:root {
    --bg-gray: #f0f2f5;
    --card-white: #ffffff;
    --section-bg: #f8f9fa;
    --text-dark: #212529;
    --text-light: #6c757d;
    --red-btn: #c94444;
}

body {
    background-color: var(--bg-gray);
    font-family: 'Roboto', sans-serif;
    display: flex;
    justify-content: center;
    padding: 40px 20px;
    margin: 0;
}

.registration-card {
    background-color: var(--card-white);
    width: 100%;
    max-width: 800px;
    padding: 40px;
    border-radius: 8px;
    box-shadow: 0 4px 20px rgba(0,0,0,0.08);
}

.main-title {
    font-size: 26px;
    margin-bottom: 30px;
    color: var(--text-dark);
}

.form-section {
    background-color: var(--section-bg);
    padding: 25px;
    border-radius: 8px;
    margin-bottom: 25px;
    border: 1px solid #e9ecef;
}

.section-title {
    font-weight: bold;
    color: var(--text-light);
    margin-top: 0;
    margin-bottom: 20px;
    text-transform: uppercase;
    font-size: 14px;
    letter-spacing: 1px;
}

.grid-container {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 20px;
}

.field {
    display: flex;
    flex-direction: column;
}

.field label {
    font-size: 12px;
    font-weight: bold;
    color: #adb5bd;
    margin-bottom: 5px;
}

input {
    padding: 10px;
    border: 1px solid #dee2e6;
    border-radius: 4px;
    font-size: 14px;
}

.single {
    max-width: 300px;
}

.regulation-box {
    background: white;
    padding: 15px;
    border: 1px solid #dee2e6;
    font-size: 13px;
    line-height: 1.6;
    color: #495057;
    margin-bottom: 15px;
    max-height: 250px; /* Aumentado un poco para que se lea mejor el reglamento largo */
    overflow-y: auto;
}

.checkbox-field {
    display: flex;
    align-items: center;
    gap: 10px;
    font-size: 14px;
}

.button-area {
    text-align: center;
    margin-top: 20px;
}

.submit-btn {
    background-color: var(--red-btn);
    color: white;
    border: none;
    padding: 15px 60px;
    border-radius: 4px;
    font-weight: bold;
    text-transform: uppercase;
    cursor: pointer;
    transition: background 0.3s;
}

.submit-btn:disabled {
    background-color: #fab1a0;
    cursor: not-allowed;
}

.hidden {
    display: none;
}

@media (max-width: 600px) {
    .grid-container { grid-template-columns: 1fr; }
}