pretix_cgo/src/pretix/static/pretixpresale/scss/_calendar.scss

.table-calendar, .week-calendar {
  td, th {
    width: 14.29%;
  }
  h3 {
    margin: 0;
    font-size: 16px;
  }
  a.event {
    display: block;
    background: $brand-primary;
    color: white;
    border-radius: $border-radius-large;
    padding: 3px 5px;
    margin-top: 3px;
    font-size: 12px;

    &.continued {
      background: #888;
      opacity: 0.8;
      &:hover {
        background: darken(#888, 15%);
        opacity: 1;
      }
    }

    &.soon {
      opacity: 0.8;
      &:hover {
        opacity: 1;
      }
    }

    &.over {
      opacity: 0.8;
      background: #888;
      &:hover {
        opacity: 1;
        background: darken(#888, 15%);
      }
    }

    &.available, {
      background: $brand-success;

      &:hover {
        background: darken($brand-success, 15%);
      }
    }

    &.reserved, &.soldout, {
      background: $brand-danger;

      &:hover {
        background: darken($brand-danger, 15%);
      }
    }

    .event-name {
      font-weight: bold;
      display: block;
    }
    .event-time, .event-status {
      display: block;
    }

    &:hover {
      text-decoration: none;
      background: darken($brand-primary, 15%);
    }
  }
  .selected-day {
    display: none;
  }
}
.week-calendar {
  .weekday {
    margin-bottom: 15px;
  }
  h3 {
    margin-bottom: 5px;
    font-weight: bold;
    cursor: pointer;
  }
  h3 .fa::before {
    content: $fa-var-caret-right;
  }
  details[open] h3 .fa::before {
    content: $fa-var-caret-down;
  }
  .events {
    overflow: hidden;  /* required for smooth toggle animation */
  }
  .no-events {
    display: none;
  }
}
@media (min-width: $screen-md-min) {
  .week-calendar {
    display: flex;
    flex-direction: row;

    details[open] summary {
      cursor: default;
      pointer-events: none;
      h3 .fa {
        display: none;
      }
    }

    .weekday {
      flex: 1;
      margin: 0 5px;
    }
    .weekday:first-child {
      margin-left: 0;
    }
    .weekday:last-child {
      margin-right: 0;
    }
    .no-events {
      display: block;
    }
  }
}
@media (max-width: $screen-xs-max) {
  .table-calendar .day .events {
    display: none;
  }
  .table-calendar td.day.has-events {
    background: $brand-primary;
    cursor: pointer;
    color: white;
  }
  .table-calendar td.day.has-events:hover {
    background: darken($brand-primary, 15%);
  }
}
#monthselform .row {
  margin: 0 -15px;
}
#monthselform .row > div {
  margin-bottom: 15px;
}
@media(min-width: $screen-sm-min) {
   .select-calendar-week-short {
     max-width: 50%;
   }
}