#content{
  z-index: 999 !important;
}
.back-to-top {
/* Basic styling */
background-color: rgba(255,255,255, 0.5);
border: 2px solid currentColor;
border-radius: 0.5em;
display: inline-block;
padding: 0.1em;

/* Position at the bottom right of the viyewport */
position: fixed;
inset: auto 1rem 1rem auto;
}

.back-to-top:is(:link, :visited) {
/* Instead of the link color, use the text color */
color: currentColor;
text-decoration: none;
}

.back-to-top span {
/* Hide text accessibly */
clip: rect(0 0 0 0);
clip-path: inset(50%);
height: 1px;
overflow: hidden;
position: absolute;
white-space: nowrap;
width: 1px;
}

.back-to-top {
--yellow: rgba(255,65,150, 0.5);
--white: rgba(65,216,255,0.4);
background-image: linear-gradient(var(--yellow), var(--white));
}

.back-to-top {
background-image: linear-gradient(var(--yellow) 0% 50%, var(--white) 50% 100%);
}

.back-to-top {
background-image: linear-gradient(var(--yellow) 0% var(--progress), var(--white) var(--progress) 100%);
}

@keyframes progress {
0% {
--progress: 0%;
}

100% {
--progress: 100%;
}
}

.back-to-top {
--yellow: rgba(255,65,150, 0.5);
--white: rgba(65,216,255,0.4);

background-image: linear-gradient(var(--yellow) 0% var(--progress), var(--white) var(--progress) 100%);
/* ... */
animation: progress linear;
animation-timeline: scroll();
}

@property --progress {
syntax: '<length-percentage>';
inherits: false;
initial-value: 0%;
}


@property --angle {
syntax: '<angle>';
inherits: true;
initial-value: -90deg;
}

@keyframes progress {
0% {
--progress: 0%;
--angle: 0deg;
}

8% {
--angle: -90deg;
}

100% {
--progress: 100%;
}
}

.back-to-top svg {
/* … */
transform: rotate(var(--angle));
}

@supports not (animation-timeline: scroll()) {
.back-to-top {
background: var(--yellow);
}
}


@media(prefers-reduced-motion: no-preference) {
html {
scroll-behavior: smooth;
}
}