new.css lite version without fonts and minification https://newcss.net/

lighter.css

:root {
    --text-color: #1a1a1a;
    --light-grey-color: #f6f8fa;
    --grey-color: #e5e7eb;
    --link-color: #0070f3;
    --link-accent-color: #0366d6;
    --light-cyan-color: #79ffe1;
    --dark-cyan-color: #0c4047;
}

* {
    margin: 0;
    padding: 0;
}

address,
area,
article,
aside,
audio,
blockquote,
datalist,
details,
dl,
fieldset,
figure,
form,
input,
iframe,
img,
meter,
nav,
ol,
optgroup,
option,
output,
p,
pre,
progress,
ruby,
section,
table,
textarea,
ul,
video {
    margin-bottom: 1rem;
}

html,
input,
select,
button {
    font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, Oxygen, Ubuntu, Cantarell, 'Open Sans', 'Helvetica Neue', sans-serif, "Apple Color Emoji", "Segoe UI Emoji", "Segoe UI Symbol";
}

body {
    margin: 0 auto;
    max-width: 750px;
    padding: 2rem;
    border-radius: 6px;
    overflow-x: hidden;
    color: var(--text-color);
    font-size: 1.03rem;
    line-height: 1.5;
}

::selection {
    background: var(--light-cyan-color);
    color: var(--dark-cyan-color);
}

p {
    margin-bottom: 1rem;
}

h1,
h2,
h3,
h4,
h5,
h6 {
    line-height: 1;
    color: var(--nc-tx-1);
    padding-top: .875rem;
}

h1,
h2,
h3 {
    color: var(--nc-tx-1);
    padding-bottom: 2px;
    margin-bottom: 8px;
    border-bottom: 1px solid var(--light-grey-color);
}

h4,
h5,
h6 {
    margin-bottom: .3rem;
}

h1 {
    font-size: 2.25rem;
}

h2 {
    font-size: 1.85rem;
}

h3 {
    font-size: 1.55rem;
}

h4 {
    font-size: 1.25rem;
}

h5 {
    font-size: 1rem;
}

h6 {
    font-size: .875rem;
}

a {
    color: var(--link-color);
}

a:hover {
    color: var(--link-accent-color);
}

abbr:hover {
    cursor: help;
}

blockquote {
    padding: 1.5rem;
    background: var(--light-grey-color);
    border-left: 5px solid var(--grey-color);
}

abbr {
    cursor: help;
}

blockquote :last-child {
    padding-bottom: 0;
    margin-bottom: 0;
}

header {
    background: var(--light-grey-color);
    border-bottom: 1px solid var(--grey-color);
    padding: 2rem 1.5rem;
    margin: -2rem calc(0px - (50vw - 50%)) 2rem;
    padding-left: calc(50vw - 50%);
    padding-right: calc(50vw - 50%);
}

header h1,
header h2,
header h3 {
    padding-bottom: 0;
    border-bottom: 0;
}

header> :first-child {
    margin-top: 0;
    padding-top: 0;
}

header> :last-child {
    margin-bottom: 0;
}

a button,
button,
input[type="submit"],
input[type="reset"],
input[type="button"] {
    font-size: 1rem;
    display: inline-block;
    padding: 6px 12px;
    text-align: center;
    text-decoration: none;
    white-space: nowrap;
    background: var(--link-color);
    border: 0;
    border-radius: 4px;
    box-sizing: border-box;
    cursor: pointer;
}

a button[disabled],
button[disabled],
input[type="submit"][disabled],
input[type="reset"][disabled],
input[type="button"][disabled] {
    cursor: default;
    opacity: .5;
    cursor: not-allowed;
}

a button:focus,
a button:hover,
button:focus,
button:hover,
input[type="submit"]:focus,
input[type="submit"]:hover,
input[type="reset"]:focus,
input[type="reset"]:hover,
input[type="button"]:focus,
input[type="button"]:hover {
    background: var(--link-accent-color);
}

code,
pre,
kbd,
samp {
    font-family: Consolas, monaco, 'Ubuntu Mono', 'Liberation Mono', 'Courier New', Courier, monospace;
}

code,
samp,
kbd,
pre {
    background: var(--light-grey-color);
    border: 1px solid var(--grey-color);
    border-radius: 4px;
    padding: 3px 6px;
    font-size: .9rem;
}

kbd {
    border-bottom: 3px solid var(--grey-color);
}

pre {
    padding: 1rem 1.4rem;
    max-width: 100%;
    overflow: auto;
}

pre code {
    background: inherit;
    font-size: inherit;
    color: inherit;
    border: 0;
    padding: 0;
    margin: 0;
}

code pre {
    display: inline;
    background: inherit;
    font-size: inherit;
    color: inherit;
    border: 0;
    padding: 0;
    margin: 0;
}

details {
    padding: .6rem 1rem;
    background: var(--light-grey-color);
    border: 1px solid var(--grey-color);
    border-radius: 4px;
}

summary {
    cursor: pointer;
    font-weight: 700;
}

details[open] {
    padding-bottom: .75rem;
}

details[open] summary {
    margin-bottom: 6px;
}

details[open]>:last-child {
    margin-bottom: 0;
}

dt {
    font-weight: 700;
}

dd::before {
    content: '→ ';
}

hr {
    border: 0;
    border-bottom: 1px solid var(--grey-color);
    margin: 1rem auto;
}

fieldset {
    margin-top: 1rem;
    padding: 2rem;
    border: 1px solid var(--grey-color);
    border-radius: 4px;
}

legend {
    padding: auto .5rem;
}

table {
    border-collapse: collapse;
    width: 100%;
}

td,
th {
    border: 1px solid var(--grey-color);
    text-align: left;
    padding: .5rem;
}

th {
    background: var(--light-grey-color);
}

tr:nth-child(even) {
    background: var(--light-grey-color);
}

table caption {
    font-weight: 700;
    margin-bottom: .5rem;
}

textarea {
    max-width: 100%;
}

ol,
ul {
    padding-left: 2rem;
}

li {
    margin-top: .4rem;
}

ul ul,
ol ul,
ul ol,
ol ol {
    margin-bottom: 0;
}

mark {
    padding: 3px 6px;
    background: var(--light-cyan-color);
    color: var(--dark-cyan-color);
}

textarea,
select,
input {
    padding: 6px 12px;
    margin-bottom: .5rem;
    background: var(--light-grey-color);
    color: var(--text-color);
    border: 1px solid var(--light-grey-color);
    border-radius: 4px;
    box-shadow: none;
    box-sizing: border-box;
}

textarea:focus,
select:focus,
input[type]:focus {
    border: 1px solid var(--grey-color);
    outline: 0;
}

img {
    max-width: 100%;
}