1. A non-transitory computer-readable medium embodying a program executable in at least one computing device comprising at least one hardware processor, the program comprising code that, when executed by the at least one computing device, causes the at least one computing device to: access an email resource requested by a client device from at least one email service; identify a resource rule specifying a condition for which the client device is authorized to access the email resource, the resource rule being identified based at least in part on a device state of the client device; determine whether the email resource satisfies the resource rule based at least in part on a stringency level associated with the resource rule, the stringency level being increased or reduced based at least in part on the device state; responsive to the email resource failing to satisfy the resource rule, modify the email resource causing the email resource to satisfy the resource rule; and responsive to the email resource, as modified, satisfying the resource rule, authorize the client device to access the email resource.