CSS cubic-bezier timing functions – courtesy of https://github.com/jaukia/easie

_timing-functions.scss

// CSS cubic-bezier timing functions
// @type cubic-bezier

$ease-in-quad:      cubic-bezier(0.550,  0.085, 0.680, 0.530);
$ease-in-cubic:     cubic-bezier(0.550,  0.055, 0.675, 0.190);
$ease-in-quart:     cubic-bezier(0.895,  0.030, 0.685, 0.220);
$ease-in-quint:     cubic-bezier(0.755,  0.050, 0.855, 0.060);
$ease-in-sine:      cubic-bezier(0.470,  0.000, 0.745, 0.715);
$ease-in-expo:      cubic-bezier(0.950,  0.050, 0.795, 0.035);
$ease-in-circ:      cubic-bezier(0.600,  0.040, 0.980, 0.335);
$ease-in-back:      cubic-bezier(0.600, -0.280, 0.735, 0.045);

$ease-out-quad:     cubic-bezier(0.250,  0.460, 0.450, 0.940);
$ease-out-cubic:    cubic-bezier(0.215,  0.610, 0.355, 1.000);
$ease-out-quart:    cubic-bezier(0.165,  0.840, 0.440, 1.000);
$ease-out-quint:    cubic-bezier(0.230,  1.000, 0.320, 1.000);
$ease-out-sine:     cubic-bezier(0.390,  0.575, 0.565, 1.000);
$ease-out-expo:     cubic-bezier(0.190,  1.000, 0.220, 1.000);
$ease-out-circ:     cubic-bezier(0.075,  0.820, 0.165, 1.000);
$ease-out-back:     cubic-bezier(0.175,  0.885, 0.320, 1.275);

$ease-in-out-quad:  cubic-bezier(0.455,  0.030, 0.515, 0.955);
$ease-in-out-cubic: cubic-bezier(0.645,  0.045, 0.355, 1.000);
$ease-in-out-quart: cubic-bezier(0.770,  0.000, 0.175, 1.000);
$ease-in-out-quint: cubic-bezier(0.860,  0.000, 0.070, 1.000);
$ease-in-out-sine:  cubic-bezier(0.445,  0.050, 0.550, 0.950);
$ease-in-out-expo:  cubic-bezier(1.000,  0.000, 0.000, 1.000);
$ease-in-out-circ:  cubic-bezier(0.785,  0.135, 0.150, 0.860);
$ease-in-out-back:  cubic-bezier(0.680, -0.550, 0.265, 1.550);