body {
    margin: 0;
    padding: 0;
    display: flex;
    flex-direction: column;
    align-items: center;
    height: 100vh;
    background-color: #f0f0f0;
    font-family: Arial, sans-serif;
}

h1 {
    margin: 10px 0;
    font-size: 24px;
    color: #333;
}

.container {
    display: flex;
    width: 90%;
    height: calc(100vh - 50px);
    border: 1px solid #ccc;
    background-color: white;
    box-sizing: border-box;
}

/* 左边：PDF 显示区 */
.pdf-viewer {
    flex: 3;
    border-right: 1px solid #ccc;
    overflow-y: auto;
    padding: 10px;
    background-color: #f9f9f9;
    display: flex;
    flex-direction: column;
    align-items: center;
    position: relative; /* 用于定位加载提示 */
}

/* PDF 加载提示 */
.loading {
    position: absolute;
    top: 50%;
    left: 50%;
    transform: translate(-50%, -50%);
    font-size: 18px;
    color: #007bff;
}

/* PDF 页面样式 */
.pdf-page {
    margin-bottom: 10px;
    box-shadow: 0 0 10px rgba(0, 0, 0, 0.1);
    max-width: 100%;
    height: auto;
}

/* 右边：功能区 */
.control-panel {
    flex: 1;
    display: flex;
    flex-direction: column;
    padding: 10px;
    background-color: #f9f9f9;
    overflow-y: auto;
}

/* 计时器显示 */
.timer {
    margin-bottom: 10px;
    font-size: 48px;
    color: #333;
    text-align: center;
}

.file-upload {
    margin-bottom: 10px;
    display: flex;
    flex-direction: column;
    align-items: flex-start;
}

.file-upload label {
    display: inline-block;
    padding: 10px 20px;
    background-color: #007bff;
    color: white;
    border-radius: 5px;
    cursor: pointer;
    text-align: center;
    width: 100%;
    box-sizing: border-box;
}

.file-upload input {
    display: none;
}

.file-upload span {
    margin-top: 5px;
    font-size: 14px;
    color: #333;
}

.music-player {
    margin-bottom: 10px;
}

.music-player audio {
    width: 100%;
}

.sync-controls {
    margin-bottom: 10px;
}



.sync-input button {
    padding: 10px;
    background-color: #dc3545;
    color: white;
    border: none;
    border-radius: 5px;
    cursor: pointer;
}

#add-input {
    width: 100%;
    padding: 10px;
    background-color: #28a745;
    color: white;
    border: none;
    border-radius: 5px;
    cursor: pointer;
    margin-bottom: 10px;
}

#start-button {
    width: 100%;
    padding: 10px;
    background-color: #ffc107;
    color: white;
    border: none;
    border-radius: 5px;
    cursor: pointer;
    margin: 10px;
}

#restart-button {
    width: 100%;
    padding: 10px;
    background-color: #ffc107;
    color: white;
    border: none;
    border-radius: 5px;
    cursor: pointer;
    margin: 10px;
}

.sync-input {
    display: flex;
    align-items: center;
    margin-bottom: 10px;
}

.sync-input input {
    width: 20%;
    flex: 1;
    padding: 10px;
    margin-right: 10px;
    border: 1px solid #ccc;
    border-radius: 5px;
}

.save-controls {
    //display: flex;
    align-items: center;
    margin-bottom: 10px;
}
.save-controls button {
    width: 100%;
    padding: 10px;
    background-color: #28a745;
    color: white;
    border: none;
    border-radius: 5px;
    cursor: pointer;
}