/* Shared public shell for platform routes and homepage instrument sections. */
:root {
  --platform-accent: var(--signal-text);
  --platform-cyan: var(--ice);
  --platform-amber: var(--amber);
  --platform-anomaly: #c7607b;
}

.platform-page {
  min-height: 100vh;
  color: var(--ink);
  background: var(--bg);
}

.platform-page .site-header.scrolled {
  top: 0;
  background: color-mix(in srgb, var(--bg) 94%, transparent);
  border-bottom-color: var(--line-strong);
}

.platform-page-main,
.article-page-main {
  position: relative;
  z-index: 1;
  margin-inline: auto;
  padding-top: calc(var(--platform-header-h, var(--header-h)) + 64px);
  padding-bottom: 96px;
}

.platform-page-main {
  width: min(1180px, calc(100% - 48px));
}

.platform-page-hero {
  position: relative;
  display: grid;
  grid-template-columns: minmax(0, 1fr) auto;
  align-items: end;
  gap: 32px;
  min-height: 250px;
  padding: 28px 0 48px;
  border-bottom: 1px solid var(--line-strong);
}

.platform-page-hero > div {
  min-width: 0;
}

.platform-page-hero h1 {
  max-width: 15ch;
  margin: 8px 0 14px;
  color: var(--ink);
  font-family: var(--font-title);
  font-size: 72px;
  font-weight: 600;
  line-height: 1.08;
  letter-spacing: 0;
  overflow-wrap: anywhere;
}

.platform-page-hero p:not(.platform-kicker) {
  max-width: 700px;
  color: var(--ink-dim);
  font-size: 16px;
  line-height: 1.8;
}

.platform-page-hero > strong {
  color: var(--platform-accent);
  font-family: var(--font-mono);
  font-size: 54px;
  font-weight: 500;
  line-height: 1;
  letter-spacing: 0;
}

.platform-list {
  margin-top: 48px;
}

.platform-kicker {
  display: flex;
  align-items: center;
  gap: 10px;
  margin: 0 0 8px;
  color: var(--ink-dim);
  font-family: var(--font-mono);
  font-size: 11px;
  font-weight: 500;
  line-height: 1.5;
  letter-spacing: 0;
}

.platform-kicker::before {
  width: 32px;
  border-top: 1px solid currentColor;
  content: "";
}

.platform-section {
  position: relative;
  min-height: 0;
  padding: 80px max(24px, calc((100vw - 1180px) / 2));
  border-top: 1px solid var(--line);
}

.platform-section .section-heading {
  margin-bottom: 40px;
}

.platform-section .section-heading > p,
.platform-section .section-heading > div > p:not(.platform-kicker) {
  max-width: 560px;
}

/* Shared empty state used by collection, signal, and missing-media fallbacks. */
.collection-empty {
  position: relative;
  display: grid;
  min-height: 220px;
  place-items: center;
  padding: 32px;
  color: var(--ink-dim);
  text-align: center;
  border: 1px dashed var(--line-strong);
}

.collection-empty::before,
.collection-empty::after {
  position: absolute;
  top: 50%;
  left: 50%;
  background: var(--line-strong);
  content: "";
}

.collection-empty::before {
  width: 48px;
  height: 1px;
  transform: translate(-50%, -50%);
}

.collection-empty::after {
  width: 1px;
  height: 48px;
  transform: translate(-50%, -50%);
}

.collection-empty > div {
  position: relative;
  z-index: 1;
  max-width: 420px;
  padding: 14px 18px;
  background: var(--bg);
}

.collection-empty b,
.collection-empty span {
  display: block;
}

.collection-empty b {
  margin-bottom: 7px;
  color: var(--ink);
  font-family: var(--font-mono);
  font-size: 11px;
  font-weight: 500;
  line-height: 1.5;
  letter-spacing: 0;
}

.collection-empty span {
  font-size: 14px;
  line-height: 1.7;
}

.platform-footer {
  position: relative;
  z-index: 1;
  display: grid;
  grid-template-columns: auto minmax(0, 1fr) auto auto;
  align-items: center;
  gap: 16px 28px;
  width: min(1180px, calc(100% - 48px));
  margin: 0 auto;
  padding: 28px 0 44px;
  color: var(--ink-dim);
  border-top: 1px solid var(--line-strong);
}

.platform-footer .brand,
.platform-footer a {
  color: var(--ink);
  text-decoration: none;
}

.platform-footer nav,
.platform-footer p {
  margin: 0;
}

.platform-footer p {
  font-family: var(--font-mono);
  font-size: var(--fs-micro);
  line-height: 1.6;
  letter-spacing: 0;
}

.platform-footer nav {
  font-size: 12px;
  white-space: nowrap;
}

.platform-footer button {
  min-height: 38px;
  padding: 0 14px;
  color: var(--signal-text);
  background: transparent;
  border: 1px solid var(--line-strong);
  font-family: var(--font-mono);
  font-size: 11px;
  font-weight: 500;
  line-height: 1;
  letter-spacing: 0;
  cursor: pointer;
}

.platform-footer button:hover,
.platform-footer button:focus-visible {
  border-color: var(--signal-text);
}

@media (max-width: 960px) {
  .platform-page-hero h1 {
    font-size: 56px;
  }

  .platform-section {
    padding-block: 72px;
  }

  .platform-footer {
    grid-template-columns: auto 1fr auto;
  }

  .platform-footer p {
    display: none;
  }
}

@media (max-width: 720px) {
  .platform-page {
    --platform-header-h: 108px;
  }

  .platform-page .site-header {
    display: grid;
    grid-template-columns: minmax(0, 1fr) auto;
    grid-template-rows: 56px 42px;
    align-items: center;
    width: 100%;
    height: var(--platform-header-h);
    padding: 0 16px 10px;
  }

  .platform-page .site-header .brand {
    min-width: 0;
  }

  .platform-page .site-header .header-actions {
    justify-self: end;
  }

  .platform-page .site-header .archive-back {
    font-size: var(--fs-micro);
  }

  .platform-page .site-header .desktop-nav {
    display: flex;
    grid-column: 1 / -1;
    grid-row: 2;
    width: 100%;
    gap: 0;
    overflow-x: auto;
    border-top: 1px solid var(--line);
    scrollbar-width: none;
  }

  .platform-page .site-header .desktop-nav::-webkit-scrollbar {
    display: none;
  }

  .platform-page .site-header .desktop-nav a {
    flex: 0 0 auto;
    min-height: 40px;
    padding: 0 14px;
    font-size: var(--fs-micro);
    line-height: 40px;
  }

  .platform-page-main,
  .article-page-main {
    padding-top: calc(var(--platform-header-h) + 36px);
    padding-bottom: 72px;
  }

  .platform-page-main {
    width: calc(100% - 32px);
  }

  .platform-page-hero {
    grid-template-columns: 1fr;
    gap: 18px;
    min-height: 0;
    padding: 12px 0 34px;
  }

  .platform-page-hero h1 {
    font-size: 40px;
    line-height: 1.14;
  }

  .platform-page-hero > strong {
    font-size: 34px;
  }

  .platform-list {
    margin-top: 32px;
  }

  .platform-section {
    padding: 64px 20px;
  }

  .platform-section .section-heading {
    margin-bottom: 28px;
  }

  .platform-footer {
    grid-template-columns: 1fr auto;
    width: calc(100% - 32px);
    padding: 24px 0 32px;
  }

  .platform-footer nav {
    grid-column: 1 / -1;
    grid-row: 2;
    white-space: normal;
  }
}

@media (max-width: 420px) {
  .platform-page .site-header .archive-back {
    max-width: 110px;
    overflow: hidden;
    text-overflow: ellipsis;
    white-space: nowrap;
  }

  .platform-footer {
    grid-template-columns: 1fr;
  }

  .platform-footer button {
    justify-self: start;
  }
}

@media print {
  .site-header,
  .platform-footer {
    display: none !important;
  }

  .platform-page-main,
  .article-page-main {
    width: 100%;
    padding: 0;
  }
}

/* PublicObservatoryShell -------------------------------------------------- */
.public-observatory-shell {
  --public-shell-header-h: 56px;
  --header-h: var(--public-shell-header-h);
  --platform-header-h: var(--public-shell-header-h);
  min-height: 100vh;
  color: var(--ink);
  background-color: var(--bg);
  isolation: isolate;
}

.public-observatory-shell .reveal,
.public-observatory-shell .reveal.is-visible {
  visibility: visible !important;
  opacity: 1 !important;
  transform: none !important;
  filter: none !important;
  clip-path: none !important;
}

.public-observatory-shell :where(section[id], article[id], [data-article-section-id], .article-block-placement[id]) {
  scroll-margin-top: calc(var(--public-shell-header-h) + 24px);
}

.public-observatory-shell::after {
  position: fixed;
  z-index: 0;
  inset: 0;
  pointer-events: none;
  content: "";
  opacity: .54;
  background-image:
    radial-gradient(circle at 12% 19%, color-mix(in srgb, var(--ice) 48%, transparent) 0 1px, transparent 1.6px),
    radial-gradient(circle at 78% 13%, color-mix(in srgb, var(--signal-text) 38%, transparent) 0 1px, transparent 1.5px),
    radial-gradient(circle at 58% 73%, color-mix(in srgb, var(--platform-anomaly) 32%, transparent) 0 1px, transparent 1.7px),
    linear-gradient(90deg, color-mix(in srgb, var(--ink) 3.5%, transparent) 1px, transparent 1px),
    linear-gradient(color-mix(in srgb, var(--ink) 3.5%, transparent) 1px, transparent 1px),
    radial-gradient(ellipse 72% 52% at 78% 4%, color-mix(in srgb, var(--ice) 6%, transparent), transparent 74%),
    radial-gradient(ellipse 52% 44% at 9% 82%, color-mix(in srgb, var(--signal-text) 5%, transparent), transparent 76%);
  background-position: 0 0, 0 0, 0 0, 0 0, 0 0, 0 0, 0 0;
  background-size: 173px 191px, 239px 211px, 293px 271px, 96px 100%, 100% 96px, 100% 100%, 100% 100%;
}

.public-observatory-shell[data-shell-motion="enabled"]::after {
  animation: public-shell-drift 42s linear infinite;
}

@keyframes public-shell-drift {
  to { background-position: 32px 18px, -24px 16px, 17px -28px, 0 0, 0 0, 0 0, 0 0; }
}

html[data-theme="light"] .public-observatory-shell::after {
  opacity: .7;
  background-image:
    radial-gradient(circle at 12% 19%, rgba(55, 104, 119, .18) 0 1px, transparent 1.6px),
    radial-gradient(circle at 78% 13%, rgba(73, 102, 51, .14) 0 1px, transparent 1.5px),
    radial-gradient(circle at 58% 73%, rgba(142, 67, 89, .11) 0 1px, transparent 1.7px),
    linear-gradient(90deg, rgba(29, 35, 42, .035) 1px, transparent 1px),
    linear-gradient(rgba(29, 35, 42, .035) 1px, transparent 1px),
    radial-gradient(ellipse 72% 52% at 78% 4%, rgba(255, 255, 255, .56), transparent 74%),
    radial-gradient(ellipse 52% 44% at 9% 82%, rgba(94, 126, 132, .07), transparent 76%);
}

.public-observatory-shell > main,
.public-observatory-shell > section,
.public-observatory-shell > article,
.public-observatory-shell > .platform-utility-dock,
.public-observatory-shell > .yukino-context-actions {
  position: relative;
  z-index: 1;
}

.public-observatory-shell.lost-signal-page {
  overflow-x: hidden;
  overflow-y: auto;
}

.public-shell-header {
  position: fixed !important;
  z-index: var(--z-header, 120) !important;
  /* 首屏让出 HUD 遥测带的高度，滚动后再由 html.obs-scrolled 收到顶部。
     这里不能写 top: 0 —— 那会抹掉整站页头的两段式层次。 */
  top: var(--chrome-top, 0px);
  right: 0;
  left: 0;
  display: flex !important;
  align-items: center;
  justify-content: space-between;
  gap: 20px;
  width: 100%;
  height: var(--public-shell-header-h) !important;
  margin: 0 !important;
  padding: 0 clamp(18px, 3vw, 40px) !important;
  color: var(--ink);
  background: color-mix(in srgb, var(--bg) 88%, transparent) !important;
  border-bottom: 1px solid var(--line-strong) !important;
  backdrop-filter: blur(16px);
  -webkit-backdrop-filter: blur(16px);
  transition: top .55s var(--ease-swift), background-color .4s, border-color .4s;
}

html.obs-scrolled .public-shell-header { top: 0; }

.public-shell-header .brand {
  flex: 0 0 auto;
  color: var(--ink);
  text-decoration: none;
}

.public-shell-header .desktop-nav {
  display: flex;
  align-items: center;
  justify-content: center;
  gap: clamp(16px, 2.4vw, 32px);
  min-width: 0;
  margin-inline: auto;
}

.public-shell-header .desktop-nav a {
  position: relative;
  flex: 0 0 auto;
  color: var(--ink-dim);
  font-family: var(--font-display, var(--font-sans));
  font-size: 13px;
  line-height: 1.2;
  letter-spacing: .18em;
  text-decoration: none;
  padding: 6px 0;
  transition: color .3s;
}

.public-shell-header .desktop-nav a::after {
  content: "";
  position: absolute;
  left: 0;
  bottom: 0;
  width: 100%;
  height: 1px;
  background: var(--signal-text);
  transform: scaleX(0);
  transform-origin: right;
  transition: transform .4s var(--ease-out, ease-out);
}

.public-shell-header .desktop-nav a:hover {
  color: var(--ink);
}

.public-shell-header .desktop-nav a:hover::after {
  transform: scaleX(1);
  transform-origin: left;
}

.public-shell-header .desktop-nav a.is-active,
.public-shell-header .desktop-nav a[aria-current] {
  color: var(--ink);
}

.public-shell-header .header-actions {
  flex: 0 0 auto;
  display: flex;
  align-items: center;
  gap: 4px;
}

.public-shell-header .lab-system-state,
.public-shell-header .custom-page-callsign,
.public-shell-header .lost-signal-status,
.public-shell-header > span:not(.brand-mark) {
  flex: 0 1 auto;
}

.public-shell-header .platform-mobile-nav-toggle {
  flex: 0 0 auto;
}

.platform-mobile-nav-toggle {
  display: none;
  width: 44px;
  height: 44px;
  padding: 0;
  place-items: center;
  color: var(--ink);
  background: transparent;
  border: 1px solid var(--line-strong);
  cursor: pointer;
}

.platform-mobile-nav-toggle .icon,
.platform-mobile-nav-close .icon {
  width: 18px;
  height: 18px;
}

.platform-mobile-nav {
  position: fixed;
  z-index: calc(var(--z-header, 120) + 20);
  inset: 0;
  display: grid;
  grid-template-rows: auto minmax(0, 1fr);
  gap: 28px;
  min-height: 100dvh;
  padding: calc(18px + env(safe-area-inset-top)) 18px calc(24px + env(safe-area-inset-bottom));
  color: var(--ink);
  background:
    linear-gradient(90deg, color-mix(in srgb, var(--ink) 4%, transparent) 1px, transparent 1px),
    linear-gradient(color-mix(in srgb, var(--ink) 4%, transparent) 1px, transparent 1px),
    color-mix(in srgb, var(--bg) 97%, var(--platform-cyan) 3%);
  background-size: 72px 100%, 100% 72px, auto;
  overflow-y: auto;
  overscroll-behavior: contain;
}

.platform-mobile-nav[hidden] {
  display: none !important;
}

.platform-mobile-nav > header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 20px;
  min-height: 52px;
  padding-bottom: 14px;
  border-bottom: 1px solid var(--line-strong);
}

.platform-mobile-nav > header div {
  display: grid;
  gap: 3px;
}

.platform-mobile-nav > header small {
  color: var(--platform-cyan);
  font: 500 var(--fs-micro)/1.4 var(--font-mono);
  letter-spacing: 0;
}

.platform-mobile-nav > header strong {
  font: 600 20px/1.25 var(--font-serif);
}

.platform-mobile-nav-close {
  display: grid;
  flex: 0 0 auto;
  width: 44px;
  height: 44px;
  padding: 0;
  place-items: center;
  color: var(--ink);
  background: transparent;
  border: 1px solid var(--line-strong);
  cursor: pointer;
}

.platform-mobile-nav nav {
  display: grid;
  align-content: start;
  gap: 0;
}

.platform-mobile-nav nav a {
  display: grid;
  grid-template-columns: minmax(0, 1fr) auto;
  align-items: baseline;
  gap: 16px;
  min-height: 60px;
  padding: 15px 4px;
  color: var(--ink);
  border-bottom: 1px solid var(--line);
  text-decoration: none;
}

.platform-mobile-nav nav a b {
  min-width: 0;
  font: 600 25px/1.2 var(--font-title);
  overflow-wrap: anywhere;
}

.platform-mobile-nav nav a span {
  color: var(--ink-faint);
  font: 500 var(--fs-micro)/1.3 var(--font-mono);
  letter-spacing: 0;
}

.platform-mobile-nav nav a.is-active,
.platform-mobile-nav nav a[aria-current],
.mobile-menu nav a.is-active,
.mobile-menu nav a[aria-current] {
  color: var(--signal-text);
}

.platform-mobile-nav nav a.is-active span,
.platform-mobile-nav nav a[aria-current] span {
  color: currentColor;
}

.platform-mobile-nav a.is-active,
.platform-mobile-nav a[aria-current] {
  color: var(--signal-text);
}

.public-shell-menu-open {
  overflow: hidden;
}

.public-observatory-shell[data-public-shell-navigation="hidden"] .public-shell-header .desktop-nav,
.public-observatory-shell[data-public-shell-navigation="hidden"] .platform-mobile-nav-toggle,
.public-observatory-shell[data-public-shell-navigation="hidden"] .platform-mobile-nav {
  display: none !important;
}

body > footer.public-shell-footer {
  position: relative;
  z-index: 2;
  display: grid !important;
  grid-template-columns: auto minmax(180px, 1fr) auto;
  align-items: center;
  gap: 16px 28px;
  width: min(1180px, calc(100% - 48px));
  min-height: 0;
  margin: 0 auto;
  padding: 32px 0 calc(42px + env(safe-area-inset-bottom));
  color: var(--ink-dim);
  background: transparent;
  border-top: 1px solid var(--line-strong);
}

/* 宽屏上 HIDDEN TRACK 固定在右下角（40px 高、距底 22px）；页脚末行留出这块，
   滚到底时按钮不会压住版权行。窄屏按钮会并入页脚，不需要让位。 */
@media (min-width: 561px) {
  body > footer.public-shell-footer { padding-bottom: calc(84px + env(safe-area-inset-bottom)); }
}

body > footer.public-shell-footer .brand {
  color: var(--ink);
  text-decoration: none;
}

body > footer.public-shell-footer > p {
  margin: 0;
  color: var(--ink-faint);
  font: 500 var(--fs-micro)/1.5 var(--font-mono);
  letter-spacing: 0;
}

body > footer.public-shell-footer nav,
body > footer.public-shell-footer .footer-links {
  display: flex;
  align-items: center;
  flex-wrap: wrap;
  justify-content: flex-end;
  gap: 0 8px;
  margin: 0;
}

body > footer.public-shell-footer nav a,
body > footer.public-shell-footer .footer-links a {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  min-width: 44px;
  min-height: 44px;
  color: var(--ink-dim);
  font: 500 11px/1.2 var(--font-sans);
  letter-spacing: 0;
  text-decoration: none;
}

body > footer.public-shell-footer nav a:hover,
body > footer.public-shell-footer nav a:focus-visible,
body > footer.public-shell-footer .footer-links a:hover,
body > footer.public-shell-footer .footer-links a:focus-visible {
  color: var(--ink);
}

/* 首页与子页的页脚 DOM 顺序不同（small 与 button 互换），
   所以这里显式定位到行列，避免同一份 CSS 在两种结构下排出两种版式。 */
body > footer.public-shell-footer > .brand { grid-area: 1 / 1; }
body > footer.public-shell-footer > p { grid-area: 1 / 2; }
body > footer.public-shell-footer > nav,
body > footer.public-shell-footer > .footer-links { grid-area: 1 / 3; }

body > footer.public-shell-footer #footer-build-number {
  grid-area: 2 / 1 / 3 / 3;
  justify-self: start;
  min-height: 38px;
  padding: 0 12px;
  color: var(--signal-text);
  background: color-mix(in srgb, var(--bg) 88%, transparent);
  border: 1px solid var(--line-strong);
  font: 500 var(--fs-micro)/1 var(--font-mono);
  letter-spacing: 0;
  cursor: pointer;
}

body > footer.public-shell-footer > small {
  grid-area: 2 / 3;
  justify-self: end;
  color: var(--ink-faint);
  font: 400 var(--fs-micro)/1.6 var(--font-mono);
  letter-spacing: 0;
}

.yukino-context-actions {
  display: flex;
  justify-content: center;
  gap: 18px;
  padding: 32px 20px;
}

.yukino-context-actions a,
.yukino-context-actions button {
  min-height: 44px;
  padding: 0 16px;
  color: inherit;
  background: transparent;
  border: 1px solid currentColor;
  text-decoration: none;
}

@media (max-width: 1040px) {
  .public-shell-header .desktop-nav { gap: 16px; }
  .public-shell-header .desktop-nav a { font-size: 12px; }
  .public-shell-header .lab-system-state,
  .public-shell-header .custom-page-callsign,
  .public-shell-header .lost-signal-status,
  .public-shell-header > span:not(.brand-mark) { display: none; }
}

@media (max-width: 760px) {
  .public-observatory-shell { --public-shell-header-h: 64px; }

  .public-shell-header,
  .platform-page .site-header.public-shell-header {
    display: flex !important;
    grid-template-columns: none;
    grid-template-rows: none;
    height: var(--public-shell-header-h) !important;
    padding: 0 14px !important;
  }

  .public-shell-header .desktop-nav,
  .platform-page .site-header.public-shell-header .desktop-nav { display: none !important; }
  .public-shell-header .platform-mobile-nav-toggle { display: grid; }
  /* 触控目标 44×44：按钮之间不再留缝，品牌字距收紧，给五个按钮腾出位置。 */
  .public-shell-header .header-actions { gap: 0; }
  .public-shell-header :is(.icon-button, .menu-button) { width: 44px; height: 44px; }
  .public-shell-header .menu-button span { left: 13px; right: 13px; }
  .public-shell-header .menu-button span:first-child { top: 18px; }
  .public-shell-header .menu-button span:last-child { top: 25px; }
  .public-shell-header .menu-button.is-open span { top: 21px; }
  .public-shell-header .brand { letter-spacing: .04em; }
  .public-shell-header .archive-back { max-width: 116px; overflow: hidden; text-overflow: ellipsis; white-space: nowrap; }

  .platform-page-main,
  .article-page-main { padding-top: calc(var(--public-shell-header-h) + 38px); }

  body > footer.public-shell-footer {
    grid-template-columns: minmax(0, 1fr);
    justify-items: start;
    width: calc(100% - 32px);
    gap: 18px;
    padding-top: 28px;
    text-align: left;
  }

  body > footer.public-shell-footer > .brand,
  body > footer.public-shell-footer > p,
  body > footer.public-shell-footer > nav,
  body > footer.public-shell-footer > .footer-links,
  body > footer.public-shell-footer > #footer-build-number,
  body > footer.public-shell-footer > small {
    grid-area: auto;
  }

  body > footer.public-shell-footer > nav,
  body > footer.public-shell-footer > .footer-links {
    width: 100%;
    justify-content: flex-start;
    flex-wrap: wrap;
    gap: 4px 6px;
  }

  body > footer.public-shell-footer > small {
    justify-self: start;
    max-width: none;
    margin: 0;
    padding: 0;
  }
  .lost-signal-page main { padding-top: calc(var(--public-shell-header-h) + 40px); }
}

@media (prefers-reduced-motion: reduce) {
  .public-observatory-shell::after { animation: none !important; }
  .public-shell-header { backdrop-filter: none; -webkit-backdrop-filter: none; }
  .platform-mobile-nav,
  .platform-mobile-nav * { scroll-behavior: auto !important; transition: none !important; animation: none !important; }
}

@media (max-width: 380px) {
  .public-shell-header .brand > span:last-child:not(.brand-mark) { display: none; }
}

@media print {
  .public-observatory-shell::after,
  .public-shell-header,
  .platform-mobile-nav,
  .platform-mobile-nav-toggle,
  body > footer.public-shell-footer { display: none !important; }

  .public-observatory-shell .reveal,
  .public-observatory-shell .reveal.is-visible { visibility: visible !important; opacity: 1 !important; transform: none !important; filter: none !important; }
}