fixed styling issues with network menus

...p/components/analysis-panel/analysis-panel.component.scss

...ft/center-view-inverse/center-view-inverse.component.html

...ft/center-view-inverse/center-view-inverse.component.scss

...oad-button-inverse/download-button-inverse.component.html

...oad-button-inverse/download-button-inverse.component.scss

...etwork/network-menu-left/network-menu-left.component.html

...etwork/network-menu-left/network-menu-left.component.scss

.../network/network-menu-left/network-menu-left.component.ts

...twork/network-menu/center-view/center-view.component.html

...twork/network-menu/center-view/center-view.component.scss

...twork-menu/download-button/download-button.component.html

...mponents/network/network-menu/network-menu.component.html

src/app/components/network/network.component.scss

src/app/components/network/network.component.ts

src/app/pages/explorer-page/explorer-page.component.html

src/app/pages/explorer-page/explorer-page.component.ts

src/app/services/analysis/analysis.service.ts

src/stylesheets/default-theme.css