body {
}

.btn,
.btnBold,
.btnItalic,
.btnUnderline
{
    width: 25px;
    height: 25px;
}

.btnBold
{
    font-weight: bold;
}

.btnItalic
{
    font-style: italic;
}

.btnUnderline
{
    text-decoration: underline;
}