CSS (Cascading Style Sheets) is a technology used to describe the appearance of Web documents. CSS can apply styles to different elements of an HTML document, such as fonts, colors, spacing, backgrounds, and more. It enables developers to change the appearance and layout of the page without changing the HTML structure. In this article, we will explore how to style in CSS.

1. Selector

In CSS, selectors are used to select elements to which styles are to be applied. There are several different selector types, such as:

• Tag selectors (e.g. p, h1, div, span)
• Class selectors (e.g. .red, .blue)
• ID selector (such as #header, #footer)
• Attribute selector (such as [type="text"])
• Pseudo-class selector (such as: hover ,:focus)

In order to set the style, we need to select one or more elements. This can be done with one or more selectors. For example, to select an element with class "red" you can use the following CSS code:

.red {
    color: red;
}

This will set the text color of all elements with class "red" to red.

2. Style Properties

Each selector is styled with one or more style properties. Here are some common style properties:

• color: Set the text color
• font-size: Set the font size
• font-family: Set the font type
• background-color: Set the background color
• margin: Set the outer margin of the element
• padding: Set the inner margin of the element
• border: Set the border of the element
• width: Set the width of the element
• height: Set the height of the element
• text-align: Set the text alignment

Style attributes and Attribute values ??are generally separated by colons, and attributes are separated by semicolons. For example:

p {
    font-size: 16px;
    color: #333;
    font-family: sans-serif;
}

This will set the font size of all paragraphs to 16 pixels, the color to dark gray (#333), and the font to sans serif.

3. Cascading

Cascading in CSS refers to the hierarchical effect of styles. If multiple style rules are applied to the same element, the browser will use specific rules to determine which style will be applied.

Styles can be applied to the tag, class, and ID attributes of elements. When an element has multiple style rules applied to it, CSS will use a specific hierarchy to decide which rule has the highest priority, as follows:

• ID style specifies the style (#id )
• Style specified by class style (.class)
• Style specified by element/tag (div, p, h1, etc.)
• General style (*)
• Browser default style

This is the so-called "style cascading order". First, styles are applied based on ID, and then styles of classes and elements are applied in the order they appear in the style sheet. Universal styles specify styles that apply to all elements, and browser default styles refer to the styles that the browser applies to an element by default.

4. Box model

The box model in CSS describes the layout of an HTML element. An element's box model consists of four parts: content area, padding, borders, and margins.

• Content area: text and images inside the element.
• Padding: The space between the content area and the border of the element.
• Border: The line surrounding the element.
• Margin: The space between the element's border and other elements.

The border style (such as solid line, dashed line and dotted line) and border color in CSS can be modified.

Padding and margins in CSS can be specified using pixels (px), percentages (%), and other units.

5. Conclusion

This article provides the basics of styling in CSS. Set styles by selecting elements in a selector, using style properties, and using Cascading as needed to determine the order of styles. We also learned about the CSS box model, which is the basis for element layout and appearance in CSS. When you master these basics, you will be able to use CSS to create beautiful web page layouts.

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