SELECTOR                EXAMPLE                         DESCRIPTION                                  
.class                  .intro	                        Selects all elements with class="intro"
#id                     #firstname                      Selects the element with id="firstname"         
*                       *                               Selects all elements	                        
element	                p                               Selects all <p> elements	                
element,element         div, p                          Selects all <div> elements and all <p> elements	
element element         div p                           Selects all <p> elements inside <div> elements	
element>element	        div > p	                        Selects all <p> elements where the parent is a <div> element	
element+element	        div + p	                        Selects all <p> elements that are placed immediately after <div> elements	
element1~element2       p ~ ul                          Selects every <ul> element that are preceded by a <p> element	
element:first-child     li:first-child                  Select first li
[attribute^=value]      a[href^="https"]                Selects every <a> element whose href attribute value begins with "https"
[attribute$=value]      a[href$=".pdf"]	                Selects every <a> element whose href attribute value ends with ".pdf"
[attribute*=value]      a[href*="111"]	                Selects every <a> element whose href attribute value contains the substring "111"
::after                 p::after{content:"text"}        Insert something after the content of each <p> element
::before                p::before{src(1.jpg)   }        Insert something before the content of each <p> element