body {
    font-family: sans-serif;
    padding: 20px;
    background-color: #f4f4f9;
}

.container {
    max-width: 600px;
    margin: 0 auto;
    background: white;
    padding: 30px;
    border-radius: 8px;
    box-shadow: 0 2px 10px rgba(0,0,0,0.1);
    border: 2px solid transparent; /* 预留边框位置避免抖动 */
    transition: all 0.2s ease;
}

.btn-group {
    margin: 20px 0;
}

button {
    padding: 8px 16px;
    cursor: pointer;
    margin-right: 10px;
    background-color: #007bff;
    color: white;
    border: none;
    border-radius: 4px;
}

button:hover {
    background-color: #0056b3;
}

#fileName {
    color: #555;
    font-weight: bold;
    margin-left: 10px;
}

/* --- 拖拽相关样式 --- */
.container.drag-over {
    border: 2px dashed #007bff;
    background-color: #f0f8ff;
    transform: scale(1.01);
}

.drag-hint {
    text-align: center;
    color: #888;
    margin-top: 5px;
    font-size: 0.9em;
}

.container.drag-over .drag-hint {
    color: #007bff;
    font-weight: bold;
}

/* 添加到文件末尾 */
.footer-info {
    margin-top: 25px;
    padding-top: 15px;
    border-top: 1px dashed #eee;
    text-align: center;
    font-size: 0.75em;
    color: #bbb;
}

.footer-info a {
    color: #bbb;
    text-decoration: none;
}

.footer-info a:hover {
    color: #007bff;
    text-decoration: underline;
}