Wordpress - Wrapping posts in same category with <section> - php

Question

I am trying to use Reveal.js (https://github.com/hakimel/reveal.js/) on WordPress with the Posts being the content per each slide.
I have gotten the post to display properly on the slides, but I am having trouble finding a way to wrap posts that have the same category in a tag.
Basically, My current code looks something like this:
<section class="section chapter-1 ">
</section>
<section class="section chapter-1 ">
</section>
<section class="section chapter-1 ">
</section>
<section class="section chapter-2 ">
</section>
<section class="section chapter-2 ">
</section>
But I need it to look like this:
<section id="category-1">
<section class="section chapter-1 ">
</section>
<section class="section chapter-1 ">
</section>
<section class="section chapter-1 ">
</section>
</section>
<section id="category-2">
<section class="section chapter-2 ">
</section>
<section class="section chapter-2 ">
</section>
</section>
Here is my index.php code:
<div class="reveal content-area">
<div id="content" class="slides site-content" role="main">
<?php if ( have_posts() ) : ?>
<?php /* The loop */ ?>
<?php while ( have_posts() ) : the_post(); ?>
<?php get_template_part( 'content', get_post_format() ); ?>
<?php endwhile; ?>
<?php twentythirteen_paging_nav(); ?>
<?php else : ?>
<?php get_template_part( 'content', 'none' ); ?>
<?php endif; ?>
</div><!-- #content -->
</div><!-- #primary -->
... and so on with more 'chapters' and more categories
If you notice the second code example are grouped and wrapped in a section tag with an ID of the category name.

Answer 1

you could do this, or have an array with categories
<?php
$args = array( 'category' => 1 );
get_posts($args);
?>
<section id="category-1">
<?php
if (have_posts()) : while (have_posts()) : the_post();
?>
<section class="section chapter-<?php the_ID()?> ">
the_content();
</section>
<?php
endwhile; endif;
?>
</section>
<?php
wp_reset_query();
$args = array( 'category' => 2 );
get_posts($args);
<section id="category-2">
if (have_posts()) : while (have_posts()) : the_post();
<section class="section chapter-<?php the_ID()?> ">
the_content();
</section>
endwhile; endif;
</section>
wp_reset_query();
?>