how to write conditional classes in liquid because of whitespace

shopify-whitespace.liquid

<main class="giftcard {% if gift_card.expired or gift_card.enabled != true %} giftcard--disabled{% endif %}">

{%- if gift_card.expired != true and gift_card.expires_on and gift_card.enabled -%}
  <span class="giftcard-tag giftcard-tag--active">{{ 'gift_cards.issued.active' | t: expiry: gift_card_expiry_date }}</span>
{%- endif -%}