When it comes to designing a website, one of the most important aspects to consider is the layout. And when we talk about layout, CSS plays a crucial role. CSS, or Cascading Style Sheets, is a language used for styling web pages. It allows web developers to control the look and feel of a website, making it visually appealing and user-friendly.
One common challenge that web developers face is determining the width of elements on a web page. While setting a fixed width is easy, setting a width that fills a percentage of the remaining area can be a bit tricky. In this article, we will discuss how to set CSS width to fill a percentage of the remaining area.
Firstly, let's understand the box model in CSS. The box model is a concept that describes how elements are laid out on a web page. It consists of four parts: content, padding, border, and margin. The content is the actual content of the element, the padding is the space between the content and the border, the border is the edge of the element, and the margin is the space between the border and other elements on the page.
Now, let's say we have a div element with a class name "box." We want this div to fill 50% of the remaining area on the page. To achieve this, we need to use the calc() function in CSS. The calc() function allows us to perform calculations to determine the value of a CSS property. In this case, we will be using it to calculate the width of the div element.
The syntax for using calc() is as follows:
width: calc(expression);
In our case, the expression will be 50% - (padding + border + margin). Let's assume our padding and border are 10px each, and the margin is 20px. So, our expression will be:
width: calc(50% - (10px + 10px + 20px));
This will make our div fill 50% of the remaining area on the page, taking into account the padding, border, and margin.
But what if we want the div to fill a specific percentage of the remaining area, say 75%? In that case, we can use the CSS property flex. Flex is a powerful CSS property that allows us to create flexible layouts. We can use it to specify the width of elements in a flexible manner.
To use flex, we need to first set the display property of the parent element to flex. This will create a flex container. Then, we can use the flex property to specify the width of the elements inside the container. The syntax for using flex is as follows:
display: flex;
flex: 1;
In the above example, we have set the width to 1, which will make the element fill the remaining space in the container. We can also use the flex property to specify the width in percentages. For example, if we want the element to fill 75% of the remaining space, we can use the following code:
display: flex;
flex: 0 0 75%;
The first value in the flex property specifies the flex-grow value, which determines how much the element can grow in relation to other elements. The second value, flex-shrink, determines how much the element can shrink in relation to other elements. The third value, flex-basis, specifies the initial width of the element. In our case, we have
