サイドに固定

デモ

See the Pen nav 17 by logsuke (@design-list) on CodePen.

コード

<!-- Boxicons headタグ内へ -->
<link href='https://unpkg.com/boxicons@2.1.2/css/boxicons.min.css' rel='stylesheet'>

     <header class="header" id="header">
          <nav id="nav" class="nav">
               <a href="#" class="logo">
                    <svg viewBox="0 0 496 512" width="100" title="meh-rolling-eyes">
                         <path
                              d="M248 8C111 8 0 119 0 256s111 248 248 248 248-111 248-248S385 8 248 8zM88 224c0-24.3 13.7-45.2 33.6-56-.7 2.6-1.6 5.2-1.6 8 0 17.7 14.3 32 32 32s32-14.3 32-32c0-2.8-.9-5.4-1.6-8 19.9 10.8 33.6 31.7 33.6 56 0 35.3-28.7 64-64 64s-64-28.7-64-64zm224 176H184c-21.2 0-21.2-32 0-32h128c21.2 0 21.2 32 0 32zm32-112c-35.3 0-64-28.7-64-64 0-24.3 13.7-45.2 33.6-56-.7 2.6-1.6 5.2-1.6 8 0 17.7 14.3 32 32 32s32-14.3 32-32c0-2.8-.9-5.4-1.6-8 19.9 10.8 33.6 31.7 33.6 56 0 35.3-28.7 64-64 64z" />
                    </svg>
                    <span class="text">logo</span>
               </a>
               <div class="nav-menu" id="navMenu">
                    <ul class="nav-links">
                         <li class="nav-item">
                              <a href="#section1" class="nav-link">
                                   <i class='bx bx-wink-tongue'></i>
                                   <span class="text">Section1</span>
                              </a>
                         </li>
                         <li class="nav-item"><a href="#section2" class="nav-link"><i class='bx bx-dizzy'></i><span
                                        class="text">Section2</span></a></li>
                         <li class="nav-item"><a href="#section3" class="nav-link"><i class='bx bx-cool'></i><span
                                        class="text">Section3</span></a></li>
                         <li class="nav-item"><a href="#section4" class="nav-link"><i
                                        class='bx bx-happy-heart-eyes'></i><span class="text">Section4</span></a></li>
                    </ul>
               </div>

               <div class="bottom">
                    <ul class="nav-links">
                         <li class="nav-item"><a href="#section5" class="nav-link"><i
                                        class='bx bx-meh-blank'></i>Section5</a></li>
                    </ul>
               </div>

               <div class="nav-toggle" id="navToggle">
                    <i id="navIcon" class='bx bx-chevrons-left'></i>
               </div>
          </nav>
     </header>

/*=== Base ===*/

* {
     margin: 0;
     padding: 0;
     box-sizing: border-box
}

:root {
     --nav-height: 8rem;
     --max-width: 1024px;
     --container-padding: 0 4rem;
     --gap: 2rem;
     --bg-color: rgb(240, 240, 240);
}

/*=== Font ratio ===*/

html {
     scroll-behavior: smooth;
     font-size: 62.5%;
}

body {
     font-size: 1.6rem;
}

ul {
     list-style: none;
}

a {
     text-decoration: none;
}

/* header */
header {}

/* nav */
.nav {
     height: 100%;
     width: 200px;
     position: fixed;
     top: 0;
     left: 0;
     z-index: 100;
     background-color: var(--bg-color);
     padding: 2rem 0;
     display: flex;
     flex-direction: column;
     transition: width .3s;
}

.nav.toggle {
     width: 65px;
}

.nav .text {
     transition: opacity .2s;
}

.nav.toggle .text {
     opacity: 0;
     pointer-events: none;
}

.logo,
.nav-toggle {
     color: var(--text-color);
     cursor: pointer;
     z-index: 200;
}

.logo {
     font-weight: bold;
     font-size: 2rem;
     display: flex;
     align-items: center;
     padding: 0 1rem;
     gap: 1rem;
     height: var(--nav-height);
}

.logo svg {
     flex-basis: 40px;
     flex-shrink: 0;
     display: block;
}



.nav-toggle {
     font-size: 3rem;
     position: absolute;
     top: calc(var(--nav-height) / 2);
     right: -1.5rem;
}

#navIcon {
     transition: .5s;
}

#navIcon.toggle {
     transform: rotate(180deg);
}

.nav-links {
     display: flex;
     flex-direction: column;
}

.nav-links .nav-link {
     height: var(--nav-height);
     display: flex;
     align-items: center;

     font-size: 1.6rem;
     display: flex;
     padding: 0 1rem;
     gap: 1rem;
     transition: all .3s;
}

.nav-links .nav-link i {
     flex-basis: 40px;
     flex-shrink: 0;
     font-size: 3rem;
     text-align: center;
}

.bottom {
     margin-top: auto;
}

.bottom .nav-link {
     transition: all .3s;
}

.nav.toggle .bottom .nav-link {
     /* writing-mode: vertical-rl;
     -webkit-writing-mode: verticsl-rl;
     transform: translateY(-50px);
     margin-bottom: 5rem; */
     transform: rotate(-90deg);
}

.nav-links a {
     color: var(--text-color);
}

const nav = document.getElementById('nav'),
    navToggle = document.getElementById('navToggle'),
    navIcon = document.getElementById('navIcon'),
    navLink = document.querySelectorAll('.nav-link')

navToggle?.addEventListener('click', function () {
    nav.classList.toggle('toggle')
    navIcon.classList.toggle('toggle')
})

navLink.forEach(function (li) {
    li.addEventListener('click', function () {
        nav.classList.add('toggle')
        navIcon.classList.add('toggle')
    })
})