<apex:pageBlockSection title="Contact Role" id="pbs" collapsible="false">
             <apex:inputField styleClass="slds-lookup__search-input" value="{!contactRole.Account__c}"  />
             <apex:inputField styleClass="slds-lookup__search-input" value="{!contactRole.Contact__c}" />
             <apex:inputField value="{!contactRole.Role__c}" required="true"  />
             <apex:inputField value="{!contactRole.ActiveStatus__c}" />
             <apex:inputField value="{!contactRole.Start_Date__c}" />
             <apex:inputField value="{!contactRole.End_Date__c}" />
             <apex:inputField value="{!contactRole.Primary__c}" />
        </apex:pageBlockSection>

<apex:inputField styleClass="slds-lookup__search-input" value="{!contactRole.Contact__c}" />