elseif needs to be single word tag/keyword and expression shouldn’t have parenthesis same as if expression.
http://twig.sensiolabs.org/doc/tags/if.html
<body
{% if page|default('login') == 'login' %}
class="login"
{% elseif page == 'other' %}
class="login"
{% else %}
class="noclass"
{% endif %}>
</body>