    align-items: center;
    gap: 0.75rem;
    margin-top: 1rem;
}

input[type="checkbox"] {
    width: 1.25em;
    height: 1.25em;
}

/* Calculate Button */
.btn-calculate {
    width: 100%;
    padding: 0.85rem;
    font-size: 1.1rem;
    font-weight: 600;
    color: #fff;
    background-color: #007bff;
    border: none;
    border-radius: 4px;
    cursor: pointer;
    transition: background-color 0.2s ease;
}

.btn-calculate:hover {
    background-color: #0056b3;
}

/* Result Card */
.result-card {
    margin-top: 2rem;
    background-color: #f8f9fa;
    padding: 1.5rem;
    border-radius: 8px;
    border: 1px solid #e9ecef;
    display: none; /* Hidden by default */
}

.result-card h3 {
    margin-top: 0;
    color: #2c3e50;
    border-bottom: 2px solid #e0e0e0;
    padding-bottom: 0.5rem;
    margin-bottom: 1rem;
}

.result-item {
    display: flex;
    justify-content: space-between;
    padding: 0.75rem 0;
    border-bottom: 1px solid #e9ecef;
}

.result-item:last-child {
    border-bottom: none;
}

.result-item span {
    font-weight: 500;
}

.result-item .value {
    color: #007bff;
    font-weight: 600;
}

.result-item.total .value {
    color: #28a745;
    font-size: 1.2rem;
}

/* Hidden class for dynamic options */
.hidden {
    display: none;
}

/* Footer Links */
.footer-links a {
    color: #6c757d;
    text-decoration: none;
}

.footer-links a:hover {
    color: #0d6efd;
    text-decoration: underline;
}