Fixed width div on left, fill remaining width div on right

Question

I want a div with a fixed width image on the left and a variable width div with a background color, which should extend its width 100% on my device. I can't stop the second div from overflowing my fixed div.

When I add overflow:hidden at the variable width div it just jumps under the photo, on the next row.

How can I fix this the right way (i.e. without hacks or margin-left, since I need to make the site responsive later with media queries and I have to change the image with other resolution images for each device)?

• beginner web designer trying to tackle the horror of responsive websites -

HTML:

<div class="header"></div>
<div class="header-right"></div>

CSS:

.header{
    float:left;
    background-image: url('img/header.png');
    background-repeat: no-repeat;
    width: 240px;
    height: 100px;
    }

.header-right{
    float:left; 
    overflow:hidden; 
    background-color:#000;
    width: 100%;
    height: 100px;
    }

Answer 1

Try removing the float:left and width:100% from .header-right — the right div then behaves as requested.

.header {
  float: left;
  background: #efefef;
  background-repeat: no-repeat;
  width: 240px;
  height: 100px;
}

.header-right {
  overflow: hidden; 
  background-color: #000;
  height: 100px;
}

<div class="header"></div>
<div class="header-right"></div>