1. Colour Background Style
   The color on a background of a widget using the syntax: # color code, and following more:

   #side-wrapper {
float: left;
margin: 0px 0px 0px 0px;
padding: 25px 0px 0px 0px;
width: 315px;
background: #ffffff;
}

   
   
   
   
   
   
   
   
   
   
   
   
   Add the red code as above on the widget you want to add a background color. For color, you can use the color code found on the page menu on this blog, or Online Tool to determine the color code, and do not forget to use the pound sign (#) before code.
2. Image Background Style
   This is the technique provides images as background in a widget on your blog. Consider the following picture:
   Well, for the installation of this style, there are some changes to the syntax. Here's more:
   

   .post-footer {
display: block;
margin: 15px 0px 25px 0px;
padding: 7px 20px 7px 20px;
text-align: left;
font: $postfooterTextFont;
color: #ffffff;
font-weight: normal;
line-height: 1.6em;
text-decoration: none;
background-image:url("https://blogger.googleusercontent.com/img/b/R29vZ2xl/AVvXsEid96US6x2s1peA4sYHNUaq8wFuTZj1NTYGQzodTkP7IDVd_anpl5_T3nVemDLsvn71FiWi4M_J1WJKprXg2k2KOcgJWMbDpq2eRSJIr31_VpBXQiLV0Gh_cEuseJBx8DeY_-V5ZD4Uu-4/s1600/banner+demomaskolis.jpg");
background-color:#0092dd;
background-position:top right;
background-repeat:no-repeat;
border: 1px solid $postfooterBorderColor;
}

   
   
   
   
   
   
   
   
   
   
   
   
   
   
   
   
   
   
   
   
   
   
   
   
   
   
   
   
   
   
   
   
   
   Description:
   • Background Image URL filled image.
   • Background Color filled color coded in accordance with the drawings.
   • Position filled with background image placement position. example :
    top-left, bottom-left, top-right, bottom-right, center-right, center-left. Background Repeat filled to the side where the image will be repeated. For up, use repeat-y to: background-repeat: repeat-y; For sideways, use repeat-x to: background-repeat: repeat-x; And if you do not want repeated use no-repeat as early examples.

#main .widget {
margin: 0px 0px 0px 0px;
padding: 0px 25px 20px 25px;
}

#sidebar .widget {
margin: 0px;
padding: 0px;
}

#main .widget {
margin: 0px 0px 0px 0px;
padding: 0px 25px 20px 25px;
}

#main .widget:hover {
background:#e3e3e3;
}