message: Banner: clean up css
  remove unnecessary specific banner styles
  reorder styles for specificity
diff: .Banner {
  color: var(--text_primary);
  margin: 12px 0;
  + padding: 0 16px;
  }
  .Banner__in {
  display: flex;
  position: relative;
  + padding: 12px;
  + background-color: var(--content_tint_background);
  + border-radius: 8px;
  overflow: hidden;
  }
  }
  .Banner__before {
  - margin-right: 12px;
  + margin-right: 8px;
  }
  .Banner__content {
  position: absolute;
  left: 0;
  top: 0;
  - width: 100%;
  - height: 100%;
  z-index: 1;
  }
  +.Banner__bg,
  .Banner__bg > * {
  width: 100%;
  height: 100%;
  align-items: center;
  justify-content: center;
  color: var(--icon_secondary);
  - z-index: 2;
  + z-index: 3;
  }
  .Banner__actions {
  margin-bottom: -6px;
  }
  -/**
  - * Size "s"
  - */
  -
  -.Banner--sz-s .Banner__subheader:not(:first-child),
  -.Banner--sz-s .Banner__text:not(:first-child) {
  +.Banner__subheader:not(:first-child),
  +.Banner__text:not(:first-child) {
  margin-top: 2px;
  }
  -/**
  - * Size "m"
  - */
  -
  -.Banner--sz-m .Banner__subheader:not(:first-child),
  -.Banner--sz-m .Banner__text:not(:first-child) {
  - margin-top: 4px;
  -}
  -
  /**
  * Mode "tint"
  */
  -.Banner--md-tint .Banner__in {
  - background-color: var(--content_tint_background);
  -}
  -
  -.Banner--md-tint .Banner__in {
  - padding: 12px;
  -}
  -
  -/**
  - * Mode "tint" and size "s"
  - */
  -
  -.Banner--md-tint.Banner--sz-s .Banner__before {
  - margin-right: 8px;
  -}
  -
  -.Banner--md-tint.Banner--sz-s .Banner__content {
  +.Banner--md-tint .Banner__content {
  padding-left: 4px;
  }
  -/**
  - * Mode "tint" and size "m"
  - */
  -
  -.Banner--md-tint.Banner--sz-m .Banner__in {
  - padding: 16px;
  -}
  -
  /**
  * Mode "image"
  */
  z-index: 2;
  }
  -.Banner--md-image .Banner__dismiss {
  - color: var(--white);
  +.Banner--md-image .Banner__before {
  + margin-right: 12px;
  }
  +.Banner--md-image .Banner__dismiss,
  .Banner--inverted {
  color: var(--white);
  }
  }
  /**
  - * Mode "tint" and size "m"
  + * Size "m"
  */
  -
  -.Banner--md-image.Banner--sz-m .Banner__in {
  +.Banner--sz-m .Banner__in {
  padding: 16px;
  }
  +.Banner--sz-m .Banner__subheader:not(:first-child),
  +.Banner--sz-m .Banner__text:not(:first-child) {
  + margin-top: 4px;
  +}
  +
  /**
  * iOS
  */
  .Banner--ios.Banner--md-image .Banner__dismiss {
  color: var(--icon_tertiary);
  }
  -
  -/**
  - * Android & VKCOM
  - */
  -
  -.Banner--android,
  -.Banner--vkcom {
  - padding: 0 16px;
  -}
  -
  -.Banner--android .Banner__in,
  -.Banner--vkcom .Banner__in {
  - border-radius: 8px;
  -}
  