My20486_03_CalcMVC.Models.Calc1

@model My20486_03_CalcMVC.Models.Calc1

@{
    Layout = null;
    string cssPlus = "", cssMinus = "";
    if(Model.Operation == "+") {
        cssPlus = "pressed";
    }
    if (Model.Operation == "-")
    {
        cssMinus = "pressed";
    }
}

<!DOCTYPE html>

<html>
<head>
    <meta name="viewport" content="width=device-width" />
    <title>Index</title>
    <style>
        .pressed {
            background-color:pink;
        }
    </style>
</head>
<body>
    <div>
        <form action="DoCalc" method="post">
            <input type="text" name="x" value="@Model.X" /> <br />
            <input type="text" name="y" value="@Model.Y" /> <br />
            <input type="submit" name="operation" value="+" class="@cssPlus" />
            <input type="submit" name="operation" value="-" class="@cssMinus" /> <br />
            <input type="text" name="z" value="@Model.Z" />
        </form>
    </div>
</body>
</html>