Прошу помощи с css⁠⁠

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<html lang="en">

<head>

<link rel="stylesheet" href="https://cdn.jsdelivr.net/npm/bootstrap@4.5.3/dist/css/bootstrap.min.css" integrity="sha384-TX8t27EcRE3e/ihU7zmQxVncDAy5uIKz4rEkgIXeMed4M0jlfIDPvg6uqKI2xXr2" crossorigin="anonymous">

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<link href="styles.css" rel="stylesheet">

<title>My Webpage</title>

</head>

<body>

<nav class="navbar navbar-expand-lg navbar-dark bg-dark">

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

<button class="navbar-toggler" type="button" data-toggle="collapse" data-target="#navbarSupportedContent" aria-controls="navbarSupportedContent" aria-expanded="false" aria-label="Toggle navigation">

<span class="navbar-toggler-icon"></span>

</button>

<div class="collapse navbar-collapse" id="navbarSupportedContent">

<ul class="navbar-nav mr-auto">

<li class="nav-item active">

<a class="nav-link" href="#">· 🌱 Домой 🌱 ·<span class="sr-only">(current)</span></a>

</li>

<li class="nav-item">

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

</li>

<li class="nav-item dropdown">

<a class="nav-link dropdown-toggle" href="#" id="navbarDropdown" role="button" data-toggle="dropdown" aria-haspopup="true" aria-expanded="false">

Какой то список

</a>

<div class="dropdown-menu" aria-labelledby="navbarDropdown">

<a class="dropdown-item" href="#">Действие</a>

<a class="dropdown-item" href="#">Другое действие</a>

<div class="dropdown-divider"></div>

<a class="dropdown-item" href="#">Еще какое то</a>

</div>

</li>

<li class="nav-item">

<a class="nav-link disabled" href="#">А ты сколько уже стихов написал?</a>

</li>

</ul>

<form class="form-inline my-2 my-lg-0">

<input class="form-control mr-sm-2" type="search" placeholder="Поиск" aria-label="Search">

<button class="btn btn-outline-success my-2 my-sm-0" type="submit">Найти стих</button>

</form>

</div>

</nav>

<div class="parent">

<img class="image1 wrapper exmpl" src="Gena.jpg"/>

<img class="image2" src="trololo.png"/>

<div class="gena size">

<strong class="text-white bg-dark">Евгений Пасечник</strong>

<span class="line"></span>

<blockquote class="blockquote">

<strong>

<p class="mb-0 text-white bg-dark">Lorem ipsum dolor sit amet, consectetur adipiscing elit. Integer posuere erat a ante.</p>

</strong>

</blockquote>

</div>

</div>

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<div class="video">

<iframe width="500" height="300" src="https://www.youtube.com/embed/WvC4F4Q-AeM" title="YouTube video player" frameborder="0" allow="accelerometer; autoplay; clipboard-write; encrypted-media; gyroscope; picture-in-picture" allowfullscreen></iframe>

</div>

</section>

<br>

<section class="main2">

<div class="textnormal">

<h3><strong>功夫 [gōngfu] a way to self-mastery</strong></h3>

<i><b>"There are two mistakes along the way to Self-Mastery: <br>Not starting it and not going all the way."</i></b><br> Start your personal training with guided online instructions and <br>slowly work your way towards your own destiny.

</div>

</section>

<section class="main3">

<div class="textleft">

<h3><strong>功夫 [gōngfu] a way to self-mastery</strong></h3>

<i><b>"There are two mistakes along the way to Self-Mastery: <br>Not starting it and not going all the way."</i></b><br> Start your personal training with guided online instructions and <br>slowly work your way towards your own destiny.

</div>

</section>

<br>

<section class="main4">

<div class="videoright">

<iframe width="500" height="300" src="https://www.youtube.com/embed/WvC4F4Q-AeM" title="YouTube video player" frameborder="0" allow="accelerometer; autoplay; clipboard-write; encrypted-media; gyroscope; picture-in-picture" allowfullscreen></iframe>

</div>

<section class="main5">

<div class="video">

<iframe width="500" height="300" src="https://www.youtube.com/embed/WvC4F4Q-AeM" title="YouTube video player" frameborder="0" allow="accelerometer; autoplay; clipboard-write; encrypted-media; gyroscope; picture-in-picture" allowfullscreen></iframe>

</div>

</section>

<br>

<section class="main6">

<div class="textnormal">

<h3><strong>功夫 [gōngfu] a way to self-mastery</strong></h3>

<i><b>"There are two mistakes along the way to Self-Mastery: <br>Not starting it and not going all the way."</i></b><br> Start your personal training with guided online instructions and <br>slowly work your way towards your own destiny.

</div>

</section>

<div class="maincenter">

<br>

<h3 style="text-align:center;"><strong>"Don't wait any longer. Now is your time." ⏱ </strong></h3>

<p class="textcenter">

Everything I have learned in 33 years of practice will emerge throughout all the videos. Everything I considered to be useful, I have shared on this site. There is nothing more to add at this moment. Nothing more to say, then what has been said 😶 Below you will find a 4-Step Online Training Recommendation with the chronological order of what / when and how to practice. Please take a look at this recommendation first, before you start.

<br><br>

<button type="button" class="btn btn-dark btn-lg">View recommendation</button>

</div>

<section class="main7">

<div class="textleft">

<h3><strong>功夫 [gōngfu] a way to self-mastery</strong></h3>

<i><b>"There are two mistakes along the way to Self-Mastery: <br>Not starting it and not going all the way."</i></b><br> Start your personal training with guided online instructions and <br>slowly work your way towards your own destiny.

</div>

</section>

<br>

<section class="main8">

<div class="videoright">

<iframe width="500" height="300" src="https://www.youtube.com/embed/WvC4F4Q-AeM" title="YouTube video player" frameborder="0" allow="accelerometer; autoplay; clipboard-write; encrypted-media; gyroscope; picture-in-picture" allowfullscreen></iframe>

</div>

<section class="main9">

<div class="video">

<iframe width="500" height="300" src="https://www.youtube.com/embed/WvC4F4Q-AeM" title="YouTube video player" frameborder="0" allow="accelerometer; autoplay; clipboard-write; encrypted-media; gyroscope; picture-in-picture" allowfullscreen></iframe>

</div>

</section>

<br>

<section class="main10">

<div class="textnormal">

<h3><strong>功夫 [gōngfu] a way to self-mastery</strong></h3>

<i><b>"There are two mistakes along the way to Self-Mastery: <br>Not starting it and not going all the way."</i></b><br> Start your personal training with guided online instructions and <br>slowly work your way towards your own destiny.

<br><br><br>

<blockquote style="text-align:right;" class="blockquote">

<p class="mb-0">Добро пожаловать, ценители поэзии!</p>

<footer class="blockquote-footer">Евгений Пасечник</footer>

</blockquote>

</div>

</section>

<section class="mail">

<img src="hhh.jpg"/>

<section class="pochta">

<form>

<input id="name" type="text">

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</form>

</section>

<div class="mailtext">

<h3><strong>[newsletter]</strong></h3>

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Receive new updates, course announcements, training tips /-possibilities, Retreat dates and more by joining the newsletter subscription.

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