:root {
    --spacing: 8px;
}

* {
    box-sizing: border-box;
}

/* TOP-LEVEL */

html {
    font-family: Cabin, sans-serif;
    font-size: 16px;
    font-display: swap;
    color: #212121;
}

body {
    margin: 0;
}

pre {
    font-family: "Fira Code", monospace;
}

h1,
h2,
h3,
h4,
h5,
h6 {
    margin: 0;
}

input {
    padding: 0.25rem;
}

.hidden {
    display: none;
}

.wrapper {
    margin: 0 auto;
    width: 100%;
    padding: 0 var(--spacing);
}

/* HEADER */

header {
    padding: calc(var(--spacing) * 2) 0;
}

.app-title {
    text-align: center;
}

/* MAIN */

.app-subtitle {
    margin: var(--spacing) 0;
}

.main-ctn {
    display: flex;
    flex-direction: column;
}

ul.tree {
    margin: 0;
}

ul.tree li {
    margin: 0.25rem 0 0.25rem 1rem;
    list-style-type: disc;
}

.controls {
    display: none;
}

.btn-link:hover {
    background-color: #eeeeee;
}

.output-tree-ctn {
    padding: var(--spacing);
    border-radius: 5px;
    background-color: #eeeeee;
}