To create section style, you need to use theme.css
To set the width of section wrapper to 100%, you need to use below mentioned classes as per the details provided.
<div class="breadcrumb-1">
<div class="container">
<h1 class="text-left"><!-- Your Titile goes here --></h1>
<div class="breadcrumb-1-link">
<a href="#">Home</a> /
<a href="#">Elements</a> /
<a href="#" class="active">Breadcrumb</a>
</div>
</div>
</div>
<div class="breadcrumb-2">
<div class="container">
<h1 class="text-left"><!-- Your Titile goes here --></h1>
<div class="breadcrumb-2-link">
<a href="#">Home</a> /
<a href="#">Elements</a> /
<a href="#" class="active">Breadcrumb</a>
</div>
</div>
</div>
<div class="breadcrumb-3">
<div class="container">
<h1 class="text-left"><!-- Your Titile goes here --></h1>
<div class="breadcrumb-3-link">
<a href="#">Home</a> /
<a href="#">Elements</a> /
<a href="#" class="active">Breadcrumb</a>
</div>
</div>
</div>
<div class="breadcrumb-4">
<div class="container">
<h1 class="text-left"><!-- Your Titile goes here --></h1>
<div class="breadcrumb-4-link">
<a href="#">Home</a> /
<a href="#">Elements</a> /
<a href="#" class="active">Breadcrumb</a>
</div>
</div>
</div>
<div class="breadcrumb-5">
<div class="container">
<h1 class="text-left"><!-- Your Titile goes here --></h1>
<div class="breadcrumb-5-link">
<a href="#">Home</a> /
<a href="#">Elements</a> /
<a href="#" class="active">Breadcrumb</a>
</div>
</div>
</div>
<div class="breadcrumb-6">
<div class="container">
<h1 class="text-left"><!-- Your Titile goes here --></h1>
<div class="breadcrumb-6-link">
<a href="#">Home</a> /
<a href="#">Elements</a> /
<a href="#" class="active">Breadcrumb</a>
</div>
</div>
</div>
<div class="breadcrumb-7">
<div class="container">
<h1 class="text-left"><!-- Your Titile goes here --></h1>
<div class="breadcrumb-7-link">
<a href="#">Home</a> /
<a href="#">Elements</a> /
<a href="#" class="bc-link7">Breadcrumb</a>
</div>
</div>
</div>
<div class="breadcrumb-8">
<div class="container">
<h1 class="text-left"><!-- Your Titile goes here --></h1>
<div class="breadcrumb-8-link">
<a href="#">Home</a> /
<a href="#">Elements</a> /
<a href="#" class="bc-link8">Breadcrumb</a>
</div>
</div>
</div>
<div class="breadcrumb-9">
<div class="container">
<h1 class="text-left"><!-- Your Titile goes here --></h1>
<div class="breadcrumb-9-link">
<a href="#">Home</a> /
<a href="#">Elements</a> /
<a href="#" class="bc-link9">Breadcrumb</a>
</div>
</div>
</div>