/* 基本スタイル */
body {
    font-family: Arial, sans-serif;
    margin: 0;
    padding: 0;
    background-image: url('background.jpg'); /* 背景画像 */
    background-size: cover;
    color: white;
}

.site-header, .site-footer {
    background-color: rgba(0, 0, 0, 0.7);
    text-align: center;
    padding: 1em 0;
}

.introduction, .features {
    background-color: rgba(0, 0, 0, 0.5);
    margin: 1em;
    padding: 1em;
    border-radius: 10px;
}

.styled-button {
    font-size: 1.2em;
    padding: 15px 40px;
    background-color: #007bff;
    color: white;
    border: none;
    border-radius: 10px;
    box-shadow: 0 4px 6px rgba(0, 0, 0, 0.2);
    cursor: pointer;
    transition: background-color 0.3s ease;
    margin-top: 30px;
}

.styled-button:hover {
    background-color: #0056b3;
}

body {
    background:#ffffff;
}

.top-link-fixed {
    position: fixed;
    top: 20px;
    right: 20px;
    z-index: 1000;
    background-color: #ffffffcc;
    padding: 10px 20px;
    border-radius: 8px;
    text-decoration: none;
    color: #007bff;
    font-weight: bold;
    box-shadow: 0 2px 4px rgba(0,0,0,0.2);
    transition: background-color 0.3s ease;
}

.top-link-fixed:hover {
    background-color: #f0f0f0;
}

/*
 * スマホ対応
 */
@media screen and (max-width: 600px) {
    .top-link-fixed {
        top: auto;
        bottom: 20px;
        right: 20px;
        padding: 12px 16px;
        font-size: 0.95rem;
    }
}


/* スマートフォン対応 */
@media (max-width: 768px) {
    .introduction, .features {
        margin: 0.5em;
        padding: 0.5em;
    }
}