
There are four lines over the background. They are visible in overall sections but not over images.
How to make this?

There are four lines over the background. They are visible in overall sections but not over images.
How to make this?
It is as easy as this
body{
background: linear-gradient(90deg, #eee 1%, transparent 1%) 1px 0, #fff;
background-size: 200px 1px;
}
DEMO: https://codepen.io/anon/pen/VMzwNw
These and many other backgrounds can be generated using this site -> http://lea.verou.me/css3patterns/#stairs
You can use CSS linear gradients and multiple backgrounds to achieve this. Here's an example:
div {
height: 100px;
background-color: transparent;
background-size: 25% 100%;
background-repeat: repeat-x;
background-image: linear-gradient(to right, black 1px, transparent 1px);
background-position: 12.5%;
}
<div>
</div>
The gradient draws a vertical line, whereas background-size, background-position and background-repeat combined make the vertical line repeat.
Here's an example with a background image and the vertical lines:
div {
height: 100px;
background-color: transparent;
background-size: 25% 100%, cover;
background-repeat: repeat-x, no-repeat;
background-image: linear-gradient(to right, black 1px, transparent 1px), url(http://lorempixel.com/400/200/);
background-position: 12.5%, center;
}
<div>
</div>