Popup / 19 ペーパーフォールド

デザイン見本

紙を折りたたんで開くような動き（scaleY）を取り入れたデザインです。右上の折り返し（ドッグイヤー）装飾が、アナログな質感をプラスしています。

実装コード

HTML

<div id="popup-container-19">
                        <button id="popup-btn-19">Paper Fold</button>
                    </div>
                    <div id="popup-19" class="popup-19">
                        <div class="popup-content-19">
                            <p>Paper Fold Popup</p>
                            <p>折り紙のような立体的なデザインのポップアップです。</p>
                        </div>
                    </div>

CSS

#popup-btn-19 {
    cursor: pointer;
    border: none;
    padding: 12px 24px;
    border-radius: 16px;
    font-weight: 600;
    display: block;
    margin: 0 auto;
    width: 180px;
    color: #2c3e50; background-color: #ecf0f1; border-bottom: 3px solid #bdc3c7;
}
#popup-btn-19:hover {
    opacity: 0.5;
}
.popup-19 {
    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-19.active {
    opacity: 1;
    visibility: visible;
    bottom: 20px;
    transform: translateX(-50%);
    animation: popupShowHide19 3.4s ease forwards;
}
@keyframes popupShowHide19 {
    0% {
        opacity: 0;
        transform: translateX(-50%) translateY(100%) rotateX(15deg) rotateY(-15deg);
    }
    20% {
        opacity: 1;
        transform: translateX(-50%) translateY(0) rotateX(0deg) rotateY(0deg);
    }
    80% {
        opacity: 1;
        transform: translateX(-50%) translateY(0) rotateX(0deg) rotateY(0deg);
    }
    100% {
        opacity: 0;
        transform: translateX(-50%) translateY(100%) rotateX(-15deg) rotateY(15deg);
    }
}
.popup-content-19 {
    background: #ffffff;
    padding: 40px;
    border-radius: 0;
    text-align: center;
    position: relative;
    min-width: 320px;
    box-shadow: 
        0 0 0 1px #e0e0e0,
        0 8px 16px rgba(0,0,0,0.1),
        0 4px 8px rgba(0,0,0,0.05);
    animation: paperFold 0.6s ease-out;
}
@keyframes paperFold {
    0% {
        opacity: 0;
        transform: scale(0.8) rotate(5deg);
    }
    100% {
        opacity: 1;
        transform: scale(1) rotate(0deg);
    }
}
.popup-content-19::before {
    content: '';
    position: absolute;
    top: 0;
    right: 0;
    width: 0;
    height: 0;
    border-style: solid;
    border-width: 0 30px 30px 0;
    border-color: transparent #f0f0f0 transparent transparent;
    box-shadow: -2px 2px 4px rgba(0,0,0,0.1);
}
.popup-content-19::after {
    content: '';
    position: absolute;
    top: 0;
    right: 0;
    width: 0;
    height: 0;
    border-style: solid;
    border-width: 0 25px 25px 0;
    border-color: transparent #e0e0e0 transparent transparent;
}
.popup-content-19 p:first-child {
    font-size: 28px;
    font-weight: bold;
    margin-bottom: 20px;
    color: #2c3e50;
    text-shadow: 2px 2px 4px rgba(0,0,0,0.1);
    border-bottom: 3px solid #3498db;
    padding-bottom: 10px;
    font-family: 'Georgia', serif;
}
.popup-content-19 p:last-of-type {
    font-size: 16px;
    color: #555;
    margin-bottom: 0;
    line-height: 1.8;
    font-weight: 400;
    font-style: italic;
}

var btn = document.getElementById('popup-btn-19');
var popup = document.getElementById('popup-19');

if (btn && popup) {
  btn.addEventListener('click', function () {
    popup.classList.add('active');
  });

  popup.addEventListener('animationend', function (e) {
    if (e.animationName.startsWith('popupShowHide')) {
      popup.classList.remove('active');
    }
  });
}