Hello.
My markup works ok on the desktop but when I test on mobile, the sitelookup field expands if I select an account with a long name. Then the screen becomes unusable (can't press the Save button or read the other fields. Is there an SLDS class to prevent a field from resizing to fit the selected name?

<lightning:layout >
        <lightning:layoutItem padding="around-small" size="{!v.screenSize}" class="slds-align_absolute-center">
            <lightning:card iconName="standard:opportunity" title="New Opportunity">
                <form class="slds-form--stacked">         
                    
                    <lightning:input aura:id="oppform" label="Opportunity Name"
                                     name="oppname"
                                     value="{!v.newOpp.Name}"
                                     required="true"
                                     class="slds-p-horizontal_x-small"/>
                    
                    <lightning:input type="number" aura:id="oppform" label="Revenue"
                                     name="revenue"
                                     value="{!v.newOpp.Amount}"
                                     required="true"
                                     class="slds-p-horizontal_x-small"/>
                    
                    <lightning:input type="date" aura:id="oppform" label="Estimated Close Date"
                                     name="closedate"
                                     value="{!v.newOpp.CloseDate}"
                                     required="true"
                                     class="slds-p-horizontal_x-small"/>
                    
                    <c:strike_lookup aura:id="sitelookup"                                     
                                     value="{!v.siteID}"
                                     label="Site"
                                     object="Account"
                                     searchField="Name"
                                     placeholder="Select a site"
                                     iconName="standard:account"
                                     filter="{!v.filter}"
                                     order="Name"
                                     limit="5"
                                     loadingMessage="Loading..."
                                     errorMessage="Invalid input"
                                     class="slds-p-horizontal_x-small "
                                     required="true"/>
                    
                    <p>    <div class="slds-p-horizontal_x-small" > 
                        <i><small>   Enter a site. You may enter more sites after saving. Do not enter a contractor or EPC.</small></i></div></p>
                    <br/>
                    
                    <c:strike_lookup aura:id="ownerlookup" 
                                     value="{!v.newOpp.AccountId}"
                                     label="Owner" 
                                     object="Account"
                                     searchField="Name"
                                     placeholder="Select an owner"
                                     iconName="standard:account"
                                     filter="type = 'owner'"
                                     order="Name"
                                     limit="5"
                                     loadingMessage="Loading..."
                                     errorMessage="Invalid input"
                                     class="slds-p-horizontal_x-small"
                                     required="true"/>
                    
                    <p>    <div class="slds-p-horizontal_x-small" > 
                        <i><small>   Site owner. Do not enter a contractor or EPC.</small></i></div></p>
                    <br/>
                    
                    <c:strike_lookup aura:id="contractorlookup"                                     
                                     value="{!v.contractorID}"
                                     label="Contractor" 
                                     object="Account"
                                     searchField="Name"
                                     placeholder="Select a contractor"
                                     iconName="standard:account"
                                     filter="type = 'contractor'"                                     
                                     order="Name"
                                     limit="5"
                                     loadingMessage="Loading..."
                                     errorMessage="Invalid input"
                                     class="slds-p-horizontal_x-small"/>
                    
                    <p>    <div class="slds-p-horizontal_x-small" > 
                        <i><small>   (Optional) CG or EPC. If bidding to multiple contractors, you may enter more contractors after saving.</small></i></div></p>                    
                    
                    <p>     <div class="slds-text-color_error" >     <ui:outputText value="{!v.Err}" /></div></p>
                   
                    <lightning:button label="Save"
                                      class="slds-m-around_small"
                                      variant="brand"
                                      onclick="{!c.clickCreate}"/>
                </form>
            </lightning:card>
        </lightning:layoutItem>
    </lightning:layout>

 

doInit: function(component) {
        var userAgent = navigator.userAgent || navigator.vendor || window.opera;
        if(userAgent.match( /iPad/i ) || userAgent.match( /iPhone/i ) || userAgent.match( /iPod/i ) || userAgent.match( /Android/i )) {
            component.set("v.screenSize", 12);
        } else component.set("v.screenSize", 6);
    },

Thanks
Denise