discourse/app/assets/stylesheets/common/base/modal.scss

@use "lib/viewport";

html.modal-open {
  // prevents bg scrolling when modal is open
  overflow: hidden;
  scrollbar-gutter: stable;
}

html.keyboard-visible.mobile-view {
  .d-modal {
    max-height: calc(var(--composer-vh, 1dvh) * 100);
    height: calc(var(--composer-vh, 1dvh) * 100);
    bottom: 0;
  }

  .d-modal__container {
    max-height: calc(var(--composer-vh, 1dvh) * 100);
    height: calc(var(--composer-vh, 1dvh) * 100);
  }
}

html:not(.keyboard-visible).mobile-device {
  .d-modal__container {
    padding-bottom: env(safe-area-inset-bottom, 1rem);
  }
}

.d-modal {
  pointer-events: none; // Allow clicks through wrappers so they hit the adjacent backdrop element
  display: flex;
  align-items: center;
  width: 100%;
  height: 100%;
  position: fixed;
  top: 0;
  z-index: z("modal", "content");
  overflow: auto;

  @include viewport.until(sm) {
    align-items: flex-end;
  }

  @include viewport.from(sm) {
    --modal-max-width: 600px;
    --modal-width: 30em; // set in ems to scale with user font-size
    --modal-min-width: 400px;
  }

  &__container {
    display: flex;
    flex-direction: column;
    pointer-events: auto;
    box-sizing: border-box;
    border-radius: var(--d-border-radius);
    margin: 0 auto;
    background-color: var(--secondary);
    box-shadow: var(--shadow-modal);
    max-height: var(--modal-max-height, 80vh); // unset, optional theme utility

    @include viewport.until(sm) {
      // this is a hack to prevent issues on safari with transforms
      position: fixed;
      width: 100%;
      max-width: 100%;
      max-height: calc(var(--composer-vh, 1dvh) * 85);

      &.is-entering {
        @include d-animation(modal-enter-mobile, 250ms, ease);
      }

      &.is-exiting {
        @include d-animation(modal-exit-mobile, 250ms, ease);
      }
    }

    @include viewport.from(sm) {
      max-width: var(--modal-max-width);
      min-width: var(--modal-min-width);
      min-height: var(--modal-min-height); // unset, optional theme utility

      .d-modal.--large & {
        max-width: 800px;
      }

      .d-modal.--max & {
        max-width: 90vw;
      }

      .d-modal.has-search & {
        height: 80vh; // fixed height so the modal doesnt jump when the search results appear/filter
      }

      &.is-entering {
        @include d-animation(
          modal-enter-desktop,
          250ms,
          cubic-bezier(0.4, 0, 0.2, 1)
        );
      }

      &.is-exiting {
        @include d-animation(
          modal-exit-desktop,
          250ms,
          cubic-bezier(0.4, 0, 0.2, 1)
        );
      }
    }
  }

  &__header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 0.5rem;
    border-bottom: 1px solid var(--content-border-color);

    &:not(.--has-primary-action) {
      padding: 0.5rem 0.5rem 0.5rem 1.5rem; // offset for close button padding
    }

    .modal-close {
      margin-left: auto;
      align-self: start;

      .d-icon {
        font-size: var(--font-up-2);
        color: var(--primary-high);
      }

      &:focus-visible {
        .d-icon {
          color: var(--primary);
        }
      }
    }
  }

  .d-modal__primary-action,
  .d-modal__dismiss-action {
    .btn {
      text-transform: capitalize;
    }
  }

  &__title-text {
    font-size: var(--font-up-1-rem);
    line-height: var(--line-height-medium);

    @include viewport.from(sm) {
      font-size: var(--font-up-3);
    }
  }

  &__title-text,
  &__subtitle-text {
    margin: 0;
  }

  &__body {
    overflow-y: auto;
    padding: 1rem 1.5rem;
    box-sizing: border-box;

    &.empty {
      display: none;
    }

    input {
      width: auto;

      &[type="text"],
      &[type="password"],
      &[type="number"] {
        width: 100%;
      }
    }

    textarea {
      width: 100%;

      &:not(.--expandable) {
        height: 80px;
      }
    }

    .password-confirmation {
      display: none;
    }

    section.field {
      padding: 0.25em 0;
      margin-bottom: 5px;

      &.with-items {
        display: flex;
        align-items: flex-start;
      }

      .field-item {
        display: inline-block;
        margin-right: 10px;
      }
    }

    pre code {
      white-space: pre-wrap;
      max-width: 100%;
    }
  }

  &__footer {
    display: flex;
    flex-wrap: wrap;
    align-items: center;
    padding: 1rem 1.5rem;
    border-top: 1px solid var(--content-border-color);
    gap: 0.5rem;

    @include viewport.until(sm) {
      &__footer {
        margin-top: auto;

        .--stacked & {
          flex-direction: column;
          align-items: stretch;
        }
      }
    }
  }

  &__backdrop {
    user-select: none;
    position: fixed;
    top: 0;
    right: 0;
    bottom: 0;
    left: 0;
    z-index: z("modal", "overlay");
    background-color: #000;
    animation: fade 0.3s forwards;

    &.fade {
      opacity: 0;
    }

    @media (prefers-reduced-motion) {
      animation-duration: 0s;
    }

    &.is-exiting {
      @include d-animation(
        backdrop-fade-out,
        250ms,
        cubic-bezier(0.4, 0, 0.2, 1)
      );
    }
  }

  #modal-alert {
    padding-left: 1.5rem;
  }

  .ios-device & {
    &__footer {
      margin-top: auto;
    }
  }

  // fixes modal placement on Android when keyboard is visible
  html.keyboard-visible:not(.ios-device) & {
    height: calc(100% - env(keyboard-inset-height));

    .d-modal__container {
      max-height: 100%;
      min-height: 100%;
      height: 100%;
    }
  }

  pre code {
    white-space: pre-wrap;
    max-width: var(--modal-max-width);
  }

  @include viewport.from(sm) {
    .category-chooser {
      width: 50%;
    }
  }

  .input-hint-text {
    margin-left: 0.5em;
    color: var(--secondary-high);
  }
}

// fade in
@keyframes fade {
  from {
    opacity: 0;
  }

  to {
    opacity: 0.6;
  }
}

// Modal animations
@keyframes modal-enter-desktop {
  from {
    transform: scale(0.7);
    opacity: 0;
  }

  to {
    transform: scale(1);
    opacity: 1;
  }
}

@keyframes modal-exit-desktop {
  from {
    transform: scale(1);
    opacity: 1;
  }

  to {
    transform: scale(0.7);
    opacity: 0;
  }
}

@keyframes modal-enter-mobile {
  from {
    transform: translateY(100%);
  }

  to {
    transform: translateY(0);
  }
}

@keyframes modal-exit-mobile {
  from {
    transform: translateY(0);
  }

  to {
    transform: translateY(100%);
  }
}

@keyframes backdrop-fade-out {
  from {
    opacity: 0.6;
  }

  to {
    opacity: 0;
  }
}