Adding A responsive Footer to a website. Footer is on master page and should be shown on every content page

Question

How To Add Footer in asp.net Which adjusts automatically with content on the page and the screen size.

I have a Footer on a master page. and I want all the content pages should adapt automatically to the content on the screen or screen size

I have tried.

footer {
        background-color: lightgray;
        position: unset;
        left: 0;
        margin-bottom: auto;
        height: 64px;
        width: 100%;
        overflow: hidden;
    }

the added footer on the master page

<footer>
        <asp:Image ID="Image2" runat="server" ImageUrl="~/wp-content/Images/114x114.png" ImageAlign="Baseline"
            AlternateText="Foodora.com" Height="67px" />
        &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; &nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;
                <asp:Image ID="Image3" ImageAlign="Middle" runat="server" ImageUrl="~/wp-content/Social/facebook_sq.png" />
        &nbsp;&nbsp;&nbsp;
            <asp:Image ID="Image4" ImageAlign="Middle" runat="server" ImageUrl="~/wp-content/Social/twitter_sq.png" />
        &nbsp;&nbsp;&nbsp;
            <asp:Image ID="Image5" ImageAlign="Middle" runat="server" ImageUrl="~/wp-content/Social/instagram_sq.png" />
    </footer>

but on the page, that has a small amount of content the footer has white blank space ...

enter image description here