why is nav icon not showing? - html

<!doctype html>
<html lang="en">
<head>
<!-- Required meta tags -->
<meta charset="utf-8">
<meta name="viewport" content="width=device-width, initial-scale=1">
<!-- Bootstrap CSS -->
<link href="https://cdn.jsdelivr.net/npm/bootstrap#5.0.2/dist/css/bootstrap.min.css" rel="stylesheet"
integrity="sha384-EVSTQN3/azprG1Anm3QDgpJLIm9Nao0Yz1ztcQTwFspd3yD65VohhpuuCOmLASjC" crossorigin="anonymous">
<!-- Own Css -->
<link rel="stylesheet" href="css/style.css">
<title>Tropico</title>
</head>
<body>
<!-- Section - 1 Navigation Starts -->
<nav class="navbar navbar-expand-lg">
<div class="container">
<img src="img/logo.png" alt=""><span>Tropico</span>
<button class="navbar-toggler" type="button" data-toggle="collapse" data-target="#navmenu">
<span class="navbar-toggler-icon"></span>
</button>
<div class="collapse navbar-collapse" id="navmenu">
<ul class="navbar-nav ms-auto">
<li class="nav-item">
Home
</li>
<li class="nav-item">
Fruits
</li>
<li class="nav-item">
Services
</li>
<li class="nav-item">
Contact us
</li>
<button class="nav-item">Get a quote</button>
</ul>
</div>
</div>
</nav>
<!-- Section - 1 Navigation End -->
<script src="https://cdn.jsdelivr.net/npm/bootstrap#5.0.2/dist/js/bootstrap.bundle.min.js"
integrity="sha384-MrcW6ZMFYlzcLA8Nl+NtUVF0sA7MsXsP1UyJoMp4YLEuNSfAP+JcXn/tWtIaxVXM"
crossorigin="anonymous"></script>
</body>
</html>
Nav icon not showing when display goes below 992px as i used navbar-expand-lg in bootstrap5.
Nav icon not showing when display goes below 992px as i used navbar-expand-lg in bootstrap5
Nav icon not showing when display goes below 992px as i used navbar-expand-lg in bootstrap5
Nav icon not showing when display goes below 992px as i used navbar-expand-lg in bootstrap5
Nav icon not showing when display goes below 992px as i used navbar-expand-lg in bootstrap5
Nav icon not showing when display goes below 992px as i used navbar-expand-lg in bootstrap5

maybe your source in img tag is wrong
if you have img folder in your root path (based on src="img/logo.png") change it to <img src="/img/logo.png" alt="">
If not worked see html file paths

Since you are using Bootstrap 5.0.2, you got to do the following modification:
Add .navbar-light in <nav> to have the nav burger menu icon displayed. It's because the selector in Bootstrap to display the image is .navbar-light .navbar-toggler-icon so without .navbar-light it won't be displayed.
Spotted another issue with the interaction with this toggle icon. You'll need to do the following modifications as well:
Modify data-toggle="collapse" to data-bs-toggle="collapse"
Modify data-target="#navmenu" to data-bs-target="#navmenu"
FYI data-target was the previous annotation used in Bootstrap v4. Now, in Bootstrap v5, every data-* has been changed to data-bs-*
Don't forget to use aria-* as mentioned in Bootstrap documentation as well for accessibility :)

You have some BS missing classes
try this:
<!DOCTYPE html>
<html lang="en">
<head>
<!-- Required meta tags -->
<meta charset="utf-8">
<meta name="viewport" content="width=device-width, initial-scale=1">
<!-- Bootstrap CSS -->
<link href="https://cdn.jsdelivr.net/npm/bootstrap#5.0.2/dist/css/bootstrap.min.css" rel="stylesheet"
integrity="sha384-EVSTQN3/azprG1Anm3QDgpJLIm9Nao0Yz1ztcQTwFspd3yD65VohhpuuCOmLASjC" crossorigin="anonymous">
<!-- Own Css -->
<link rel="stylesheet" href="css/style.css">
<title>Tropico</title>
</head>
<body>
<!-- Section - 1 Navigation Starts -->
<nav class="navbar navbar-expand-sm navbar-light navbar-expand-lg">
<div class="container">
<img src="https://i.imgur.com/vhbkAUt.png" width="40" alt=""><span>Tropico</span>
<button class="navbar-toggler" type="button" data-bs-toggle="collapse" data-bs-target="#navmenu">
<span class="navbar-toggler-icon"></span>
</button>
<div class="collapse navbar-collapse" id="navmenu">
<ul class="navbar-nav ms-auto">
<li class="nav-item">
Home
</li>
<li class="nav-item">
Fruits
</li>
<li class="nav-item">
Services
</li>
<li class="nav-item">
Contact us
</li>
<button class="nav-item">Get a quote</button>
</ul>
</div>
</div>
</nav>
<!-- Section - 1 Navigation End -->
<script src="https://cdn.jsdelivr.net/npm/bootstrap#5.0.2/dist/js/bootstrap.bundle.min.js"
integrity="sha384-MrcW6ZMFYlzcLA8Nl+NtUVF0sA7MsXsP1UyJoMp4YLEuNSfAP+JcXn/tWtIaxVXM"
crossorigin="anonymous"></script>
</body>
</html>

Related

New to Bootstrap. Once Navbar has collapsed to Hamburger menu - the nav links wont drop down on click of the hamburger icon

Right so, copied the standard bootstrap navbar code from both the bootstrap and the w3schools site. everything is working fine except when the navbar has collapsed to a hamburger menu nothing is displayed on click of the hamburger icon....
Even when copied and pasted with 0 edits its not working in Chrome.
Pretty sure i've properly linked all the files bootstrap needs...
Thanks for taking the time to help me out with this.
This is my complete html code.
<!doctype html>
<html>
<head>
<meta charset="UTF-8">
<title>Untitled Document</title>
<!-- Bootstrap CSS-->
<link href="https://cdn.jsdelivr.net/npm/bootstrap#5.0.0/dist/css/bootstrap.min.css" rel="stylesheet" integrity="sha384-wEmeIV1mKuiNpC+IOBjI7aAzPcEZeedi5yW5f2yOq55WWLwNGmvvx4Um1vskeMj0" crossorigin="anonymous">
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<script src="https://cdn.jsdelivr.net/npm/#popperjs/core#2.9.2/dist/umd/popper.min.js" integrity="sha384-IQsoLXl5PILFhosVNubq5LC7Qb9DXgDA9i+tQ8Zj3iwWAwPtgFTxbJ8NT4GN1R8p" crossorigin="anonymous"></script>
<script src="https://cdn.jsdelivr.net/npm/bootstrap#5.0.0/dist/js/bootstrap.min.js" integrity="sha384-lpyLfhYuitXl2zRZ5Bn2fqnhNAKOAaM/0Kr9laMspuaMiZfGmfwRNFh8HlMy49eQ" crossorigin="anonymous"></script>
<!-- Jquery-->
<script src="jquery-3.6.0.min.js"></script>
<!--Style-->
<link href="stylesheet.css" rel="stylesheet">
<!--Java-->
<script src="java.js"></script>
</head>
<body>
<!-- Navbar-->
<nav class="navbar navbar-expand-md bg-dark navbar-dark">
<!-- Brand -->
<a class="navbar-brand" href="#">
<img src="Logo/SVG/Black Diamond - LOGO-2021_White on BG.svg" width="200">
</a>
<!-- Toggler/collapsibe Button -->
<button class="navbar-toggler" type="button" data-toggle="collapse" data-target="#collapsibleNavbar">
<span class="navbar-toggler-icon"></span>
</button>
<!-- Navbar links -->
<div class="collapse navbar-collapse" id="collapsibleNavbar">
<ul class="navbar-nav">
<li class="nav-item">
<a class="nav-link" href="#">Snowboards</a>
</li>
<li class="nav-item">
<a class="nav-link" href="#">Men</a>
</li>
<li class="nav-item">
<a class="nav-link" href="#">Women</a>
</li>
<li class="nav-item">
<a class="nav-link" href="#">Accesories</a>
</li>
</ul>
</div>
</nav>
</body>
</html>

Can't figure out how to make my collapsible navbar button not always visible (Bootstrap v.3)

I cannot figure out how to get my button for my collapsible navbar not to appear all the time. I have followed various online tutorials with almost the exact same code as mine however I am not achieving the same result.
<!DOCTYPE html>
<html lang="en">
<head>
<title>Pentakill - About</title>
<link rel="icon" href="images/pentakilllogo.ico">
<meta charset="utf-8">
<meta name="viewport" content="width=device-width, initial-scale=1, shrink-to-fit=no">
<script type="text/javascript" src="script.js"></script>
<link rel="stylesheet" href="https://maxcdn.bootstrapcdn.com/bootstrap/3.4.0/css/bootstrap.min.css">
<script src="https://ajax.googleapis.com/ajax/libs/jquery/3.4.1/jquery.min.js"></script>
<script src="https://maxcdn.bootstrapcdn.com/bootstrap/3.4.0/js/bootstrap.min.js"></script>
<link href='https://fonts.googleapis.com/css?family=Metal Mania' rel='stylesheet'>
<link rel="stylesheet" type="text/css" href="css/main.css">
</head>
<body>
<nav class="navbar navbar-expand-sm sticky-top">
<div class="container-fluid">
<div class="navbar-header">
<button type="button" class="navbar-toggler" data-toggle="collapse" data-target="#myCollapsibleNavbar">
<span class="icon-bar metal">Options</span>
</button>
<a class="navbar-brand pentaicon"><img src="images/pentakilllogo.ico"></a>
<span class="navbar-brand metal">Pentakill</span>
</div>
<div class="collapse navbar-collapse" id="myCollapsibleNavbar">
<ul class="nav navbar-nav">
<li>
<a class="metal" href="index.php">Home</a>
</li>
<li>
<a class="metal" href="about.php">About</a>
</li>
<li>
<a class="metal" href="music.php">Music</a>
</li>
<li class="active">
<a class="metal" href="tour.php">Tour</a>
</li>
<li class="nav-item">
<a class="metal" href="members.php">Members</a>
</li>
</ul>
<ul class="nav navbar-nav navbar-right">
<li><a class="metal" href="login.php"><span class="glyphicon glyphicon-user"></span>Login/Sign Up</a></li>
</ul>
</div>
</div>
</nav>
I have tried adding and removing various divs but nothing seems to make a difference.
I also tried removing the word "Options" in case that was the culprit, but with no luck.
Are you intentionally using the Bootstrap 3.4 CDN instead of the most recent version? Following along on a tutorial such as https://getbootstrap.com/docs/4.0/components/navbar/ may cause issues. I placed your code into a codepen linked to the latest version and don't see the button, just spacing issues then.

Alignment of toggle button (humberger icon) in small screen view using bootstrap 4

I am new to bootstrap and I need to use bootstrap 4 for creating a fully responsive menu. The main navigation should use bootstrap collapsible navbar to show a hamburger icon atthe smaller screen widths. I found a smaple code from w3 which gives me a menu in the right side and when I resize to small view the harmber icon (the toggle view) appears on the right side:
<!DOCTYPE html>
<html lang="en">
<!-- head includes title of page, meta data and Style links -->
<head id="head">
<title> Home page </title>
<meta charset="utf-8"/>
<!-- link to use bootstrap -->
<link rel="stylesheet" href="https://maxcdn.bootstrapcdn.com/bootstrap/4.3.1/css/bootstrap.min.css">
<script src="https://maxcdn.bootstrapcdn.com/bootstrap/4.3.1/js/bootstrap.min.js"></script>
<!-- link to reset css -->
<link rel="stylesheet" href="css/reset.css"/>
<!-- link to css folder -->
<link rel="stylesheet" href="css/style.css"/>
</head>
<body>
<header>
<nav class="navbar navbar-expand-sm navbar-dark bg-primary">
<div class="navbar-brand"></div>
<button class="navbar-toggler" type="button" data-toggle="collapse" data-target="#collapsibleNavbar">
<span class="navbar-toggler-icon"></span>
</button>
<div class="collapse navbar-collapse" id="collapsibleNavbar">
<ul class="navbar-nav ml-auto">
<li class="nav-item">
<a class="nav-link" href="#">My Account</a>
</li>
<li class="nav-item">
<a class="nav-link" href="#">Basket</a>
</li>
<li class="nav-item">
<a class="nav-link" href="#">Checkout</a>
</li>
</ul>
</div>
</nav>
</header>
<main>
</main>
<script src="https://code.jquery.com/jquery-3.3.1.slim.min.js" integrity="sha384-q8i/X+965DzO0rT7abK41JStQIAqVgRVzpbzo5smXKp4YfRvH+8abtTE1Pi6jizo" crossorigin="anonymous"></script>
<script src="https://cdnjs.cloudflare.com/ajax/libs/popper.js/1.14.7/umd/popper.min.js" integrity="sha384-UO2eT0CpHqdSJQ6hJty5KVphtPhzWj9WO1clHTMGa3JDZwrnQq4sF86dIHNDz0W1" crossorigin="anonymous"></script>
<script src="https://stackpath.bootstrapcdn.com/bootstrap/4.3.1/js/bootstrap.min.js" integrity="sha384-JjSmVgyd0p3pXB1rRibZUAYoIIy6OrQ6VrjIEaFf/nJGzIxFDsf4x0xIM+B07jRM" crossorigin="anonymous"></script>
</body>
</html>
if I remove the dummy <div class="navbar-brand"></div> just before the toggle button then in small screens view, the toggle button would jump to left rather right.
What is the proper way of setting the alignment of toggle button to right instead of left without using the dummy hacky div
<div class="navbar-brand"></div>
Thanks for your help.
Try this Jsfiddle link.
Here I have applied justify-content: flex-end !important; css rule for navbar.
.navbar {
justify-content: flex-end !important;
}
<!DOCTYPE html>
<html lang="en">
<!-- head includes title of page, meta data and Style links -->
<head id="head">
<title> Home page </title>
<meta charset="utf-8"/>
<!-- link to use bootstrap -->
<link rel="stylesheet" href="https://maxcdn.bootstrapcdn.com/bootstrap/4.3.1/css/bootstrap.min.css">
<script src="https://maxcdn.bootstrapcdn.com/bootstrap/4.3.1/js/bootstrap.min.js"></script>
<!-- link to reset css -->
<link rel="stylesheet" href="css/reset.css"/>
<!-- link to css folder -->
<link rel="stylesheet" href="css/style.css"/>
</head>
<body>
<header>
<nav class="navbar navbar-expand-sm navbar-dark bg-primary">
<!-- <div class="navbar-brand"></div> -->
<button class="navbar-toggler" type="button" data-toggle="collapse" data-target="#collapsibleNavbar">
<span class="navbar-toggler-icon"></span>
</button>
<div class="collapse navbar-collapse" id="collapsibleNavbar">
<ul class="navbar-nav ml-auto">
<li class="nav-item">
<a class="nav-link" href="#">My Account</a>
</li>
<li class="nav-item">
<a class="nav-link" href="#">Basket</a>
</li>
<li class="nav-item">
<a class="nav-link" href="#">Checkout</a>
</li>
</ul>
</div>
</nav>
</header>
<main>
</main>
<script src="https://code.jquery.com/jquery-3.3.1.slim.min.js" integrity="sha384-q8i/X+965DzO0rT7abK41JStQIAqVgRVzpbzo5smXKp4YfRvH+8abtTE1Pi6jizo" crossorigin="anonymous"></script>
<script src="https://cdnjs.cloudflare.com/ajax/libs/popper.js/1.14.7/umd/popper.min.js" integrity="sha384-UO2eT0CpHqdSJQ6hJty5KVphtPhzWj9WO1clHTMGa3JDZwrnQq4sF86dIHNDz0W1" crossorigin="anonymous"></script>
<script src="https://stackpath.bootstrapcdn.com/bootstrap/4.3.1/js/bootstrap.min.js" integrity="sha384-JjSmVgyd0p3pXB1rRibZUAYoIIy6OrQ6VrjIEaFf/nJGzIxFDsf4x0xIM+B07jRM" crossorigin="anonymous"></script>
</body>
</html>

buttons resizing on site with Bootstrap

I have been working on a site using the Download ready-to-use compiled code for Bootstrap v4.1.3 provided on the bootstrap page, and after reading how to work on the nav and the buttons I have stumbled into a problem.
below of my meta tags I have the css links
<!DOCTYPE html>
<html>
<head>
<meta charset="UTF-8">
<meta name="description" content="">
<meta http-equiv="X-UA-Compatible" content="IE=edge">
<meta name="viewport" content="width=device-width, initial-scale=1, shrink-to-fit=no">
<!-- Bootstrap CSS -->
<link rel="stylesheet" href="addons/css/bootstrap.min.css">
<link rel="stylesheet" href="addons/css/core-style.css">
<link rel="stylesheet" href="addons/css/menustyle.css">
</head>
<body>
<header>
<nav class="navbar navbar-expand-md navbar-light bg-info fixed-top">
<a class="navbar-brand" href="#">
<img src="/docs/4.1/assets/brand/bootstrap-solid.svg" width="30" height="30" class="d-inline-block align-top">
Bootstrap</a>
<div class="collapse navbar-collapse" id="navbarNavAltMarkup">
<div class="navbar-nav">
<a class="nav-item nav-link" href="#">Facultad</a>
<a class="nav-item nav-link" href="#">Alumnos</a>
<a class="nav-item nav-link active" href="#">Consultas<span class="sr-only">(current)</span></a>
</div>
<div class="mx-auto"><b><h4>Consulta General [Notas]</h4></b></div>
</div>
</nav>
</header>
<section>...<section>
<section>...<section>
<button type="button" class="btn btn-secondary" style="width:auto" onClick="window.location.href='../Consultas.html'">Menu Consultas</button>
<section>...<section>
<footer>...</footer>
<!-- Opptional JavaScript -->
<!-- jQuery first, then Popper.js, then Bootstrap JS -->
<script src="js/jquery-3.3.1.slim.min.js"></script>
<script src="js/bootstrap.min.js"></script>
</body>
</html>
The only fix I have for the button that I have in the body bellow all the other code but on the nav the code button tag does the same for the code of a tag
From the navbar the only one that has given me a problem is Placeholder that is between the atags same with the code below and that is when I hover over the button it gets smaller and that changes the height of the navbar when I hover it, link works fine and all is just that the hover, also the same happens when I use the code for the button on the Navbar provided by bootstrap
<a class="btn btn-secondary" href="Menu.php" role="button">Menu Principal</a>
the button on my code works but the a with role=button on another page does the same as the nav.
Don't know if I fully explained my issue or is easy to understand, also the code I been using is on the documentation of the Bootstrap site, also for the navbar if I don't put fixed-top on the class it leaves a white space at the top of the page I put the following code on menustyle.css but it didn't fix it, is there another way to remove the white space without the need to use fixed-top in the nav class?
header{
margin:0px;
}
body{
margin:0;
}
<!DOCTYPE html>
<html lang="en">
<head>
<link rel="stylesheet" href="https://maxcdn.bootstrapcdn.com/bootstrap/3.3.7/css/bootstrap.min.css">
<script src="https://ajax.googleapis.com/ajax/libs/jquery/3.3.1/jquery.min.js"></script>
<script src="https://maxcdn.bootstrapcdn.com/bootstrap/3.3.7/js/bootstrap.min.js"></script>
</head>
<body>
<nav class="navbar navbar-default">
<div class="container-fluid">
<div class="navbar-header">
<a class="navbar-brand" href="#">nav-bar</a>
</div>
<ul class="nav navbar-nav">
<li class="active" title="home">Home</li>
<li>Page 1</li>
<li>Page 2</li>
<li>Page 3</li>
</ul>
</div>
</nav>
</body>
</html>
Hey, this is the working snippet for nav bar . Please show us the issue which you're facing

Using Bootstrap, how do I center my navigation bar?

So I have this code below.
Using Bootstrap I would like to have this drop down on the left in the middle of the screen. https://screenshots.firefox.com/WKjwlW5eUiVdS0fO/null How would I do this?
Additional Question: How do I make the 3 lines bigger? Do I just make the navbar-toggler-icon bigger?
<html lang="en">
<head>
<!-- Required meta tags -->
<meta charset="utf-8">
<meta name="viewport" content="width=device-width, initial-scale=1, shrink-to-fit=no">
<!-- Bootstrap CSS -->
<link rel="stylesheet" type="text/css" href="css/bootstrap.css">
<!-- My CSS -->
<link rel="stylesheet" type="text/css" href="css/style.css">
</head>
<body>
<!-- Navigation Bar -->
<nav class="navbar navbar-toggleable-md navbar-light bg-faded navbar-fixed-top">
<div class="container-fluid">
<button class="navbar-toggler navbar-toggler-right" type="button" data-toggle="collapse" data-target="#navbarNav">
<span class="navbar-toggler-icon"></span>
</button>
<div class="collapse navbar-collapse" id="navbarNav">
<ul class="navbar-nav;">
<li class="nav-item active">
<a class="nav-link" href="#">Home</a>
</li>
<li class="nav-item">
<a class="nav-link" href="#">My Work</a>
</li>
<li class="nav-item">
<a class="nav-link" href="#">Contact Me</a>
</li>
</ul>
</div>
</div>
</nav>
<!-- Optional JavaScript -->
<!-- jQuery first, then Popper.js, then Bootstrap JS -->
<script src="https://code.jquery.com/jquery-3.2.1.slim.min.js" integrity="sha384-KJ3o2DKtIkvYIK3UENzmM7KCkRr/rE9/Qpg6aAZGJwFDMVNA/GpGFF93hXpG5KkN" crossorigin="anonymous"></script>
<script src="https://cdnjs.cloudflare.com/ajax/libs/popper.js/1.11.0/umd/popper.min.js" integrity="sha384-b/U6ypiBEHpOf/4+1nzFpr53nxSS+GLCkfwBdFNTxtclqqenISfwAzpKaMNFNmj4" crossorigin="anonymous"></script>
<script src="https://maxcdn.bootstrapcdn.com/bootstrap/4.0.0-beta/js/bootstrap.min.js" integrity="sha384-h0AbiXch4ZDo7tp9hKZ4TsHbi047NrKGLO3SEJAg45jXxnGIfYzk4Si90RDIqNm1" crossorigin="anonymous"></script>
</body>
</html>
Using Bootstrap I would like to have this drop down that is currently on the left... in the middle of the screen. https://screenshots.firefox.com/WKjwlW5eUiVdS0fO/null How would I do this?
Additional Question: How do I make the 3 lines bigger? Do I just make the navbar-toggler-icon bigger?
Setting the left and right margin to auto might work. Try this! mx-auto - says margin on the x-axis (ie., left and right) is set to auto!
<html lang="en">
<head>
<!-- Required meta tags -->
<meta charset="utf-8">
<meta name="viewport" content="width=device-width, initial-scale=1, shrink-to-fit=no">
<!-- Bootstrap CSS -->
<link rel="stylesheet" type="text/css" href="css/bootstrap.css">
<!-- My CSS -->
<link rel="stylesheet" type="text/css" href="css/style.css">
</head>
<body>
<!-- Navigation Bar -->
<nav class="navbar navbar-toggleable-md navbar-light bg-faded navbar-fixed-top">
<div class="container-fluid">
<button class="navbar-toggler mx-auto" type="button" data-toggle="collapse" data-target="#navbarNav">
<span class="navbar-toggler-icon"></span>
</button>
<div class="collapse navbar-collapse" id="navbarNav">
<ul class="navbar-nav;">
<li class="nav-item active">
<a class="nav-link" href="#">Home</a>
</li>
<li class="nav-item">
<a class="nav-link" href="#">My Work</a>
</li>
<li class="nav-item">
<a class="nav-link" href="#">Contact Me</a>
</li>
</ul>
</div>
</div>
</nav>
<!-- Optional JavaScript -->
<!-- jQuery first, then Popper.js, then Bootstrap JS -->
<script src="https://code.jquery.com/jquery-3.2.1.slim.min.js" integrity="sha384-KJ3o2DKtIkvYIK3UENzmM7KCkRr/rE9/Qpg6aAZGJwFDMVNA/GpGFF93hXpG5KkN" crossorigin="anonymous"></script>
<script src="https://cdnjs.cloudflare.com/ajax/libs/popper.js/1.11.0/umd/popper.min.js" integrity="sha384-b/U6ypiBEHpOf/4+1nzFpr53nxSS+GLCkfwBdFNTxtclqqenISfwAzpKaMNFNmj4" crossorigin="anonymous"></script>
<script src="https://maxcdn.bootstrapcdn.com/bootstrap/4.0.0-beta/js/bootstrap.min.js" integrity="sha384-h0AbiXch4ZDo7tp9hKZ4TsHbi047NrKGLO3SEJAg45jXxnGIfYzk4Si90RDIqNm1" crossorigin="anonymous"></script>
</body>
</html>
Hope this helps!
Bootstrap includes a flexbox grid system for building layouts. It’s based on a 12 column layout and has multiple tiers. It is basically a css class like any other. Bootstrap comes with these classes predefined.
For example:
<div class="col-lg-12">
This would take up all available screen space
</div>
Then all you have to do is center your content and you will end up with a div that takes up the area you want with content that is centered inside it.
The lg in this example stands for a large area, but there are several of these. They can be used in pairs to change the grid based on the available screen area. These col types are predefined and can be easily referenced.
Using this grid system is going to make whatever you create responsive. It is a joy to work with. I recommend you check it out.