/* Alpha-only layout. Shared AdviceForge tokens and components remain authoritative. */
.cos-alpha { --alpha-rule: 1px solid var(--outline); }
.cos-alpha [hidden] { display: none !important; }
.cos-alpha [id] { scroll-margin-top: 6rem; }
.cos-alpha a:focus-visible, .cos-alpha summary:focus-visible, .cos-alpha button:focus-visible { outline: 3px solid var(--secondary); outline-offset: 5px; }
.cos-alpha__hero.section--hero { padding: 2.5rem 0; }
.cos-alpha__hero-grid { display: grid; gap: 2rem; align-items: start; }
.cos-alpha__intro { min-width: 0; }
.cos-alpha .hero-title { font-size: clamp(2.5rem, 4.3vw, 3.6rem); max-width: 15ch; margin: 1rem 0 1.25rem; line-height: 1.06; }
.cos-alpha .hero-copy { font-size: 1.125rem; max-width: 38ch; }
.cos-alpha .button { letter-spacing: .07em; min-height: 2.85rem; padding: .8rem 1rem; text-align: center; }
.cos-alpha__download-action { margin-top: 1.5rem; }
.cos-alpha__primary-action > .button { width: 100%; }
.cos-alpha__download-hint { display: block; font-size: .875rem; color: var(--muted); margin-top: .5rem; }
.cos-alpha__status { color: var(--primary); border-left: 3px solid var(--secondary); padding: .35rem 0 .35rem 1rem; font-weight: 600; }
.cos-alpha__offer { color: var(--muted); font-size: .875rem; line-height: 1.7; margin: 1rem 0 .5rem; }
.cos-alpha__text-link { display: inline-flex; gap: .5rem; align-items: center; min-height: 44px; color: var(--primary); font-size: .875rem; text-decoration: underline; text-underline-offset: .25em; }
.cos-alpha__preview { margin: 0; min-width: 0; background: var(--surface-card); border: var(--alpha-rule); border-radius: var(--radius-lg); box-shadow: var(--shadow-card); overflow: hidden; }
.cos-alpha__preview a { display: block; }
.cos-alpha__preview img { display: block; width: 100%; height: auto; }
.cos-alpha__preview figcaption { color: var(--primary); font-size: .875rem; padding: .85rem 1.2rem; border-top: var(--alpha-rule); }
.cos-alpha__preview figcaption span { display: block; margin-top: .25rem; color: var(--muted); }
.cos-alpha h2 { font-size: 1.5rem; letter-spacing: -.04em; line-height: 1.2; margin: 0 0 .75rem; }
.cos-alpha h3 { font-size: 1.125rem; letter-spacing: -.025em; line-height: 1.25; color: var(--primary); margin: 1.25rem 0 .6rem; }
.cos-alpha .cos-alpha__participate { display: grid; gap: 1.5rem; padding-top: 1.75rem; padding-bottom: 1.75rem; border-top: var(--alpha-rule); border-bottom: var(--alpha-rule); }
.cos-alpha__participate p { color: var(--muted); max-width: 50ch; margin: 0; }
.cos-alpha__participate .cos-alpha__contact { margin-top: .75rem; font-size: .875rem; }
.cos-alpha__contact a { display: inline-flex; gap: .5rem; align-items: center; min-height: 2.75rem; color: var(--primary); text-decoration: underline; text-underline-offset: .2em; }
.cos-alpha .cos-alpha__help { padding-top: 2rem; padding-bottom: 2rem; }
.cos-alpha__help h2 { font-size: 1.125rem; margin-bottom: 1rem; }
.cos-alpha summary { cursor: pointer; min-height: 2.75rem; padding: .75rem 0; line-height: 1.5; font-weight: 600; }
.cos-alpha__details { border-bottom: var(--alpha-rule); }
.cos-alpha__help-content { max-width: 70ch; padding-bottom: .75rem; }
.cos-alpha__help-content p { margin: .4rem 0 1rem; color: var(--muted); }
.cos-alpha__prose { color: var(--muted); }
.cos-alpha__prose ul { padding-left: 1.2rem; }
.cos-alpha__prose li { padding-left: .2rem; margin: .7rem 0; }
.cos-alpha__recent { border-top: var(--alpha-rule); margin-top: 1rem; }
.cos-alpha__legal { display: flex; flex-wrap: wrap; gap: .5rem 1.5rem; margin: 1rem 0 0; font-size: .875rem; }
.cos-alpha__legal a { display: inline-flex; align-items: center; min-height: 2.75rem; text-decoration: underline; text-underline-offset: .2em; }
.cos-alpha__small { font-size: .875rem; color: var(--muted); margin-top: 1rem; }

/* Secondary packages stay in the welcome area, without a second download UI. */
.cos-alpha__other-downloads { font-size: .875rem; }
.cos-alpha__other-downloads > summary { width: fit-content; }
.cos-alpha__downloads { display: grid; gap: .75rem; padding-top: .75rem; }
.cos-alpha__download { min-width: 0; padding: 1rem; background: var(--surface-card); border: var(--alpha-rule); border-radius: var(--radius-md); }
.cos-alpha__platform { color: var(--muted); }
.cos-alpha__download h3 { margin: .25rem 0 .75rem; }
.cos-alpha__build-details { margin: 1rem 0; font-size: .875rem; }
.cos-alpha__build-details > div { display: flex; justify-content: space-between; gap: 1rem; margin: .5rem 0; }
.cos-alpha__build-details dt { color: var(--muted); }
.cos-alpha__build-details dd { margin: 0; text-align: right; }
.cos-alpha__download .button { width: 100%; }
.cos-alpha__signing-note { font-size: .875rem; color: var(--primary); margin: .75rem 0; }
.cos-alpha__checksum { margin-top: .65rem; color: var(--muted); }
.cos-alpha__checksum p { overflow-wrap: anywhere; margin: .5rem 0; }
.cos-alpha__checksum code { display: block; overflow-wrap: anywhere; font-size: .875rem; }
.cos-alpha__chooser { width: min(30rem, calc(100% - 2rem)); max-height: calc(100% - 2rem); padding: 1.5rem; color: var(--primary); background: var(--surface-card); border: var(--alpha-rule); border-radius: var(--radius-md); box-shadow: var(--shadow-card); }
.cos-alpha__chooser::backdrop { background: rgb(15 23 42 / 50%); }
.cos-alpha__chooser form { display: flex; justify-content: end; }
.cos-alpha__chooser form button { border: 0; background: transparent; cursor: pointer; }
.cos-alpha__chooser h2 { margin-top: .75rem; }
.cos-alpha__chooser-links { display: grid; gap: .75rem; margin: 1.5rem 0; }

/* The letter scrolls independently so dismissal is always available. */
html.cos-alpha-welcome-open,
html.cos-alpha-welcome-open body { overflow: hidden; }
.cos-alpha__welcome-link { border: 0; padding: 0; background: transparent; cursor: pointer; }
.cos-alpha__welcome {
  width: min(48rem, calc(100% - 1.5rem));
  max-width: none;
  max-height: calc(100dvh - 1.5rem);
  padding: 0;
  color: var(--primary);
  background: var(--surface-card);
  border: var(--alpha-rule);
  border-radius: var(--radius-lg);
  box-shadow: 0 24px 80px rgb(15 23 42 / 25%);
  overflow: hidden;
}
.cos-alpha__welcome[open] { display: flex; flex-direction: column; }
.cos-alpha__welcome::backdrop { background: rgb(15 23 42 / 60%); backdrop-filter: blur(5px); }
.cos-alpha__welcome-header,
.cos-alpha__welcome-footer { flex-shrink: 0; padding: 1.25rem; }
.cos-alpha__welcome-header { display: flex; align-items: flex-start; justify-content: space-between; gap: 1rem; border-bottom: var(--alpha-rule); }
.cos-alpha__welcome-header .eyebrow { margin: 0 0 .6rem; }
.cos-alpha__welcome-header h2 { margin: 0; font-size: clamp(1.65rem, 4vw, 2.25rem); line-height: 1.15; letter-spacing: -.04em; }
.cos-alpha__welcome-header h2:focus { outline: none; }
.cos-alpha__welcome-header form { flex-shrink: 0; }
.cos-alpha__welcome-close { display: grid; place-items: center; width: 2.75rem; height: 2.75rem; padding: 0; border: var(--alpha-rule); border-radius: 50%; background: transparent; color: var(--primary); font: inherit; font-size: 1.65rem; cursor: pointer; }
.cos-alpha__welcome-close:hover { background: var(--surface-low); }
.cos-alpha__welcome-body { min-height: 0; padding: 1.25rem; overflow-y: auto; overscroll-behavior: contain; overflow-wrap: anywhere; font-size: 1rem; line-height: 1.75; }
.cos-alpha__welcome-body p { margin: 0 0 1.25rem; }
.cos-alpha__welcome-body h3 { margin: 2rem 0 1rem; font-size: 1.4rem; }
.cos-alpha__welcome-body .cos-alpha__welcome-signature { margin-bottom: 0; font-size: 1.25rem; font-weight: 600; }
.cos-alpha__welcome-body:focus-visible { outline: 2px solid var(--secondary); outline-offset: -4px; }
.cos-alpha__welcome-footer { border-top: var(--alpha-rule); }
.cos-alpha__welcome-footer .button { width: 100%; gap: .75rem; letter-spacing: .02em; }

@media (min-width: 720px) {
  .cos-alpha__welcome { width: min(48rem, calc(100% - 3rem)); max-height: calc(100dvh - 3rem); }
  .cos-alpha__welcome-header,
  .cos-alpha__welcome-footer { padding: 1.5rem 2.25rem; }
  .cos-alpha__welcome-body { padding: 1.75rem 2.25rem; font-size: 1.0625rem; }
  .cos-alpha__welcome-footer { display: flex; justify-content: flex-end; }
  .cos-alpha__welcome-footer .button { width: auto; }
}

@media (min-width: 720px) {
  .cos-alpha__primary-action > .button { width: auto; }
  .cos-alpha .cos-alpha__participate { grid-template-columns: repeat(2, minmax(0, 1fr)); gap: 3rem; }
}
@media (min-width: 1024px) {
  .cos-alpha__hero.section--hero { padding: 3rem 0; }
  .cos-alpha__hero-grid { grid-template-columns: minmax(0, 2fr) minmax(0, 3fr); gap: 2rem; align-items: center; }
}
@media (min-width: 1200px) {
  .cos-alpha__hero-grid { gap: 3rem; }
}
@media (prefers-reduced-motion: reduce) {
  .cos-alpha .button { transition: none; }
  .cos-alpha .button:hover { transform: none; }
}