style.css

* {
    box-sizing: border-box;
}

html {
    font-family: 'Roboto', sans-serif;
    scroll-behavior: smooth;
    font-size: 16px;
}

body {
    margin: 0;
    background-color: #FFFFFF;
    background-image: url("data:image/svg+xml,%3Csvg width='100' height='100' viewBox='0 0 100 100' xmlns='http://www.w3.org/2000/svg'%3E%3Cpath d='M11 18c3.866 0 7-3.134 7-7s-3.134-7-7-7-7 3.134-7 7 3.134 7 7 7zm48 25c3.866 0 7-3.134 7-7s-3.134-7-7-7-7 3.134-7 7 3.134 7 7 7zm-43-7c1.657 0 3-1.343 3-3s-1.343-3-3-3-3 1.343-3 3 1.343 3 3 3zm63 31c1.657 0 3-1.343 3-3s-1.343-3-3-3-3 1.343-3 3 1.343 3 3 3zM34 90c1.657 0 3-1.343 3-3s-1.343-3-3-3-3 1.343-3 3 1.343 3 3 3zm56-76c1.657 0 3-1.343 3-3s-1.343-3-3-3-3 1.343-3 3 1.343 3 3 3zM12 86c2.21 0 4-1.79 4-4s-1.79-4-4-4-4 1.79-4 4 1.79 4 4 4zm28-65c2.21 0 4-1.79 4-4s-1.79-4-4-4-4 1.79-4 4 1.79 4 4 4zm23-11c2.76 0 5-2.24 5-5s-2.24-5-5-5-5 2.24-5 5 2.24 5 5 5zm-6 60c2.21 0 4-1.79 4-4s-1.79-4-4-4-4 1.79-4 4 1.79 4 4 4zm29 22c2.76 0 5-2.24 5-5s-2.24-5-5-5-5 2.24-5 5 2.24 5 5 5zM32 63c2.76 0 5-2.24 5-5s-2.24-5-5-5-5 2.24-5 5 2.24 5 5 5zm57-13c2.76 0 5-2.24 5-5s-2.24-5-5-5-5 2.24-5 5 2.24 5 5 5zm-9-21c1.105 0 2-.895 2-2s-.895-2-2-2-2 .895-2 2 .895 2 2 2zM60 91c1.105 0 2-.895 2-2s-.895-2-2-2-2 .895-2 2 .895 2 2 2zM35 41c1.105 0 2-.895 2-2s-.895-2-2-2-2 .895-2 2 .895 2 2 2zM12 60c1.105 0 2-.895 2-2s-.895-2-2-2-2 .895-2 2 .895 2 2 2z' fill='%239C92AC' fill-opacity='0.14' fill-rule='evenodd'/%3E%3C/svg%3E");
}

a {
    text-decoration: none;
}

.title_logo {
    font-size: 3rem;
    font-family: 'Mouse Memoirs', sans-serif;
    color: #FFFFFF;
    background-color: #7351E2;
    border-radius: 10px;
    padding: 10px;

    border-right: 7px solid #4821C6;
    border-bottom: 7px solid #4821C6;
    top: 0;
    left: 0;
    right: -30px;
    bottom: -30px;
    margin: 10px 30px;
}

header {
    background-color: #A893ED;
}

.nav_button {
    color: #FFFFFF;
    border-radius: 10px;
    padding: 5px;
    background-color: #7351E2;
    border-right: 4px solid #4821C6;
    border-bottom: 4px solid #4821C6;
    top: 0;
    left: 0;
    right: -30px;
    bottom: -30px;
    font-family: 'Mouse Memoirs', sans-serif;
}

.nav_button:hover {
    background-color: #8567E6;
    border: 1px solid #4821C6;
    transition: background-color 0.4s, border-right 0.4s, border-bottom 0.4s, border 0.4s;
}

.nav_bar {
    position: absolute;
    padding: 30px 20px 5px 20px;
    font-family: 'Roboto', sans-serif;
    font-size: 1.5rem;
    text-decoration: none;
}

.title_block {
    display: flex;
    flex-direction: column;
    align-items: center;
    border-bottom: solid #4821C6 5px;
}

.title_logo {
    font-size: 5rem;
}

.title_subheading {
    font-weight: bold;
}

.diary_container {
    display: flex;
    flex-direction: column;
    align-items: center;
}

.date_text {
    font-size: 2rem;
    border-bottom: 1px #000000 solid;
    text-align: center;
    margin: 10px 0;
}

.weight_added_span {
    font-weight: 100;
}

.date_container {
    border: #000000 solid 1px;
    margin: 10px;
    padding: 0 20px 20px 20px;
    width: 500px;
    border-radius: 40px;
    background-color: #E9E3F4;
}

.form_box {
    display: flex;
    flex-direction: column;
    align-items: center;
    margin: 10px 150px;
    border: #000000 solid 1px;
    padding: 10px;
    width: 500px;
    border-radius: 40px;
    background-color: #E9E3F4;
}

.form_container {
    display: flex;
    flex-direction: column;
    align-items: center;
}

.back_button_container {
    display: flex;
    flex-direction: column;
    align-items: center;
}

.back_button {
    margin: 200px 0;
    color: #000000;
    border: #000000 solid 1px;
    padding: 10px;
    border-radius: 10px;
}

.back_button:hover {
    background-color: #A893ED;
    transition: background-color 0.4s, color 0.4s;
}

.comments_label {
    display: none;
}

@media screen and (max-width: 700px) {
    .nav_bar {
        position: static;
    }

    .date_container {
        max-width: 300px;
    }

    .form_box {
        max-width: 400px;
    }

    html {
        font-size: 12px;
    }

    main {
        padding: 0 10px;
    }
}