@charset "UTF-8";
body, html {
            margin: 0;
            padding: 0;
            height: 100%;
            background-color: #000;
            background-image: url(../img/back.jpg);
            background-size: cover;
            background-position: center;
            min-height: 100vh;
            font-family: "Yu Mincho", "Noto serif";
            color: white;
            font-size: 16px;
            overflow: hidden;
        }

        /* 全体のコンテナ */
        .wrapper {
            position: relative; /* 子要素の基準点 */
            display: flex;
            flex-direction: column;
            justify-content: space-between;
            height: 100vh;
            padding: 60px 5%; /* 左側の余白を5%に（より端へ） */
            box-sizing: border-box;
            z-index: 10;
        }

        /* 1. タイトル（左端） */
        .header-title {
            font-size: 1.2rem;
            letter-spacing: 0.5em;
            font-weight: 200;
            margin: 0;
            position: relative;
            z-index: 20; /* 画像より前面に */
        }

        /* 2. ナビゲーション（左端・中央付近） */
        .side-nav-container {
            flex: 1;
            display: flex;
            align-items: center; /* 垂直方向の中央 */
        }

        .side-nav {
            display: flex;
            flex-direction: column;
            gap: 30px;
            list-style: none;
            padding: 0;
            margin: 0;
            opacity: 0;
            animation: navFirstAppearance 3s linear forwards;
            animation-delay: 8s;
            position: relative;
            z-index: 20;
        }

        .side-nav li a {
            color: white;
            text-decoration: none;
            font-size: 0.8rem;
            letter-spacing: 0.3em;
            /* opacity: 0.5; */
            transition: all 0.5s ease;
            display: block;
        }

        .side-nav li a:hover {
            letter-spacing: 0.5em;
            color: rgb(128, 151, 166);
            transform: translateX(10px);
        }

        /* 3. ★画像コンテナ（画面の絶対中央に固定） */
        .image-center-wrapper {
            position: absolute;
            top: 50%;
            left: 50%;
            transform: translate(-50%, -50%); 
            width: 400px;
            height: 400px;
            display: flex;
            justify-content: center;
            align-items: center;
            z-index: 5; /* タイトルやナビの下 */
        }

        /* --- アニメーション要素（設定は維持） --- */
        .circle {
            position: absolute;
            width: 10mm;
            height: 10mm;
            background-color: #2e2e2d;
            border-radius: 50%;
            animation: circleStay 15s linear infinite;
        }

        .target-image {
            position: absolute;
            width: 800px;
            height: 700px;
            object-fit: cover;
            animation: finalWaveEmerge 15s linear infinite ;
            animation-iteration-count: 1;
        }

        /* --- アニメーション定義 --- */
        @keyframes finalWaveEmerge {
            0%, 20% { transform: scale(0); filter: blur(30px); opacity: 0; }
            50% { transform: scale(0.65); filter: blur(10px); opacity: 1; }
            90% { transform: scale(1); filter: blur(0px); opacity: .5;  }
            100% { transform: scale(1); filter: blur(0px); opacity: 1;  }
        }

        @keyframes circleStay {
            0%, 20% { opacity: 1; transform: scale(1); }
            35%, 100% { opacity: 0; transform: scale(1.2); }
        }

        @keyframes navFirstAppearance {
            0% { opacity: 0; filter: blur(10px); transform: translateX(-20px); }
            80%,100% { opacity: 1; filter: blur(0px); transform: translateX(0); }
        }

        /* レスポンシブ */
        @media (max-width: 480px) {
           body, html {
            text-shadow: 2px 2px 4px rgba(0, 0, 0, .9);
            font-size: 14px;
           }
            .target-image {
                width: 500px;
                height: 500px;
            }
            nav{
                margin: 0 auto;
            }
        }