/* Reset CSS */
*, *::before, *::after {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

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

body {
    font-family: 'Noto Sans JP', 'Poppins', sans-serif;
    font-size: 1.6rem;
    line-height: 1.6;
    color: #fff;
    overflow-x: hidden;
    background-color: #0a2540; /* 深い海の色 */
    background-image: linear-gradient(to bottom, #0a2540, #0c4a6e); /* グラデーションで深い海から少し明るい青へ */
}

a {
    text-decoration: none;
    color: inherit;
}

ul, ol {
    list-style: none;
}

img, video {
    max-width: 100%;
    height: auto;
    display: block;
}

button, input, textarea {
    font-family: inherit;
    font-size: inherit;
    color: inherit;
    border: none;
    background: none;
    outline: none;
}

button {
    cursor: pointer;
}

h1, h2, h3, h4, h5, h6 {
    font-weight: 700;
    line-height: 1.2;
}