Major CSS design changes

frontend/src/Components/Navbar/Navbar.js

frontend/src/Components/Search/MultiSelectText.jsx

frontend/src/Components/Search/SearchComponent.jsx

frontend/src/Css/Dashboard.css

frontend/src/Css/Form.css

frontend/src/Css/Map.css

frontend/src/Css/Navbar.css

frontend/src/Css/Search.css

frontend/src/Css/Visualiser.css

frontend/src/Css/index.css

frontend/src/Pages/Dashboard/Barchart.jsx

frontend/src/Pages/Dashboard/Dashboard.jsx

frontend/src/Pages/Dashboard/Map.jsx

frontend/src/Pages/Dashboard/Visualiser.jsx