body {
    font-family: Arial, sans-serif;
    background-color: #f0f0f0;
    color: #333;
    margin: 0;
    padding: 0;
}

.header {
    background-color: #2c3e50;
    padding: 10px 0;
}

.header h1 {
    color: white;
    font-size: 24px;
    margin: 0;
}

.header a {
    color: white;
    text-decoration: none;
    margin-left: 20px;
}

.main-container {
    max-width: 800px;
    margin: 20px auto;
    background-color: white;
    box-shadow: 0 0 10px rgba(0, 0, 0, 0.1);
    padding: 30px;
    border-radius: 5px;
}

.form-group {
    margin-bottom: 15px;
    display: flex;
    align-items: center;
}

.form-group > label {
    display: inline-block;
    width: 120px;
    text-align: right;
    margin-right: 15px;
    flex-shrink: 0;
}

.form-control {
    display: inline-block;
    background-color: #f8f9fa;
    border: 1px solid #ced4da;
    padding: 5px 10px;
    border-radius: 4px;
}

.form-control:focus {
    background-color: white;
    border-color: #80bdff;
    box-shadow: 0 0 0 0.2rem rgba(0, 123, 255, .25);
}

.btn-group {
    margin-bottom: 20px;
}

.btn-group label {
    border: 1px solid #007bff;
    background-color: white;
    color: #007bff;
    padding: 5px 10px;
    cursor: pointer;
}

.btn-group label:first-of-type {
    border-radius: 4px 0 0 4px;
}

.btn-group label:last-of-type {
    border-radius: 0 4px 4px 0;
}

.btn-group input[type="radio"]:checked + label {
    background-color: #007bff;
    color: white;
}

.btn-primary, .calculate-btn, .reset-btn {
    padding: 10px 20px;
    font-size: 18px;
    border: none;
    border-radius: 4px;
    cursor: pointer;
}

.btn-primary, .calculate-btn {
    background-color: #007bff;
    color: white;
}

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

.reset-btn {
    background-color: #6c757d;
    color: white;
    margin-left: 10px;
}

.reset-btn:hover {
    background-color: #5a6268;
}

.security-note {
    font-size: 12px;
    color: #28a745;
    margin-bottom: 20px;
}

.nav-tabs {
    margin-bottom: 20px;
}

.sources {
    margin-top: 30px;
    padding-top: 20px;
    border-top: 1px solid #dee2e6;
    font-size: 14px;
    color: #6c757d;
}

.gender-group {
    display: inline-flex;
    align-items: center;
}

.gender-group input[type="radio"] {
    margin-right: 5px;
}

.gender-group label.form-check-label {
    margin-right: 20px;
    width: auto !important;
    display: inline-block !important;
    text-align: left !important;
}

.unit-toggle {
    float: right;
}

.input-group {
    display: inline-block;
}

.input-group input,
.input-group select {
    width: 60px;
}

#heightImperial {
    width: 100px !important;
}

#heightCm {
    width: 60px !important;
}

.bmi-input-group {
    display: inline-block;
    vertical-align: middle;
}

.bmi-input-group input[type="number"],
.bmi-input-group select {
    width: 60px !important;
    display: inline-block !important;
}

.results-box {
    background-color: #ffffc0;
    padding: 15px;
    border-radius: 5px;
    height: calc(50% - 10px);
    margin-bottom: 20px;
}

.results-box h3 {
    margin-top: 0;
    font-size: 1.2rem;
}

.result-value {
    font-size: 2.5rem;
    font-weight: bold;
    line-height: 1.2;
}

.bmi-category {
    font-size: 1.2rem;
    font-weight: bold;
    color: #28a745;
}

.graph-placeholder {
    border: 1px solid #ddd;
    border-radius: 5px;
}

@media (max-width: 768px) {
    .results-box {
        height: auto;
        margin-bottom: 15px;
    }
}

.results-grid, .macros-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
    gap: 20px;
}

.result-item, .macro-item {
    text-align: center;
}

.result-value, .macro-value {
    font-size: 24px;
    font-weight: bold;
}

.recalculate form {
    font-size: 0.9rem;
    flex-wrap: wrap;
}

.recalculate .form-group {
    margin-bottom: 0.5rem;
}

.recalculate .form-control-sm,
.recalculate .form-select-sm {
    font-size: 0.9rem;
    height: calc(1.5em + 0.5rem + 2px);
    padding: 0.25rem 0.5rem;
}

.recalculate label {
    margin-bottom: 0;
}

@media (max-width: 768px) {
    .recalculate form {
        flex-direction: column;
        align-items: flex-start;
    }
    
    .recalculate .form-group {
        margin-bottom: 0.5rem;
    }
}

.results-box {
    background-color: #f0f0f0;
    border-radius: 8px;
    padding: 20px;
    height: 200px;
    box-shadow: 0 4px 6px rgba(0, 0, 0, 0.1);
}
.result-value {
    font-size: 3rem;
    font-weight: bold;
}
.bmi-category-underweight { color: #3b82f6; }
.bmi-category-normal { color: #10b981; }
.bmi-category-overweight { color: #f59e0b; }
.bmi-category-obese { color: #ef4444; }

.percentile-explanation {
    font-size: 0.8em;
    text-align: center;
}

.input-group-sm > .form-control,
    .input-group-sm > .form-select,
    .input-group-sm > .input-group-text {
        padding: 0.25rem 0.5rem;
        font-size: 0.875rem;
        line-height: 1.5;
    }
    
    .form-select {
        padding-right: 2rem;
    }
    
    .btn-sm {
        padding: 0.25rem 0.5rem;
        font-size: 0.875rem;
        line-height: 1.5;
    }