index.html

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    <title>MATH26</title>
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                    <h2 class="text-center" style="margin-bottom: 20px;">Level Selector</h2>
                    <a type="button" class="btn btn-success btn-rounded waves-effect waves-light" onclick="window.location.replace('easy.html')">Easy</a>
                    <a type="button" class="btn btn-primary btn-rounded waves-effect waves-light" onclick="window.location.replace('index.html')">Normal</a>
                    <a type="button" class="btn btn-warning btn-rounded waves-effect waves-light" onclick="window.location.replace('index.html')">Hard</a>
                    <a type="button" class="btn btn-info btn-rounded waves-effect waves-light" style="margin-top: 50px;" onclick="window.location.replace('rule.html')">Rule</a>
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