/* =============================================================================
   BUAMS AI new-ui — FORMS
   Spec: /frontend_design.md §F.2, §F.3

   ONE field contract for every control, so validation and spacing never drift:

     <div class="bui-field">
       <label class="bui-label" for="x">Label <span class="bui-required">*</span></label>
       <input id="x" class="bui-input" aria-describedby="x-help x-error">
       <p class="bui-help"  id="x-help">Help text.</p>
       <p class="bui-error" id="x-error" role="alert" hidden></p>
     </div>

   Error state carries THREE signals — border colour, a ⚠ glyph, and the message
   text. Colour is never the only signal (spec §F.3): ~8% of men have a colour
   vision deficiency, and printed pages may drop background colour entirely.
   ============================================================================= */

/* ── Field wrapper ────────────────────────────────────────────────────────── */
.bui-field {
  margin-bottom: var(--bui-space-5);
}

.bui-field:last-child {
  margin-bottom: 0;
}

/* ── Label ────────────────────────────────────────────────────────────────
   Sentence case, NOT uppercase (spec §C.1). Every control gets a real label;
   placeholder-as-label is prohibited (spec §F.2). */
.bui-label {
  display: block;
  margin-bottom: var(--bui-space-2);
  font-size: var(--bui-text-label);
  font-weight: var(--bui-fw-semibold);
  line-height: var(--bui-lh-snug);
  color: var(--bui-ink-900);
}

.bui-required {
  color: var(--bui-danger);
  font-weight: var(--bui-fw-heavy);
}

.bui-label-optional {
  margin-left: var(--bui-space-1);
  font-size: var(--bui-text-xs);
  font-weight: var(--bui-fw-regular);
  color: var(--bui-ink-500);
}

/* Label row with a trailing action (e.g. "Password  … Forgot?") */
.bui-label-row {
  display: flex;
  align-items: baseline;
  justify-content: space-between;
  gap: var(--bui-space-3);
  margin-bottom: var(--bui-space-2);
}

.bui-label-row .bui-label {
  margin-bottom: 0;
}

/* ── Controls ─────────────────────────────────────────────────────────────── */
.bui-input,
.bui-select,
.bui-textarea {
  display: block;
  width: 100%;
  min-height: var(--bui-control-h);
  padding: var(--bui-space-2) var(--bui-space-3);
  background: var(--bui-surface);
  border: 1px solid var(--bui-line-strong);
  border-radius: var(--bui-radius-md);
  font-family: var(--bui-font);
  font-size: var(--bui-text-body);
  line-height: var(--bui-lh-normal);
  color: var(--bui-ink-900);
  transition: border-color var(--bui-transition),
              box-shadow var(--bui-transition),
              background-color var(--bui-transition);
  appearance: none;
}

.bui-textarea {
  min-height: 96px;
  resize: vertical;
}

.bui-select {
  padding-right: var(--bui-space-10);
  background-image: url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' width='14' height='14' viewBox='0 0 16 16' fill='none' stroke='%23667A70' stroke-width='2' stroke-linecap='round'%3E%3Cpath d='M4 6l4 4 4-4'/%3E%3C/svg%3E");
  background-repeat: no-repeat;
  background-position: right var(--bui-space-3) center;
  cursor: pointer;
}

.bui-input::placeholder,
.bui-textarea::placeholder {
  color: var(--bui-ink-300);
}

/* Focus: 2px brand border PLUS a 3px ring (spec §F.2) */
.bui-input:focus,
.bui-select:focus,
.bui-textarea:focus {
  outline: none;
  border-color: var(--bui-primary-700);
  box-shadow: var(--bui-focus-ring);
}

.bui-input:disabled,
.bui-select:disabled,
.bui-textarea:disabled,
.bui-input[readonly] {
  background: var(--bui-disabled-bg);
  border-color: var(--bui-line);
  color: var(--bui-ink-500);
  cursor: not-allowed;
}

/* ── Help + error text ────────────────────────────────────────────────────── */
.bui-help {
  margin-top: var(--bui-space-2);
  font-size: var(--bui-text-xs);
  line-height: var(--bui-lh-snug);
  color: var(--bui-ink-500);
}

.bui-error {
  display: flex;
  align-items: flex-start;
  gap: var(--bui-space-1);
  margin-top: var(--bui-space-2);
  font-size: var(--bui-text-xs);
  font-weight: var(--bui-fw-medium);
  line-height: var(--bui-lh-snug);
  color: var(--bui-danger);
}

/* Signal 2 of 3: a glyph, so the state survives greyscale and print */
.bui-error::before {
  content: '\26A0';
  flex-shrink: 0;
  font-size: .95em;
  line-height: 1.35;
}

.bui-success-text {
  display: flex;
  align-items: flex-start;
  gap: var(--bui-space-1);
  margin-top: var(--bui-space-2);
  font-size: var(--bui-text-xs);
  font-weight: var(--bui-fw-medium);
  color: var(--bui-success);
}

.bui-success-text::before {
  content: '\2713';
  flex-shrink: 0;
  font-weight: var(--bui-fw-heavy);
}

/* ── Validation states ────────────────────────────────────────────────────── */
.bui-input.is-invalid,
.bui-select.is-invalid,
.bui-textarea.is-invalid {
  border-color: var(--bui-danger);
  background-color: var(--bui-danger-bg);
}

.bui-input.is-invalid:focus,
.bui-select.is-invalid:focus,
.bui-textarea.is-invalid:focus {
  border-color: var(--bui-danger);
  box-shadow: 0 0 0 3px rgba(180, 35, 24, .14);
}

/* Success is used ONLY where confirmation is meaningful (e.g. subdomain
   availability) — never on every field (spec §F.2). */
.bui-input.is-valid,
.bui-select.is-valid {
  border-color: var(--bui-success);
}

.bui-input.is-valid:focus {
  border-color: var(--bui-success);
  box-shadow: 0 0 0 3px rgba(21, 127, 79, .14);
}

/* ── Input group (prefix / suffix addon) ──────────────────────────────────── */
.bui-input-group {
  display: flex;
  align-items: stretch;
  width: 100%;
}

.bui-input-group > .bui-input {
  flex: 1 1 auto;
  min-width: 0;
}

.bui-addon {
  display: inline-flex;
  align-items: center;
  flex-shrink: 0;
  padding: 0 var(--bui-space-3);
  background: var(--bui-surface-2);
  border: 1px solid var(--bui-line-strong);
  font-size: var(--bui-text-sm);
  color: var(--bui-ink-500);
  white-space: nowrap;
}

.bui-input-group > .bui-addon:first-child {
  border-right: 0;
  border-radius: var(--bui-radius-md) 0 0 var(--bui-radius-md);
}

.bui-input-group > .bui-addon:last-child {
  border-left: 0;
  border-radius: 0 var(--bui-radius-md) var(--bui-radius-md) 0;
}

.bui-input-group > .bui-input:not(:first-child) {
  border-top-left-radius: 0;
  border-bottom-left-radius: 0;
}

.bui-input-group > .bui-input:not(:last-child) {
  border-top-right-radius: 0;
  border-bottom-right-radius: 0;
}

/* The focus ring must sit above the adjoining addon border */
.bui-input-group > .bui-input:focus {
  position: relative;
  z-index: 2;
}

/* Below sm a long suffix (".buams.com") would squeeze the input to nothing,
   so the group stacks and the addon becomes a full-width footer row. */
@media (max-width: 400px) {
  .bui-input-group-wrap {
    flex-wrap: wrap;
  }

  .bui-input-group-wrap > .bui-input {
    flex: 1 1 100%;
    border-radius: var(--bui-radius-md) var(--bui-radius-md) 0 0;
  }

  .bui-input-group-wrap > .bui-addon:last-child {
    flex: 1 1 100%;
    justify-content: center;
    border-top: 0;
    border-left: 1px solid var(--bui-line-strong);
    border-radius: 0 0 var(--bui-radius-md) var(--bui-radius-md);
  }
}

/* ── Password field with visibility toggle ───────────────────────────────── */
.bui-password {
  position: relative;
  display: flex;
  align-items: stretch;
}

.bui-password > .bui-input {
  padding-right: var(--bui-space-12);
}

.bui-password-toggle {
  position: absolute;
  top: 0;
  right: 0;
  display: flex;
  align-items: center;
  justify-content: center;
  width: var(--bui-space-12);
  height: 100%;
  padding: 0;
  background: none;
  border: 0;
  border-radius: 0 var(--bui-radius-md) var(--bui-radius-md) 0;
  color: var(--bui-ink-500);
  cursor: pointer;
  transition: color var(--bui-transition);
}

.bui-password-toggle:hover {
  color: var(--bui-primary-700);
}

.bui-password-toggle:focus-visible {
  outline: 2px solid var(--bui-primary-700);
  outline-offset: -2px;
  color: var(--bui-primary-700);
}

.bui-password-toggle .bi {
  font-size: 1.05rem;
  line-height: 1;
}

/* ── Password requirement checklist ──────────────────────────────────────── */
.bui-requirements {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: var(--bui-space-1) var(--bui-space-3);
  margin-top: var(--bui-space-3);
  padding: 0;
  list-style: none;
}

.bui-requirement {
  display: flex;
  align-items: center;
  gap: var(--bui-space-1);
  font-size: var(--bui-text-xs);
  line-height: var(--bui-lh-snug);
  color: var(--bui-ink-500);
  transition: color var(--bui-transition);
}

/* Glyph changes as well as colour, so the met/unmet distinction is not
   colour-only (spec §F.3) */
.bui-requirement::before {
  content: '\25CB';
  flex-shrink: 0;
  font-size: .9em;
}

.bui-requirement.is-met {
  color: var(--bui-success);
}

.bui-requirement.is-met::before {
  content: '\2713';
  font-weight: var(--bui-fw-heavy);
}

@media (max-width: 400px) {
  .bui-requirements {
    grid-template-columns: 1fr;
  }
}

/* ── Checkbox / radio ─────────────────────────────────────────────────────── */
.bui-check {
  display: flex;
  align-items: flex-start;
  gap: var(--bui-space-2);
  cursor: pointer;
}

.bui-check-input {
  flex-shrink: 0;
  width: 18px;
  height: 18px;
  /* Optical alignment with the first line of a 15px/1.55 label */
  margin: 2px 0 0;
  background: var(--bui-surface);
  border: 1px solid var(--bui-line-strong);
  border-radius: var(--bui-radius-sm);
  cursor: pointer;
  appearance: none;
  transition: background-color var(--bui-transition),
              border-color var(--bui-transition),
              box-shadow var(--bui-transition);
}

.bui-check-input[type='radio'] {
  border-radius: 50%;
}

.bui-check-input:checked {
  background-color: var(--bui-primary-700);
  border-color: var(--bui-primary-700);
  background-repeat: no-repeat;
  background-position: center;
  background-size: 11px;
  background-image: url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' width='12' height='12' viewBox='0 0 16 16' fill='none' stroke='%23fff' stroke-width='2.6' stroke-linecap='round' stroke-linejoin='round'%3E%3Cpath d='M3 8.5l3.2 3.2L13 5'/%3E%3C/svg%3E");
}

.bui-check-input[type='radio']:checked {
  background-image: none;
  box-shadow: inset 0 0 0 3.5px var(--bui-surface);
}

.bui-check-input:focus-visible {
  outline: none;
  border-color: var(--bui-primary-700);
  box-shadow: var(--bui-focus-ring);
}

.bui-check-input.is-invalid {
  border-color: var(--bui-danger);
}

.bui-check-label {
  font-size: var(--bui-text-sm);
  line-height: var(--bui-lh-normal);
  color: var(--bui-ink-700);
  cursor: pointer;
}

/* Touch: expand the hit area without growing the visual control (spec §H.2) */
@media (hover: none) and (pointer: coarse) {
  .bui-check {
    padding: var(--bui-space-2) 0;
    min-height: var(--bui-touch-min);
    align-items: center;
  }

  .bui-check-input {
    margin-top: 0;
  }
}

/* ── Toggle switch ────────────────────────────────────────────────────────── */
.bui-toggle {
  position: relative;
  flex-shrink: 0;
  width: 40px;
  height: 22px;
  background: var(--bui-line-strong);
  border: 0;
  border-radius: var(--bui-radius-pill);
  cursor: pointer;
  appearance: none;
  transition: background-color var(--bui-transition);
}

.bui-toggle::after {
  content: '';
  position: absolute;
  top: 3px;
  left: 3px;
  width: 16px;
  height: 16px;
  background: #fff;
  border-radius: 50%;
  box-shadow: var(--bui-shadow-xs);
  transition: transform var(--bui-transition);
}

.bui-toggle:checked {
  background: var(--bui-primary-700);
}

.bui-toggle:checked::after {
  transform: translateX(18px);
}

.bui-toggle:focus-visible {
  outline: none;
  box-shadow: var(--bui-focus-ring);
}

/* ── Form sections + rows ─────────────────────────────────────────────────── */
.bui-form-section {
  margin-bottom: var(--bui-space-8);
}

.bui-form-section:last-child {
  margin-bottom: 0;
}

.bui-form-section-title {
  display: flex;
  align-items: center;
  gap: var(--bui-space-2);
  margin-bottom: var(--bui-space-4);
  padding-bottom: var(--bui-space-2);
  border-bottom: 1px solid var(--bui-line);
  font-size: var(--bui-text-overline);
  font-weight: var(--bui-fw-heavy);
  letter-spacing: .08em;
  text-transform: uppercase;
  color: var(--bui-primary-700);
}

.bui-form-section-title .bi {
  font-size: .95rem;
}

/* Multi-column rows collapse to one column below md (spec §H.2) */
.bui-form-row {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 0 var(--bui-space-4);
}

@media (max-width: 767.98px) {
  .bui-form-row {
    grid-template-columns: 1fr;
  }
}

/* Row of inline controls (remember-me + forgot-password) */
.bui-field-inline {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: var(--bui-space-3);
  flex-wrap: wrap;
  margin-bottom: var(--bui-space-5);
}

/* ── Progressive disclosure (e.g. "Have a referral code?") ────────────────── */
.bui-disclosure-toggle {
  display: inline-flex;
  align-items: center;
  gap: var(--bui-space-1);
  padding: 0;
  background: none;
  border: 0;
  font-size: var(--bui-text-sm);
  font-weight: var(--bui-fw-semibold);
  color: var(--bui-primary-700);
  cursor: pointer;
}

.bui-disclosure-toggle:hover {
  color: var(--bui-primary-800);
  text-decoration: underline;
}

.bui-disclosure-toggle:focus-visible {
  outline: 2px solid var(--bui-primary-700);
  outline-offset: 3px;
  border-radius: var(--bui-radius-sm);
}

.bui-disclosure-toggle .bi {
  transition: transform var(--bui-transition);
}

.bui-disclosure-toggle[aria-expanded='true'] .bi {
  transform: rotate(180deg);
}

.bui-disclosure-panel {
  margin-top: var(--bui-space-4);
}

/* ── reCAPTCHA ────────────────────────────────────────────────────────────
   The widget renders at a fixed 304px. Below that it must scale rather than
   push the card into horizontal scroll (spec §H.2). */
.bui-captcha {
  margin-bottom: var(--bui-space-5);
}

.bui-captcha > div {
  max-width: 100%;
}

@media (max-width: 350px) {
  .bui-captcha {
    transform: scale(.88);
    transform-origin: 0 0;
  }
}