/* ==========================================================================
   SenzFusion redesign — css/engage.css
   Design Spec 2.0.0 · Binance.US design system.
   Page layout for partners.html, talk-to-us.html, newsletter.html, legal.html
   and 404.html. Loads after css/base.css. Values come ONLY from tokens.css;
   shared components (cards, forms, buttons, bands) live in base.css.
   Accent-coloured TEXT uses --accent-fg (ink on light, yellow on dark); yellow
   fills use --c-signal. Error copy is never red on light (contrast).
   ========================================================================== */


/* ==========================================================================
   0. Shared engage helpers (form states, actions)
   ========================================================================== */
.form-actions {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: var(--s-3);
}
.form-actions .btn { min-height: var(--control-h); }
@media (max-width: 767px) {
  .form-actions .btn { width: 100%; }
}

/* Busy submit: base.css draws the spinner; drop the arrow while busy */
.btn[aria-busy="true"] .icon { display: none; }

.form-status-body {
  display: grid;
  flex: 1 1 auto;
  gap: var(--s-3);
  justify-items: start;
  min-width: 0;
}
.form-status-body > * { max-width: var(--measure); }
.form-status-title {
  font-weight: var(--fw-semibold);
  line-height: var(--lh-snug);
}
.form-status-actions {
  display: flex;
  flex-wrap: wrap;
  gap: var(--s-3);
}
.form-status > .icon { margin-top: var(--s-half); }
.form-status:focus-visible,
.error-summary:focus-visible { outline-offset: var(--s-half); }
.form-status a:not(.btn):not(.arrow-link),
.form .fine-print a {
  color: var(--link-fg);
  text-decoration-color: var(--link-line);
  text-decoration-thickness: var(--underline);
  text-underline-offset: var(--underline-offset);
}

.field-error .icon { margin-top: calc(-1 * var(--s-half)); }


/* ==========================================================================
   1. Partners
   ========================================================================== */
.partner-models > li {
  display: flex;
  min-width: 0;
}
.partner-model {
  display: flex;
  flex-direction: column;
  gap: var(--s-4);
  width: 100%;
}
.partner-model-key {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  width: var(--s-8);
  height: var(--s-8);
  border: var(--bw) solid var(--c-signal);
  border-radius: var(--r-pill);
  background: var(--c-signal);
  font-family: var(--font-mono);
  font-size: var(--fs-14);
  font-weight: var(--fw-medium);
  line-height: 1;
  color: var(--c-ink);
}
.partner-model-body {
  color: var(--fg-muted);
  margin-bottom: var(--s-4);
}
.partner-model-foot {
  margin-top: auto;
  padding-top: var(--s-4);
  border-top: var(--bw) solid var(--line);
}
@media (min-width: 1024px) {
  .partner-model { padding: var(--s-8); }
}

/* Integration requirements (dark band) */
.requirements {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: var(--s-8);
}
.requirements-list {
  list-style: none;
  margin: 0;
  padding: 0;
  border-top: var(--bw) solid var(--line);
}
.requirements-list li {
  display: grid;
  grid-template-columns: var(--s-12) minmax(0, 1fr);
  gap: var(--s-4);
  align-items: baseline;
  padding-block: var(--s-4);
  border-bottom: var(--bw) solid var(--line);
  color: var(--fg);
}
.requirements-num {
  font-family: var(--font-mono);
  font-size: var(--fs-12);
  font-weight: var(--fw-medium);
  letter-spacing: var(--ls-label);
  font-variant-numeric: tabular-nums;
  color: var(--accent-fg);
}
@media (min-width: 1024px) {
  .requirements {
    grid-template-columns: minmax(0, 5fr) minmax(0, 7fr);
    column-gap: var(--s-12);
    row-gap: var(--s-8);
  }
  .requirements > h2 {
    grid-column: 1;
    grid-row: 1 / span 2;
    align-self: start;
    position: sticky;
    top: calc(var(--header-h) + var(--s-8));
  }
  .requirements-list,
  .requirements-note { grid-column: 2; }
  .requirements-list li {
    padding-block: var(--s-6);
    font-size: var(--fs-18);
  }
}


/* ==========================================================================
   2. Talk to us
   ========================================================================== */
.contact { padding-block: var(--section-pad); }

.contact-layout {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: var(--s-12);
}

.contact-intro {
  display: grid;
  gap: var(--s-6);
  justify-items: start;
  align-content: start;
}
.contact-intro .eyebrow { margin-bottom: calc(-1 * var(--s-2)); }

.contact-direct { margin: 0; }
.contact-email {
  display: inline-flex;
  align-items: center;
  gap: var(--s-3);
  min-height: var(--touch);
  color: var(--fg);
  font-family: var(--font-mono);
  font-size: var(--fs-16);
  font-weight: var(--fw-medium);
  text-decoration: none;
}
.contact-email .icon { color: var(--accent-fg); }
.contact-email span {
  text-decoration: underline;
  text-decoration-color: var(--link-line);
  text-decoration-thickness: var(--underline);
  text-underline-offset: var(--underline-offset);
}
@media (hover: hover) {
  .contact-email:hover span { text-decoration-thickness: var(--underline-hover); }
}

.contact-include {
  display: grid;
  gap: var(--s-3);
  width: 100%;
  max-width: var(--measure-lede);
  margin-top: var(--s-2);
}
.include-list {
  list-style: none;
  margin: 0;
  padding: 0;
  border-top: var(--bw) solid var(--line);
}
.include-list li {
  display: grid;
  grid-template-columns: var(--s-8) minmax(0, 1fr);
  gap: var(--s-3);
  align-items: baseline;
  padding-block: var(--s-3);
  border-bottom: var(--bw) solid var(--line);
  color: var(--fg);
}
.include-num {
  font-family: var(--font-mono);
  font-size: var(--fs-12);
  font-weight: var(--fw-medium);
  letter-spacing: var(--ls-label);
  color: var(--accent-fg);
}

/* Light (snow) form card inside the dark band */
.contact-card {
  position: relative;
  display: grid;
  gap: var(--s-6);
  min-width: 0;
  padding: var(--s-6) var(--s-4);
  border-radius: var(--r-panel);
}
/* Error copy is INK on this light card (Crypto Red fails 4.5:1 on light);
   the red lives on the field border and the alert icon (base.css). */
.contact-card .field-error { color: var(--c-ink); }

@media (min-width: 480px) {
  .contact-card { padding: var(--s-6); }
}
@media (min-width: 768px) {
  .contact-card { padding: var(--s-8); }
}
@media (min-width: 1280px) {
  .contact-card { padding: var(--s-12); }
}

.contact-fields {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: var(--s-6);
}
.contact-fields > * { min-width: 0; }
@media (min-width: 768px) {
  .contact-fields {
    grid-template-columns: repeat(2, minmax(0, 1fr));
    column-gap: var(--s-4);
  }
  .field-full { grid-column: 1 / -1; }
}

/* Engagement model radio group */
.choice-group {
  min-width: 0;
  margin: 0;
  padding: 0;
  border: 0;
}
.choice-group legend {
  padding: 0;
  margin-bottom: var(--s-2);
}
.choice-grid {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: var(--s-2);
}
@media (min-width: 768px) {
  .choice-grid { grid-template-columns: repeat(2, minmax(0, 1fr)); }
}
.choice {
  display: flex;
  align-items: center;
  gap: var(--s-3);
  min-width: 0;
  min-height: var(--control-h);
  padding: var(--s-2) var(--s-input-x);
  border: var(--bw) solid var(--field-line);
  border-radius: var(--r-control);
  background: var(--field-bg);
  color: var(--fg);
  font-family: var(--font-body);
  font-size: var(--fs-14);
  font-weight: var(--fw-semibold);
  letter-spacing: 0;
  line-height: var(--lh-snug);
  cursor: pointer;
  transition:
    border-color var(--dur-fast) var(--ease-out),
    background-color var(--dur-fast) var(--ease-out);
}
.choice input {
  flex: none;
  width: var(--check);
  height: var(--check);
  margin: 0;
  accent-color: var(--accent-fg);
  cursor: pointer;
}
.choice input:focus-visible { outline-offset: var(--s-half); }
.choice:has(input:checked) {
  border-color: var(--accent-fg);
  box-shadow: inset 0 0 0 var(--bw) var(--accent-fg);
}
/* Light grounds: selected option gets the yellow tint (ink text stays 13:1+) */
:is(.band-light, .band-raised) .choice:has(input:checked) {
  background: var(--c-signal-tint);
  border-color: var(--c-ink);
  box-shadow: inset 0 0 0 var(--bw) var(--c-ink);
}
@media (hover: hover) {
  .choice:hover { border-color: var(--fg-muted); }
  .choice:has(input:checked):hover { border-color: var(--accent-fg); }
}

@media (min-width: 1024px) {
  .contact {
    min-height: calc(100vh - var(--header-h));
    min-height: calc(100svh - var(--header-h));
  }
  .contact-layout {
    grid-template-columns: minmax(0, 5fr) minmax(0, 7fr);
    column-gap: var(--s-12);
    align-items: start;
  }
  /* Narrow column: cap the display size so long words never overflow */
  .contact-intro .h-display { font-size: var(--fs-48); }
}
@media (min-width: 1280px) {
  .contact-intro .h-display { font-size: var(--fs-64); }
}


/* ==========================================================================
   3. Newsletter
   ========================================================================== */
.newsletter-layout {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: var(--s-12);
}
.newsletter-intro {
  display: grid;
  gap: var(--s-6);
  justify-items: start;
  align-content: start;
}
.newsletter-intro .eyebrow { margin-bottom: calc(-1 * var(--s-2)); }

.newsletter-card {
  display: grid;
  gap: var(--s-6);
  min-width: 0;
}
@media (min-width: 768px) {
  .newsletter-card { padding: var(--s-8); }
}

.newsletter-state {
  display: grid;
  gap: var(--s-3);
  justify-items: start;
}
.newsletter-state a {
  color: var(--link-fg);
  text-decoration-color: var(--link-line);
  text-decoration-thickness: var(--underline);
}

.consent-field {
  display: grid;
  gap: var(--s-1);
}

@media (min-width: 1024px) {
  .newsletter {
    min-height: calc(100vh - var(--header-h));
    min-height: calc(100svh - var(--header-h));
  }
  .newsletter-layout {
    grid-template-columns: minmax(0, 7fr) minmax(0, 5fr);
    column-gap: var(--s-16);
    align-items: start;
  }
}


/* ==========================================================================
   4. Legal
   ========================================================================== */
.legal-layout {
  display: grid;
  grid-template-columns: minmax(0, 1fr);
  gap: var(--s-12);
}

.legal-toc {
  display: grid;
  gap: var(--s-3);
  align-content: start;
  align-self: start;
}
.legal-toc-list {
  list-style: none;
  margin: 0;
  padding: 0;
  border-top: var(--bw) solid var(--line);
}
.legal-toc-list a {
  display: flex;
  align-items: center;
  gap: var(--s-3);
  min-height: var(--touch);
  padding-block: var(--s-2);
  border-bottom: var(--bw) solid var(--line);
  color: var(--fg);
  font-weight: var(--fw-medium);
  text-decoration: none;
}
.legal-toc-list a:focus-visible { outline-offset: calc(-1 * var(--focus-width)); }
@media (hover: hover) {
  .legal-toc-list a:hover span:last-child {
    text-decoration: underline;
    text-decoration-color: var(--link-line);
    text-decoration-thickness: var(--underline);
    text-underline-offset: var(--underline-offset);
  }
}
.legal-toc-num {
  flex: none;
  min-width: 3ch;
  font-family: var(--font-mono);
  font-size: var(--fs-12);
  font-weight: var(--fw-medium);
  letter-spacing: var(--ls-label);
  color: var(--accent-fg);
}

.legal-body {
  display: grid;
  gap: var(--s-12);
  min-width: 0;
}
.legal-section { max-width: var(--measure); }
.legal-section + .legal-section {
  padding-top: var(--s-12);
  border-top: var(--bw) solid var(--line);
}
.legal-section ul {
  margin-bottom: 0;
  padding-left: var(--s-6);
}
.legal-section li + li { margin-top: var(--s-4); }
.legal-section li::marker { color: var(--accent-fg); }

@media (min-width: 1024px) {
  .legal-layout {
    grid-template-columns: minmax(0, 3fr) minmax(0, 9fr);
    column-gap: var(--gutter);
  }
  .legal-toc {
    position: sticky;
    top: calc(var(--header-h) + var(--s-8));
  }
}


/* ==========================================================================
   5. 404
   ========================================================================== */
.not-found {
  display: flex;
  align-items: center;
  min-height: calc(100vh - var(--header-h));
  min-height: calc(100svh - var(--header-h));
  padding-block: var(--section-pad);
}
.not-found-inner {
  display: grid;
  gap: var(--s-6);
  justify-items: start;
}
.not-found-code {
  padding-bottom: var(--s-4);
  border-bottom: var(--bw) solid var(--line);
  font-family: var(--font-mono);
  font-size: var(--fs-48);
  font-weight: var(--fw-medium);
  line-height: 1;
  letter-spacing: var(--ls-label);
  font-variant-numeric: tabular-nums;
  color: var(--accent-fg);
}
.not-found-actions {
  display: flex;
  flex-wrap: wrap;
  gap: var(--s-3);
  margin-top: var(--s-2);
}
@media (min-width: 768px) {
  .not-found-code { font-size: var(--fs-64); }
}