:root {
    --s0: #f8fafc;
    --s1: #f1f5f9;
    --s2: #e2e8f0;
    --s3: #cbd5e1;
    --s4: #94a3b8;
    --s5: #64748b;
    --s6: #475569;
    --s7: #334155;
    --s8: #1e293b;
    --s9: #0f172a;
    --s10: #020617;
    /* --s11: rgb(7, 10, 19); */
    --s11: #001;
}

:root {
    --bg-color: var(--s11);
    --text-color: var(--s1);
    --text-color-p: var(--s4);
}

*,
*::before,
*::after {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

html {
    font-size: 16px;
    /* color-scheme: dark light; */
    scroll-behavior: smooth;
    scroll-padding-top: 2rem;
    -webkit-font-smoothing: antialiased;
    -moz-osx-font-smoothing: grayscale;
}

body {
    min-height: 100vh;
    min-height: 100svh;
    /* small viewport height: overwrite a use on newer browsers*/
    /* compensate reduced height on mobile browsers */
    width: 100vw;
    overflow-x: hidden;
    background-color: var(--bg-color);
    color: var(--text-color);
    transition: all 0.5s ease;
}

#root {
    isolation: isolate;
    /* nothing goes beyond root element when working with z-index */
    /* without isolation, elements with negative z-index will be hidden by the background color  of the parent*/
}

/* responsive content */
img,
picture,
svg,
video {
    display: block;
    /* block => covers full width if not explicitly defined */
    /* inline => covers max-content width even if explicitly defined */
    /* inline-block => covers only the explicitly defined width but will allow other elements to stack alongside it on the same row (easy hack to switch from flex-direction: row to flex-direction: column) */
    max-width: 100%;
}

a,
input,
select,
textarea,
button {
    font: inherit;
    color: inherit;
    line-height: inherit;
}

p,
h1,
h2,
h3,
h4,
h5,
h6 {
    overflow-wrap: break-word;
    /* avoid text overflows (CSS is Awesome) */
}

h1,
h2,
h3,
h4,
h5,
h6 {
    text-wrap: balance;
}

p {
    max-width: 100ch;
    text-wrap: pretty;
    hyphens: auto;
    /* solve the problem of orphan isolation */
}

::selection {
    background-color: cyan;
    color: black;
}

/* entire scrollbar */
::-webkit-scrollbar {
    width: 10px;
    /* vertical */
    height: 10px;
    /* horizontal */
}

/* scrollbar track */
::-webkit-scrollbar-track {
    background: transparent;
}

/* scrollbar thumb */
::-webkit-scrollbar-thumb {
    background: var(--s1);
    border-radius: 1rem;
}

/* scrollbar thumb on hover */
/* ::-webkit-scrollbar-thumb:hover {
    background: #444;
} */

/* use inset a a substitute of top right bottom left in absolute positioning */

h1 {
    font-size: 4rem;
    color: var(--s1);
}

h2 {
    font-size: 2rem;
    color: var(--s2);
}

h3 {
    font-size: 1.75rem;
    color: var(--s3);
}

h4 {
    font-size: 1.5rem;
    color: var(--s4);
}

p {
    font-size: 1rem;
    color: var(--s4);
    line-height: 1.5;
}

.btn {
    font-size: 1.5rem;
    padding: .5em 1em;
    border-radius: 4em;
    border: none;
    outline: none;
    font-family: 'Clash Display', system-ui;
    font-weight: 600;
    transition: all 0.3s ease;
    color: var(--s10);
    background-image: linear-gradient(#aaa, azure);
    box-shadow: 0px .25em 0px slategray;
}

.btn:active {
    transform: translateY(.5em);
    box-shadow: 0px 0px 0px slategray;
}