landing-app/landing/src/app/ui/contact-form.scss

// The gap has to beat the distance from a field to its own error message,
// which Material renders flush underneath it — 0px. At 1.25rem the message
// ended up 6px from the *next* field's label and 0px from its own field, so
// "Falta el nombre" read as the caption of "HORAS POR SEMANA" rather than of
// the field above it. The three lines have to group with the field they belong
// to, which means the space between rows must be visibly larger than the space
// inside one.
.landing-form {
  display: flex;
  flex-direction: column;
  gap: 2rem;
}

.landing-form__kind {
  border: 0;
  margin: 0;
  padding: 0;

  legend {
    padding: 0 0 0.5rem;
    font-weight: 600;
  }
}

.landing-form__row {
  display: grid;
  gap: 1.25rem;

  @media (min-width: 640px) {
    grid-template-columns: repeat(2, minmax(0, 1fr));
  }
}

.landing-form__error {
  margin: 0;
  color: var(--pi-color-warn, #d64545);
}

// The hours field sits inside an @if, and that is what breaks its label.
//
// Angular Material measures an outlined field's floating label once, on init,
// and writes the result to the element as an inline
// `transform: var(--mat-mdc-form-field-label-transform, translateY(-50%) …)`.
// A field created inside a conditional block is measured before it has any
// geometry, so the value it keeps is the unfloated one: the label ends up 5px
// above the wrapper instead of 18, straddling the 2px outline and struck
// through by it.
//
// `@pi/ui` already publishes the right geometry for every other field
// (`translateY(-3rem) scale(1)`, a 48px label box), and that rule matches this
// one too — it simply loses to the inline style. `!important` is what beats an
// inline declaration, and it is restating the library's own values, not
// inventing new ones.
:host ::ng-deep .pi-field.pi-form-field__number {
  .mdc-notched-outline .mdc-floating-label {
    height: var(--pi-spacing-xxxx-large) !important;
  }

  .mdc-text-field:not(.mat-form-field-no-animations) .mdc-floating-label {
    transform: translateY(-3rem) scale(1) !important;
  }
}

// Two things the library gets wrong once a field is in a real state.
//
// 1. The label changes shape when you focus it. `@pi/ui` applies the theme's
//    label typography under `:not(.mdc-text-field--focused)`, so text-transform,
//    letter-spacing and weight all fall away the moment the field takes focus:
//    "MENSAJE *" becomes "Mensaje *" in a lighter face, and the label visibly
//    reflows under the cursor. Restated here without that guard. Colour is
//    deliberately left alone — Material tints the label on focus, and that part
//    is wanted.
//
// 2. The focus ring is a stadium on the textarea. Both the notched outline and
//    the gradient ring take their radius from `--pi-theme-field-radius`, which
//    the `alternative` shell sets to 999px. That is right for a 48px-tall input
//    and wrong for a 112px-tall textarea: the two shapes stop coinciding and
//    the field is drawn twice, once in the error colour and once in the
//    gradient, offset from each other. A fixed radius makes them agree again.
:host ::ng-deep {
  .pi-field .mdc-text-field:not(.mdc-text-field--disabled) .mdc-floating-label {
    text-transform: var(--pi-theme-field-label-transform, none);
    letter-spacing: var(--pi-theme-field-label-letter-spacing, normal);
    font-weight: var(--pi-theme-field-label-weight, inherit);
  }

  // A stadium is right for a 48px input and wrong for a 112px textarea, which
  // is all this is now — with the focus ring gone there is no second shape to
  // agree with.
  .pi-field.pi-form-field__textarea {
    --pi-theme-field-radius: 1.25rem;
  }
}

// Error states, which move the form around and read wrong.
//
// 1. Submitting an incomplete form shoved everything below it downwards.
//    Material's subscript strip is 10px tall while a field is valid and 24px
//    once it carries a message, so every errored field grew the form by 14px at
//    once — the fields under the cursor jumped out from under it. Reserving the
//    taller height up front costs 14px of whitespace and buys a form that does
//    not move.
//
// 2. `pi-checkbox` renders its message as an inline span straight after the
//    label, so it ran on as part of the sentence: "Acepto que guardéis mis
//    datos para responderme. Hace falta tu consentimiento". It belongs on its
//    own line, like every other field's message.
:host ::ng-deep {
  .pi-field .mat-mdc-form-field-subscript-wrapper {
    min-height: 1.5rem;
  }

  // Its own line, in space reserved for it. Left in flow it would push the
  // submit button 25px down at the exact moment you press it — the same jump
  // the reserved subscript above removes for the fields.
  .pi-checkbox {
    position: relative;
    padding-bottom: 1.25rem;
  }

  // Nothing in the library styles this class, so the message inherited the
  // body colour and read as ordinary text next to four red ones.
  .pi-checkbox__error {
    display: block;
    position: absolute;
    left: 0;
    bottom: 0;
    color: var(--pi-color-warn);
    // `mat-error` renders the other four at 12px; this one inherited 15px.
    font-size: var(--pi-font-size-x-small, 0.75rem);
  }
}