body {
    background: #0d1117; color: #f1f1f1;
    font-family: 'Pretendard', sans-serif;
    display: flex; flex-direction: column;
    align-items: center; justify-content: center;
    height: 100vh; text-align: center;
    }
h1 { font-size: 2rem; margin-bottom: 1rem; }
button {
    background: #00bfa5; color: white;
    border: none; border-radius: 8px;
    padding: 10px 20px; font-size: 1rem;
    cursor: pointer; transition: 0.2s;
    }
button:hover { background: #009688; }
pre {
    background: #5b5e70;
    padding: 20px;
    border-radius: 8px;
    box-shadow: 0 2px 6px rgba(0,0,0,0.1);
    text-align: left;
    white-space: pre-wrap;
    word-break: keep-all;
    display: none; /* ✅ 처음엔 안 보이게 */
    opacity: 0;
    transition: opacity 0.4s ease;
    margin-top: 20px;
}
pre.visible {
    display: inline-block;
    opacity: 1; /* ✅ 결과 나올 때 부드럽게 보이게 */
}
#copyBtn {
    display: none; /* ✅ 결과 나오기 전에는 숨김 */
    background: #28a745;
}
.ad-banner {
    width: 320px;
    margin: 0 auto;
}