<apex:page showHeader="true" showSidebar="true">
     <apex:include page="LEXPAGENAME"/>
 </apex:page>

function isLightningExperienceOrSalesforce1() {
    return((typeof sforce != 'undefined') && sforce && (!!sforce.one));
}

if( isLightningExperienceOrSalesforce1() ) {
    // Do something for Lightning Experience
}
else {
    // Use classic Visualforce
}

<apex:variable value="{!CONTAINS($CurrentPage.URL, 'lightning.force.com')}" var="isLightningMode"/>
    $CurrentPage.URL = {!$CurrentPage.URL} <br/>
    isLightningMode = {!isLightningMode} <br/>
    <apex:outputpanel layout="none" rendered="{!isLightningMode = false}">
        <!-- Classic UI - Code to display ui in Classic UI mode -->
        this is classic ui
    </apex:outputpanel>

    <apex:outputpanel layout="none" rendered="{!isLightningMode = true}">
        <!-- Lightning mode  - Code to display ui in Lightning mode -->
        this is Lightning mode
    </apex:outputpanel>