my-portfolio/src/css/main.css

/******** Imports ********/
@import "/node_modules/normalize.css/normalize.css";
@import url('https://fonts.googleapis.com/css2?family=Noto+Sans:ital,wght@0,400;0,700;1,400;1,700&family=Share+Tech+Mono&family=Source+Sans+Pro:ital,wght@0,200;0,300;0,400;0,600;0,700;0,900;1,200;1,300;1,400;1,600;1,700;1,900&display=swap');

/****** Root Style ******/
:root {
    /* colours */
    --primaryDefault: hsla(79, 62%, 51%, 1);
    --primaryHover: hsla(79, 75%, 41%, 1);
    --errorDefault: hsla(0, 62%, 51%, 1);
    --grey: hsla(0, 0%, 39%, 1);
    --mutedGrey: hsla(0, 0%, 67%, 0.58);
    --mutedBlack: hsla(0, 0%, 0%, 0.25);
    --navBack: hsl(0, 0%, 30%);

    /* font sizes */
    --titleFS: 2.25rem;
    --generalFS: 1.125rem;
    --headingFS: 1.5rem;
}

/*** Template Styles ****/

html {
    scroll-behavior: smooth;
}

a:visited {
    color: inherit;
}

h1, nav {
    font-family: Share Tech Mono, monospace;
    font-style: normal;
    font-weight: normal;
    font-size: 2.25rem;
    line-height: 2.5625rem;
    text-transform: lowercase;
}

h2 {
    font-family: Noto Sans KR, sans-serif;
    font-style: normal;
    font-weight: 500;
    font-size: 1.5rem;
    line-height: 2.1875rem;
}

a.btn, form input[type="submit"] {
    text-decoration: none;
    display: inline-block;
    padding: 1rem 2rem;
    border-radius: 0.625em;
    border: 0.3215em solid var(--primaryDefault);
    color: #FFFFFF;
}

a.btn:hover {
    border: 0.3215em solid var(--primaryHover);
}

a.btnPrimary, form input[type="submit"] {
    background: var(--primaryDefault);
    cursor: pointer;
}

a.btnOutline {
    background: #FFFFFF;
    color: var(--primaryDefault);
}

a.btnPrimary:hover, form input[type="submit"]:hover {
    background: var(--primaryHover);

}

a.btn:active, form input[type="submit"]:active {
    padding: 0.8rem 1.8rem;
}

.boxShadowOut:hover {
    box-shadow: 0 6px 4px 0 var(--mutedBlack);
}

.boxShadowIn:active {
    box-shadow: inset 0 6px 4px 0 var(--mutedBlack);
}

.textShadow:hover {
    text-shadow: 0 6px 4px var(--mutedBlack);
}

/*** Standard Styles ****/

body {
    font-family: Noto Sans KR, sans-serif;
    font-style: normal;
    font-weight: 500;
    font-size: 1.125rem;
    line-height: 1.625rem;
}

header {
    background: #6A6A6A url("../imgs/hero.jpg") no-repeat bottom;
    background-size: cover;
    height: 40%;
    color:  #FFFFFF;
    backdrop-filter: grayscale(100%);
    position: relative;
}

nav {
    display: flex;
    flex-direction: row;
    justify-content: space-between;
    padding: 0.25em;
    position: fixed;
    top: 0;
    width: 100%;
    transition: background-color 0.4s ease-in;
}

nav.scrolled {
    background-color: var(--navBack);
}

nav #nav-check {
    display: none;
}

nav .nav-btn {
    display: none;
}

nav h1 {
    margin: 0;
}

nav a {
    text-decoration: none;
    color: #FFFFFF;
}

nav ul {
    display: flex;
    flex-direction: row;
    gap: 1em;
    margin: 0;
    justify-content: flex-end;
    align-items: flex-end;
}

nav ul li {
    list-style: none;
}

nav ul li span {
    visibility: hidden;
}

nav ul li a:hover span, nav ul li .active span {
    visibility: visible;
}

header div {
    display: flex;
    flex-direction: column;
    justify-content: center;
    align-items: center;
    padding-top: 10em;
}

header div .btn {
    margin: 2em 0;
}

header div button {
    background: none;
    border: none;
    display: inline-block;
    text-align: center;
    text-decoration: none;
    font-size: 2rem;
    cursor: pointer;
}

i.fa-chevron-down {
    color: var(--mutedGrey);
    font-size: 3.75em;
    margin: 1.5rem 0;
}

div h1 span {
    visibility: visible;
    animation: caret 1s steps(1) infinite;
}

@keyframes caret {
    50% {
        visibility: hidden;
    }
}

@media screen and (max-width: 75em) {
    nav {
        display: block;
        height: 50px;
        width: 100%;
        background-color: var(--navBack);
        position: fixed;
        top: 0;
        padding: 0;
    }

    nav a h1{
        margin-left: 1ch;
    }

    nav  .nav-btn {
        display: inline-block;
        position: absolute;
        right: 75px;
        top: -360px;
    }

    nav ul {
        position: fixed;
        display: block;
        width: 100%;
        background-color: #333;
        transition: all 0.4s ease-in;
        overflow-y: hidden;
        padding-left: 0;
        margin-top: 7px;
    }

    nav ul li a {
        display: block;
        width: 100%;
        transform: translateX(-30px);
        transition: all 0.4s ease-in;
        opacity: 0;
    }

    .nav-btn label {
        display: inline-block;
        cursor: pointer;
        width: 60px;
        height: 50px;
        position: fixed;
        -webkit-transform: rotate(0deg);
        -moz-transform: rotate(0deg);
        -o-transform: rotate(0deg);
        transform: rotate(0deg);
        -webkit-transition: .5s ease-in;
        -moz-transition: .5s ease-in;
        -o-transition: .5s ease-in;
        transition: .5s ease-in;
    }

    .nav-btn label span {
        display: block;
        position: absolute;
        height: 5px;
        width: 100%;
        background-color: #FFFFFF;
        opacity: 1;
        right: 0;
        top: 20px;
        -webkit-transform: rotate(0deg);
        -moz-transform: rotate(0deg);
        -o-transform: rotate(0deg);
        transform: rotate(0deg);
        -webkit-transition: .25s ease-in;
        -moz-transition: .25s ease-in;
        -o-transition: .25s ease-in;
        transition: .25s ease-in;
    }

    nav  #nav-check:not(:checked) ~ ul{
        height: auto;
        max-height: 0;
    }

    nav #nav-check:not(:checked) ~ .nav-btn label span:nth-child(1) {
        top: 8px;
        -webkit-transform-origin: left center;
        -moz-transform-origin: left center;
        -o-transform-origin: left center;
        transform-origin: left center;
    }

    nav #nav-check:not(:checked) ~ .nav-btn label span:nth-child(2) {
        top: 23px;
        -webkit-transform-origin: left center;
        -moz-transform-origin: left center;
        -o-transform-origin: left center;
        transform-origin: left center;
    }

    nav #nav-check:not(:checked) ~ .nav-btn label span:nth-child(3) {
        top: 38px;
        -webkit-transform-origin: left center;
        -moz-transform-origin: left center;
        -o-transform-origin: left center;
        transform-origin: left center;
    }

    nav .nav-btn  label:hover, nav  #nav-check:checked ~ .nav-btn  label {
        background-color: rgba(-1, 0, 0, 0.3);
    }

    nav #nav-check:checked ~ ul{
        max-height: 50vh;
        overflow-y: hidden;
    }

    nav #nav-check:checked ~ ul li a {
        opacity: 1;
        transform: translateX(0px);
    }

    nav #nav-check:checked ~ ul li:nth-child(1) a {
        transition-delay: 0.15s;
    }

    nav #nav-check:checked ~ ul li:nth-child(2) a {
        transition-delay: 0.25s;
    }

    nav #nav-check:checked ~ ul li:nth-child(3) a {
        transition-delay: 0.35s;
    }

    nav #nav-check:checked ~ ul li:nth-child(4) a {
        transition-delay: 0.45s;
    }

    nav #nav-check:checked ~ ul li:nth-child(5) a {
        transition-delay: 0.55s;
    }

    nav #nav-check:checked ~ .nav-btn label span:first-child {
        -webkit-transform: rotate(45deg);
        -moz-transform: rotate(45deg);
        -o-transform: rotate(45deg);
        transform: rotate(45deg);
    }

    nav #nav-check:checked ~ .nav-btn label span:nth-child(2){
        width: 0;
        opacity: 0;
    }

    nav #nav-check:checked ~ .nav-btn label span:last-child {
        -webkit-transform: rotate(-45deg);
        -moz-transform: rotate(-45deg);
        -o-transform: rotate(-45deg);
        transform: rotate(-45deg);
    }
}

@media screen and (max-width: 31em) {
    header div h1{
        width: min-content;
    }
}