app/views/devise/sessions/new.html.erb
<%= title "Sign in" %>
<div class="row" id="form-login">
<div class="span6 offset2 signup-title">
<h1>Log in into your account </h1>
</div>
<div class="span4 offset2 social-form">
<p class="lead"> Login with a service </p>
<%= render "devise/shared/social" %>
</div>
<div class="span5">
<div class="email-form">
<p class="lead"> Login with your email </p>
<%= simple_form_for(resource, as: resource_name, url: session_path(resource_name)) do |f| %>
<div class="form-inputs">
<%= f.input :email, label: false, placeholder: "Email", autofocus: true %>
<%= f.input :password, label: false, placeholder: "Password" %>
<%= f.input :remember_me, as: :boolean if devise_mapping.rememberable? %>
</div>
<div>
<%= f.button :submit, value: "Log in to your account" ,class: "btn btn-large btn-success" %>
</div>
<% end %>
<%= render "devise/shared/links" %>
</div>
</div>
</div>