.page-header {
  position: sticky;
  top: 0;
  z-index: 1000;
  backdrop-filter: blur(10px);
  background:
    linear-gradient(180deg, rgba(8, 12, 24, 0.94), rgba(8, 12, 24, 0.88));
  border-bottom: 1px solid rgba(255, 255, 255, 0.08);
  box-shadow: 0 12px 28px rgba(3, 5, 11, 0.18);
}

body[data-layout-context="problem"] .site-header,
body[data-layout-context="problem"] .page-header {
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  width: 100%;
  z-index: 1000;
}

.problem-header-inner {
  min-height: 5.6rem;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 1.2rem;
}

.problem-header-brand {
  display: flex;
  align-items: center;
  gap: 1rem;
  min-width: 0;
}

.problem-logo {
  display: inline-flex;
  align-items: center;
  flex-shrink: 0;
}

.problem-logo img {
  display: block;
  width: auto;
  height: 3.1rem;
  max-width: 100%;
}

.problem-header-kicker {
  display: inline-flex;
  align-items: center;
  gap: 0.55rem;
  font-family: var(--font-head);
  font-size: 0.84rem;
  letter-spacing: 0.08em;
  text-transform: uppercase;
  color: var(--muted);
  white-space: nowrap;
}

.problem-header-kicker::before {
  content: "";
  width: 0.45rem;
  height: 0.45rem;
  border: 1px solid rgba(37, 208, 208, 0.85);
  box-shadow: 0 0 10px rgba(37, 208, 208, 0.28);
}

.problem-header-actions {
  display: flex;
  align-items: center;
  gap: 0.85rem;
  flex-wrap: wrap;
  justify-content: flex-end;
}

.overview-link {
  display: inline-flex;
  align-items: center;
  gap: 0.42rem;
  color: var(--muted);
  text-decoration: none;
  font-size: 0.95rem;
  line-height: 1;
  padding: 0.45rem 0;
  transition:
    color 220ms ease,
    transform 220ms ease;
}

.overview-link::before {
  content: "←";
  font-size: 0.95rem;
  color: var(--accent-cyan);
}

.overview-link__text {
  border-bottom: 1px solid rgba(255, 255, 255, 0.14);
  transition: border-color 220ms ease;
}

.overview-link:hover,
.overview-link:focus-visible {
  color: var(--text);
  transform: translateX(-2px);
}

.overview-link:hover .overview-link__text,
.overview-link:focus-visible .overview-link__text {
  border-bottom-color: rgba(37, 208, 208, 0.5);
}

.problem-header-cta {
  min-height: 2.75rem;
  padding-inline: 1rem;
  white-space: nowrap;
  border-radius: var(--radius-control);
}

.problem-nav-toggle,
.problem-mobile-menu {
  display: none;
}

body[data-layout-context="problem"] main {
  padding-top: 1rem;
}

body[data-layout-context="problem"] [data-include="header"] {
  display: block;
  min-height: 5.6rem;
}

.motion-reveal {
  opacity: 0;
  transform: translateY(18px);
  filter: blur(6px);
  transition:
    opacity 720ms cubic-bezier(0.22, 1, 0.36, 1),
    transform 720ms cubic-bezier(0.22, 1, 0.36, 1),
    filter 720ms cubic-bezier(0.22, 1, 0.36, 1);
  will-change: opacity, transform, filter;
}

.motion-reveal.from-left {
  transform: translateX(-22px);
}

.motion-reveal.from-right {
  transform: translateX(22px);
}

.motion-reveal.is-visible {
  opacity: 1;
  transform: translate(0, 0);
  filter: blur(0);
}

.motion-stagger > * {
  opacity: 0;
  transform: translateY(16px);
  transition:
    opacity 620ms cubic-bezier(0.22, 1, 0.36, 1),
    transform 620ms cubic-bezier(0.22, 1, 0.36, 1);
}

.motion-stagger.is-visible > *:nth-child(1) { transition-delay: 60ms; }
.motion-stagger.is-visible > *:nth-child(2) { transition-delay: 120ms; }
.motion-stagger.is-visible > *:nth-child(3) { transition-delay: 180ms; }
.motion-stagger.is-visible > *:nth-child(4) { transition-delay: 240ms; }
.motion-stagger.is-visible > *:nth-child(5) { transition-delay: 300ms; }
.motion-stagger.is-visible > *:nth-child(6) { transition-delay: 360ms; }

.motion-stagger.is-visible > * {
  opacity: 1;
  transform: translateY(0);
}

.motion-soft-glow {
  transition:
    box-shadow 500ms ease,
    border-color 500ms ease,
    background-color 500ms ease;
}

.motion-soft-glow.is-visible {
  box-shadow: 0 14px 34px rgba(5, 7, 15, 0.16);
}

body[data-layout-context="problem"].problem-page-transition main {
  opacity: 0;
  transform: translateY(10px);
  transition:
    opacity 320ms ease,
    transform 360ms cubic-bezier(0.22, 1, 0.36, 1);
}

body[data-layout-context="problem"].problem-page-transition.is-page-ready main {
  opacity: 1;
  transform: translateY(0);
}

body[data-layout-context="problem"].problem-page-transition.is-page-leaving main {
  opacity: 0;
  transform: translateY(8px);
  pointer-events: none;
}

.problem-topic-nav {
  margin-top: 1.15rem;
  margin-bottom: 1.85rem;
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 0.58rem;
  overflow-x: auto;
  overflow-y: hidden;
  padding: 0.45rem 0 0.4rem;
  scrollbar-width: thin;
  scrollbar-color: rgba(37, 208, 208, 0.35) transparent;
  border-top: 1px solid rgba(255, 255, 255, 0.08);
  border-bottom: 1px solid rgba(255, 255, 255, 0.06);
  background:
    linear-gradient(90deg, rgba(37, 208, 208, 0.04), rgba(139, 92, 246, 0.03));
  border-radius: var(--radius-card);
}

.problem-topic-nav::-webkit-scrollbar {
  height: 8px;
}

.problem-topic-nav::-webkit-scrollbar-thumb {
  background: rgba(37, 208, 208, 0.28);
}

.problem-topic-nav__link {
  flex: 0 0 auto;
  display: inline-flex;
  align-items: center;
  justify-content: center;
  min-height: 2.7rem;
  padding: 0.7rem 0.92rem;
  color: var(--muted);
  font-size: 0.96rem;
  line-height: 1.25;
  text-align: center;
  white-space: nowrap;
  border: 1px solid rgba(255, 255, 255, 0.08);
  background: rgba(11, 16, 32, 0.36);
  border-radius: var(--radius-control);
  transition:
    color 220ms ease,
    border-color 220ms ease,
    background-color 220ms ease,
    transform 220ms ease,
    box-shadow 220ms ease;
}

.problem-topic-nav__link:hover,
.problem-topic-nav__link:focus-visible {
  color: var(--text);
  border-color: rgba(255, 255, 255, 0.18);
  background: rgba(18, 24, 43, 0.72);
  transform: translateY(-1px);
}

.problem-topic-nav__link.active {
  color: var(--text);
  border-color: rgba(37, 208, 208, 0.42);
  background:
    linear-gradient(120deg, rgba(37, 208, 208, 0.14), rgba(139, 92, 246, 0.14));
  box-shadow: inset 0 0 0 1px rgba(37, 208, 208, 0.08);
}

.problem-pager {
  margin-top: 1.7rem;
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 0.85rem;
}

.problem-pager:has(.problem-pager__prev):not(:has(.problem-pager__next)),
.problem-pager:has(.problem-pager__next):not(:has(.problem-pager__prev)) {
  grid-template-columns: 1fr;
}

.problem-pager:has(.problem-pager__next):not(:has(.problem-pager__prev)) {
  justify-items: end;
}

.problem-pager__prev,
.problem-pager__next {
  display: flex;
  flex-direction: column;
  justify-content: center;
  min-width: 0;
  gap: 0.24rem;
  padding: 0.3rem 0.2rem;
  border-radius: 0;
  text-decoration: none;
  color: inherit;
  border: 0;
  background: transparent;
  border-bottom: 1px solid transparent;
  transition:
    border-color 220ms ease,
    box-shadow 220ms ease,
    color 220ms ease,
    transform 220ms ease;
}

.problem-pager__prev {
  border-bottom-color: rgba(255, 255, 255, 0.16);
}

.problem-pager__next {
  border-bottom-color: rgba(37, 208, 208, 0.24);
}

.problem-pager__prev:hover,
.problem-pager__prev:focus-visible,
.problem-pager__next:hover,
.problem-pager__next:focus-visible {
  transform: translateY(-2px);
  color: var(--text);
  box-shadow: none;
}

.problem-pager__prev:hover,
.problem-pager__prev:focus-visible {
  border-color: rgba(255, 255, 255, 0.22);
}

.problem-pager__next:hover,
.problem-pager__next:focus-visible {
  border-color: rgba(37, 208, 208, 0.46);
}

.problem-pager__label {
  display: flex;
  align-items: center;
  gap: 0.38rem;
  width: 100%;
  max-width: 100%;
  white-space: normal;
  overflow-wrap: anywhere;
  font-family: var(--font-head);
  font-size: 0.82rem;
  letter-spacing: 0.06em;
  text-transform: uppercase;
  color: var(--muted);
}

.problem-pager__title {
  font-size: 1rem;
  line-height: 1.3;
  color: var(--text);
  text-decoration: none;
  text-underline-offset: 0.2em;
  text-decoration-color: transparent;
  transition: text-decoration-color 220ms ease, color 220ms ease;
}

.problem-pager__prev:hover .problem-pager__title,
.problem-pager__prev:focus-visible .problem-pager__title,
.problem-pager__next:hover .problem-pager__title,
.problem-pager__next:focus-visible .problem-pager__title {
  text-decoration-line: underline;
  text-decoration-color: currentColor;
}

.problem-pager__prev {
  text-align: left;
}

.problem-pager__prev .problem-pager__label::before {
  content: "";
  width: 0.5rem;
  height: 0.5rem;
  display: inline-block;
  flex: 0 0 auto;
  border-top: 2px solid var(--accent-cyan);
  border-right: 2px solid var(--accent-cyan);
  transform: rotate(-135deg);
  margin-top: 1px;
}

.problem-pager__prev .problem-pager__label {
  justify-content: flex-start;
}

.problem-pager__next {
  text-align: right;
}

.problem-pager:has(.problem-pager__next):not(:has(.problem-pager__prev)) .problem-pager__next {
  width: min(100%, 28rem);
}

.problem-pager__next .problem-pager__label::after {
  content: "";
  width: 0.5rem;
  height: 0.5rem;
  display: inline-block;
  flex: 0 0 auto;
  border-top: 2px solid var(--accent-cyan);
  border-right: 2px solid var(--accent-cyan);
  transform: rotate(45deg);
  margin-top: 1px;
}

.problem-pager__next .problem-pager__label {
  justify-content: flex-end;
}

@media (max-width: 980px) {
  .problem-header-inner {
    min-height: auto;
    padding: 0.9rem 0;
    flex-direction: column;
    align-items: flex-start;
  }

  .problem-header-actions {
    width: 100%;
    justify-content: space-between;
  }

  .problem-logo img {
    height: 2.85rem;
  }
}

@media (max-width: 700px) {
  .problem-header-inner {
    min-height: auto;
    padding: 0.72rem 0;
    flex-direction: row;
    align-items: center;
    justify-content: space-between;
  }

  .problem-header-actions {
    display: none;
  }

  .problem-logo img {
    height: 2.72rem;
  }

  .problem-nav-toggle {
    display: inline-flex;
    flex-direction: column;
    justify-content: center;
    align-items: center;
    gap: 7px;
    width: 56px;
    height: 56px;
    border: 1px solid rgba(43, 224, 255, 0.24);
    border-radius: var(--radius-pill);
    background:
      linear-gradient(180deg, rgba(17, 26, 55, 0.92), rgba(8, 14, 32, 0.94));
    box-shadow:
      0 10px 30px rgba(0, 0, 0, 0.28),
      inset 0 1px 0 rgba(255, 255, 255, 0.06),
      0 0 0 1px rgba(255, 255, 255, 0.02);
    backdrop-filter: blur(10px);
    -webkit-backdrop-filter: blur(10px);
    padding: 0;
    margin-right: max(0.35rem, env(safe-area-inset-right));
    cursor: pointer;
    transition:
      transform 180ms ease,
      box-shadow 180ms ease,
      border-color 180ms ease,
      background 180ms ease;
  }

  .problem-nav-toggle:hover {
    transform: translateY(-1px);
    border-color: rgba(43, 224, 255, 0.45);
    box-shadow:
      0 14px 34px rgba(0, 0, 0, 0.34),
      0 0 18px rgba(43, 224, 255, 0.14),
      inset 0 1px 0 rgba(255, 255, 255, 0.08);
  }

  .problem-nav-toggle:active {
    transform: translateY(0);
  }

  .problem-nav-toggle span {
    display: block;
    width: 24px;
    height: 2.5px;
    margin: 0;
    border-radius: var(--radius-pill);
    background: linear-gradient(
      90deg,
      rgba(240, 248, 255, 0.95),
      rgba(43, 224, 255, 0.92)
    );
    box-shadow: 0 0 10px rgba(43, 224, 255, 0.16);
    transition:
      transform 220ms ease,
      opacity 180ms ease,
      width 180ms ease,
      background 180ms ease;
  }

  .problem-nav-toggle span:nth-child(2) {
    width: 18px;
  }

  .problem-nav-toggle:hover span:nth-child(2) {
    width: 24px;
  }

  .problem-nav-toggle:focus-visible {
    outline: none;
    box-shadow:
      0 0 0 3px rgba(43, 224, 255, 0.18),
      0 14px 34px rgba(0, 0, 0, 0.34),
      0 0 18px rgba(43, 224, 255, 0.14);
  }

  .problem-nav-toggle.is-active span:nth-child(1) {
    transform: translateY(9.5px) rotate(45deg);
  }

  .problem-nav-toggle.is-active span:nth-child(2) {
    opacity: 0;
    transform: scaleX(0.3);
  }

  .problem-nav-toggle.is-active span:nth-child(3) {
    transform: translateY(-9.5px) rotate(-45deg);
  }

  .problem-mobile-menu {
    position: fixed;
    left: 0;
    right: 0;
    top: calc(5.3rem - 2px);
    bottom: 0;
    z-index: 1100;
    display: none;
    flex-direction: column;
    padding: 0.8rem 0.72rem calc(0.72rem + env(safe-area-inset-bottom));
    background: linear-gradient(180deg, rgba(8, 12, 24, 0.94), rgba(8, 12, 24, 0.98));
    backdrop-filter: blur(10px);
    border-top: 0;
  }

  .problem-mobile-menu.is-open {
    display: flex;
  }

  .problem-mobile-menu-nav {
    display: grid;
    gap: 0.45rem;
  }

  .problem-mobile-menu-nav a {
    display: block;
    width: 100%;
    min-height: 2.7rem;
    padding: 0.68rem 0.82rem;
    border: 1px solid rgba(255, 255, 255, 0.12);
    border-radius: 12px;
    background: rgba(11, 16, 32, 0.62);
    color: var(--text);
    text-decoration: none;
    font-size: 0.92rem;
    line-height: 1.3;
  }

  .problem-mobile-menu-nav a.active {
    border-color: rgba(37, 208, 208, 0.45);
    background: linear-gradient(120deg, rgba(37, 208, 208, 0.14), rgba(139, 92, 246, 0.14));
  }

  .problem-mobile-menu-footer {
    margin-top: auto;
    padding-top: 0.8rem;
  }

  .problem-mobile-menu-back {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    width: 100%;
    min-height: 2.7rem;
    border: 1px solid rgba(255, 255, 255, 0.16);
    border-radius: 12px;
    color: var(--text);
    text-decoration: none;
    background: rgba(11, 16, 32, 0.62);
  }

  body.problem-menu-open {
    overflow: hidden;
  }

  .problem-topic-nav {
    display: none !important;
  }

  .problem-pager {
    grid-template-columns: repeat(2, minmax(0, 1fr));
    gap: 0.7rem;
  }

  .problem-pager__prev,
  .problem-pager__next {
    min-height: auto;
    padding: 0;
    border-bottom: 0;
    box-shadow: none;
    text-align: left;
  }

  .problem-pager:has(.problem-pager__next):not(:has(.problem-pager__prev)) {
    justify-items: end;
  }

  .problem-pager:has(.problem-pager__next):not(:has(.problem-pager__prev)) .problem-pager__next {
    width: auto;
  }

  .problem-pager:has(.problem-pager__prev):not(:has(.problem-pager__next)) {
    justify-items: start;
  }

  .problem-pager:has(.problem-pager__prev):not(:has(.problem-pager__next)) .problem-pager__prev {
    width: auto;
  }

  .problem-pager__prev:hover .problem-pager__title,
  .problem-pager__prev:focus-visible .problem-pager__title,
  .problem-pager__next:hover .problem-pager__title,
  .problem-pager__next:focus-visible .problem-pager__title {
    text-decoration: none;
  }

  .problem-pager__title {
    text-decoration: none;
    text-underline-offset: 0;
    width: 100%;
    text-align: center;
  }

  .problem-pager__next {
    text-align: right;
    justify-self: end;
  }

  .problem-pager__prev {
    text-align: left;
    justify-self: start;
  }

  .content-main,
  .content-main-panel,
  .content-cause-panel,
  .content-side-panel {
    padding: 0.82rem;
    border-radius: 16px;
  }

  .content-free,
  .content-free-block {
    padding-top: 0.2rem;
  }

  .content-impact,
  .content-free-block.accent {
    padding: 0.78rem 0.82rem 0.84rem;
    border-left-width: 2px;
    border-radius: 0 12px 12px 0;
  }

  .performance-actions,
  .conversion-actions,
  .technical-actions,
  .seo-actions,
  .contact-actions {
    display: grid;
    grid-template-columns: 1fr;
    gap: 0.6rem;
  }

  .performance-actions .btn,
  .conversion-actions .btn,
  .technical-actions .btn,
  .seo-actions .btn,
  .contact-actions .btn {
    width: 100%;
  }
}

@media (max-width: 520px) {
  .problem-header-inner {
    padding: 0.64rem 0;
  }

  .problem-logo img {
    height: 2.55rem;
  }

  .problem-mobile-menu {
    top: calc(5rem - 2px);
    padding-inline: 0.62rem;
  }

  .problem-mobile-menu-nav a {
    min-height: 2.55rem;
    padding: 0.62rem 0.72rem;
    font-size: 0.88rem;
  }

  .problem-pager {
    gap: 0.62rem;
  }

  .problem-pager__title {
    font-size: 0.94rem;
    line-height: 1.28;
  }
}

@media (prefers-reduced-motion: reduce) {
  .motion-reveal,
  .motion-stagger > * {
    opacity: 1 !important;
    transform: none !important;
    filter: none !important;
    transition: none !important;
  }

  .motion-soft-glow {
    transition: none !important;
  }

  body[data-layout-context="problem"].problem-page-transition main {
    opacity: 1;
    transform: none;
    transition: none;
  }

  body[data-layout-context="problem"].problem-page-transition.is-page-leaving main {
    opacity: 1;
    transform: none;
    pointer-events: auto;
  }
}