I ttied "Create a Lightning Component to display a single item for your packing list." on trail rail

but i encountered "The campingListItem Lightning Component's attribute tag doesn't exist or its attributes are not set correctly." error 

could anyone give me hint?

my answer for this challenge is following.

<aura:component>
    <aura:attribute name="item" type="Camping_Item__c"/>
    <p>Name:
        <ui:outputText value="{!v.item.Name}"/>
    </p>
    <p>Price:
        <ui:outputCurrency value="{!v.item.Price__c}"/>
    </p>
    <p>Quantity:
        <ui:outputNumber value="{!v.item.Quantity__c}"/>
    </p>
    <p>Packed:
        <ui:outputCheckbox value="{!v.item.Packed__c}"/>
    </p>
</aura:component>
 

I am doing "Create and Edit Lightning Components" on trailhead

even I set follwing in campingHeader.css , could someoen give me hint?

H1.THIS {
    font-size: 18px;
}