Cornua aristas

/*! normalize.css v7.0.0 | MIT License | github.com/necolas/normalize.css */
html {line-height: 1.15; -ms-text-size-adjust: 100%; 
  -webkit-text-size-adjust: 100%;}
body {margin: 0;}
article, aside, footer, header, nav, section {display: block;}
h1 {font-size: 2em; margin: 0.67em 0;}
figcaption, figure, main {display: block;}
figure {margin: 1em 40px;}
hr {box-sizing: content-box; height: 0; overflow: visible;}
pre {font-family: monospace, monospace; font-size: 1em;}
a {background-color: transparent; -webkit-text-decoration-skip: objects;}
abbr[title] {border-bottom: none; text-decoration: underline; text-decoration: underline dotted;}
b, strong {font-weight: inherit;}
b, strong {font-weight: bolder;}
code, kbd, samp {font-family: monospace, monospace; font-size: 1em;}
dfn {font-style: italic;}
mark {background-color: #ff0; color: #000;}
small {font-size: 80%;}
sub, sup {font-size: 75%; line-height: 0; position: relative; vertical-align: baseline;}
sub {bottom: -0.25em;}
sup {top: -0.5em;}
audio, video {display: inline-block;}
audio:not([controls]) {display: none; height: 0;}
img {border-style: none;}
svg:not(:root) {overflow: hidden;}
button, input, optgroup, select, textarea {font-family: sans-serif; font-size: 100%; line-height: 1.15; margin: 0;}
button, input {overflow: visible;}
button, select {text-transform: none;}
button, html [type="button"], [type="reset"], [type="submit"] {-webkit-appearance: button;}
button::-moz-focus-inner, [type="button"]::-moz-focus-inner, [type="reset"]::-moz-focus-inner, [type="submit"]::-moz-focus-inner {border-style: none; padding: 0;}
button:-moz-focusring, [type="button"]:-moz-focusring, [type="reset"]:-moz-focusring, [type="submit"]:-moz-focusring {outline: 1px dotted ButtonText;}
fieldset {padding: 0.35em 0.75em 0.625em;}
legend {box-sizing: border-box; color: inherit; display: table; max-width: 100%; padding: 0; white-space: normal;}
progress {display: inline-block; vertical-align: baseline;}
textarea {overflow: auto;}
[type="checkbox"], [type="radio"] {box-sizing: border-box; padding: 0;}
[type="number"]::-webkit-inner-spin-button, [type="number"]::-webkit-outer-spin-button {height: auto;}
[type="search"] {-webkit-appearance: textfield; outline-offset: -2px;}
[type="search"]::-webkit-search-cancel-button, [type="search"]::-webkit-search-decoration {-webkit-appearance: none;}
::-webkit-file-upload-button {-webkit-appearance: button; font: inherit;}
details, menu {display: block;}
summary {display: list-item;}
canvas {display: inline-block;}
template {display: none;}
[hidden] {display: none;}