Can You Use `position: absolute` Without Setting `top`, `left`, `bottom`, or `right`?

Position: Absolute Without Setting Top/Left/Bottom/Right?

In CSS, the position: absolute property allows you to remove an element from the normal document flow, making it positioned absolutely relative to its container. However, sometimes you may want to use position: absolute without setting explicit values for the top, left, bottom, or right properties.

Case #1:

One scenario where this approach can be useful is when you want to position an element relative to another element within the same container. For instance, you may want to place a logo above a photo in a header, as demonstrated in the example HTML and CSS below:

<a></a>

#logo {
  position: absolute;
  margin: 10px;
  /* or padding: 10px; */
  /* or border: 10px solid transparent; */
}

In this example, setting position: absolute without specifying a top value positions the logo 10px above the photo, using the photo's top margin as a reference point.

Case #2:

Another instance where this technique might be useful is when working with table-based layouts. For example, you may want to create a horizontal multi-level menu that spans the entire width of the container. Since table cells do not support position: relative, you can use position: absolute without top/left/bottom/right values as shown below:

#menu td {
  position: absolute;
  height: 100%;
  width: 100%;
}

In this scenario, the position: absolute property without any additional values positions each cell within the table relative to the table's bounds, allowing you to create an absolute multi-level menu that aligns seamlessly.

According to CSS Standards:

Generally, the CSS specifications state that if the top/bottom or left/right properties are set to auto, they should default to the element's position: static values. However, it's important to note that browser implementations may vary in their support for absolute positioning without explicitly set top/left/bottom/right values.

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