Here is the exact text from the labour law. Hope this helps.

Article 78
The employee is entitled to holidays every year with full salary as following:
1. Three days for Eid Al Fitr.
2. Three days for Eid Al Adha.
3. One day for Qatar Independence Day.
4. Three more days of casual leave decided upon by the employees.
If circumstances require an employee to work on these days, provisions of Article-74 of this law shall come into force.
Article 74
Employees may work additional hours exceeding duty timings prescribed in the previous article. The total work hours per day shall not exceed 10 hours. Employees may exceed these hours to prevent huge losses, accidents, maintenance or to remove effects caused by losses or accidents.
The employer shall pay for additional work hours, an amount not less than the basic salary of the employee, adding an increase of not less than 25 per cent of this salary.
Employees working between 9pm and 3am will be paid basic salary plus an incentive of 50 per cent of this salary, except those who work in shifts.

Aisha-Taweela