html {
    margin: 0;
    height: 100vh;
    width: 100vw;
    --background-color: #fff;
    --foreground-color: #000;
    --icon-color: #000;
    --thin-line-color: #ddd;
    --light-btn-color: #efefef;
    --select-open-color: #f3f3f3;
    --brand-color: #654ca3;
    --nav-transition-time: 0.6s;
    --select-open-time: 0.3s;
    --nav-menu-width: min(450px, 70vw);
    --nav-background-color: #dfdfdf;
    --toast-background-color: #fffedf;
    --toast-second-color: #ede1b0;
}

.bold {
    font-weight: bold;
}

.italic {
    font-style: italic;
}

.underline {
    text-decoration: underline;
}

.strikethrough {
    text-decoration: line-through;
}

html, body {
    background: var(--background-color);
    margin: 0;
}

.header-main {
    position: sticky;
    top: 0;
    z-index: 47;
    background: var(--background-color);
    display: flex;
    border-bottom: 1px solid var(--thin-line-color);
    overflow: hidden;
}

.header-main__back-button {
    padding: 2px 15px 0;
    display: flex;
    align-items: center;
}

.header-main__back-button:hover {
    background: var(--light-btn-color);
}

.left-arrow,
.right-arrow {
    display: block;
    margin: 5px;
    width: 20px;
    height: 20px;
    border-top: 2px solid #000;
    border-left: 2px solid #000;
    transform: rotate(-45deg);
    position: relative;
}

.right-arrow {
    transform: rotate(135deg);
}

.left-arrow.with-line::after {
    content: "";
    display: block;
    width: 2px;
    height: 33px;
    background-color: black;
    transform: rotate(-45deg) translate(11px, 4px);
    left: 0;
    top: 0;
}

.header-main__title {
    flex-grow: 1;
    margin: 10px 0;
    padding: 0 0 0 15px;
    text-overflow: ellipsis;
    overflow: hidden;
    white-space: nowrap;
}

.header-main__title:first-letter {
    color: var(--brand-color);
}

.header-main__navbar {
    display: flex;
    align-items: center;
    padding: 0 15px;
    cursor: pointer;
}

.nav-icon {
    width: 40px;
    height: 40px;
    display: flex;
    flex-direction: column;
    justify-content: space-around;
}

.nav-icon>div {
    height: 2px;
    background: var(--foreground-color);
}

.none,
.none *,
.hidden * {
    display: none !important;
}

.hidden,
.loading-container-wrapper.hidden {
    opacity: 0;
    visibility: hidden;
}

.loading-container-wrapper {
    position: fixed;
    z-index: 48;
    width: 100%;
    height: 100%;
    padding-bottom: 80px;
    display: flex;
    align-items: center;
    justify-content: center;
    background-color: #eee;
    transition: visibility var(--nav-transition-time) linear, opacity var(--nav-transition-time) ease;
    opacity: 0.67;
}

.loading-container {
    margin-top: -10%;
}

.loading {
    animation: spin 2s linear infinite;
}

@keyframes spin {
    0% { transform: rotate(0deg); }
    100% { transform: rotate(360deg); }
}