:root {
  /* Breakpoints: align with frontend/src/shared/viewport.js (WIDE_MIN_WIDTH_PX) */
  --viewport-wide-min: 1024px;
  --viewport-narrow-max: 1023px;
  color-scheme: light;
  --bg: #f0f1f4;
  --surface: #ffffff;
  --text: #1a1d21;
  --muted: #4d5763;
  /* common.empty on --surface; dimmer than --muted, ≥4.5:1 */
  --text-empty: color-mix(in srgb, var(--muted) 82%, var(--surface));
  --border: #c8cfd8;
  --brand: #012292;
  --accent: var(--brand);
  --accent-text: var(--brand);
  --accent-hover: #011a6e;
  --accent-hover-text: #011a6e;
  --error: #9f1239;
  --overlay: rgb(0 0 0 / 0.4);
  --shadow: 0 1px 3px rgb(0 0 0 / 0.08);
  --shadow-lg: 0 8px 24px rgb(0 0 0 / 0.15);
  --accent-muted: color-mix(in srgb, var(--brand) 8%, var(--surface));
  --accent-border: color-mix(in srgb, var(--brand) 22%, var(--surface));
  --header-h: 3rem;
  /* Content width: 900px, max 100% (SPEC/req-ui.md) */
  --max-w: 56.25rem;
  --radius: 0.5rem;
  /* Liquid Glass (SPEC/req-ui.md) */
  --glass-blur: 12px;
  --glass-blur-overlay: 10px;
  --glass-saturate: 1.14;
  --surface-glass: color-mix(in srgb, var(--surface) 74%, transparent);
  --nav-panel-glass: color-mix(in srgb, var(--surface) 66%, transparent);
  --nav-backdrop-glass: color-mix(in srgb, var(--text) 28%, transparent);
  --nav-backdrop-fallback: color-mix(in srgb, var(--text) 35%, transparent);
  --overlay-glass: rgb(0 0 0 / 0.30);
  --modal-glass: color-mix(in srgb, var(--surface) 85%, transparent);
  --scroll-btn-glass: color-mix(in srgb, var(--surface) 52%, transparent);
  --scroll-btn-glass-hover: color-mix(in srgb, var(--surface) 62%, transparent);
  --scroll-btn-text-shadow: 0 0.5px 0 color-mix(in srgb, var(--surface) 92%, transparent),
    0 1px 3px rgb(0 0 0 / 0.14);
  --tooltip-glass: color-mix(in srgb, var(--surface) 72%, transparent);
  --language-menu-glass: color-mix(in srgb, var(--surface) 64%, transparent);
  --toast-success-glass: color-mix(in srgb, #e7f3eb 66%, transparent);
  --toast-error-glass: color-mix(in srgb, #fde8e8 66%, transparent);
  --toast-warn-glass: color-mix(in srgb, #fef9e7 66%, transparent);
  --toast-success-fallback: #e7f3eb;
  --toast-error-fallback: #fde8e8;
  --toast-warn-fallback: #fef9e7;
  --glass-border: color-mix(in srgb, var(--border) 70%, var(--surface));
  --glass-text-shadow: 0 0.5px 0 color-mix(in srgb, var(--surface) 85%, transparent),
    0 1px 2px rgb(0 0 0 / 0.07);
  --nav-drawer-duration: 0.3s;
  --nav-drawer-ease: cubic-bezier(0.22, 1, 0.36, 1);
  --glass-ramp-duration: 0.28s;
  --glass-ramp-ease: cubic-bezier(0.22, 1, 0.36, 1);
}

@media (prefers-color-scheme: dark) {
  :root:not([data-theme="light"]) {
    color-scheme: dark;
    --bg: #0e1013;
    --surface: #171a1f;
    --text: #e8eaed;
    --muted: #a8b1bb;
    --text-empty: color-mix(in srgb, var(--muted) 72%, var(--surface));
    --border: #323a44;
    --accent-text: #7aa8ff;
    --accent-hover-text: #9abaff;
    --error: #f87171;
    --overlay: rgb(0 0 0 / 0.6);
    --overlay-glass: rgb(0 0 0 / 0.42);
    --modal-glass: color-mix(in srgb, var(--surface) 86%, transparent);
    --scroll-btn-glass: color-mix(in srgb, var(--surface) 54%, transparent);
    --scroll-btn-glass-hover: color-mix(in srgb, var(--surface) 63%, transparent);
    --scroll-btn-text-shadow: 0 0.5px 0 color-mix(in srgb, var(--surface) 78%, transparent),
      0 1px 4px rgb(0 0 0 / 0.48);
    --tooltip-glass: color-mix(in srgb, var(--surface) 76%, transparent);
    --language-menu-glass: color-mix(in srgb, var(--surface) 68%, transparent);
    --toast-success-glass: color-mix(in srgb, #1e2a22 72%, transparent);
    --toast-error-glass: color-mix(in srgb, #2a1e1e 72%, transparent);
    --toast-warn-glass: color-mix(in srgb, #2a261e 72%, transparent);
    --toast-success-fallback: #1e2a22;
    --toast-error-fallback: #2a1e1e;
    --toast-warn-fallback: #2a261e;
    --glass-text-shadow: 0 0.5px 0 color-mix(in srgb, var(--surface) 70%, transparent),
      0 1px 3px rgb(0 0 0 / 0.35);
    --shadow: 0 1px 3px rgb(0 0 0 / 0.35);
    --shadow-lg: 0 8px 24px rgb(0 0 0 / 0.45);
    --accent-muted: color-mix(in srgb, var(--brand) 14%, var(--surface));
    --accent-border: color-mix(in srgb, var(--accent-text) 28%, var(--surface));
  }
}

:root[data-theme="dark"] {
  color-scheme: dark;
  --bg: #0e1013;
  --surface: #171a1f;
  --text: #e8eaed;
  --muted: #a8b1bb;
  --text-empty: color-mix(in srgb, var(--muted) 72%, var(--surface));
  --border: #323a44;
  --accent-text: #7aa8ff;
  --accent-hover-text: #9abaff;
  --error: #f87171;
  --overlay: rgb(0 0 0 / 0.6);
  --overlay-glass: rgb(0 0 0 / 0.42);
  --modal-glass: color-mix(in srgb, var(--surface) 86%, transparent);
  --scroll-btn-glass: color-mix(in srgb, var(--surface) 54%, transparent);
  --scroll-btn-glass-hover: color-mix(in srgb, var(--surface) 63%, transparent);
  --scroll-btn-text-shadow: 0 0.5px 0 color-mix(in srgb, var(--surface) 78%, transparent),
    0 1px 4px rgb(0 0 0 / 0.48);
  --tooltip-glass: color-mix(in srgb, var(--surface) 76%, transparent);
  --language-menu-glass: color-mix(in srgb, var(--surface) 68%, transparent);
  --toast-success-glass: color-mix(in srgb, #1e2a22 72%, transparent);
  --toast-error-glass: color-mix(in srgb, #2a1e1e 72%, transparent);
  --toast-warn-glass: color-mix(in srgb, #2a261e 72%, transparent);
  --toast-success-fallback: #1e2a22;
  --toast-error-fallback: #2a1e1e;
  --toast-warn-fallback: #2a261e;
  --glass-text-shadow: 0 0.5px 0 color-mix(in srgb, var(--surface) 70%, transparent),
    0 1px 3px rgb(0 0 0 / 0.35);
  --shadow: 0 1px 3px rgb(0 0 0 / 0.35);
  --shadow-lg: 0 8px 24px rgb(0 0 0 / 0.45);
  --accent-muted: color-mix(in srgb, var(--brand) 14%, var(--surface));
  --accent-border: color-mix(in srgb, var(--accent-text) 28%, var(--surface));
}

:root[data-theme="light"] {
  color-scheme: light;
}

/* common.empty display values (view mode, not input placeholder). */
.field-empty {
  color: var(--text-empty);
}

*,
*::before,
*::after {
  box-sizing: border-box;
}

html {
  font-size: 16px;
  overflow-x: clip;
  scrollbar-gutter: stable;
  min-height: 100vh;
  min-height: 100dvh;
  background: var(--bg);
}

body {
  margin: 0;
  min-height: 100vh;
  min-height: 100dvh;
  display: flex;
  flex-direction: column;
  font-family: system-ui, -apple-system, "Segoe UI", Roboto, sans-serif;
  line-height: 1.5;
  color: var(--text);
  background: var(--bg);
}

body > main {
  flex: 1 0 auto;
  width: 100%;
  min-width: 0;
}

a {
  color: var(--accent-text);
  text-decoration: none;
}

a:hover {
  color: var(--accent-hover-text);
  text-decoration: underline;
}

/* Liquid Glass — decorative ::before layer only; layout/box model unchanged */
.site-header,
.site-footer {
  isolation: isolate;
  background: transparent;
}

.site-header::before,
.site-footer::before {
  content: "";
  position: absolute;
  inset: 0;
  z-index: -1;
  pointer-events: none;
  background: var(--surface-glass);
}

.modal::before,
.scroll-region__btn::before,
.saved-toast::before,
.text-clamp__tooltip::before,
.language-dropdown__menu::before {
  content: "";
  position: absolute;
  inset: 0;
  z-index: -1;
  pointer-events: none;
  border-radius: inherit;
}

.modal-overlay {
  --glass-blur-ramp: var(--glass-blur-overlay);
}

@supports ((backdrop-filter: blur(1px)) or (-webkit-backdrop-filter: blur(1px))) {
  .site-header::before,
  .site-footer::before,
  .modal::before,
  .scroll-region__btn::before,
  .saved-toast::before,
  .text-clamp__tooltip::before,
  .language-dropdown__menu::before {
    backdrop-filter: blur(var(--glass-blur)) saturate(var(--glass-saturate));
    -webkit-backdrop-filter: blur(var(--glass-blur)) saturate(var(--glass-saturate));
  }

  .modal-overlay::before,
  .site-header__nav-panel::before {
    backdrop-filter: blur(var(--glass-blur-overlay)) saturate(var(--glass-saturate));
    -webkit-backdrop-filter: blur(var(--glass-blur-overlay)) saturate(var(--glass-saturate));
  }
}

@supports not ((backdrop-filter: blur(1px)) or (-webkit-backdrop-filter: blur(1px))) {
  .site-header::before,
  .site-footer::before,
  .site-header__nav-panel::before,
  .modal::before,
  .scroll-region__btn::before,
  .saved-toast::before,
  .text-clamp__tooltip::before,
  .language-dropdown__menu::before {
    background: var(--surface);
  }

  .modal-overlay::before {
    background: var(--overlay);
  }

  .saved-toast::before {
    background: var(--toast-success-fallback);
  }

  .saved-toast.error-toast::before {
    background: var(--toast-error-fallback);
  }

  .saved-toast.warn-toast::before {
    background: var(--toast-warn-fallback);
  }

  .site-header__nav-backdrop::before {
    background: var(--nav-backdrop-fallback);
  }
}

@media (prefers-reduced-transparency: reduce) {
  .site-header::before,
  .site-footer::before,
  .site-header__nav-panel::before,
  .modal::before,
  .scroll-region__btn::before,
  .saved-toast::before,
  .text-clamp__tooltip::before,
  .language-dropdown__menu::before {
    backdrop-filter: none;
    -webkit-backdrop-filter: none;
    background: var(--surface);
  }

  .modal-overlay::before,
  .site-header__nav-backdrop::before {
    backdrop-filter: none;
    -webkit-backdrop-filter: none;
  }

  .modal-overlay::before {
    background: var(--overlay);
  }

  .saved-toast::before {
    background: var(--toast-success-fallback);
  }

  .saved-toast.error-toast::before {
    background: var(--toast-error-fallback);
  }

  .saved-toast.warn-toast::before {
    background: var(--toast-warn-fallback);
  }

  .scroll-region__btn:hover::before {
    background: color-mix(in srgb, var(--text) 6%, var(--surface));
  }

  .site-header__nav-backdrop::before {
    background: var(--nav-backdrop-fallback);
  }
}

@media (prefers-reduced-motion: no-preference) {
  .modal-overlay::before {
    animation: glass-backdrop-ramp-in var(--glass-ramp-duration) var(--glass-ramp-ease) both;
  }

  .modal {
    animation: glass-modal-in 0.26s cubic-bezier(0.22, 1, 0.36, 1);
  }

  .scroll-region__btn::before {
    transition: background 0.18s ease;
  }

  .scroll-region__btn:hover::before {
    background: var(--scroll-btn-glass-hover);
  }

  .saved-toast.is-visible {
    animation: glass-toast-in 0.24s ease;
  }

  .text-clamp__tooltip {
    animation: glass-tooltip-in 0.16s ease;
  }

  .language-dropdown__menu:not([hidden])::before {
    animation: glass-backdrop-ramp-in 0.22s ease both;
  }
}

@media (prefers-reduced-transparency: reduce) {
  @media (prefers-reduced-motion: no-preference) {
    .modal-overlay::before {
      animation: glass-backdrop-fade-in var(--glass-ramp-duration) ease both;
    }

    .language-dropdown__menu:not([hidden])::before {
      animation: glass-backdrop-fade-in 0.22s ease both;
    }
  }
}

@supports not ((backdrop-filter: blur(1px)) or (-webkit-backdrop-filter: blur(1px))) {
  @media (prefers-reduced-motion: no-preference) {
    .modal-overlay::before {
      animation: glass-backdrop-fade-in var(--glass-ramp-duration) ease both;
    }

    .language-dropdown__menu:not([hidden])::before {
      animation: glass-backdrop-fade-in 0.22s ease both;
    }
  }
}

@media (prefers-reduced-motion: reduce) {
  .modal-overlay::before,
  .modal,
  .saved-toast.is-visible {
    animation: none;
  }

  .site-header__nav-drawer,
  .site-header__nav-backdrop,
  .site-header__nav-backdrop::before,
  .site-header__nav-panel,
  .site-header__nav-panel::before,
  .site-header__nav-panel .site-nav__link {
    transition: none;
  }

  .site-header__nav-drawer.is-open .site-nav__link {
    opacity: 1;
    transform: none;
  }

  .site-header__nav-drawer.is-open .site-header__nav-backdrop::before {
    animation: none;
    opacity: 1;
    backdrop-filter: blur(var(--glass-blur-overlay)) saturate(var(--glass-saturate));
    -webkit-backdrop-filter: blur(var(--glass-blur-overlay)) saturate(var(--glass-saturate));
  }

  .scroll-region__btn::before {
    transition: none;
  }

  .text-clamp__tooltip,
  .language-dropdown__menu::before {
    animation: none;
  }
}

@keyframes glass-backdrop-ramp-in {
  from {
    opacity: 0;
    backdrop-filter: blur(0) saturate(var(--glass-saturate));
    -webkit-backdrop-filter: blur(0) saturate(var(--glass-saturate));
  }

  to {
    opacity: 1;
    backdrop-filter: blur(var(--glass-blur-ramp, var(--glass-blur))) saturate(var(--glass-saturate));
    -webkit-backdrop-filter: blur(var(--glass-blur-ramp, var(--glass-blur))) saturate(var(--glass-saturate));
  }
}

@keyframes glass-backdrop-fade-in {
  from {
    opacity: 0;
  }

  to {
    opacity: 1;
  }
}

@keyframes glass-modal-in {
  from {
    opacity: 0;
    transform: translateY(0.5rem) scale(0.985);
  }

  to {
    opacity: 1;
    transform: translateY(0) scale(1);
  }
}

@keyframes glass-toast-in {
  from {
    opacity: 0;
    transform: translateY(0.65rem) scale(0.98);
  }

  to {
    opacity: 1;
    transform: translateY(0) scale(1);
  }
}

@keyframes glass-tooltip-in {
  from {
    opacity: 0;
  }

  to {
    opacity: 1;
  }
}

.modal::before {
  background: var(--modal-glass);
}

.scroll-region__btn::before {
  background: var(--scroll-btn-glass);
}

.saved-toast::before {
  background: var(--toast-success-glass);
}

.saved-toast.error-toast::before {
  background: var(--toast-error-glass);
}

.saved-toast.warn-toast::before {
  background: var(--toast-warn-glass);
}

.text-clamp__tooltip::before {
  background: var(--tooltip-glass);
}

.language-dropdown__menu::before {
  background: var(--language-menu-glass);
}

.site-header {
  position: sticky;
  top: 0;
  z-index: 10;
  flex-shrink: 0;
  height: var(--header-h);
  min-height: var(--header-h);
  max-height: var(--header-h);
  overflow: visible;
  border-bottom: 1px solid var(--border);
  box-shadow: var(--shadow);
}

.site-header__inner {
  position: relative;
  max-width: var(--max-w);
  margin: 0 auto;
  padding: 0 1rem;
  height: 100%;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 0.75rem;
}

.site-header__cluster {
  display: flex;
  align-items: center;
  min-width: 0;
}

.site-header__cluster--start {
  flex: 1 1 auto;
  gap: 1rem;
}

.site-header__cluster--end {
  flex: 0 0 auto;
  justify-content: flex-end;
}

.site-header__menu-nav {
  position: relative;
  display: flex;
  align-items: center;
  gap: 0.5rem;
}

.site-header__menu-btn {
  display: none;
  flex-shrink: 0;
  align-items: center;
  justify-content: center;
  width: 2.25rem;
  height: 2.25rem;
  padding: 0;
  border: none;
  border-radius: var(--radius);
  color: var(--muted);
  background: transparent;
  cursor: pointer;
}

.site-header__menu-btn:hover {
  color: var(--text);
  background: var(--bg);
}

.site-header__menu-btn:focus-visible {
  outline: 2px solid var(--accent-text);
  outline-offset: 2px;
}

.site-header__menu-btn img {
  display: block;
  width: 1.25rem;
  height: 1.25rem;
}

.site-header__nav-drawer {
  display: block;
}

.site-header__nav-backdrop,
.site-header__nav-close {
  display: none;
}

.site-header__nav-panel {
  display: block;
}

.site-header__nav-panel .site-header__brand {
  display: none;
}

.site-header__brand {
  display: inline-flex;
  align-items: center;
  gap: 0.375rem;
  position: static;
  transform: none;
  flex-shrink: 0;
  max-width: none;
  overflow: visible;
  white-space: nowrap;
  font-weight: 600;
  color: var(--text);
  text-decoration: none;
}

.site-header__brand-logo {
  flex-shrink: 0;
  display: block;
}

.site-header__brand:hover {
  text-decoration: none;
  color: var(--accent-text);
}

.site-nav {
  display: flex;
  gap: 0.25rem;
}

.site-nav__link {
  padding: 0.375rem 0.75rem;
  border-radius: var(--radius);
  color: var(--muted);
  font-weight: 500;
  text-decoration: none;
}

.site-nav__link:hover {
  color: var(--text);
  background: var(--bg);
  text-decoration: none;
}

.site-nav__link.is-active {
  color: var(--accent-text);
  background: var(--bg);
}

.site-header__actions {
  display: flex;
  align-items: center;
  gap: 0.25rem;
}

.language-dropdown {
  position: relative;
}

.language-dropdown__trigger {
  display: flex;
  align-items: center;
  gap: 0.375rem;
  white-space: nowrap;
  height: 2.25rem;
  padding: 0 0.625rem;
  border: none;
  border-radius: var(--radius);
  color: var(--muted);
  font: inherit;
  font-size: 0.875rem;
  font-weight: 500;
  background: transparent;
  cursor: pointer;
}

.language-dropdown__trigger:hover {
  color: var(--text);
  background: var(--bg);
}

.language-dropdown__trigger:focus-visible {
  outline: 2px solid var(--accent-text);
  outline-offset: 2px;
}

.language-dropdown__trigger img {
  display: block;
  width: 1.25rem;
  height: 1.25rem;
  flex-shrink: 0;
}

.language-dropdown__menu {
  position: absolute;
  top: calc(100% + 0.25rem);
  right: 0;
  z-index: 50;
  min-width: 10rem;
  margin: 0;
  padding: 0.25rem 0;
  list-style: none;
  isolation: isolate;
  background: transparent;
  border: 1px solid var(--glass-border);
  border-radius: var(--radius);
  box-shadow: var(--shadow-lg);
}

.language-dropdown__option {
  display: block;
  width: 100%;
  padding: 0.5rem 0.75rem;
  border: none;
  background: transparent;
  font: inherit;
  font-size: 0.875rem;
  text-align: left;
  color: var(--text);
  text-shadow: var(--glass-text-shadow);
  cursor: pointer;
}

.language-dropdown__option:hover,
.language-dropdown__option:focus-visible {
  background: color-mix(in srgb, var(--bg) 78%, transparent);
  outline: none;
}

.language-dropdown__option.is-active {
  font-weight: 600;
  color: var(--accent-text);
}

.theme-toggle {
  display: flex;
  align-items: center;
  gap: 0.375rem;
  white-space: nowrap;
  min-height: 2.25rem;
  padding: 0 0.625rem;
  border: none;
  border-radius: var(--radius);
  color: var(--muted);
  font: inherit;
  font-size: 0.875rem;
  font-weight: 500;
  background: transparent;
  cursor: pointer;
}

.theme-toggle:hover {
  color: var(--text);
  background: var(--bg);
}

.theme-toggle:focus-visible {
  outline: 2px solid var(--accent-text);
  outline-offset: 2px;
}

.theme-toggle img {
  display: block;
  width: 1.25rem;
  height: 1.25rem;
  flex-shrink: 0;
}

.theme-toggle__label {
  flex-shrink: 0;
}

/* narrow viewport: width < --viewport-wide-min; see frontend/src/shared/viewport.js */
@media (max-width: 1023px) {
  .site-header__menu-btn {
    display: inline-flex;
  }

  .site-header__cluster--start {
    flex: 0 0 auto;
  }

  .site-header__brand {
    position: absolute;
    left: 50%;
    top: 50%;
    z-index: 1;
    transform: translate(-50%, -50%);
    max-width: min(50%, 12rem);
  }

  .site-header__brand-label[data-text-clamp] {
    display: block;
    min-width: 0;
    overflow: hidden;
    text-overflow: ellipsis;
    white-space: nowrap;
  }

  .site-header__nav-drawer {
    position: fixed;
    inset: 0;
    z-index: 200;
    visibility: hidden;
    pointer-events: none;
    transition: visibility 0s linear var(--nav-drawer-duration);
  }

  .site-header__nav-drawer.is-open {
    visibility: visible;
    pointer-events: auto;
    transition: visibility 0s;
  }

  .site-header__nav-backdrop {
    --glass-blur-ramp: var(--glass-blur-overlay);
    display: block;
    position: absolute;
    inset: 0;
    isolation: isolate;
    background: transparent;
    opacity: 0;
    transition: opacity var(--nav-drawer-duration) var(--nav-drawer-ease);
  }

  .site-header__nav-backdrop::before {
    content: "";
    position: absolute;
    inset: 0;
    z-index: -1;
    pointer-events: none;
    background: var(--nav-backdrop-glass);
  }

  .site-header__nav-drawer.is-open .site-header__nav-backdrop {
    opacity: 1;
    transition: none;
  }

  .site-header__nav-panel {
    display: flex;
    flex-direction: column;
    position: absolute;
    top: 0;
    left: 0;
    bottom: 0;
    width: min(17.5rem, 88vw);
    min-width: 0;
    padding: 0;
    isolation: isolate;
    background: transparent;
    border: none;
    border-right: 1px solid var(--glass-border);
    border-radius: 0;
    box-shadow: var(--shadow-lg);
    transform: translate3d(-100%, 0, 0);
    transition: transform var(--nav-drawer-duration) var(--nav-drawer-ease);
  }

  .site-header__nav-panel::before {
    content: "";
    position: absolute;
    inset: 0;
    z-index: -1;
    pointer-events: none;
    background: var(--nav-panel-glass);
  }

  .site-header__nav-panel-head {
    display: flex;
    align-items: center;
    flex-shrink: 0;
    padding: 0.75rem 0.75rem 0.25rem;
  }

  .site-header__nav-panel-foot {
    margin-top: auto;
    flex-shrink: 0;
    padding: 0.5rem 0.75rem 0.75rem;
  }

  .site-header__nav-panel .site-header__brand {
    display: inline-flex;
    position: static;
    left: auto;
    top: auto;
    transform: none;
    min-width: 0;
    max-width: none;
    text-shadow: var(--glass-text-shadow);
  }

  .site-header__nav-panel .site-header__brand-label[data-text-clamp] {
    display: block;
    min-width: 0;
    overflow: hidden;
    text-overflow: ellipsis;
    white-space: nowrap;
  }

  .site-header__nav-panel .site-nav__link,
  .site-header__nav-panel .site-header__nav-close,
  .site-header__nav-panel .site-header__brand {
    text-shadow: var(--glass-text-shadow);
  }

  .site-header__nav-drawer.is-open .site-header__nav-panel {
    transform: translate3d(0, 0, 0);
    will-change: transform;
  }

  @supports ((backdrop-filter: blur(1px)) or (-webkit-backdrop-filter: blur(1px))) {
    .site-header__nav-backdrop::before,
    .site-header__nav-panel::before {
      backdrop-filter: blur(0) saturate(var(--glass-saturate));
      -webkit-backdrop-filter: blur(0) saturate(var(--glass-saturate));
      transition:
        backdrop-filter var(--nav-drawer-duration) var(--nav-drawer-ease),
        -webkit-backdrop-filter var(--nav-drawer-duration) var(--nav-drawer-ease);
    }

    .site-header__nav-drawer.is-open .site-header__nav-panel::before {
      backdrop-filter: blur(var(--glass-blur-overlay)) saturate(var(--glass-saturate));
      -webkit-backdrop-filter: blur(var(--glass-blur-overlay)) saturate(var(--glass-saturate));
    }
  }

  @media (prefers-reduced-motion: no-preference) {
    @supports ((backdrop-filter: blur(1px)) or (-webkit-backdrop-filter: blur(1px))) {
      .site-header__nav-drawer.is-open .site-header__nav-backdrop::before {
        animation: glass-backdrop-ramp-in var(--glass-ramp-duration) var(--glass-ramp-ease) both;
        transition: none;
      }
    }
  }

  @media (prefers-reduced-transparency: reduce) {
    @media (prefers-reduced-motion: no-preference) {
      @supports ((backdrop-filter: blur(1px)) or (-webkit-backdrop-filter: blur(1px))) {
        .site-header__nav-drawer.is-open .site-header__nav-backdrop::before {
          animation: glass-backdrop-fade-in var(--glass-ramp-duration) ease both;
        }
      }
    }
  }

  @supports not ((backdrop-filter: blur(1px)) or (-webkit-backdrop-filter: blur(1px))) {
    @media (prefers-reduced-motion: no-preference) {
      .site-header__nav-drawer.is-open .site-header__nav-backdrop::before {
        animation: glass-backdrop-fade-in var(--glass-ramp-duration) ease both;
      }
    }
  }

  .site-header__nav-panel .site-nav__link {
    opacity: 0;
    transform: translate3d(-0.375rem, 0, 0);
    transition:
      opacity 0.2s var(--nav-drawer-ease),
      transform 0.2s var(--nav-drawer-ease);
  }

  .site-header__nav-drawer.is-open .site-nav__link {
    opacity: 1;
    transform: translate3d(0, 0, 0);
  }

  .site-header__nav-drawer.is-open .site-nav__link:nth-child(1) {
    transition-delay: 0.05s;
  }

  .site-header__nav-drawer.is-open .site-nav__link:nth-child(2) {
    transition-delay: 0.09s;
  }

  .site-header__nav-close {
    display: flex;
    align-items: center;
    justify-content: flex-end;
    width: 100%;
    min-height: 3rem;
    margin: 0;
    padding: 0 0.75rem;
    border: none;
    border-radius: var(--radius);
    color: var(--muted);
    background: transparent;
    cursor: pointer;
  }

  .site-header__nav-close:hover {
    color: var(--text);
    background: var(--bg);
  }

  .site-header__nav-close:focus-visible {
    outline: 2px solid var(--accent-text);
    outline-offset: 2px;
  }

  .site-header__nav-close img {
    display: block;
    width: 1.25rem;
    height: 1.25rem;
  }

  .site-nav {
    flex-direction: column;
    gap: 0.125rem;
    padding: 0.25rem 0.5rem 1rem;
  }

  .language-dropdown__label,
  .theme-toggle__label {
    position: absolute;
    width: 1px;
    height: 1px;
    padding: 0;
    margin: -1px;
    overflow: hidden;
    clip: rect(0, 0, 0, 0);
    white-space: nowrap;
    border: 0;
  }

  .language-dropdown__trigger,
  .theme-toggle {
    padding: 0 0.5rem;
  }
}

@media (prefers-color-scheme: dark) {
  :root:not([data-theme="light"]) .language-dropdown__trigger img,
  :root[data-theme="dark"] .language-dropdown__trigger img,
  :root:not([data-theme="light"]) .theme-toggle img,
  :root[data-theme="dark"] .theme-toggle img,
  :root:not([data-theme="light"]) .site-header__menu-btn img,
  :root[data-theme="dark"] .site-header__menu-btn img,
  :root:not([data-theme="light"]) .site-header__nav-close img,
  :root[data-theme="dark"] .site-header__nav-close img {
    filter: invert(1);
  }
}

html.site-nav-drawer-open {
  overflow: hidden;
}

.site-footer {
  position: relative;
  flex-shrink: 0;
  border-top: 1px solid var(--border);
}

.site-footer__inner {
  max-width: var(--max-w);
  margin: 0 auto;
  padding: 1rem;
  display: flex;
  flex-direction: row;
  flex-wrap: nowrap;
  align-items: center;
  justify-content: center;
  gap: 0.5rem 1.5rem;
  font-size: 0.875rem;
  color: var(--muted);
}

.site-footer__copy {
  margin: 0;
}

.site-footer__links {
  display: flex;
  flex-wrap: nowrap;
  align-items: center;
  justify-content: center;
  gap: 0.5rem 1.25rem;
}

.site-footer a {
  color: inherit;
  text-decoration: underline;
}

.site-footer a:hover {
  color: var(--text);
  text-decoration: underline;
}

/* narrow viewport: width < 1024px; see frontend/src/shared/viewport.js */
@media (max-width: 1023px) {
  .site-footer__inner {
    flex-direction: column;
    flex-wrap: nowrap;
    text-align: center;
  }

  .site-footer__links {
    order: 1;
    flex-wrap: nowrap;
    justify-content: center;
    width: 100%;
  }

  .site-footer__copy {
    order: 2;
    width: 100%;
  }
}

.page {
  max-width: var(--max-w);
  margin: 0 auto;
  padding: 1.5rem 1rem 2rem;
  width: 100%;
  min-width: 0;
  box-sizing: border-box;
}

.page__title {
  margin: 0 0 0.5rem;
  font-size: 1.5rem;
  font-weight: 600;
  text-align: center;
}

.page__hint {
  margin: 0;
  color: var(--muted);
  font-size: 0.9375rem;
}

.btn {
  display: inline-flex;
  align-items: center;
  gap: 0.375rem;
  padding: 0.375rem 0.875rem;
  font-size: 0.875rem;
  font-family: inherit;
  border-radius: var(--radius);
  border: 1px solid var(--border);
  background: var(--surface);
  cursor: pointer;
}

.btn:hover {
  background: var(--bg);
}

.btn--primary {
  color: #fff;
  background: var(--accent);
  border-color: var(--accent);
}

.btn--primary:hover {
  background: var(--accent-hover);
  border-color: var(--accent-hover);
}

.btn__hint {
  font-size: 0.75rem;
  font-weight: 400;
  color: var(--muted);
}

.segmented {
  display: flex;
  width: 100%;
  max-width: 100%;
  min-width: 0;
}

.segmented__btn {
  position: relative;
  flex: 1 1 0;
  min-width: 0;
  margin-left: -1px;
  padding: 0.5rem 0.375rem;
  overflow: hidden;
  font: inherit;
  font-size: 0.8125rem;
  line-height: 1.25;
  color: var(--muted);
  background: var(--bg);
  border: 1px solid var(--border);
  cursor: pointer;
}

.segmented__btn > .text-clamp {
  width: 100%;
}

.segmented__btn:first-child {
  margin-left: 0;
  border-radius: var(--radius) 0 0 var(--radius);
}

.segmented__btn:last-child {
  border-radius: 0 var(--radius) var(--radius) 0;
}

.segmented__btn:only-child {
  border-radius: var(--radius);
}

.segmented__btn:hover:not(.is-active):not(:disabled) {
  color: var(--text);
  background: var(--surface);
}

.segmented__btn.is-active {
  z-index: 1;
  color: #fff;
  background: var(--accent);
  border-color: var(--accent);
}

.segmented__btn:disabled {
  cursor: wait;
  opacity: 0.7;
}

.segmented__btn:focus-visible {
  outline: 2px solid var(--accent-text);
  outline-offset: 1px;
}

.companies-loading,
.companies-empty,
.vacancies-loading,
.vacancies-empty {
  margin: 0;
  color: var(--muted);
}

.companies-error,
.vacancies-error {
  margin: 0;
  color: var(--error);
}

.company-loading,
.company-error,
.vacancy-loading,
.vacancy-error {
  margin: 0;
  padding: 1.25rem;
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  box-shadow: var(--shadow);
  color: var(--muted);
}

.company-error,
.vacancy-error {
  color: var(--error);
}

.company-meta__mono,
.vacancy-meta__mono {
  font-family: ui-monospace, "Cascadia Code", "Source Code Pro", Menlo, monospace;
  font-size: 0.8125rem;
}

.company-card,
.vacancy-card {
  padding: 1.25rem 1.5rem;
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  box-shadow: var(--shadow);
}

.company-card__section,
.vacancy-card__section {
  margin-top: 1.5rem;
}

.company-card__section:first-of-type,
.vacancy-card__section:first-of-type {
  margin-top: 0;
}

.company-card__heading,
.vacancy-card__heading {
  margin: 0 0 0.75rem;
  font-size: 0.75rem;
  font-weight: 600;
  letter-spacing: 0.06em;
  text-transform: uppercase;
  color: var(--muted);
}

.company-card__name,
.vacancy-card__title {
  margin: 0 0 1.25rem;
  font-size: 1.5rem;
  font-weight: 600;
  line-height: 1.25;
  text-align: center;
}

.page__panel {
  margin-top: 1.5rem;
  padding: 1.25rem;
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  box-shadow: var(--shadow);
}

.saved-toast-stack {
  position: fixed;
  right: 1rem;
  bottom: 1rem;
  z-index: 10000;
  display: flex;
  flex-direction: column;
  align-items: flex-end;
  gap: 0.5rem;
  pointer-events: none;
}

.saved-toast {
  position: relative;
  isolation: isolate;
  box-sizing: border-box;
  width: min(250px, calc(100vw - 2rem));
  padding: 0.5rem 0.875rem;
  font-size: 0.875rem;
  font-weight: 400;
  color: #14532d;
  text-shadow: var(--glass-text-shadow);
  background: transparent;
  border: 1px solid color-mix(in srgb, #c5dcc9 88%, transparent);
  border-radius: var(--radius);
  box-shadow: var(--shadow-lg);
  overflow-wrap: break-word;
  opacity: 0;
  transform: translateY(0.5rem);
  transition:
    opacity 0.22s ease,
    transform 0.22s ease;
}

.saved-toast.is-visible {
  opacity: 1;
  transform: translateY(0);
}

.error-toast {
  color: #7f1d1d;
  border-color: color-mix(in srgb, #f5c2c2 88%, transparent);
}

.warn-toast {
  color: #713f12;
  border-color: color-mix(in srgb, #f5e6a8 88%, transparent);
}

@media (prefers-color-scheme: dark) {
  :root:not([data-theme="light"]) .saved-toast,
  :root[data-theme="dark"] .saved-toast {
    border-color: color-mix(in srgb, #2d4034 90%, transparent);
    color: #8fb99a;
  }

  :root:not([data-theme="light"]) .error-toast,
  :root[data-theme="dark"] .error-toast {
    border-color: color-mix(in srgb, #4a2d2d 90%, transparent);
    color: #d4a0a0;
  }

  :root:not([data-theme="light"]) .warn-toast,
  :root[data-theme="dark"] .warn-toast {
    border-color: color-mix(in srgb, #4a422d 90%, transparent);
    color: #d4c48a;
  }
}

@media (max-width: 1023px) {
  .saved-toast-stack {
    right: auto;
    left: 50%;
    transform: translateX(-50%);
    align-items: center;
  }
}

/* Expandable lists — unified rotating chevron (SPEC/req-ui.md) */
.expandable-chevron {
  flex-shrink: 0;
  width: 1rem;
  height: 1rem;
  background: var(--muted);
  mask: url("/icons/chevron-right-2.svg") center / contain no-repeat;
  -webkit-mask: url("/icons/chevron-right-2.svg") center / contain no-repeat;
  transition: transform 0.15s ease;
}

.expandable-chevron.is-open {
  transform: rotate(90deg);
}

.expandable-summary {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 0.5rem;
  list-style: none;
}

.expandable-summary::-webkit-details-marker {
  display: none;
}

.expandable-summary::after {
  content: "";
  flex-shrink: 0;
  width: 1rem;
  height: 1rem;
  background: var(--muted);
  mask: url("/icons/chevron-right-2.svg") center / contain no-repeat;
  -webkit-mask: url("/icons/chevron-right-2.svg") center / contain no-repeat;
  transition: transform 0.15s ease;
}

details[open] > .expandable-summary::after {
  transform: rotate(90deg);
}

/* Scroll regions — pages, modals, wide blocks (SPEC/req-ui.md) */
.scroll-region {
  position: relative;
  min-width: 0;
}

.scroll-region--x {
  max-width: 100%;
}

.scroll-region--x > .scroll-region__body {
  overflow-x: auto;
}

.scroll-region__body {
  min-width: 0;
  min-height: 0;
}

.scroll-region__controls {
  position: absolute;
  right: 0.625rem;
  bottom: 0.625rem;
  z-index: 2;
  display: flex;
  gap: 0.25rem;
  pointer-events: none;
}

.scroll-region__controls--y {
  flex-direction: column;
}

.scroll-region__controls--x {
  flex-direction: row;
  top: 100%;
  bottom: auto;
  left: 0.625rem;
  right: auto;
  margin-top: 0.25rem;
}

.scroll-region--x:has(.scroll-region__body--can-scroll-x) {
  margin-bottom: 2.25rem;
}

.page-scroll__controls-host {
  position: fixed;
  right: 0.625rem;
  bottom: 0.625rem;
  z-index: 5;
  width: 0;
  height: 0;
  pointer-events: none;
}

.scroll-region__controls--page {
  position: absolute;
  right: 0;
  bottom: 0;
}

.scroll-region__btn {
  position: relative;
  isolation: isolate;
  pointer-events: auto;
  display: flex;
  align-items: center;
  justify-content: center;
  width: 2rem;
  height: 2rem;
  padding: 0;
  color: var(--text);
  text-shadow: var(--scroll-btn-text-shadow, var(--glass-text-shadow));
  background: transparent;
  border: 1px solid color-mix(in srgb, var(--glass-border) 88%, var(--text));
  border-radius: var(--radius);
  box-shadow: var(--shadow-lg);
  cursor: pointer;
}

.scroll-region__btn:focus-visible {
  outline: 2px solid var(--accent-text);
  outline-offset: 1px;
}

.scroll-region__btn.is-hidden {
  visibility: hidden;
  pointer-events: none;
}

.scroll-region__chevron {
  display: block;
  width: 1rem;
  height: 1rem;
  background: currentColor;
  mask: url("/icons/chevron-right-2.svg") center / contain no-repeat;
  -webkit-mask: url("/icons/chevron-right-2.svg") center / contain no-repeat;
}

.scroll-region__chevron--up {
  transform: rotate(-90deg);
}

.scroll-region__chevron--down {
  transform: rotate(90deg);
}

.scroll-region__chevron--left {
  mask: url("/icons/chevron-left-2.svg") center / contain no-repeat;
  -webkit-mask: url("/icons/chevron-left-2.svg") center / contain no-repeat;
  transform: none;
}

.scroll-region__chevron--right {
  transform: none;
}

.scroll-region__body--can-scroll-y {
  overflow-y: scroll;
  scrollbar-gutter: stable;
  scrollbar-width: thin;
  scrollbar-color: color-mix(in srgb, var(--muted) 65%, var(--border))
    color-mix(in srgb, var(--muted) 28%, transparent);
}

.scroll-region__body--can-scroll-y::-webkit-scrollbar {
  width: 0.5rem;
}

.scroll-region__body--can-scroll-y::-webkit-scrollbar-track {
  background: color-mix(in srgb, var(--muted) 22%, transparent);
  border-radius: 999px;
}

.scroll-region__body--can-scroll-y::-webkit-scrollbar-thumb {
  background: color-mix(in srgb, var(--muted) 65%, var(--border));
  border-radius: 999px;
}

html.site-nav-drawer-open.scroll-region__body--can-scroll-y {
  overflow: hidden;
}

.scroll-region__body--can-scroll-x {
  overflow-x: scroll;
  scrollbar-gutter: stable;
  scrollbar-width: thin;
  scrollbar-color: color-mix(in srgb, var(--muted) 65%, var(--border))
    color-mix(in srgb, var(--muted) 28%, transparent);
}

.scroll-region__body--can-scroll-x::-webkit-scrollbar {
  height: 0.5rem;
}

.scroll-region__body--can-scroll-x::-webkit-scrollbar-track {
  background: color-mix(in srgb, var(--muted) 22%, transparent);
  border-radius: 999px;
}

.scroll-region__body--can-scroll-x::-webkit-scrollbar-thumb {
  background: color-mix(in srgb, var(--muted) 65%, var(--border));
  border-radius: 999px;
}

/* Long text in short blocks (SPEC/req-ui.md) */
.text-clamp {
  display: block;
  min-width: 0;
  max-width: 100%;
  overflow: hidden;
  text-overflow: ellipsis;
  white-space: nowrap;
}

.text-clamp__tooltip {
  position: relative;
  isolation: isolate;
  z-index: 250;
  margin: 0;
  padding: 0.375rem 0.5rem;
  font-size: 0.8125rem;
  line-height: 1.4;
  color: var(--text);
  text-shadow: var(--glass-text-shadow);
  background: transparent;
  border: 1px solid var(--glass-border);
  border-radius: var(--radius);
  box-shadow: var(--shadow-lg);
  pointer-events: none;
  white-space: pre-wrap;
  word-break: break-word;
}

@media (max-width: 40rem) {
  .segmented__btn {
    padding-inline: 0.25rem;
    font-size: 0.75rem;
  }
}