.homework-container {
    display: flex;
    gap: 20px;
    padding: 20px;
    min-height: calc(100vh - 120px);
    background-color: #f5f5f5;
}

.homework-sidebar {
    width: 250px;
    background: transparent;
    border-radius: 8px;
    padding: 20px;
}

.course-item {
    display: flex;
    align-items: center;
    gap: 10px;
    padding: 15px 20px;
    background-color: white;
    border-radius: 6px;
    margin-bottom: 15px;
    cursor: pointer;
    transition: all 0.3s ease;
    box-shadow: 0 1px 3px rgba(0,0,0,0.1);
}

.course-item:hover {
    transform: translateY(-1px);
    box-shadow: 0 2px 5px rgba(0,0,0,0.15);
}

.course-item.active {
    background-color: #4a90e2;
    color: white;
}

.course-icon {
    width: 24px;
    height: 24px;
}

.add-course button {
    width: 100%;
    padding: 10px;
    background-color: transparent;
    border: 2px dashed #e0e0e0;
    color: #666;
    border-radius: 6px;
    cursor: pointer;
    transition: all 0.3s ease;
    font-size: 14px;
}

.add-course button:hover {
    background-color: rgba(74,144,226,0.1);
    border-color: #4a90e2;
    color: #4a90e2;
}

.homework-content {
    flex: 1;
    background: white;
    border-radius: 8px;
    padding: 20px;
    box-shadow: 0 2px 4px rgba(0,0,0,0.1);
}

.content-header {
    display: flex;
    justify-content: flex-end;
    margin-bottom: 20px;
}

.edit-btn {
    padding: 4px 12px;
    background-color: #f8f9fa;
    border: none;
    color: #333;
    border-radius: 4px;
    cursor: pointer;
    transition: all 0.3s ease;
    font-size: 14px;
    height: 32px;
}

.edit-btn:hover {
    background-color: #e9ecef;
}

.homework-list {
    display: flex;
    flex-direction: column;
    gap: 15px;
}

.homework-item {
    padding: 15px 20px;
    background-color: #f8f9fa;
    border-radius: 6px;
    cursor: pointer;
    transition: all 0.3s ease;
}

.homework-item:hover {
    background-color: #e9ecef;
}

.homework-item h3 {
    margin: 0;
    font-size: 16px;
    font-weight: 500;
    color: #333;
    padding: 5px;
    border-radius: 4px;
    transition: all 0.3s ease;
}

.homework-item h3.editing {
    background-color: #f8f9fa;
    border: 1px solid #e0e0e0;
    outline: none;
}

.add-homework button {
    width: 100%;
    padding: 15px;
    background-color: transparent;
    border: 2px dashed #e0e0e0;
    color: #666;
    border-radius: 6px;
    cursor: pointer;
    transition: all 0.3s ease;
    font-size: 14px;
}

.add-homework button:hover {
    background-color: rgba(74,144,226,0.1);
    border-color: #4a90e2;
    color: #4a90e2;
}

.hidden {
    display: none !important;
}

.edit-btn.active {
    background-color: #4a90e2;
    color: white;
}

.file-upload-area {
    border: 2px dashed var(--border-color);
    padding: 20px;
    border-radius: 8px;
    text-align: center;
    margin-bottom: 15px;
    transition: all 0.3s ease;
}

.file-upload-area:hover {
    border-color: var(--primary-color);
}

.file-upload-area input[type="file"] {
    display: none;
}

.file-list {
    margin: 15px 0;
    max-height: 200px;
    overflow-y: auto;
}

.file-item {
    display: flex;
    align-items: center;
    justify-content: space-between;
    padding: 8px;
    background: #f8f9fa;
    border-radius: 4px;
    margin-bottom: 8px;
}

.file-item .file-name {
    flex: 1;
    margin-right: 10px;
    overflow: hidden;
    text-overflow: ellipsis;
    white-space: nowrap;
}

.file-item .file-size {
    color: #666;
    font-size: 12px;
    margin-right: 10px;
}

.file-item .remove-file {
    color: #ff4d4f;
    cursor: pointer;
    padding: 4px;
}

.homework-item {
    position: relative;
    padding: 20px;
    border: 1px solid var(--border-color);
    border-radius: 8px;
    margin-bottom: 15px;
    transition: all 0.3s ease;
}

.homework-item:hover {
    box-shadow: 0 2px 8px rgba(0,0,0,0.1);
}

.homework-info {
    display: flex;
    justify-content: space-between;
    align-items: center;
    margin-top: 10px;
    font-size: 14px;
}

.homework-actions {
    display: flex;
    gap: 10px;
    margin-top: 15px;
}

.status {
    padding: 4px 8px;
    border-radius: 4px;
    font-size: 12px;
}

.status.pending {
    background-color: #fff7e6;
    color: #fa8c16;
}

.status.submitted {
    background-color: #f6ffed;
    color: #52c41a;
}