Height is not accurate on mobile device emulator

<section class="top">  
    <header class="page-header">
        <img class="page-header__item" src="img/favicon.png" alt="logo"> 
        <nav class="main-navigation page-header__item">
            <ul role="menubar" class="navigation-list">
                <li role="presentation">
                    <a href="#about" role="menuitem" class="navigation-list__item">About</a>
                </li>
                <li role="presentation">
                    <a href="#work" role="menuitem" class="navigation-list__item" >My Work</a>
                </li>
                <li role="presentation">
                    <a href="#contact" role="menuitem" class="navigation-list__item">Contact</a>
                </li>    
            </ul>
        </nav>
    </header>

    <div class="profile">
        <p class="profile__name">My Name</p>
        <p class="profile__dev">Web Developer in Some City/p>
        <ul class="social-media">
            <li>
                <a title="Github"  href="https://github.com/">
                <img class="social-media__icon" src="img/github.png" alt="Github">
            </a>
            </li>
            <li>
                <a title="LinkedIn"  href="https://www.linkedin.com/">
                <img class="social-media__icon" src="img/linkedin.png" alt="LinkedIn">
            </a>
            </li>
        </ul>
    </div>
</section>

* {
    -webkit-box-sizing: border-box;
            box-sizing: border-box;
}

:root {
    --main-font: 'Quicksand', sans-serif;
    --second-font: 'Trispace', sans-serif;
}

html {
    scroll-behavior: smooth;
}

body {
    margin: 0;
}

html, body {
    height: 100%;
}
html,body {
    text-size-adjust: none;
    -webkit-text-size-adjust: none;
    -moz-text-size-adjust: none;
    -ms-text-size-adjust: none;
}
.page-header {
    display: -webkit-box;
    display: -ms-flexbox;
    display: flex;
    width: 100%; 
    padding-right: 1.5rem;
}

.page-header__item {
            -webkit-box-flex: 0;
                -ms-flex: 0 1 200px;
                    flex: 0 1 200px;   
}


.page-header__item:last-child {
    -webkit-box-flex: 1;
        -ms-flex-positive: 1;
            flex-grow: 1;
    text-align: right;
}
.navigation-list {
    margin-right: 1rem;
    /* margin-top: 5rem; */
    -webkit-padding-start: 0;
            padding-inline-start: 0;
}
.navigation-list li {
    margin: 1rem 0;
    font-size: 2rem;
    list-style: none;
}

.navigation-list a {
    color: white;
    font-family: 'Quicksand', sans-serif;
    text-decoration: none;
}
.navigation-list a:hover,
.navigation-list a:focus {
    text-decoration: underline; 
}

.top {
    background-image: -o-linear-gradient( rgba(8, 8, 37, 0.8), rgba(0, 15, 80, 0.625)), url("../img/pic2.jpg");
    background-image: -webkit-gradient( linear, left top, left bottom, from(rgba(8, 8, 37, 0.8)), to(rgba(0, 15, 80, 0.625))), url("../img/pic2.jpg");
    background-image: linear-gradient( rgba(8, 8, 37, 0.8), rgba(0, 15, 80, 0.625)), url("../img/pic2.jpg");
    background-size: cover;
    background-position: center;
    min-height: 900px;
    width: 100%;
    height: 100vh;
    background-attachment: fixed;
    object-fit: contain;
}
.profile {
    text-align: center;
    color: white;
}
.profile__name {
    padding-top: 12rem;
    font-size: 3rem;
    font-family: 'Quicksand', sans-serif;
}
.profile__dev {
    font-size: 2rem;
    font-family: 'Trispace', sans-serif;
}
.social-media {
    margin-top: 10rem;
    padding-bottom: 2rem;
    padding-inline-start: 0%;
}
.social-media li {
    display: inline-block;
    list-style: none;
    margin: 0 6%;
}

.social-media img {
    width: 90px;
    height: 90px;
}