The "bootstrap.css" uses to create a website with pre-existing designs and context. It uses basic Bootstrap classes like rows and columns with a CSS styling tool. The website is styled by importing the CSS link from the bootstrap website.

The "bootstrap.css" creates simple websites, whereas the "bootstrap-theme.css creates eye-catchy websites.

The "bootstrap-theme.css" uses to provide user interface components to a website, such as a navbar, buttons, and a progress bar. The user interface component adds to the code by invoking class attributes. The Bootstrap-theme.css file is also used to format text in various styles.

Bootstrap.css

Bootstrap is a front-end development CSS framework. Bootstrap does not permit users to write code from scratch. Instead, the user constructs user interface components using specified terminology and logic written in HTML, CSS, and JavaScript.

Bootstrap is a lightweight, free, open-source framework for creating responsive and mobile-friendly web projects. Bootstrap is a public content delivery network that allows users to remotely load CSS, JS, and pictures from its server.

Features

The following functionality includes in Bootstrap CDN:

We may begin utilizing Bootstrap because it is simple and requires only a basic understanding of HTML.
Simple integration: Bootstrap can be easily connected with several other platforms and frameworks on existing and new sites. We can also use certain Bootstrap elements in conjunction with your current CSS.
Excellent Grid System: Bootstrap is based on 12-column grids, layouts, and responsive components. It merely takes a few tweaks to switch between a fixed grid and a responsive grid.

Issues with the Bootstrap.css

The following drawbacks include in the Bootstrap.css:

When designing a website, there is a lot of overriding of files.
The JS file links to jquery and is one of the most often used libraries, but most plug-ins are inactive. If we don't want most web pages to appear the same, we need to spend a little more time designing a design.

Example

The following is an example of separating a webpage into three columns using the bootstrap directly without generating new methods.

<!DOCTYPE html>

<html>

<head>

<link rel = "stylesheet" href=

"https://stackpath.bootstrapcdn.com/bootstrap/4.4.1/css/bootstrap.min.css"

Integrity =

"sha384-Vkoo8x4CGsO3+Hhxv8T/Q5PaXtkKtu6ug5TOeNV6gBiFeWPGFN9MuhOf23Q9Ifjh"

crossorigin = "anonymous">

</head>

<body>

<br>

<div class = "container" style = "border:1px solid black;">

<div class = "row">

<div class = "col-sm">

First bootstrap.css columns

</div>

<div class = "col-sm">

Second bootstrap.css columns

</div>

<div class = "col-sm">

Third bootstrap.css columns

</div>

<div class = "col-sm">

Fourth bootstrap.css columns

</div>

</div>

</div>

</body>

</html>

Output

The following image shows the basic columns of the above bootstrap.css example.

Bootstrap-theme.css

Bootstrap-theme is a collection of HTML, CSS, and JavaScript. The Bootstrap-theme theme includes the style, page layouts, and UI components for usage in a web project. A navbar, buttons, panels, a dropdown menu, and a progress bar are all included with the Bootstrap theme.

Features

The following features are included in the Bootstrap-theme:

The bootstrap-theme features buttons, a dropdown menu, a navigation bar, a progress bar, and panels.
Classes enable us to access certain CSS and JS elements using class selectors.
The default classes in buttons save a lot of work and can be customized.
The themes are used to set the grid's height and the background color of the web page with various style formatting.
The padding of the grid for text width and height adjusts easily.
Container-fluid is used to create fluid layouts that use the entire width of the viewport across all devices.

Issues with the Bootstrap-theme.css

The following drawbacks include in the Bootstrap-theme.css:

The phrases should be remembered while writing the code. We should reread the code to ensure that we get the correct output.
Specify each phrase for website styling.

Example

The following is an example of a webpage into three columns, navbar and footer using the bootstrap classes.

<!DOCTYPE html>

<html lang="en">

<head>

<title> Bootstrap 4 navbar Example </title>

<meta charset = "utf-8">

<meta name = "viewport" content="width=device-width, initial-scale=1">

<link rel="stylesheet" href="https://cdn.jsdelivr.net/npm/[email protected]/dist/css/bootstrap.min.css">

<script src = "https://cdn.jsdelivr.net/npm/[email protected]/dist/jquery.slim.min.js">

</script>

<script src = "https://cdn.jsdelivr.net/npm/[email protected]/dist/umd/popper.min.js">

</script>

<script src = "https://cdn.jsdelivr.net/npm/[email protected]/dist/js/bootstrap.bundle.min.js">

</script>

<style>

</style>

</head>

<body>

<div class="container w-50">

<div class="container " style=" border-style: groove;">

<nav class = "navbar navbar-expand-md bg-secondary navbar-dark">

<a class = "navbar-brand" id = "brand" href="#"> JTP </a>

<ul class = "navbar-nav" id="links">

<li class = "nav-item" id="link1">

<a class = "nav-link" href="#"> First Link </a>

</li>

<li class = "nav-item" id="link2">

<a class = "nav-link" href="#"> Second Link </a>

</li>

<li class = "nav-item dropdown"  id="link3">

<a class = "nav-link dropdown-toggle" href = "#" data-toggle = "dropdown"> More Links </a>

<div class = "dropdown-menu bg-light" style = "border:1px solid black;" >

<a class = "dropdown-item" id = "items" href = "#">Item 1</a>

<a class = "dropdown-item" id="items" href = "#">Item 2</a>

</li>

</ul>

<form class = "form-inline" id ="forms" action="">

<input class = "form-control mr-sm-2" type="text" name = "search" placeholder="User Search">

<button class = "btn btn-primary" type="submit"> Search </button>

</form>

</nav>

<br>

<div class = "container-fluid">

<h3> Bootstrap Example </h3>

<p> Bootstrap-theme.css includes branding, navigation, and other features, as well as compatibility for our collapse plugin. </p>

</div>

</div>

<br>

<div class="container text-center" style = " border-style: groove;" >

<h4 style = "color:blue;"> Welcome To TutorialAndExample </h4>

<br>

<div class = "row">

<div class = "col-md-4" style = " border-style: groove;">

<p>First Column Project</p>

</div>

<div class = "col-md-4" style = " border-style: groove;">

<p> Second COlumn Project </p>

</div>

<div class = "col-md-4" style = " border-style: groove;">

<div class = "p1" style = " border-style: groove;">

<p> Third column part1 </p>

</div>

<div class = "p1" style = " border-style: groove;">

<p> Third column part2 </p>

</div>

</div>

</div>

</div>

<br>

<footer class = "container text-center"style = " border-style: groove;">

<p>JTP @2022</p>

</footer>

</div>

</body>

</html>

Output

Conclusion

The bootstrap.css and bootstrap-theme.css are part of the bootstrap framework with their features. The bootstrap.css provides basic features and functionality, whereas bootstrap-theme.css provides basic features with advanced functionality and classes. Both functions use to create user-friendly websites and web applications.

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