HTML (7 - 10 days)
There is no much serious concepts to learn in HTML until HTML5. You need to know which tag is used for which block of element. Forms are some important while learning HTML. A time of 5 days to week days is enough for almost getting an idea of HTML. You need to have another 2 to 3 days for concepts introduced in HTML5.
CSS (8 - 12 days)
This takes a little more time as it is full of different types of styling rules and some interesting concepts like positioning, floating, etc. So give this a time of 6 days to 8 days. Then you need to concentrate on CSS3 properties (Animations, Transformations, etc.) as they are playing an important role in today's web UI design. For this give a time of 2 - 4 days.
Javascript (14 - 21 days)
This is the hero which can change almost anything you had built using the above two. So you need to learn continuously this one but for getting the basics you need atleast 2 weeks to 3 weeks depending upon your speed. After this you can move on some frame works like jQuery, node.js, etc.
So for getting the knowledge of basic front end languages, you need to spend 1 month to 1.5 months. Don't think after doing work for this much of time you will be super hero. No. You need to practice regularly to get able to use the mark up tags and CSS styles. Lastly, For getting expertise you need to learn everyday.
You can spend 2 hours for learning and 1 hour for applying or practising what you had learnt. It's not that you read some thing continuously for two hours and practising it for one hour. Both should be done parallelly with little breaks in between.And another suggestion is after completing one language, then for the second language try to use as much as of first language. I started with this book Learning Web Design.
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