body {
    font-family: Arial, sans-serif;
    max-width: 1200px;
    margin: 20px auto;
    padding: 20px;
    background: #f5f5f5;
}
h1 {
    text-align: center;
    color: #333;
}
.controls {
    display: flex;
    justify-content: center;
    margin: 20px 0;
}
button {
    padding: 10px 20px;
    font-size: 16px;
    background: #4CAF50;
    color: white;
    border: none;
    border-radius: 5px;
    cursor: pointer;
    margin: 0 5px;
}
button:hover {
    background: #45a049;
}
.check-btn {
    background: #2196F3;
}
.check-btn:hover {
    background: #0b7dda;
}
.solution-btn {
    background: #fbc02d;
}
.solution-btn:hover {
    background: #f9a825;
}
.reset-btn {
    background: #f44336;
}
.reset-btn:hover {
    background: #da190b;
}
.step-title {
    background: #2196F3;
    color: white;
    padding: 15px;
    margin: 20px 0 10px 0;
    border-radius: 5px;
    font-weight: bold;
    font-size: 18px;
}
table {
    width: 100%;
    border-collapse: collapse;
    background: white;
    box-shadow: 0 2px 5px rgba(0,0,0,0.1);
    margin-bottom: 30px;
}
th {
    background: #333;
    color: white;
    padding: 12px;
    text-align: left;
    font-weight: bold;
}
td {
    padding: 12px;
    border-bottom: 1px solid #ddd;
}
tr:hover {
    background: #f5f5f5;
}
.var-name {
    font-weight: bold;
    color: #2196F3;
}
.address {
    font-family: 'Courier New', monospace;
    color: #666;
}
input {
    width: 90%;
    padding: 8px;
    border: 1px solid #ddd;
    border-radius: 3px;
    font-family: 'Courier New', monospace;
}
input.correct {
    background: #c8e6c9;
    border-color: #4CAF50;
}
input.incorrect {
    background: #ffcdd2;
    border-color: #f44336;
}
.code-ref {
    background: #fff3cd;
    padding: 10px;
    border-left: 4px solid #ffc107;
    margin: 10px 0;
    font-family: 'Courier New', monospace;
}
.feedback {
    padding: 15px;
    margin: 20px 0;
    border-radius: 5px;
    font-weight: bold;
    display: none;
}
.feedback.success {
    background: #c8e6c9;
    color: #2e7d32;
    border: 2px solid #4CAF50;
}
.feedback.error {
    background: #ffcdd2;
    color: #c62828;
    border: 2px solid #f44336;
}
.feedback.partial {
    background: #fff9c4;
    color: #f57f17;
    border: 2px solid #fbc02d;
}
.solution-hint {
    background: #e3f2fd;
    padding: 10px;
    margin: 10px 0;
    border-left: 4px solid #2196F3;
    display: none;
    font-size: 14px;
}
@media print {
    button { display: none; }
    .feedback { display: none; }
    .solution-hint { display: none; }
    input { border: none; border-bottom: 1px solid #000; }
}

.explanation {
    background: #4CAF50; 
    color: white; 
    padding: 20px; 
    margin: 30px 0; 
    border-radius: 5px;
}