:root {
    /* #4B9C95 */
    --header-bg: #eee;
    --section-bg: #4968bd;
    --button-bg: #97abd7;
}

/* =================== header ==================== */

.header {
    height: 50px;
    background-color: var(--header-bg);
    border-radius: 40px;
    /* border: solid 1px black; */
    margin: 15px;
    display: flex;
    justify-content: space-between;
    align-items: center;
    position: sticky;
    top: 0;
    z-index: 2;
    padding: 30px;
    
    font-size: clamp(15px, 4vw, 25px);
    color: black;
}

.menu-toggle {
    display: none;
    background: none;
    border: none;
    font-size: 24px;
    cursor: pointer;
}

.header-left {
    display: flex;
    align-items: center;
    justify-content: center;
}

.header-right {
    display: flex;
    gap: 25px;
    align-items: center;
    justify-content: center;
}

.share-button {
    width: 70px;
    height: 70px;
    border: none;
    border-radius: 20px;
    background-color: var(--button-bg);
    color: white;
    font-size: 100%;

    display: flex;
    justify-content: center;
    align-items: center;

    cursor: pointer;
}

/* =================== toggle ==================== */
@media (max-width: 800px) {
    .menu-toggle {
        display: block;
    }
    .header-right {
        display: none;
        position: absolute;
        top: 70px;
        width: 35vw;
        right: 0;
        background-color: var(--header-bg);
        border-radius: 0 0 20px 20px;
        padding: 30px;
        flex-direction: column;
        align-items: flex-start;
    }

    .header-right::before {
        content: "";
        position: absolute;
        top: 40px;
        left: -20px;
        width: 20px;
        height: 20px;
        background: radial-gradient(circle at bottom left, transparent 20px, var(--header-bg) 20px);
    }

    .icon-arrow {
        display: none;
    }

    /* メニューが開いている時のスタイル */
    .header.menu-open .header-right {
        display: flex;
    }
    .header.menu-open .icon-hamburger {
        display: none;
    }
    .header.menu-open .icon-arrow {
        display: block;
    }
}

/* =================== section ==================== */
.section-title {
    margin: 20px 20px 0px 20px;
    background-color: var(--section-bg);
    height: 60px;
    border-radius: 20px 20px 0 0;
    width: clamp(100px, 35vw, 350px);
    position: relative;
    /* 以下テキストの位置 */
    display: flex;
    justify-content: center;
    align-items: center;
    font-size: clamp(15px, 4vw, 25px);
    font-weight: 600;
    color: white;
}
/* 滑らかにつなげたい */
.section-title::after {
    content: "";
    position: absolute;
    bottom: 0;
    right: -20px;
    width: 20px;
    height: 20px;
    /* 右上角中心の円、中心から半径20pxの範囲transparent、半径20pxより外色指定 */
    background: radial-gradient(circle at top right, transparent 20px, var(--section-bg) 20px);
}

.section {
    background-color: var(--section-bg);
    height: 200px;
    margin: 0px 20px 20px 20px;
    border-radius: 0 20px 20px 20px;
}