Twig Templating If statement (Unexpected tag name error)

Question

Sorry if this is a really obvious question, I'm new to Twig and Craft. I'm getting the following error: Unexpected tag name "offset" (expecting closing tag for the "if" tag defined near line 54)

Can anyone tell me what is wrong with my code?

<div class="box alt container">
{% set offset = true %}
{% if offset %}
<section class="feature left">
    {% set caseHero = entry.heroImage.first() %}
    <a href="#" class="image icon fa-signal"><img src='{{caseHero.url}}' alt="" /></a>
    <div class="content">
        <h3>{{entry.title}}</h3>
        <p>{{entry.description}}</p>
    </div>
</section>
    {% offset = false %}
{% else %}
<section class="feature left">
    {% set caseHero = entry.heroImage.first() %}
    <a href="#" class="image icon fa-signal"><img src='{{caseHero.url}}' alt="" /></a>
    <div class="content">
        <h3>{{entry.title}}</h3>
        <p>{{entry.description}}</p>
    </div>
</section>
    {% offset = true %}
{% endif %}

Answer 1

It seems like you want to set offset to false after your first section.

To do this correctly you would need to use set like this:

{% set offset = false %}

Checkout the documentation to set a variable

Answer 2

The problem line is this one:

{% offset = true %}

It needs to be:

{% set offset = true %}

I think there are a couple of occurrences.