#return-btn {
    position: absolute; /* 绝对定位 */
    top: 20px; /* 距离顶部 20px */
    left: 20px; /* 距离左侧 20px */
    padding: 12px 24px; /* 内边距 */
    font-size: 1rem; /* 字体大小 */
    cursor: pointer; /* 鼠标悬停时显示为手型 */
    background-color: #404040; /* 修改为统一的灰色背景 */
    color: #E6E1E5; /* 按钮文字颜色 */
    border: none; /* 按钮边框样式 */
    border-radius: 20px; /* 按钮圆角大小 */
    box-shadow: 0 1px 3px rgba(0, 0, 0, 0.3); /* 按钮阴影 */
    transition: all 0.2s ease; /* 背景颜色和缩放的过渡效果 */
    z-index: 1001; /* 按钮层级 */
}

#return-btn:hover {
    background-color: #4A4A4A; /* 统一的灰色悬停背景 */
    transform: translateY(-1px); /* 悬停时向上移动 1px */
    box-shadow: 0 2px 6px rgba(0, 0, 0, 0.4); /* 悬停时的阴影效果 */
}

body {
    font-family: 'Roboto', 'HarmonyOS Sans SC', sans-serif;
    margin: 0;
    padding: 0;
    background: #121212;
    color: #E6E1E5;
    overflow: auto;
}

body::-webkit-scrollbar {
    display: none;
}

#fullscreen-btn, #settings-btn {
    position: absolute;
    top: 20px;
    padding: 12px 24px;
    font-size: 1rem;
    cursor: pointer;
    background-color: #404040;
    color: #E6E1E5;
    border: none;
    border-radius: 20px;
    box-shadow: 0 1px 3px rgba(0,0,0,0.3);
    transition: all 0.2s ease;
    z-index: 1001;
    display: flex;
    align-items: center;
}

#fullscreen-btn::before {
    content: "fullscreen";
    font-family: 'Material Icons';
    font-size: 20px;
    margin-right: 4px;
}

#settings-btn::before {
    content: "settings";
    font-family: 'Material Icons';
    font-size: 20px;
    margin-right: 4px;
}

#fullscreen-btn {
    right: 20px;
}

#settings-btn {
    right: 140px;
}

#settings-btn:hover, #fullscreen-btn:hover {
    background-color: #4A4A4A;
    transform: translateY(-1px);
    box-shadow: 0 2px 6px rgba(0,0,0,0.4);
}

.container {
    padding: 24px;
    max-width: 90%;
    margin: auto;
    background-color: #121212;
    box-shadow: 0 4px 8px rgba(0,0,0,0.2);
}

h1 {
    font-size: 3.5rem;
    font-weight: 400;
    text-align: left;
    margin-bottom: 16px;
    color: #E6E1E5;
    display: flex;
    align-items: center;
    justify-content: space-between;
}

#room {
    font-size: 3.5rem;
    font-weight: 400;
    color: #E6E1E5;
    margin-left: 20px;
}

#message {
    font-size: 1.8rem;
    color: #aaaaaa;
    margin-bottom: 24px;
}

.content {
    display: flex;
    justify-content: space-between;
    gap: 24px;
}

.left-column, .right-column {
    display: flex;
    flex-direction: column;
    gap: 24px;
}

.left-column {
    width: 50%;
}

.right-column {
    width: 50%;
}

.clock-section, .info-section, .right-column {
    background-color: #212121;
    padding: 24px;
    border-radius: 14px;
    box-shadow: 0 2px 6px rgba(0,0,0,0.2);
}

#current-time {
    font-size: 8rem;
    text-align: center;
    color: #FFFFFF;
    margin: 0;
    font-weight: 400;
}

#current-subject, #exam-timing, #remaining-time, #status {
    font-size: 3rem;
    margin: 16px 0;
    text-align: left;
    color: #FFFFFF;
}

table {
    width: 100%;
    border-collapse: separate;
    border-spacing: 0;
    margin-top: 24px;
    background-color: #212121;
    border-radius: 14px;
    overflow: hidden;
}

th, td {
    padding: 3px;
    font-size: 1.8rem;
    text-align: center;
    border-bottom: 1px solid #555555;
}

th {
    background-color: transparent;
    color: #FFFFFF;
    font-weight: 500;
}

tr:hover {
    background-color: #555555;
}

.exam-status-tag {
    padding: 2px 4px;
    border-radius: 3px;
    font-size: 1.2rem;
    font-weight: 500;
}

.exam-status-进行中 {
    background-color: #263227;
    color: green;
}

.exam-status-即将开始 {
    background-color: #594300;
    color: #FFB960;
}

.exam-status-已结束 {
    background-color: #3a2523;
    color: red;
}

.exam-status-未开始 {
    background-color: #3c2f1d;
    color: orange;
}

#settings-modal {
    display: none;
    position: fixed;
    z-index: 1000;
    left: 0;
    top: 0;
    width: 100%;
    height: 100%;
    background-color: rgba(0,0,0,0.6);
    backdrop-filter: blur(8px);
}

#settings-modal-content {
    background: #404040;
    padding: 32px 48px 32px 32px;
    margin: 32px auto;
    border-radius: 28px;
    width: 600px;
    max-height: 60vh;
    overflow-y: auto;
    box-shadow: 0 8px 24px rgba(0,0,0,0.4);
}

#settings-modal-content::-webkit-scrollbar {
    width: 8px;
}

#settings-modal-content::-webkit-scrollbar-track {
    background: transparent;
    margin: 4px;
}

#settings-modal-content::-webkit-scrollbar-thumb {
    background: #4A4458;
    border-radius: 8px;
    border: 2px solid #2B2930;
}

#settings-modal-content::-webkit-scrollbar-thumb:hover {
    background: #635B70;
}

#settings-modal-content h3 {
    margin: 0 0 24px;
    color: #E6E1E5;
    font-size: 24px;
    font-weight: 400;
}

#settings-modal-content label {
    display: flex;
    align-items: center;
    gap: 16px;
    margin: 16px 0;
    font-size: 16px;
    color: #E6E1E5;
}

#settings-modal-content input[type="number"],
#settings-modal-content input[type="text"] {
    font-size: 1.8rem;
    padding: 12px 16px;
    margin: 8px 0 24px;
    width: 100%;
    box-sizing: border-box;
    border: 2px solid #4A4458;
    border-radius: 12px;
    background-color: #332D41;
    color: #E6E1E5;
    transition: all 0.2s ease;
}

#settings-modal-content input:focus {
    outline: none;
    border-color: #D0BCFF;
    background-color: #4A4458;
}

.button-group {
    display: flex;
    justify-content: flex-end;
    gap: 16px;
    margin-top: 32px;
    position: relative;
    background-color: #404040;
    padding: 16px 0;
    border-top: 1px solid #555555;
}

#save-settings-btn, #close-settings-btn {
    padding: 12px 24px;
    border-radius: 20px;
    font-size: 16px;
    font-weight: 500;
    border: none;
    cursor: pointer;
    transition: all 0.2s ease;
    display: flex;
    align-items: center;
    gap: 8px;
}

#save-settings-btn {
    background-color: #404040;
    color: #E6E1E5;
}

#save-settings-btn::before {
    content: "✓";
    font-size: 18px;
}

#close-settings-btn {
    background-color: #404040;
    color: #E6E1E5;
}

#close-settings-btn::before {
    content: "✕";
    font-size: 18px;
}

#save-settings-btn:hover, #close-settings-btn:hover {
    background-color: #4A4A4A;
    transform: translateY(-1px);
    box-shadow: 0 2px 6px rgba(0,0,0,0.4);
}

.error-container {
    position: fixed;
    bottom: 24px;
    left: 50%;
    transform: translateX(-50%);
    background: #5C1130;
    color: #FFB3B3;
    padding: 16px 24px;
    border-radius: 16px;
    display: none;
    z-index: 10001;
    box-shadow: 0 4px 12px rgba(0,0,0,0.3);
    animation: slideUp 0.3s ease;
}

.switch {
    position: relative;
    display: inline-block;
    width: 52px;
    height: 32px;
}

.slider {
    position: absolute;
    cursor: pointer;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    background-color: #4A4458;
    transition: .3s;
    border-radius: 16px;
}

.slider:before {
    position: absolute;
    content: "";
    height: 24px;
    width: 24px;
    left: 4px;
    bottom: 4px;
    background-color: #E6E1E5;
    transition: .3s;
    border-radius: 50%;
}

input:checked + .slider {
    background-color: #D0BCFF;
}

input:checked + .slider:before {
    transform: translateX(20px);
    background-color: #1C1B1F;
}

.config-file-container {
    margin: 24px 0;
    padding: 24px;
    border: 2px solid #555555;
    border-radius: 20px;
    background-color: #4A4A4A;
    transition: all 0.2s ease;
}

.config-file-container:hover {
    border-color: #D0BCFF;
    box-shadow: 0 2px 8px rgba(0,0,0,0.3);
}

.config-file-container input[type="file"] {
    max-width: 100%;
    width: auto;
    box-sizing: border-box;
    padding: 12px;
    border: 2px dashed #4A4458;
    border-radius: 16px;
    background-color: #332D41;
    color: #E6E1E5;
    cursor: pointer;
    transition: all 0.2s ease;
}

.config-file-container input[type="file"]::-webkit-file-upload-button {
    padding: 8px 16px;
    margin-right: 12px;
    background-color: #404040;
    color: #E6E1E5;
    border: none;
    border-radius: 12px;
    cursor: pointer;
    transition: all 0.2s ease;
}

.config-file-container input[type="file"]::-webkit-file-upload-button:hover {
    background-color: #4A4A4A;
}

.file-hint {
    margin-top: 12px;
    font-size: 14px;
    color: #CAC4D0;
    line-height: 1.5;
}

.config-control-btn {
    margin-top: 20px;
    padding: 12px 28px;
    background-color: #404040;
    color: #E6E1E5;
    border: none;
    border-radius: 24px;
    cursor: pointer;
    font-size: 14px;
    font-weight: 500;
    transition: all 0.2s ease;
    display: inline-flex;
    align-items: center;
    justify-content: center;
}

.config-control-btn:hover {
    background-color: #4A4A4A;
    transform: translateY(-1px);
    box-shadow: 0 2px 8px rgba(0,0,0,0.4);
}

.theme-toggle-container {
    margin: 24px 0;
    display: flex;
    flex-direction: column;
    gap: 16px;
}

#theme-select {
    width: 100%;
    padding: 12px 16px;
    font-size: 1.2rem;
    background-color: #404040;
    color: #FFFFFF;
    border: 2px solid #555555;
    border-radius: 12px;
    cursor: pointer;
    appearance: none;
    -webkit-appearance: none;
    background-image: url("data:image/svg+xml;charset=UTF-8,%3csvg xmlns='http://www.w3.org/2000/svg' viewBox='0 0 24 24' fill='none' stroke='white' stroke-width='2' stroke-linecap='round' stroke-linejoin='round'%3e%3cpolyline points='6 9 12 15 18 9'%3e%3c/polyline%3e%3c/svg%3e");
    background-repeat: no-repeat;
    background-position: right 16px center;
    background-size: 16px;
}

#theme-select:hover {
    background-color: #4A4A4A;
    border-color: #666666;
}

#theme-select:focus {
    outline: none;
    border-color: #D0BCFF;
    background-color: #4A4A4A;
}

#theme-select option {
    background-color: #404040;
    color: #FFFFFF;
    padding: 12px;
}

#theme-select option:hover,
#theme-select option:focus {
    background-color: #4A4A4A;
}

.theme-toggle-container label {
    font-size: 16px;
    color: #E6E1E5;
    margin-bottom: 8px;
}

.reminder-overlay {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background-color: rgba(0, 0, 0, 0.95);
    display: flex;
    align-items: center;
    justify-content: center;
    opacity: 0;
    visibility: hidden;
    transition: all 0.5s ease;
    backdrop-filter: blur(8px);
    z-index: 9999;
}

.reminder-overlay.show {
    opacity: 1;
    visibility: visible;
}

.reminder-content {
    text-align: center;
    animation: fadeIn 0.5s ease;
}

.reminder-title {
    font-size: 5rem;
    color: white;
    margin-bottom: 2rem;
}

.reminder-subtitle {
    font-size: 3rem;
    color: #FFD60A;
}

@keyframes fadeIn {
    from {
        opacity: 0;
        transform: translateY(-20px);
    }
    to {
        opacity: 1;
        transform: translateY(0);
    }
}

.info-section {
    position: relative;
}

.info-toggle-btn {
    position: absolute;
    right: 0;
    top: 0;
    background-color: #404040;
    color: #E6E1E5;
    border: none;
    border-radius: 50%;
    width: 48px;
    height: 48px;
    cursor: pointer;
    display: flex;
    align-items: center;
    justify-content: center;
    transition: all 0.2s ease;
    z-index: 2;
}

.info-toggle-btn:hover {
    background-color: #4A4A4A;
    transform: translateY(-1px);
}

.info-toggle-btn .material-icons {
    font-size: 24px;
}

.paper-count-container {
    margin: 20px 0;
}

.paper-input-group {
    display: flex;
    align-items: center;
    gap: 10px;
    margin: 10px 0;
    font-size: 2.5rem;
}

.count-control {
    display: flex;
    align-items: center;
    gap: 5px;
}

.count-control input {
    width: 60px;
    padding: 5px;
    font-size: 2rem;
    text-align: center;
    background-color: #212121;
    color: #E6E1E5;
    border: 2px solid #404040;
    border-radius: 8px;
}

.count-btn {
    display: flex;
    align-items: center;
    justify-content: center;
    width: 36px;
    height: 36px;
    border: none;
    border-radius: 50%;
    background-color: #404040;
    color: #E6E1E5;
    cursor: pointer;
    transition: all 0.2s ease;
}

.count-btn:hover {
    background-color: #4A4A4A;
    transform: translateY(-1px);
}

.count-btn .material-icons {
    font-size: 20px;
}

.count-btn-group {
    display: flex;
    flex-direction: column;
    gap: 2px;
    margin-right: 8px;
}

.count-control {
    display: flex;
    align-items: center;
    gap: 5px;
}

.count-btn {
    width: 24px;
    height: 24px;
    padding: 0;
    display: flex;
    align-items: center;
    justify-content: center;
}

.count-btn .material-icons {
    font-size: 16px;
}