.fraction-input {
    font-size: 1.2rem;
    text-align: center;
}
.fraction-divider {
    border-top: 2px solid #6c757d;
    margin: 5px auto;
    width: 80px;
}
.operation-select {
    font-size: 1.5rem;
    font-weight: bold;
    text-align: center;
    height: 50px;
}
.result-container {
    background-color: #f8f9fa;
    border-radius: 10px;
    padding: 20px;
    margin-top: 20px;
    border-left: 5px solid #28a745;
}
.result-fraction {
    font-size: 1.8rem;
    font-weight: bold;
    color: #dc3545;
    margin: 10px 0;
    min-height: 60px;
}
.btn-operation {
    min-width: 120px;
}
.step-explanation {
    background-color: #f0f7ff;
    border-radius: 8px;
    padding: 15px;
    margin-top: 20px;
    font-size: 0.9rem;
}
.example-list {
    list-style-type: none;
    padding-left: 0;
}
.example-list li {
    padding: 5px 0;
    border-bottom: 1px dashed #dee2e6;
}
.example-list li:last-child {
    border-bottom: none;
}
.example-expression {
    font-weight: bold;
    color: #007bff;
}
.calculation-area {
    background-color: #f9f9f9;
    border-radius: 8px;
    padding: 20px;
    border: 1px solid #e9ecef;
}
.operation-buttons {
    display: flex;
    justify-content: center;
    gap: 10px;
    margin: 15px 0;
}
.operation-btn {
    width: 50px;
    height: 50px;
    font-size: 1.5rem;
    font-weight: bold;
}
.btn-selected {
    background-color: #28a745;
    border-color: #28a745;
    color: white;
}
.history-item {
    padding: 8px 12px;
    margin-bottom: 5px;
    background-color: #f8f9fa;
    border-radius: 5px;
    border-left: 3px solid #007bff;
}