.join-page {
  display: grid;
  grid-template-rows: auto 1fr auto;
  min-height: 100svh;
}

.join-main {
  display: grid;
  grid-template-columns: minmax(0, 0.9fr) minmax(320px, 1.1fr);
  gap: clamp(3rem, 6vw, 6rem);
  align-items: start;
  align-content: center;
  padding-block: 1.5rem;
}

.join-intro { position: sticky; top: 2rem; }
.join-intro h1 {
  max-width: 9ch;
  margin-top: 1rem;
  color: var(--ai-carbon);
  font-family: var(--font-ai-display);
  font-size: clamp(3rem, 5.5vw, 5.25rem);
  font-weight: 600;
  line-height: 0.96;
  letter-spacing: -0.055em;
}
.join-intro .aia-deck { margin-top: 1.25rem; }
.join-form-link { display: none; }
.join-benefits { margin-top: 1.25rem; border-top: 1px solid var(--ai-carbon); }
.join-benefits h2 {
  margin-block: 0.65rem 0.15rem;
  color: var(--ai-carbon-muted);
  font-family: var(--font-ai-mono);
  font-size: 0.7rem;
  font-weight: 500;
  letter-spacing: 0.08em;
  text-transform: uppercase;
}
.join-benefits ul { display: grid; grid-template-columns: repeat(3, minmax(0, 1fr)); margin: 0; padding: 0; border-bottom: 1px solid var(--ai-dust); list-style: none; }
.join-benefits li { display: grid; align-content: start; gap: 0.25rem; padding: 0.8rem 0.8rem 0.9rem 0; }
.join-benefits li + li { padding-left: 0.8rem; border-left: 1px solid var(--ai-dust); }
.join-benefits strong { color: var(--ai-carbon); font-family: var(--font-ai-display); font-size: 0.9rem; }
.join-benefits span { max-width: 44ch; color: var(--ai-carbon-muted); font-size: 0.75rem; }
.join-form { max-width: 680px; padding-top: 0.2rem; }
.join-form form { margin-top: 0; }
.join-form .field { margin-block: 0.95rem; }
.join-form .field label { display: block; margin-bottom: 0.35rem; }
.join-form .field-optional { color: var(--ai-carbon-muted); font-weight: 400; text-transform: lowercase; }
.join-form input:not([type="checkbox"]),
.join-form textarea {
  padding: 0.6rem 0.75rem;
  border: 0;
  border-bottom: 1px solid var(--ai-carbon);
  background: color-mix(in srgb, var(--ai-paper) 84%, var(--ai-dust));
}
.join-form input:not([type="checkbox"]):focus,
.join-form textarea:focus {
  border-bottom-color: var(--ai-signal-dark);
  background: var(--ai-paper-bright);
  box-shadow: inset 0 -2px 0 var(--ai-signal);
}
.join-form input::placeholder,
.join-form textarea::placeholder {
  color: var(--ai-carbon-muted);
  opacity: 0;
  transition: opacity 120ms ease;
}
.join-form input:focus::placeholder,
.join-form textarea:focus::placeholder { opacity: 0.78; }
.join-form textarea { min-height: 5.5rem; }
.join-form .consent { margin-block: 0.95rem; font-size: 0.75rem; }
.join-form .btn--primary {
  margin-top: 0.85rem;
  padding: 0.75rem 1rem;
  border-bottom-width: 3px;
  background: var(--ai-carbon);
  color: var(--ai-paper);
  cursor: pointer;
}
.join-form .btn--primary:hover {
  background: var(--ai-carbon);
  color: var(--ai-paper-bright);
  box-shadow: inset 0 -3px 0 var(--ai-signal);
}
.join-form .btn--primary:disabled { cursor: wait; opacity: 0.55; }
.join-form .form-status { min-height: 1.3em; margin-top: 0.8rem; }

@media (min-width: 901px) {
  .join-page .aia-header { padding-block: 0.8rem; }
  .join-page .aia-footer { padding-block: 0.8rem 1rem; }
}

@media (min-width: 901px) and (min-height: 900px) {
  .join-main { padding-block: 2.25rem; }
  .join-benefits { margin-top: 1.75rem; }
  .join-benefits li { padding-block: 1rem; }
  .join-form .field { margin-block: 1.15rem; }
  .join-form .consent { margin-block: 1.1rem; }
  .join-page .aia-footer { padding-block: 1.1rem 1.4rem; }
}

@media (max-width: 900px) {
  .join-page { display: block; min-height: 0; }
  .join-main { grid-template-columns: 1fr; padding-block: clamp(3.5rem, 7vw, 6rem); }
  .join-intro { position: static; }
  .join-intro h1 { max-width: 100%; }
  .join-form-link { display: inline-flex; margin-top: 1.25rem; font-family: var(--font-ai-mono); font-size: 0.72rem; text-transform: uppercase; }
  .join-form-link::after { content: " ↓"; color: var(--ai-signal); }
  .join-form { max-width: 720px; }
}

@media (max-width: 620px) {
  .join-main { gap: 2.5rem; padding-top: 3.5rem; }
  .join-intro h1 { font-size: clamp(2.5rem, 13vw, 4.3rem); }
  .join-intro .aia-deck { margin-top: 1.4rem; }
  .join-benefits { margin-top: 2.25rem; }
  .join-benefits ul { grid-template-columns: 1fr; }
  .join-benefits li { padding: 0.75rem 0; }
  .join-benefits li + li { border-top: 1px solid var(--ai-dust); border-left: 0; }
}