.back-home {
    display: inline-block;
    margin: 15px 20px;
    padding: 10px 15px;
    background-color: #34495e;
    color: #ecf0f1;
    text-decoration: none;
    font-weight: bold;
    border-radius: 4px;
    box-shadow: 0 2px 4px rgba(0,0,0,0.1);
    transition: background-color 0.3s ease, transform 0.2s ease;
}
.back-home:hover {
    background-color: #2c3e50;
    transform: translateX(-3px);
}


* {
    box-sizing: border-box;
}

body {
    font-family: Arial, Helvetica, sans-serif;
    background-color: #f9f9f9;
    color: #333;
    line-height: 1.6;
    margin: 0;
    padding: 0;
}

.page-title {
    background-color: #2c3e50;
    color: white;
    text-align: center;
    padding: 20px 0;
    margin-bottom: 20px;
}

.page-title p {
    margin: 5px 0 0 0;
    font-size: 0.9em;
    color: #e2e8f0;
}

.content {
    max-width: 800px;
    margin: 0 auto;
    padding: 20px 40px;
    background-color: white;
    border: 1px solid #ddd;
    border-radius: 4px;
    box-shadow: 0 2px 4px rgba(0,0,0,0.05);
}


.question-block {
    margin-bottom: 30px;
    padding-bottom: 20px;
    border-bottom: 1px dashed #ccc;
}
.question-block:last-child {
    border-bottom: none;
}

.question-block h3 {
    color: #2c3e50;
    margin-bottom: 15px;
    font-size: 1.1em;
}

.question-block code {
    background-color: #f1f1f1;
    padding: 2px 5px;
    border-radius: 3px;
    font-family: Consolas, monospace;
}

.option-label {
    display: block;
    margin-bottom: 10px;
    cursor: pointer;
    padding: 8px;
    border-radius: 4px;
    border: 1px solid transparent;
    transition: background-color 0.2s, border-color 0.2s;
}


.option-label:hover {
    background-color: #f8f9fa;
    border-color: #ddd;
}




.feedback {
    display: block;
    margin-top: 5px;
    margin-left: 20px;
    font-size: 0.9em;
    font-weight: bold;
    
    
    max-height: 0;
    opacity: 0;
    overflow: hidden;
    transition: all 0.3s ease;
}

.feedback.correct {
    color: #27ae60; 
}

.feedback.wrong {
    color: #c0392b; 
}



input[type="radio"]:checked ~ .feedback {
    max-height: 50px;
    opacity: 1;
    margin-top: 10px;
}


input[type="radio"][value="correct"]:checked {
    accent-color: #27ae60;
}
input[type="radio"][value="wrong"]:checked {
    accent-color: #c0392b;
}


.option-label:has(input[type="radio"][value="correct"]:checked) {
    background-color: rgba(39, 174, 96, 0.1);
    border-color: #27ae60;
}
.option-label:has(input[type="radio"][value="wrong"]:checked) {
    background-color: rgba(192, 57, 43, 0.1);
    border-color: #c0392b;
}


.back-btn {
    position: absolute;
    top: 15px;
    left: 15px;
    width: 40px;
    height: 40px;
    background-color: #fff;
    color: #333;
    border: 1px solid #ddd;
    border-radius: 50%;
    display: flex;
    justify-content: center;
    align-items: center;
    text-decoration: none;
    font-size: 1.2rem;
    font-weight: bold;
    box-shadow: 0 2px 4px rgba(0,0,0,0.1);
    transition: transform 0.2s;
    z-index: 1000;
}
.back-btn:hover {
    transform: scale(1.1);
    background-color: #f4f4f4;
}