/* ============================================================
   Tiancode — Website Layout (OpenAI Editorial Style)
   Loader, header minimalista, barra de anuncio editorial,
   grilla de metadatos técnicos y footer de alta fidelidad.
   ============================================================ */

/* ================= Loader ================= */
#loader {
  position: fixed;
  inset: 0;
  z-index: 200;
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  gap: 20px;
  overflow: hidden;
  background: var(--bg);
  transition: opacity 0.4s ease, transform 0.4s ease, visibility 0.4s ease;
}
#loader.is-hidden { opacity: 0; visibility: hidden; transform: scale(1.02); pointer-events: none; }

.loader-aurora { position: absolute; inset: 0; overflow: hidden; pointer-events: none; }
.loader-orb {
  position: absolute;
  width: 440px;
  height: 440px;
  border-radius: 50%;
  filter: blur(80px);
  will-change: transform;
}
.loader-orb--1 {
  top: -120px;
  left: -100px;
  background: radial-gradient(circle, var(--hero-glow-1), transparent 70%);
  animation: orb-drift-1 14s ease-in-out infinite alternate;
}
.loader-orb--2 {
  bottom: -140px;
  right: -120px;
  background: radial-gradient(circle, var(--hero-glow-2), transparent 70%);
  animation: orb-drift-2 18s ease-in-out infinite alternate;
}
@keyframes orb-drift-1 {
  from { transform: translate3d(0, 0, 0) scale(1); }
  to { transform: translate3d(80px, 60px, 0) scale(1.1); }
}
@keyframes orb-drift-2 {
  from { transform: translate3d(0, 0, 0) scale(1.1); }
  to { transform: translate3d(-70px, -50px, 0) scale(0.95); }
}

.loader-logo {
  position: relative;
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 14px;
  animation: logo-in 0.6s cubic-bezier(0.16, 1, 0.3, 1) 0.05s both;
}
@keyframes logo-in {
  from { opacity: 0; transform: scale(0.95) translateY(6px); }
  to { opacity: 1; transform: scale(1) translateY(0); }
}
.loader-mark { display: inline-block; width: 140px; height: auto; }
.loader-mark img { width: 100%; height: auto; object-fit: contain; }

.loader-mark .logo-theme-light,
.logo-mark .logo-theme-light { display: block; }
.loader-mark .logo-theme-dark,
.logo-mark .logo-theme-dark { display: none; }
[data-theme="light"] .loader-mark .logo-theme-light,
[data-theme="light"] .logo-mark .logo-theme-light { display: none; }
[data-theme="light"] .loader-mark .logo-theme-dark,
[data-theme="light"] .logo-mark .logo-theme-dark { display: block; }

.loader-word {
  font-size: 24px;
  font-weight: 700;
  letter-spacing: -0.03em;
  color: var(--text);
}

.loader-progress { display: flex; align-items: center; gap: 12px; }
.loader-track {
  width: 180px;
  height: 2px;
  border-radius: 999px;
  background: var(--border);
  overflow: hidden;
}
.loader-fill {
  position: relative;
  width: 0%;
  height: 100%;
  border-radius: inherit;
  background: var(--text);
  overflow: hidden;
}
.loader-pct {
  min-width: 36px;
  font-family: var(--font-mono);
  font-size: 11px;
  font-weight: 600;
  color: var(--text-3);
  text-align: right;
}
.loader-text {
  margin: -4px 0 0;
  font-family: var(--font-mono);
  font-size: 11px;
  font-weight: 500;
  letter-spacing: 0.08em;
  text-transform: uppercase;
  color: var(--text-3);
}

/* ================= Cabecera: una sola barra compacta =================
   Marca a la izquierda, píldora de secciones centrada (icono + texto,
   solo texto o solo icono según el ancho) y acciones a la derecha.
   Dentro del universo aparece el botón de volver y la píldora marca el
   panel activo; ninguna segunda barra. */
.site-header {
  position: sticky;
  top: 0;
  z-index: 80;
  background: var(--header-bg);
  -webkit-backdrop-filter: blur(20px) saturate(180%);
  backdrop-filter: blur(20px) saturate(180%);
  border-bottom: 1px solid var(--border);
  transition: background 0.25s ease, border-color 0.25s ease;
}
body:not(.universe-open):not(.page-open) .site-header {
  background: color-mix(in srgb, var(--bg) 42%, transparent);
  border-bottom-color: transparent;
}
/* La cabecera usa (casi) todo el ancho: la píldora queda centrada en la ventana y nunca
   pisa la marca ni las acciones. */
.site-header .container { width: min(1720px, 100% - clamp(32px, 4vw, 64px)); }
.header-inner {
  position: relative;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 14px;
  height: var(--header-h);
}

.header-left {
  display: flex;
  align-items: center;
  gap: 10px;
  min-width: 0;
}

.logo {
  display: inline-flex;
  align-items: center;
  gap: 9px;
  font-size: 16.5px;
  font-weight: 700;
  letter-spacing: -0.02em;
  color: var(--text);
  white-space: nowrap;
}
.logo-mark img { width: 26px; height: 18px; object-fit: contain; }

/* Botón de volver a la portada: solo dentro del universo */
.universe-back {
  display: none;
  flex-shrink: 0;
  align-items: center;
  justify-content: center;
  width: 34px;
  height: 34px;
  padding: 0;
  border: 1px solid var(--border);
  border-radius: 999px;
  background: var(--surface);
  color: var(--text-2);
  cursor: pointer;
  box-shadow: var(--shadow-sm);
  transition: color 0.18s ease, border-color 0.18s ease, transform 0.18s ease;
}
.universe-back svg { width: 15px; height: 15px; }
.universe-back:hover { color: var(--text); border-color: var(--border-strong); transform: translateX(-2px); }
body.universe-open .universe-back { display: inline-flex; animation: back-in 0.45s cubic-bezier(0.16, 1, 0.3, 1) both; }
@keyframes back-in {
  from { opacity: 0; transform: translateX(-8px); }
}

/* Píldora de secciones: centrada en la ventana, independiente de la marca y las acciones */
.main-nav {
  position: absolute;
  left: 50%;
  top: 50%;
  transform: translate(-50%, -50%);
  display: flex;
  align-items: center;
  gap: 2px;
  padding: 4px;
  border: 1px solid var(--border);
  border-radius: 999px;
  background: color-mix(in srgb, var(--surface) 74%, transparent);
  -webkit-backdrop-filter: blur(18px) saturate(160%);
  backdrop-filter: blur(18px) saturate(160%);
  box-shadow: var(--shadow-sm);
}
.main-nav > a,
.nav-dropdown-toggle {
  display: inline-flex;
  align-items: center;
  gap: 7px;
  padding: 5px 11px 5px 6px;
  border: 0;
  border-radius: 999px;
  background: transparent;
  color: var(--text-2);
  font-family: var(--font-sans);
  font-size: 12px;
  font-weight: 600;
  letter-spacing: -0.01em;
  line-height: 1;
  white-space: nowrap;
  cursor: pointer;
  transition: background 0.2s ease, color 0.2s ease;
}
.main-nav > a i,
.nav-dropdown-toggle i {
  display: grid;
  place-items: center;
  width: 22px;
  height: 22px;
  border-radius: 7px;
  background: var(--surface-3);
  color: var(--text-3);
  transition: background 0.2s ease, color 0.2s ease;
}
.main-nav > a i svg,
.nav-dropdown-toggle i svg { width: 12px; height: 12px; }
.main-nav > a:hover,
.nav-dropdown-toggle:hover,
.nav-dropdown.is-open .nav-dropdown-toggle { background: var(--surface-2); color: var(--text); }
.main-nav > a:hover i,
.nav-dropdown-toggle:hover i { color: var(--accent); }
.main-nav > a.is-active { background: var(--btn-primary-bg); color: var(--btn-primary-text); }
.main-nav > a.is-active i { background: color-mix(in srgb, var(--btn-primary-text) 14%, transparent); color: inherit; }
.nav-dropdown-toggle { padding-right: 9px; }
.nav-dropdown-toggle .chev { width: 11px; height: 11px; transition: transform 0.18s ease; }
.nav-dropdown.is-open .nav-dropdown-toggle .chev { transform: rotate(180deg); }

.header-actions {
  display: flex;
  align-items: center;
  justify-content: flex-end;
  gap: 8px;
}

/* Botón principal de descarga + menú de instalación (curl, PowerShell, npm, bun, brew) */
.header-cta-pill {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  padding: 7px 14px;
  border: 0;
  border-radius: var(--radius-pill);
  font-family: var(--font-sans);
  font-size: 12.5px;
  font-weight: 600;
  letter-spacing: -0.01em;
  line-height: 1;
  white-space: nowrap;
  background: var(--btn-primary-bg);
  color: var(--btn-primary-text);
  cursor: pointer;
  transition: background-color 0.18s ease, transform 0.18s ease;
}
.header-cta-pill:hover { background: var(--btn-primary-hover); }
.header-cta-pill svg { width: 14px; height: 14px; }

.install-menu { position: relative; display: inline-flex; align-items: stretch; }
.install-menu-short { display: none; }
@media (max-width: 1699px) {
  .install-menu-main > span:not(.install-menu-short) { display: none; }
  .install-menu-short { display: inline; }
}
.install-menu-main { border-radius: var(--radius-pill) 0 0 var(--radius-pill); padding-right: 11px; }
.install-menu-toggle {
  width: 28px;
  padding: 0;
  justify-content: center;
  margin-left: 1px;
  border-radius: 0 var(--radius-pill) var(--radius-pill) 0;
}
.install-menu-toggle .chev { width: 12px; height: 12px; transition: transform 0.18s ease; }
.install-menu.is-open .install-menu-toggle .chev { transform: rotate(180deg); }
.install-menu-panel {
  position: absolute;
  top: calc(100% + 10px);
  right: 0;
  z-index: 95;
  width: min(392px, calc(100vw - 32px));
  display: flex;
  flex-direction: column;
  gap: 1px;
  padding: 8px;
  border-radius: 16px;
  border: 1px solid var(--border-strong);
  background: var(--surface);
  box-shadow: var(--shadow-lg);
  opacity: 0;
  visibility: hidden;
  transform: translateY(6px);
  transition: opacity 0.18s ease, transform 0.18s ease, visibility 0.18s ease;
}
.install-menu-panel::before { content: ""; position: absolute; top: -10px; left: 0; right: 0; height: 10px; }
.install-menu.is-open .install-menu-panel { opacity: 1; visibility: visible; transform: none; }
.install-menu-label {
  display: block;
  padding: 7px 8px 4px;
  font-family: var(--font-mono);
  font-size: 10.5px;
  font-weight: 600;
  letter-spacing: 0.08em;
  text-transform: uppercase;
  color: var(--text-3);
}
.install-menu-sep { height: 1px; margin: 6px 4px 4px; background: var(--border); }
.install-menu-link {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 10px;
  padding: 8px 10px;
  border-radius: 10px;
  color: var(--text-3);
  font-size: 12.5px;
  transition: background-color 0.15s ease, color 0.15s ease;
}
.install-menu-link b { font-family: var(--font-mono); font-size: 12.5px; font-weight: 600; color: var(--text); }
.install-menu-link:hover { background: var(--btn-secondary-hover); color: var(--text-2); }
.install-menu-cmd {
  display: grid;
  grid-template-columns: 84px minmax(0, 1fr) 28px;
  align-items: center;
  gap: 8px;
  padding: 5px 6px 5px 10px;
  border-radius: 10px;
  transition: background-color 0.15s ease;
}
.install-menu-cmd:hover { background: var(--surface-2); }
.install-menu-os { font-size: 11px; font-weight: 600; color: var(--text-2); white-space: nowrap; }
.install-menu-cmd code {
  font-family: var(--font-mono);
  font-size: 11.5px;
  line-height: 1.4;
  color: var(--text);
  overflow: hidden;
  text-overflow: ellipsis;
  white-space: nowrap;
}
.install-menu-cmd .install-copy {
  position: static;
  transform: none;
  width: 28px;
  height: 28px;
  border: 1px solid var(--border);
  border-radius: 8px;
  background: var(--surface-3);
  color: var(--text-2);
  font-size: 13px;
  cursor: pointer;
  transition: background-color 0.15s ease, color 0.15s ease;
}
.install-menu-cmd .install-copy:hover { background: var(--btn-secondary-hover); color: var(--text); }
.install-menu-cmd .install-copy.is-copied { background: #10b981; border-color: #10b981; color: #fff; }
.install-menu-more {
  display: block;
  margin: 4px 2px 0;
  padding: 8px 10px;
  border-radius: 10px;
  text-align: center;
  font-size: 12.5px;
  font-weight: 600;
  color: var(--accent);
  transition: background-color 0.15s ease;
}
.install-menu-more:hover { background: var(--accent-soft); }

/* Botones circulares de acción (tema, lang, github) */
.icon-btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  width: 34px;
  height: 34px;
  border-radius: var(--radius-pill);
  border: 1px solid var(--border);
  background: transparent;
  color: var(--text-2);
  transition: all 0.15s ease;
}
.icon-btn:hover {
  color: var(--text);
  border-color: var(--border-strong);
  background: var(--btn-secondary-hover);
}
.icon-btn svg { width: 15px; height: 15px; }

.icon-sun { display: none; }
[data-theme="dark"] .icon-sun { display: block; }
[data-theme="dark"] .icon-moon { display: none; }

.lang-btn {
  min-width: 38px;
  font-family: var(--font-mono);
  font-size: 11px;
  font-weight: 600;
  letter-spacing: 0.04em;
}
.nav-toggle { display: none; }

/* Menú desplegable de recursos */
.nav-dropdown { position: relative; }
.nav-dropdown-menu {
  position: absolute;
  top: calc(100% + 12px);
  left: 50%;
  transform: translateX(-50%) translateY(6px);
  z-index: 90;
  min-width: 224px;
  display: flex;
  flex-direction: column;
  gap: 2px;
  padding: 6px;
  border-radius: var(--radius);
  border: 1px solid var(--border-strong);
  background: var(--surface);
  box-shadow: var(--shadow-lg);
  opacity: 0;
  visibility: hidden;
  transition: opacity 0.18s ease, transform 0.18s ease, visibility 0.18s ease;
}
.nav-dropdown-menu::before {
  content: "";
  position: absolute;
  top: -12px;
  left: 0;
  right: 0;
  height: 12px;
}
.nav-dropdown.is-open .nav-dropdown-menu,
.nav-dropdown:hover .nav-dropdown-menu {
  opacity: 1;
  visibility: visible;
  transform: translateX(-50%) translateY(0);
}
.nav-dropdown-menu a {
  padding: 8px 12px;
  border-radius: var(--radius-sm);
  font-size: 13px;
  font-weight: 500;
  color: var(--text-2);
  transition: background-color 0.15s ease, color 0.15s ease;
}
.nav-dropdown-menu a:hover {
  background: var(--btn-secondary-hover);
  color: var(--text);
}
.nav-dropdown-sep { height: 1px; margin: 4px 6px; background: var(--border); }

/* Anchos intermedios: la píldora pierde primero los iconos y después el texto */
@media (max-width: 1559px) {
  .main-nav > a i, .nav-dropdown-toggle i { display: none; }
  .main-nav > a { padding: 7px 9px; }
  .nav-dropdown-toggle { padding: 7px 7px 7px 9px; }
}
@media (max-width: 1239px) and (min-width: 901px) {
  .main-nav > a i, .nav-dropdown-toggle i { display: grid; width: 28px; height: 28px; background: transparent; }
  .main-nav > a i svg, .nav-dropdown-toggle i svg { width: 15px; height: 15px; }
  .main-nav > a span, .nav-dropdown-toggle span, .nav-dropdown-toggle .chev { display: none; }
  .main-nav > a, .nav-dropdown-toggle { padding: 3px; }
  .main-nav > a.is-active i { background: transparent; }
  .main-nav > a i, .nav-dropdown-toggle i { color: var(--text-2); }
}

/* ================= Cosmic Fixed Background & Hero Stage (OpenAI Astra Style) ================= */
.cosmic-canvas-container {
  position: fixed;
  inset: 0;
  width: 100vw;
  height: 100vh;
  pointer-events: none;
  z-index: -1;
  background: #000000;
  overflow: hidden;
}

#cosmic-galaxy-canvas {
  width: 100vw;
  height: 100vh;
  display: block;
}

.cosmic-hero-stage {
  position: relative;
  width: 100%;
  min-height: 85vh;
  background: transparent !important;
  display: flex !important;
  align-items: center !important;
  justify-content: center !important;
  overflow: hidden !important;
  user-select: none;
  border-bottom: 1px solid rgba(255, 255, 255, 0.08);
}

.cosmic-controls {
  position: absolute;
  bottom: clamp(20px, 3vh, 36px);
  right: clamp(24px, 4vw, 48px);
  z-index: 10;
}

.cosmic-replay-btn {
  width: 44px;
  height: 44px;
  border-radius: 9999px;
  background: rgba(255, 255, 255, 0.08);
  border: 1px solid rgba(255, 255, 255, 0.22);
  color: rgba(255, 255, 255, 0.85);
  display: inline-flex;
  align-items: center;
  justify-content: center;
  cursor: pointer;
  backdrop-filter: blur(12px);
  -webkit-backdrop-filter: blur(12px);
  transition: all 0.25s cubic-bezier(0.16, 1, 0.3, 1);
}

.cosmic-replay-btn:hover {
  background: rgba(255, 255, 255, 0.2);
  border-color: rgba(255, 255, 255, 0.5);
  color: #ffffff;
  transform: scale(1.1);
}

.cosmic-replay-btn svg {
  width: 19px;
  height: 19px;
  transition: transform 0.6s cubic-bezier(0.16, 1, 0.3, 1);
}

.cosmic-replay-btn.is-spinning svg {
  transform: rotate(360deg);
}

@media (max-width: 768px) {
  .cosmic-hero-stage { min-height: clamp(240px, 35vh, 360px); }
}

/* Fondo transparente para que el cosmos se vea en TODA la web */
body {
  background: transparent !important;
  background-color: transparent !important;
}

main, #home, .section {
  background: transparent !important;
}

.section-alt {
  background: rgba(255, 255, 255, 0.015) !important;
}

/* ================= Hero Editorial (OpenAI Announcement Style) ================= */
.hero-editorial {
  padding: 84px 0 64px;
}

.hero-editorial-head {
  max-width: 960px;
  margin: 0 auto;
  text-align: left;
}

.announcement-eyebrow {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  margin-bottom: 24px;
  font-family: var(--font-mono);
  font-size: 12px;
  font-weight: 600;
  letter-spacing: 0.1em;
  text-transform: uppercase;
  color: var(--text-3);
}
.eyebrow-pill {
  padding: 4px 10px;
  border-radius: var(--radius-pill);
  background: var(--surface-2);
  border: 1px solid var(--border);
  color: var(--text-2);
}
.eyebrow-dot {
  width: 6px;
  height: 6px;
  border-radius: 50%;
  background: #10b981;
}

.announcement-title {
  margin: 0 0 20px;
  font-size: clamp(2.4rem, 5.2vw, 4.4rem);
  font-weight: 650;
  letter-spacing: -0.038em;
  line-height: 1.06;
  color: var(--text);
}

.announcement-lead {
  margin: 0 0 32px;
  font-size: clamp(1.1rem, 1.8vw, 1.4rem);
  font-weight: 400;
  line-height: 1.55;
  color: var(--text-2);
  max-width: 880px;
}

.announcement-actions {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 14px;
  margin-bottom: 40px;
}

/* Barra de metadatos de lanzamiento estilo OpenAI (4 columnas) */
.announcement-meta {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 20px;
  padding: 24px 0;
  border-top: 1px solid var(--border);
  border-bottom: 1px solid var(--border);
  margin-bottom: 56px;
}
.meta-item {
  display: flex;
  flex-direction: column;
  gap: 4px;
}
.meta-label {
  font-family: var(--font-mono);
  font-size: 11px;
  font-weight: 600;
  text-transform: uppercase;
  letter-spacing: 0.08em;
  color: var(--text-3);
}
.meta-value {
  font-size: 14px;
  font-weight: 550;
  letter-spacing: -0.01em;
  color: var(--text);
}
.meta-value-sub {
  font-size: 12px;
  color: var(--text-3);
}

/* ================= Footer Minimalista (OpenAI Style) ================= */
.site-footer {
  border-top: 1px solid var(--border);
  background: var(--bg);
  padding: 72px 0 40px;
}
body:not(.page-open) .site-footer { display: none; }
body:not(.page-open) { overflow: hidden; }

.footer-inner {
  display: flex;
  flex-direction: column;
  gap: 48px;
}

.footer-top-row {
  display: flex;
  justify-content: space-between;
  align-items: flex-start;
  flex-wrap: wrap;
  gap: 24px;
}

.footer-brand-info {
  max-width: 360px;
}
.footer-brand-info .logo {
  font-size: 19px;
  margin-bottom: 12px;
}
.footer-tagline {
  margin: 0 0 16px;
  font-size: 14px;
  line-height: 1.6;
  color: var(--text-2);
}
.footer-status-badge {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  padding: 5px 12px;
  border-radius: var(--radius-pill);
  border: 1px solid var(--border);
  background: var(--surface-2);
  font-family: var(--font-mono);
  font-size: 11.5px;
  color: var(--text-2);
}
.footer-status-badge i {
  width: 7px;
  height: 7px;
  border-radius: 50%;
  background: #10b981;
  box-shadow: 0 0 0 2px rgba(16, 185, 129, 0.2);
}

.footer-cols-grid {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 36px;
  flex: 1;
  max-width: 680px;
}
.footer-col {
  display: flex;
  flex-direction: column;
  gap: 10px;
}
.footer-col-title {
  margin: 0 0 6px;
  font-family: var(--font-mono);
  font-size: 11px;
  font-weight: 600;
  letter-spacing: 0.1em;
  text-transform: uppercase;
  color: var(--text-3);
}
.footer-col a {
  font-size: 13.5px;
  color: var(--text-2);
  transition: color 0.15s ease;
}
.footer-col a:hover {
  color: var(--text);
}

.footer-bottom-bar {
  display: flex;
  justify-content: space-between;
  align-items: center;
  flex-wrap: wrap;
  gap: 16px;
  padding-top: 32px;
  border-top: 1px solid var(--border);
  font-size: 12.5px;
  color: var(--text-3);
}
.footer-bottom-bar a {
  color: var(--text-2);
  transition: color 0.15s ease;
}
.footer-bottom-bar a:hover {
  color: var(--text);
}

/* ================= Responsive Layout ================= */
@media (max-width: 960px) {
  .announcement-meta {
    grid-template-columns: repeat(2, 1fr);
    gap: 18px;
  }
  .footer-cols-grid {
    grid-template-columns: repeat(2, 1fr);
  }
}

@media (max-width: 900px) {
  .nav-toggle { display: inline-flex; }
  .main-nav {
    position: absolute;
    top: calc(100% + 8px);
    left: 16px;
    right: 16px;
    transform: none;
    flex-direction: column;
    align-items: stretch;
    gap: 2px;
    margin: 0;
    padding: 8px;
    border-radius: 18px;
    border: 1px solid var(--border-strong);
    background: var(--surface);
    box-shadow: var(--shadow-lg);
    -webkit-backdrop-filter: none;
    backdrop-filter: none;
    display: none;
  }
  .nav-open .main-nav { display: flex; }
  .main-nav > a, .nav-dropdown-toggle { width: 100%; padding: 10px 12px 10px 8px; border-radius: 12px; font-size: 14px; }
  .main-nav > a i, .nav-dropdown-toggle i { display: grid; width: 26px; height: 26px; }
  .main-nav > a i svg, .nav-dropdown-toggle i svg { width: 14px; height: 14px; }
  .nav-dropdown-toggle .chev { margin-left: auto; }
  .nav-dropdown-menu {
    position: static;
    transform: none;
    min-width: 0;
    padding: 0 0 4px 12px;
    border: 0;
    border-radius: 0;
    background: transparent;
    box-shadow: none;
    opacity: 1;
    visibility: visible;
    display: none;
  }
  .nav-dropdown.is-open .nav-dropdown-menu { display: flex; }
}

@media (max-width: 640px) {
  .header-inner { gap: 12px; }
  .header-actions { gap: 6px; }
  .header-actions .icon-btn { flex-shrink: 0; }
  .header-actions .install-menu,
  .header-actions > a.icon-btn { display: none; }
  .announcement-meta {
    grid-template-columns: 1fr;
    gap: 14px;
  }
  .footer-top-row {
    flex-direction: column;
  }
  .footer-cols-grid {
    grid-template-columns: 1fr 1fr;
    width: 100%;
  }
  .footer-bottom-bar {
    flex-direction: column;
    align-items: flex-start;
  }
}