body {
font-family: Arial, sans-serif;
background-color: #f0f0f0;
}
.number, .subtrahend {
cursor: pointer;
margin: 5px;
padding: 10px;
border-radius: 5px;
border: 2px solid #007bff;
display: inline-block;
width: 38px;
text-align: center;
font-size: 30px;
background-color: #fff;
}
.selected {
background-color: #007bff;
color: #fff;
}
.equation {
font-size: 60px;
text-align: center;
margin: 30px 0;
}
.correct {
color: green;
font-size: 40px;
}
.wrong {
color: red;
font-size: 40px;
}
#subtrahendSelection, #answerSelection {
display: flex;
flex-wrap: wrap;
justify-content: center;
margin-bottom: 20px;
}
.info {
font-size: 20px;
text-align: center;
margin: 10px;
}
.footer {
text-align: center;
font-size: 14px;
color: #999;
margin-top: 20px;
}
.button {
padding: 10px 20px;
font-size: 20px;
background-color: #007bff;
color: white;
border: none;
border-radius: 5px;
cursor: pointer;
}
.button:hover {
background-color: #0056b3;
}