WordPress Custom Search for Post Type, Meta Key & Taxonomies

Yesterday I asked this question but I didn’t get answer. So I think people don’t understand my question. So Here I edit and explain it in details:

My WordPress have a post type Products

I Products have 2 custom field name Color & Location The Products also have enabled Category & Tags Field.

Now my search from look like this:

<form action="/" method="get">
    <label>Keyword: </label> <input type="text" name="s" placeholder="Keyword"> <br />
    <label>Color: </label> <input type="text" name="color" placeholder="Color"> <br />
    <label>Location: </label> <input type="text" name="location" placeholder="Location"> <br />
    <label>Category: </label> <select name="category"><option value="1">Shirt</option><option value="1">Pant</option><option value="1">Pajama</option></select> <br />
    <label>Tags: </label> <input type="text" name="location" placeholder="Tags"> <br />
    <input type="Submit" value="Search">
</form>

So If someone type shirt in keyword field and write Red in color field, then Search Result will show posts by shirt in title & red from meta_key from any category..

If people leave blank keyword field and input Red & Bangladesh in Color & Location field then only posts will come that contain Red & Bangladesh Meta value from any category.

So People can filter search by color, location, category & Tags.

I tried using this kind of search query in search.php but not work.

    <?php
        $color = $_GET['color'];
        $location = $_GET['location'];
        $args = array(
                'post_type' => 'any',
                'meta_query' => array(
                'relation' => 'AND',
                    array(
                        'key' => color,
                        'value' => $color,
                    ),
                    array(
                        'key' => location,
                        'value' => $location,
                    )
            )
         );  
    ?>
      <h3>Your Search For <?php echo $color; ?> <?php if(!empty($location) OR isset($location) OR $location !== NULL ){echo '';} else { echo "and".$location; } ?></h3>

    <?php $query = new WP_Query( $args ); if(have_posts()) : ?>
    <?php while(have_posts()) : the_post() ?>

                <h3><?php the_title(); ?></h3>
                <?php if(get_field('color')): ?>
                    <b>Color:</b> <?php the_field('color'); ?>
                <?php endif; ?>
                <?php if(get_field('location')): ?>
                    <b>Location:</b> <?php the_field('location'); ?>
                <?php endif; ?>

  <?php endwhile; ?>

  <?php else: ?>
        <p class="notice_msg"><?php _e( 'Sorry, but nothing matched your search criteria.'); ?></p>
  <?php endif; ?>

Please help me someone. I really need this Help.

Thank you