CSS (Cascading Style Sheets) is used to control the presentation of HTML elements on a web page. It allows developers to separate content from design, making websites more maintainable, consistent, and visually appealing.
With CSS, you can define colors, fonts, spacing, layouts, and even animations. Understanding CSS is essential for professional web development, as it transforms plain HTML into a polished, interactive site.
CSS selectors target specific HTML elements to apply styling. Examples include element selectors, class selectors, ID selectors, and pseudo-classes. Properties define how elements appear, such as color, font-size, margin, and padding.
/* Element selector */
p {
color: #333;
font-size: 16px;
}
/* Class selector */
.highlight {
background-color: yellow;
}
/* ID selector */
#main-header {
font-weight: bold;
}Using proper selectors ensures clean, maintainable CSS and avoids conflicts.
CSS allows you to style text, layout pages, and create interactive effects. Below are a few practical examples:
/* Styling a navigation menu */
nav a {
text-decoration: none;
color: white;
padding: 10px 15px;
display: inline-block;
}
nav a:hover {
background-color: #575757;
}
/* Centering content */
.container {
max-width: 900px;
margin: 0 auto;
padding: 20px;
}Combining these techniques creates a professional, user-friendly interface.
CSS makes it possible to build responsive websites that adapt to different screen sizes. Using media queries, flexbox, and grid layouts ensures your site looks great on desktops, tablets, and mobile devices.
@media (max-width: 768px) {
.container {
padding: 10px;
}
nav {
flex-direction: column;
}
}Testing on multiple devices prevents layout issues and improves user experience.
Following best practices ensures your CSS is efficient, scalable, and easier to maintain.
CSS is a critical skill for any web developer. Mastering selectors, properties, responsive design, and best practices allows you to create visually appealing, professional websites that provide a great user experience.