:root {
    --red: #d82c20;
    --white: #ffffff;
    --font: 'Roboto', sans-serif;
    --gap: 1rem;
}
.crs-calculator-container {
    background: var(--white);
    border: 2px solid var(--red);
    border-radius: 10px;
    max-width: 720px;
    margin: 2rem auto;
    padding: var(--gap);
    font-family: var(--font);
    box-shadow: 0 4px 12px rgba(0,0,0,0.1);
}
.crs-calculator-container h2 {
    color: var(--red);
    text-align: center;
    font-size: 2rem;
    margin-bottom: var(--gap);
}
.intro {
    text-align: center;
    margin-bottom: var(--gap);
}
.seo-section h3 {
    margin-top: var(--gap);
    color: #333;
}
.seo-section p, .seo-section ul, .seo-section ol, .seo-section table, .seo-section dl {
    margin-bottom: var(--gap);
    line-height: 1.5;
}
.seo-section table {
    width: 100%;
    border-collapse: collapse;
}
.seo-section table, .seo-section th, .seo-section td {
    border: 1px solid #ccc;
}
.seo-section th, .seo-section td {
    padding: 0.5rem;
    text-align: left;
}
form fieldset {
    border: none;
    margin-bottom: var(--gap);
}
legend {
    font-size: 1.2rem;
    font-weight: 500;
    margin-bottom: 0.5rem;
}
.grid-2cols {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
    gap: var(--gap);
}
.field-group {
    margin-bottom: var(--gap);
}
.field-group label {
    display: block;
    margin-bottom: 0.25rem;
    font-weight: 500;
}
input[type='number'], select {
    width: 100%;
    padding: 0.5rem;
    border: 1px solid #ccc;
    border-radius: 6px;
    font-size: 1rem;
}
.checkbox-group {
    display: flex;
    align-items: center;
    gap: 0.5rem;
}
.btn-primary {
    background: var(--red);
    color: var(--white);
    width: 100%;
    padding: 0.75rem;
    font-size: 1.1rem;
    border: none;
    border-radius: 6px;
    cursor: pointer;
    transition: background 0.3s;
}
.btn-primary:hover,
.btn-primary:focus {
    background: #b12019;
}
.result-container {
    margin-top: var(--gap);
    text-align: center;
    font-size: 1.2rem;
}
@media (max-width: 480px) {
    .crs-calculator-container { padding: 0.5rem; }
    .btn-primary { font-size: 1rem; }
}