ポップアップウィンドウ：ネイチャー｜Pop-up Window: Nature

<div class="container">
    <button id="popup-btn">Nature</button>
</div>

<div id="popup" class="popup">
    <div class="popup-content">
        <p class="title">Nature Popup</p>
        <p>自然をテーマにしたオーガニックなポップアップウィンドウです。</p>
    </div>
</div>

.container {
    text-align: center;
}

#popup-btn {
    cursor: pointer;
    border: none;
    padding: 12px 24px;
    border-radius: 16px;
    color: #333;
    background-color: #eee;
    font-weight: 600;
    box-shadow: 0 0 4px rgba(0, 0, 0, 0.3);
    display: block;
    margin: 0 auto;
    width: 180px;
}

#popup-btn:hover {
    opacity: 0.5;
}

.popup {
    position: fixed;
    bottom: -100%;
    left: 50%;
    transform: translateX(-50%);
    z-index: 1001;
    opacity: 0;
    visibility: hidden;
    transition: all 0.3s ease;
    max-width: 90%;
    max-height: 90%;
}

.popup.active {
    opacity: 1;
    visibility: visible;
    bottom: 20px;
    transform: translateX(-50%);
    animation: popupShowHide 3.4s ease forwards;
}

@keyframes popupShowHide {
    0% {
        opacity: 0;
        transform: translateX(-50%) translateY(100%);
    }
    20% {
        opacity: 1;
        transform: translateX(-50%) translateY(0);
    }
    80% {
        opacity: 1;
        transform: translateX(-50%) translateY(0);
    }
    100% {
        opacity: 0;
        transform: translateX(-50%) translateY(100%);
    }
}

.popup-content {
    background: linear-gradient(135deg, #a8e6cf 0%, #dcedc1 50%, #ffd3b6 100%);
    padding: 35px;
    border-radius: 25px;
    text-align: center;
    position: relative;
    min-width: 320px;
    box-shadow: 
        0 15px 35px rgba(168, 230, 207, 0.3),
        0 5px 15px rgba(0, 0, 0, 0.1);
    border: 3px solid #4caf50;
    animation: natureFloat 4s ease-in-out infinite;
    overflow: hidden;
}

@keyframes natureFloat {
    0%, 100% {
        transform: translateY(0px) rotate(0deg);
    }
    25% {
        transform: translateY(-8px) rotate(0.5deg);
    }
    50% {
        transform: translateY(-4px) rotate(-0.5deg);
    }
    75% {
        transform: translateY(-6px) rotate(0.3deg);
    }
}

.popup-content p.title {
    font-size: 26px;
    font-weight: bold;
    margin-bottom: 15px;
    color: #2e7d32;
    text-shadow: 0 2px 4px rgba(46, 125, 50, 0.2);
    animation: natureText 3s ease-in-out infinite;
    position: relative;
    z-index: 1;
}

@keyframes natureText {
    0%, 100% {
        transform: scale(1);
    }
    50% {
        transform: scale(1.02);
    }
}

.popup-content p {
    font-size: 16px;
    color: #388e3c;
    margin-bottom: 0;
    line-height: 1.6;
    font-weight: 500;
    position: relative;
    z-index: 1;
}

/* レスポンシブ対応 */
@media (max-width: 768px) {
    .popup-content {
        padding: 25px;
        min-width: 280px;
    }
    
    .popup-content h2 {
        font-size: 22px;
    }
    
    .popup-content p {
        font-size: 14px;
    }
    
    #popup-btn {
        padding: 12px 24px;
        font-size: 14px;
    }
}

@media (max-width: 480px) {
    .popup-content {
        padding: 20px;
        min-width: 250px;
    }
    
    .popup-content h2 {
        font-size: 20px;
    }
    
    .popup-content p {
        font-size: 13px;
    }
    
    #popup-btn {
        padding: 10px 20px;
        font-size: 13px;
    }
}

document.addEventListener('DOMContentLoaded', function() {
    const popupBtn = document.getElementById('popup-btn');
    const popup = document.getElementById('popup');
    
    popupBtn.addEventListener('click', function() {
        popup.classList.add('active');
    });

    popup.addEventListener('animationend', function() {
        popup.classList.remove('active');
    });
});