`copy/paste themes in settings > custom css`
lowercase ios black

* {
  text-transform: lowercase;
  font-family: "SF Pro Text", system-ui, "Helvetica Neue", sans-serif;
  font-size: 97%;
  font-weight: 440 !important;
  letter-spacing: -0.01em;
  -webkit-font-smoothing: antialiased;
  text-rendering: geometricprecision;
  color: rgba(255, 255, 255, 0.94);
  background: #000 !important;
}

div {
  font-size: 96%;
  font-weight: 500 !important;
  line-height: 1.26rem;
  text-shadow: 0px 0px 18px rgba(255, 255, 255, 0.1);
  backdrop-filter: blur(4px) saturate(1.01) brightness(0.82);
  -webkit-backdrop-filter: blur(4px) saturate(1.01) brightness(0.82);
  background: rgba(0, 0, 0, 0.88) !important;
}

small {
  opacity: 0.88;
}
lowercase ios look

* {
  text-transform: lowercase;
  font-family: "SF Pro Text", system-ui, "Helvetica Neue", sans-serif;
  font-size: 97%;
  font-weight: 440 !important;
  letter-spacing: -0.01em;
  -webkit-font-smoothing: antialiased;
  text-rendering: geometricprecision;
}

div {
  font-size: 96%;
  font-weight: 500 !important;
  line-height: 1.26rem;
  text-shadow: 0px 0px 22px rgba(255, 255, 255, 0.16);
  backdrop-filter: blur(6px) saturate(1.02);
  -webkit-backdrop-filter: blur(6px) saturate(1.02);
}

small {
  opacity: 0.9;
}
lowercase classic monospace

* {
  font-weight: 400 !important;
  text-transform: lowercase;
  font-family: monospace;
  font-size: 94%;
}
div {
  font-size: 95%;
  font-weight: 600 !important;
  text-shadow: 0px 3px 33px #fff;
}
lowercase modern helvetica

* {
  font-weight: 500 !important;
  text-transform: lowercase;
  font-family: monospace;
  font-size: 100%;
  font-family: "SF Sans", helvetica, system-ui, monospace;
}
div {
  font-size: 96%;
  font-weight: 500 !important;
  line-height: 1.2rem;
  text-shadow: 0px 0px 75px #fff;
}