.challenge-announcement { background: #fff1c8; color: var(--blue-deep); }
.home-page .challenge-announcement + .latest-section { padding-top: 36px; }
.challenge-announcement-inner { display: flex; align-items: center; justify-content: space-between; gap: 22px; padding-block: 17px; }
.challenge-announcement h2 { margin: 0; font-size: clamp(20px, 1.7vw, 24px); line-height: 1.25; font-weight: 600; letter-spacing: -.025em; }
.challenge-announcement p { margin: 5px 0 0; font-size: 14px; line-height: 1.5; color: var(--blue-deep); }
.challenge-announcement strong { display: inline-block; margin-left: 8px; font-weight: 700; }
.challenge-announcement a, .challenge-invitation a { display: inline-flex; align-items: center; gap: 16px; color: var(--blue-deep); font-size: 17px; line-height: 1.4; font-weight: 700; text-decoration: underline; text-underline-offset: 5px; }
.challenge-announcement a { flex-shrink: 0; font-size: 15px; }
.challenge-announcement svg, .challenge-invitation svg { width: 22px; height: 22px; fill: none; stroke: currentColor; stroke-width: 1.7; stroke-linecap: round; stroke-linejoin: round; flex-shrink: 0; }
.challenge-invitation { position: fixed; left: 24px; bottom: 24px; z-index: 70; width: min(370px, calc(100vw - 48px)); padding: 25px; border: 1px solid #cfdee8; background: white; box-shadow: 0 8px 32px rgba(29, 56, 76, .14); color: var(--blue-deep); }
.challenge-invitation[hidden] { display: none; }
.challenge-invitation h2 { max-width: 17ch; margin: 0 24px 0 0; font-size: 25px; font-weight: 600; line-height: 1.15; letter-spacing: -.025em; }
.challenge-invitation p { margin: 13px 0 17px; color: var(--copy); font-size: 16px; line-height: 1.5; }
.challenge-invitation-close { position: absolute; right: 7px; top: 7px; display: grid; place-items: center; width: 44px; height: 44px; border: 0; background: transparent; color: var(--blue-deep); cursor: pointer; }
.challenge-invitation-close:hover { background: #f0f5f8; }
.challenge-invitation :is(a, button):focus-visible, .challenge-announcement a:focus-visible { outline: 3px solid var(--blue); outline-offset: 4px; }
@media (max-width: 760px) {
  .home-page .challenge-announcement + .latest-section { padding-top: 28px; }
  .challenge-announcement-inner { display: block; padding-block: 16px; }
  .challenge-announcement a { margin-top: 10px; }
  .challenge-announcement strong { margin-left: 0; }
  .challenge-invitation { left: 12px; bottom: max(12px, env(safe-area-inset-bottom)); width: calc(100vw - 24px); padding: 22px; }
  .challenge-invitation h2 { font-size: 24px; }
}