diff --git a/browser.html b/browser.html
deleted file mode 100644
index 43c3599..0000000
--- a/browser.html
+++ /dev/null
@@ -1,182 +0,0 @@
-<!DOCTYPE html>
-<html lang="en">
-  <head>
-    <meta charset="UTF-8" />
-    <meta name="viewport" content="width=device-width, initial-scale=1.0" />
-    <title>Demo</title>
-    <style>
-      .status.RIGHT {
-        color: forestgreen;
-      }
-      .status.ERROR {
-        color: red;
-      }
-    </style>
-  </head>
-  <body>
-    <ul id="test"></ul>
-    <script src="./dist/colorfuls.js"></script>
-    <script>
-      var docFrag = document.createDocumentFragment()
-
-      function it(ruleTitle, fn) {
-        var liEl = document.createElement('li')
-        var status = fn()
-
-        liEl.innerHTML =
-          '<span class="name">' + ruleTitle + ' -> </span><span class="status ' + status + '">' + status + '</span>'
-
-        docFrag.appendChild(liEl)
-      }
-
-      var assert = {
-        strictEqual: function (a, b) {
-          return a === b ? 'RIGHT' : 'ERROR'
-        }
-      }
-
-      // hex rgb rgba
-      it('HEX "#5CB1F8" should be RGB "rgb(92, 177, 248)"', function () {
-        return assert.strictEqual(Colorfuls.hex2Rgb('#5CB1F8'), 'rgb(92, 177, 248)')
-      })
-      it('HEX "#5CB1F8" should be HSLA "hsl(207, 92%, 67%)"', function () {
-        return assert.strictEqual(Colorfuls.hex2Hsl('#5CB1F8'), 'hsl(207, 92%, 67%)')
-      })
-      it('RGB "rgb(92, 177, 248)" should be HEX "#5CB1F8"', function () {
-        return assert.strictEqual(Colorfuls.rgb2Hex('rgb(92, 177, 248)'), '#5CB1F8')
-      })
-      it('RGB "rgb(92, 177, 248)" should be HSL "hsl(207, 92%, 67%)"', function () {
-        return assert.strictEqual(Colorfuls.rgb2Hsl('rgb(92, 177, 248)'), 'hsl(207, 92%, 67%)')
-      })
-      it('HSL "hsl(207, 92%, 67%)" should be RGB "rgb(93, 179, 248)"', function () {
-        return assert.strictEqual(Colorfuls.hsl2Rgb('hsl(207, 92%, 67%)'), 'rgb(93, 179, 248)')
-      })
-      it('HSL "hsl(207, 92%, 67%)" should be HEX "#5DB3F8"', function () {
-        return assert.strictEqual(Colorfuls.hsl2Hex('hsl(207, 92%, 67%)'), '#5DB3F8')
-      })
-
-      // rgba hexa hsla
-      it('HEXA "#5CB1F8FF" should be RGBA "rgba(92, 177, 248, 1)"', function () {
-        return assert.strictEqual(Colorfuls.hexa2Rgba('#5CB1F8FF'), 'rgba(92, 177, 248, 1)')
-      })
-      it('HEXA "#5CB1F8FF" should be HSLA "hsla(207, 92%, 67%, 1)"', function () {
-        return assert.strictEqual(Colorfuls.hexa2Hsla('#5CB1F8FF'), 'hsla(207, 92%, 67%, 1)')
-      })
-      it('RGBA "rgba(92, 177, 248, 1)" should be HEXA "#5CB1F8FF"', function () {
-        return assert.strictEqual(Colorfuls.rgba2Hexa('rgba(92, 177, 248, 1)'), '#5CB1F8FF')
-      })
-      it('RGBA "rgba(92, 177, 248, 1)" should be HSLA "hsla(207, 92%, 67%, 1)"', function () {
-        return assert.strictEqual(Colorfuls.rgba2Hsla('rgba(92, 177, 248, 1)'), 'hsla(207, 92%, 67%, 1)')
-      })
-      it('HSLA "hsla(207, 92%, 67%, 1)" should be RGBA "rgba(93, 179, 248, 1)"', function () {
-        return assert.strictEqual(Colorfuls.hsla2Rgba('hsla(207, 92%, 67%, 1)'), 'rgba(93, 179, 248, 1)')
-      })
-      it('HSLA "hsla(207, 92%, 67%, 1)" should be HEXA "#5DB3F8FF"', function () {
-        return assert.strictEqual(Colorfuls.hsla2Hexa('hsla(207, 92%, 67%, 1)'), '#5DB3F8FF')
-      })
-
-      it('grayscale(#5CBF54) -> #959595', function () {
-        return assert.strictEqual(Colorfuls.grayscale('#5CBF54').toHex(), '#959595')
-      })
-      it('complement(#7FFFD4): #7FFFD4 -> #FF7FAA', function () {
-        return assert.strictEqual(Colorfuls.complement('#7FFFD4').toHex(), '#FF7FAA')
-      })
-      it('invert(rgb(0, 100, 255)): -> rgb(255, 155, 0)', function () {
-        return assert.strictEqual(Colorfuls.invert('rgb(0, 100, 255)').toRgb(), 'rgb(255, 155, 0)')
-      })
-      it('isDark(rgb(255, 155, 0)): -> true', function () {
-        return assert.strictEqual(Colorfuls.isDark('rgb(255, 155, 0)'), false)
-      })
-      it('isLight(rgb(255, 155, 0)): -> false', function () {
-        return assert.strictEqual(Colorfuls.isLight('rgb(255, 155, 0)'), true)
-      })
-
-      // rgba
-      it('rgba.fade(): rgba(10, 10, 10, 0.8) -> rgba(10, 10, 10, 0.4)', function () {
-        return assert.strictEqual(Colorfuls.Color('rgba(10, 10, 10, 0.8)').fade(0.5).toRgba(), 'rgba(10, 10, 10, 0.4)')
-      })
-      it('rgba.opaque(): rgba(10, 10, 10, 0.8) -> rgba(10, 10, 10, 1)', function () {
-        return assert.strictEqual(Colorfuls.Color('rgba(10, 10, 10, 0.8)').opaque(0.5).toRgba(), 'rgba(10, 10, 10, 1)')
-      })
-
-      // hsla
-      it('hsla.rotate(180): hsl(60, 20%, 20%) -> hsl(240, 20%, 20%)', function () {
-        return assert.strictEqual(Colorfuls.Color('hsl(60, 20%, 20%)').rotate(180).toHsl(), 'hsl(240, 20%, 20%)')
-      })
-      it('hsla.rotate(-90): hsl(60, 20%, 20%) -> hsl(330, 20%, 20%)', function () {
-        return assert.strictEqual(Colorfuls.Color('hsl(60, 20%, 20%)').rotate(-90).toHsl(), 'hsl(330, 20%, 20%)')
-      })
-      it('hsla.saturate(0.5): hsl(100, 50%, 50%) -> hsl(100, 75%, 50%)', function () {
-        return assert.strictEqual(Colorfuls.Color('hsl(100, 50%, 50%)').saturate(0.5).toHsl(), 'hsl(100, 75%, 50%)')
-      })
-      it('hsla.desaturate(0.5): hsl(100, 50%, 50%) -> hsl(100, 25%, 50%)', function () {
-        return assert.strictEqual(Colorfuls.Color('hsl(100, 50%, 50%)').desaturate(0.5).toHsl(), 'hsl(100, 25%, 50%)')
-      })
-      it('hsla.lighten(0.5): hsl(100, 50%, 50%) -> hsl(100, 50%, 75%)', function () {
-        return assert.strictEqual(Colorfuls.Color('hsl(100, 50%, 50%)').lighten(0.5).toHsl(), 'hsl(100, 50%, 75%)')
-      })
-      it('hsla.darken(0.5): hsl(100, 50%, 50%) -> hsl(100, 50%, 25%)', function () {
-        return assert.strictEqual(Colorfuls.Color('hsl(100, 50%, 50%)').darken(0.5).toHsl(), 'hsl(100, 50%, 25%)')
-      })
-
-      it('mix(#f00, #00f) -> #800080', function () {
-        return assert.strictEqual(Colorfuls.mix('#f00', '#00f').toHex(), '#800080')
-      })
-      it('mix(#f00, #00f, 25%) -> #3F00BF', function () {
-        return assert.strictEqual(Colorfuls.mix('#f00', '#00f', '25%').toHex(), '#4000BF')
-      })
-      it('mix(rgba(255, 0, 0, 0.5), #00f) -> rgba(64, 0, 191, 0.75)', function () {
-        return assert.strictEqual(Colorfuls.mix('rgba(255, 0, 0, 0.5)', '#00f').toRgba(), 'rgba(64, 0, 191, 0.75)')
-      })
-
-      it('gradient(#000, #fff).step(0.5) -> #808080', function () {
-        return assert.strictEqual(Colorfuls.gradient('#000', '#fff').step(0.5).toHex(), '#808080')
-      })
-      it('gradient(#000, #fff).steps(3) -> #000000, #808080, #FFFFFF', function () {
-        return assert.strictEqual(
-          Colorfuls.gradient('#000', '#fff').steps(3).toHexs().join(', '),
-          '#000000, #808080, #FFFFFF'
-        )
-      })
-      it('linearGradient(#000, #fff, #000).steps(3) -> #000000, #FFFFFF, #000000', function () {
-        return assert.strictEqual(
-          Colorfuls.linearGradient('#000', '#fff', '#000').steps(3).toHexs().join(', '),
-          '#000000, #FFFFFF, #000000'
-        )
-      })
-      it('linearGradient(#000, #fff, #000).steps(5) -> #000000, #808080, #FFFFFF, #808080, #000000', function () {
-        return assert.strictEqual(
-          Colorfuls.linearGradient('#000', '#fff', '#000').steps(5).toHexs().join(', '),
-          '#000000, #808080, #FFFFFF, #808080, #000000'
-        )
-      })
-      it('linearGradient(#000, #111, #222, #333, [#444, 0.4], #fff).steps(11) -> #000000, #111111, #222222, #333333, #444444, #636363, #828282, #A2A2A2, #C1C1C1, #E0E0E0, #FFFFFF', function () {
-        return assert.strictEqual(
-          Colorfuls.linearGradient('#000', '#111', '#222', '#333', ['#444', '40%'], '#fff')
-            .steps(11)
-            .toHexs()
-            .join(', '),
-          '#000000, #111111, #222222, #333333, #444444, #636363, #828282, #A2A2A2, #C1C1C1, #E0E0E0, #FFFFFF'
-        )
-      })
-      it('linearGradient(rgba(0, 0, 0, 0), rgba(0, 0, 0, 0.2), rgba(0, 0, 0, 0.4), rgba(0, 0, 0, 0.6), rgba(0, 0, 0, 0.8), rgba(0, 0, 0, 1)).steps(5) -> rgba(0, 0, 0, 0), rgba(0, 0, 0, 0.25), rgba(0, 0, 0, 0.5), rgba(0, 0, 0, 0.75), rgba(0, 0, 0, 1)', function () {
-        return assert.strictEqual(
-          Colorfuls.linearGradient(
-            'rgba(0, 0, 0, 0)',
-            'rgba(0, 0, 0, 0.2)',
-            'rgba(0, 0, 0, 0.4)',
-            'rgba(0, 0, 0, 0.6)',
-            'rgba(0, 0, 0, 0.8)',
-            'rgba(0, 0, 0, 1)'
-          )
-            .steps(5)
-            .toRgbas()
-            .join(', '),
-          'rgba(0, 0, 0, 0), rgba(0, 0, 0, 0.25), rgba(0, 0, 0, 0.5), rgba(0, 0, 0, 0.75), rgba(0, 0, 0, 1)'
-        )
-      })
-
-      document.getElementById('test').appendChild(docFrag)
-    </script>
-  </body>
-</html>
