Online Mindfulness-Based Cognitive Therapy in Depressed Sample

The goal of this clinical trial is to evaluate the effectiveness of the online 6-weeks Mindfulness-Based Cognitive Therapy (iMBCT) in depressed sample and compare the guided intervention to an unguided one. The main questions the study aims to answer are: * To what extent completing iMBCT will reduce the severity of depressive symptoms in mild to moderately depressed sample? * What are the differences in participants who completed the program or responded to treatment and those who discontinued it? * What are the differences in treatment effect between two active conditions (guided and unguided iMBCT) and a passive one - waiting-list group? Researchers will compare two iMBCT interventions with a waiting-list group to assess the therapeutic effects of iMBCT on depression, anxiety and other measures related to the mental health.