body {
    background: #f8f8f8;
    font-family: "Microsoft JhengHei", Arial, sans-serif;
    font-size: 18px;
    color: #222;
    margin: 0;
    padding: 0;
}
.container {
    max-width: 600px;
    margin: 20px auto;
    background: #fff;
    border-radius: 18px;
    box-shadow: 0 4px 24px rgba(0,0,0,0.8);
    padding: 24px 20px;
}
header h1 {
    font-size: 1.8em;
    margin-bottom: 0.2em;
    color: #0055a5;
    text-align: center;
}
.subtitle {
    font-size: 1em;
    color: #333;
    text-align: center;
    margin-bottom: 1.2em;
}
section {
    margin-bottom: 1.5em;
}
.upload-area {
    border: 2px dashed #0055a5;
    border-radius: 12px;
    background: #eaf3fa;
    padding: 24px 0;
    text-align: center;
    cursor: pointer;
    transition: background 0.2s;
}
.upload-area:hover {
    background: #d2e7f7;
}
.upload-icon {
    font-size: 2em;
    margin-bottom: 0.4em;
}
.upload-btn {
    font-size: 1em;
    background: #0055a5;
    color: #fff;
    border: none;
    border-radius: 8px;
    padding: 10px 24px;
    margin-top: 0.8em;
    cursor: pointer;
    transition: background 0.2s;
}
.upload-btn:hover {
    background: #003d7a;
}
.images-container {
    display: flex;
    flex-wrap: wrap;
    gap: 12px;
    margin-top: 10px;
}
.images-container img {
    width: 70px;
    height: 70px;
    object-fit: contain;
    background: #f0f0f0;
    border: 2px solid #bbb;
    border-radius: 8px;
    margin-bottom: 3px;
}
.images-container .img-actions {
    display: flex;
    justify-content: center;
    gap: 6px;
}
.img-action-btn {
    font-size: 1.1em;
    background: #eee;
    border: none;
    border-radius: 6px;
    padding: 3px 8px;
    cursor: pointer;
    transition: background 0.2s;
}
.img-action-btn:hover {
    background: #ffd700;
}
.animation-controls {
    display: flex;
    flex-direction: column;
    gap: 14px;
    margin-top: 8px;
}
.control-group label {
    font-size: 0.9em;
    margin-right: 8px;
}
#frameDuration {
    width: 160px;
    vertical-align: middle;
}
.warning {
    color: #d32f2f;
    font-weight: bold;
    margin-left: 10px;
}
.preview-container {
    text-align: center;
}
.preview-frame {
    width: 270px;
    height: 270px;
    margin: 0 auto 10px auto;
    background: #f0f0f0;
    border: 2px solid #bbb;
    border-radius: 12px;
    display: flex;
    align-items: center;
    justify-content: center;
}
.preview-frame img {
    width: 100%;
    height: 100%;
    object-fit: contain;
}
.preview-controls {
    display: flex;
    justify-content: center;
    gap: 14px;
}
.control-btn {
    font-size: 1.2em;
    background: #0055a5;
    color: #fff;
    border: none;
    border-radius: 8px;
    padding: 6px 16px;
    cursor: pointer;
    transition: background 0.2s;
}
.control-btn:hover {
    background: #003d7a;
}
.download-btn {
    font-size: 1.1em;
    background: #43a047;
    color: #fff;
    border: none;
    border-radius: 8px;
    padding: 12px 32px;
    margin-top: 0.8em;
    cursor: pointer;
    transition: background 0.2s;
}
.download-btn:hover {
    background: #2e7031;
}
footer {
    text-align: center;
    color: #888;
    font-size: 0.9em;
    margin-top: 1.5em;
}