/* ===== CSS重置 ===== */
*, *::before, *::after {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}
html {
    scroll-behavior: smooth;
    -webkit-text-size-adjust: 100%;
}
body {
    font-family: var(--font-primary);
    font-size: 16px;
    line-height: 1.6;
    color: var(--dark-gray);
    background-color: var(--ivory);
    overflow-x: hidden;
    -webkit-font-smoothing: antialiased;
    -moz-osx-font-smoothing: grayscale;
}
a {
    color: inherit;
    text-decoration: none;
}
ul, ol {
    list-style: none;
}
img {
    max-width: 100%;
    display: block;
}
button {
    cursor: pointer;
    border: none;
    background: none;
    font-family: inherit;
    font-size: inherit;
}
input, select, textarea {
    font-family: inherit;
    font-size: inherit;
}
h1, h2, h3, h4, h5, h6 {
    line-height: 1.2;
    font-weight: 700;
}
h1 { font-size: 2rem; }
h2 { font-size: 1.5rem; }
h3 { font-size: 1.25rem; }
h4 { font-size: 1.1rem; }