.hamburger-icon, .hamburger-btn {
    width: var(--hamburger-menu-width);
    height: calc(var(--hamburger-stick-height) * 3 + var(--hamburger-inner-gap) * 2);
    margin: 0 0 0 var(--hamburger-left-margin);
    padding: 0;
    border: 0;
    background: none;
    display: flex;
    flex-direction: column;
    gap: var(--hamburger-inner-gap);
    z-index: 3;
}

.hamburger-icon {
    /* display: flex;
    flex-direction: column;
    gap: var(--hamburger-inner-gap);
    z-index: 3;
    position: absolute; */
}

.hamburger-btn {
    /* display: block;
    z-index: 4; */
}

.hamburger-btn:hover {
    cursor: pointer;
}

.menu-stick {
    display: block;
    width: var(--hamburger-menu-width);
    height: var(--hamburger-stick-height);
    background-color: #eee;
    border-radius: 2px;
    transition: transform 0.4s, opacity 0.4s, background-color 0.1s;
}

.hamburger-btn:hover .menu-stick {
    background-color: #bbb;
}

/* ハンバーガーがXに変形 */
.hamburger-btn.opened .menu-stick:nth-child(1) {
    transform: translateY(calc(var(--hamburger-stick-height) + var(--hamburger-inner-gap))) rotate(45deg);
}

.hamburger-btn.opened .menu-stick:nth-child(2) {
    opacity: 0;
}

.hamburger-btn.opened .menu-stick:nth-child(3) {
    transform: translateY(calc(-1 * (var(--hamburger-stick-height) + var(--hamburger-inner-gap)))) rotate(-45deg);
}

.hamburger-btn.opened .menu-stick {
    background-color: #222;
}

.hamburger-btn.opened:hover .menu-stick {
    background-color: #444;
}

/* オーバーレイ背景 */
.overlay {
    position: fixed;
    inset: 0;
    background-color: rgba(0, 0, 0, 0.4);
    opacity: 0;
    pointer-events: none;
    transition: 0.4s;
    z-index: 1;
}

.hamburger-btn.opened~.overlay {
    opacity: 1;
    pointer-events: auto;
}

/* メニュー本体（左から出す） */
.menu {
    position: fixed;
    top: 0;
    left: calc(-1 * var(--side-menu-width) - 30px);
    /* ← 初期位置を左へ */
    width: var(--side-menu-width);
    height: 100%;
    background-color: #fff;
    box-shadow: 2px 0 8px rgba(0, 0, 0, 0.2);
    transition: left 0.4s ease;
    z-index: 2;
}

.hamburger-btn.opened~.menu {
    left: 0;
    /* ← 開いたときは左0へ */
}

.menu-header {
    background-color: #eee;
    height: var(--header-height);
    display: flex;
}

.menu-title {
    text-decoration: none;
    color: #000;
    display: block;
    margin: auto 0 auto calc(var(--header-right-left-padding) + var(--hamburger-menu-width) + var(--hamburger-left-margin) + var(--hamburger-header-title-gap));
    padding: var(--header-title-top-bottom-padding) 0;
}

.menu-title:hover, .menu-title:focus {
    color: #333;
    background-color: #ddd;
}

.menu-container {
    overflow-x: auto;
    height: calc(100% - var(--header-height));
}

.sidebar {
    list-style: none;
    margin: 20px 0 20px var(--side-menu-left-margin);
    padding: 0;
    display: flex;
    gap: 20px;
    flex-direction: column;
}

.sidebar li {
    display: flex;
}

.sidebar a {
    text-decoration: none;
    text-decoration-color: transparent;
    color: #00e;
    transition: text-decoration-color 0.1s;
    padding: 1px 4px;
}

.sidebar a:hover, .sidebar a:focus {
    text-decoration: underline;
    text-decoration-color: currentColor;
}