Double column form not responsive

Hello,

I would like to implement the form on two columns, but I can not make it responsive nonstante the ema in use it is.

The CSS you use is this:

# Two-column {
width: 550px;
}
# two-column #left {
width: 300px;
float: left;
}
# two-column #right {
width: 250px;
float: right;
}
# two-column p {
margin-bottom: 12px;
}
# two-column input [type = “text”] {
border: none;
border: 1px solid # 000;
font-size: 14px;
-webkit-border-radius: 5px;
-moz-border-radius: 5px;
border-radius: 5px;
width: 540px;
padding: 5px;
}

# two-column #right input [type = “text”], # two-column #left input [type = “text”] {
width: 240px;
}

# two-column input [type = “email”] {
border: none;
border: 1px solid # 000;
font-size: 14px;
-webkit-border-radius: 5px;
-moz-border-radius: 5px;
border-radius: 5px;
width: 540px;
padding: 5px;
}
# two-column #right input [type = “email”], # two-column #left input [type = “email”] {
width: 240px;
}

# two-column textarea {
position: relative;
padding: 5px;
border: 1px solid # 000;
-webkit-border-radius: 5px;
-moz-border-radius: 5px;
border-radius: 5px;
width: 540px;
}

input.wpcf7-form-submit-control.wpcf7 {
background: # 0c00ff;
cursor: pointer;
color: #fff;
}

Can you help me?

Thank you