Por padrão, as páginas bootstrap têm uma cor de fundo branca (clara).
Se quiser mudar a página inteira para uma cor mais escura, você pode adicionar data-bs-theme="dark" ao Elemento ><html>:
Some lorem ipsum text.
Experimente você mesmo →
<!DOCTYPE html>
<html lang="en">
<head>
<title>Bootstrap Example</title>
<meta charset="utf-8">
<meta name="viewport" content="width=device-width, initial-scale=1">
<link href="https://cdn.jsdelivr.net/npm/bootstrap@5.3.3/dist/css/bootstrap.min.css" rel="stylesheet">
<script src="https://cdn.jsdelivr.net/npm/bootstrap@5.3.3/dist/js/bootstrap.bundle.min.js"></script>
</head>
<body>
<div class="container mt-3">
<h1>My Page</h1>
<p>Lorem ipsum text.</p>
<div class="card">
<div class="card-body">A card.</div>
</div>
<p>Some buttons:</p>
<button type="button" class="btn btn-primary">Primary</button>
<button type="button" class="btn btn-secondary">Secondary</button>
<button type="button" class="btn btn-success">Success</button>
</div>
</body>
</html>
Some lorem ipsum text.
Experimente você mesmo →
<!DOCTYPE html>
<html lang="en" data-bs-theme="dark">
<head>
<title>Bootstrap Example</title>
<meta charset="utf-8">
<meta name="viewport" content="width=device-width, initial-scale=1">
<link href="https://cdn.jsdelivr.net/npm/bootstrap@5.3.3/dist/css/bootstrap.min.css" rel="stylesheet">
<script src="https://cdn.jsdelivr.net/npm/bootstrap@5.3.3/dist/js/bootstrap.bundle.min.js"></script>
</head>
<body>
<div class="container mt-3">
<h1>My Page</h1>
<p>Lorem ipsum text.</p>
<div class="card">
<div class="card-body">A card.</div>
</div>
<p>Some buttons:</p>
<button type="button" class="btn btn-primary">Primary</button>
<button type="button" class="btn btn-secondary">Secondary</button>
<button type="button" class="btn btn-success">Success</button>
</div>
</body>
</html>
Se você não deseja que a página inteira tenha uma cor mais escura, mas apenas componentes específicos, você pode adicionar o atributo data-bs-theme="dark" ao componente especificado.
Por exemplo, adicione o modo escuro a uma mesa:
<table class="table" data-bs-theme="dark">Experimente você mesmo →
<!DOCTYPE html>
<html lang="en">
<head>
<title>Bootstrap Example</title>
<meta charset="utf-8">
<meta name="viewport" content="width=device-width, initial-scale=1">
<link href="https://cdn.jsdelivr.net/npm/bootstrap@5.3.3/dist/css/bootstrap.min.css" rel="stylesheet">
<script src="https://cdn.jsdelivr.net/npm/bootstrap@5.3.3/dist/js/bootstrap.bundle.min.js"></script>
</head>
<body>
<div class="container mt-3">
<h2>Dark Mode Table</h2>
<table class="table" data-bs-theme="dark">
<thead>
<tr>
<th>Firstname</th>
<th>Lastname</th>
<th>Email</th>
</tr>
</thead>
<tbody>
<tr>
<td>John</td>
<td>Doe</td>
<td>john@example.com</td>
</tr>
<tr>
<td>Mary</td>
<td>Moe</td>
<td>mary@example.com</td>
</tr>
<tr>
<td>July</td>
<td>Dooley</td>
<td>july@example.com</td>
</tr>
</tbody>
</table>
</div>
</body>
</html>
Ou, por exemplo, adicione o modo escuro a um menu suspenso:
<div class="dropdown" data-bs-theme="dark">Experimente você mesmo →
<!DOCTYPE html>
<html lang="en">
<head>
<title>Bootstrap Example</title>
<meta charset="utf-8">
<meta name="viewport" content="width=device-width, initial-scale=1">
<link href="https://cdn.jsdelivr.net/npm/bootstrap@5.3.3/dist/css/bootstrap.min.css" rel="stylesheet">
<script src="https://cdn.jsdelivr.net/npm/bootstrap@5.3.3/dist/js/bootstrap.bundle.min.js"></script>
</head>
<body>
<div class="container mt-3">
<h2>Dark Mode Dropdown</h2>
<p>Click on the dropdown menu to see the effect.</p>
<div class="dropdown" data-bs-theme="dark">
<button type="button" class="btn btn-primary dropdown-toggle" data-bs-toggle="dropdown">
Dropdown button
</button>
<ul class="dropdown-menu">
<li><a class="dropdown-item" href="#">Link 1</a></li>
<li><a class="dropdown-item" href="#">Link 2</a></li>
<li><a class="dropdown-item" href="#">Link 3</a></li>
</ul>
</div>
</div>
</body>
</html>