Html panel is not responsive in .net

Question

I have created a panel in Asp.net with html and css.but this is not responsive.If resolution change its broken.How to fix it

<asp:PlaceHolder ID="phFbLearnMore" runat="server" Visible="false" >
<div class="divFBlearnMore col-lg-12 " id="divFBlearnMoreId">
<span class="fbTextContent col-lg-6 ">Increase exposure to your job postings by sending them to the Facebook Jobs Marketplace.</span>
<button id="FbButtonLink" class="fbButtonContent col-lg-3 ">Opt In</button>
<button id="closeButton"class="CloseButtonContent col-lg-3">X</button>
</div>
</asp:PlaceHolder>

css i have used below

.divFBlearnMore {
position: absolute;
padding-bottom: 7px;
color: white;
z-index: 1;
width: 100%;
height: 35px;
float: right;
border: 1px solid #0f9fd8;
background-color: #0f9fd8;
font-size: 14px;
margin-top: -84px;
margin-left: -190px;
padding-top: 18px;
}
.fbTextContent {
margin-left: 55px;
}
.fbButtonContent {
cursor: pointer;
border: 1px solid #FFFFFF;
background-color: #0f9fd8;
color: #FFFFFF;
border-radius: 3px;
margin-left: 770px;
margin-bottom: 50%;
padding-left: 37px;
padding-right: 37px;
padding-top: 6px;
padding-bottom: 5px;
}
.CloseButtonContent {
cursor: pointer;
color: #FFFFFF;
background-color: #0f9fd8;
border: 1px solid #0f9fd8;
float: right;
margin-right: 40px;
padding-top: 7px;
}