Jason Melgoza jasonmelgoza

Advanced SCSS

Or, 16 cool things you may not have known your stylesheets could do. I'd rather have kept it to a nice round number like 10, but they just kept coming. Sorry.

I've been using SCSS/SASS for most of my styling work since 2009, and I'm a huge fan of Compass (by the great @chriseppstein). It really helped many of us through the darkest cross-browser crap. Even though browsers are increasingly playing nice with CSS, another problem has become very topical: managing the complexity in stylesheets as our in-browser apps get larger and larger. SCSS is an indispensable tool for dealing with this.

This isn't an introduction to the language by a long shot; many things probably won't make sense unless you have some SCSS under your belt already. That said, if you're not yet comfy with the basics, check out the aweso

OS X Screencast to animated GIF

This gist shows how to create a GIF screencast using only free OS X tools: QuickTime, ffmpeg, and gifsicle.

Instructions

To capture the video (filesize: 19MB), using the free "QuickTime Player" application:

Bootstrap Sample template

How to make faster scroll effects?

Avoid too many reflows (the browser to recalculate everything)
Use advanced CSS3 for graphic card rendering
Precalculate sizes and positions

Beware of reflows

The reflow appens as many times as there are frames per seconds. It recalculate all positions that change in order to diplay them. Basically, when you scroll you execute a function where you move things between two reflows. But there are functions that triggers reflows such as jQuery offset, scroll... So there are two things to take care about when you dynamically change objects in javascript to avoid too many reflows:

	var margin = 15;

	S.cfga({
	"defaultToCurrentScreen" : true,
	"secondsBetweenRepeat" : 0.1,
	"checkDefaultsOnLoad" : true,
	"focusCheckWidthMax" : 3000
	});

	// Create Operations

	/* The show classes */
	.show-for-small /* Visible up to 768px */
	.show-for-medium-down /* Visible from 1280px down */
	.show-for-medium /* Visible between 768px and 1280px */
	.show-for-medium-up /* Visible from 1280px up */
	.show-for-large-down /* Visible from 1440px down */
	.show-for-large /* Visible between 1280px and 1440px */
	.show-for-large-up /* Visible from 1440px up */

	/* The hide classes */

	gifify() {
	if [[ -n "$1" ]]; then
	if [[ $2 == '--good' ]]; then
	ffmpeg -i $1 -r 10 -vcodec png out-static-%05d.png
	time convert -verbose +dither -layers Optimize -resize 600x600\> out-static*.png GIF:- \| gifsicle --colors 128 --delay=5 --loop --optimize=3 --multifile - > $1.gif
	rm out-static*.png
	else
	ffmpeg -i $1 -s 600x400 -pix_fmt rgb24 -r 10 -f gif - \| gifsicle --optimize=3 --delay=3 > $1.gif
	fi
	else

	class PdfMerger

	def merge(pdf_paths, destination)

	first_pdf_path = pdf_paths.delete_at(0)

	Prawn::Document.generate(destination, :template => first_pdf_path) do \|pdf\|

	pdf_paths.each do \|pdf_path\|
	pdf.go_to_page(pdf.page_count)

	<!DOCTYPE html>
	<html>
	<head>
	<meta charset="utf-8">
	<title>{{Title}}</title>
	<meta name="viewport" content="width=device-width, initial-scale=1">
	<style>
	body {
	font-family: Helvetica Neue, Helvetica, Arial;
	font-size: 14px;