/* ==========================================================================
   layout.css — header, navigation, footer, page scaffolding
   ========================================================================== */

/* --------------------------------------------------------------------------
   Scroll progress bar
   -------------------------------------------------------------------------- */
.progress-bar {
  position: fixed;
  inset-block-start: 0;
  inset-inline-start: 0;
  height: 3px;
  width: 100%;
  transform: scaleX(0);
  transform-origin: 0 50%;
  background: linear-gradient(90deg, var(--brand-500), var(--accent-500));
  z-index: 120;
  pointer-events: none;
}

/* --------------------------------------------------------------------------
   Header
   -------------------------------------------------------------------------- */
.site-header {
  position: sticky;
  inset-block-start: 0;
  z-index: 100;
  background: color-mix(in srgb, var(--bg) 82%, transparent);
  border-bottom: 1px solid transparent;
  transition: background var(--dur) var(--ease),
    border-color var(--dur) var(--ease), box-shadow var(--dur) var(--ease),
    backdrop-filter var(--dur) var(--ease);
}

@supports (backdrop-filter: blur(8px)) {
  .site-header {
    backdrop-filter: blur(12px) saturate(140%);
  }
}

.site-header.is-stuck {
  border-bottom-color: var(--border);
  box-shadow: var(--shadow-sm);
}

.site-header__inner {
  min-height: var(--header-h);
  display: flex;
  align-items: center;
  gap: var(--sp-5);
  justify-content: space-between;
}

/* Brand / wordmark */
.brand {
  display: inline-flex;
  align-items: center;
  gap: var(--sp-3);
  text-decoration: none;
  color: var(--text);
  min-width: 0;
}

.brand:hover {
  color: var(--text);
}

.brand__mark {
  width: 40px;
  height: 40px;
  border-radius: 50%;
  display: grid;
  place-items: center;
  background: linear-gradient(150deg, var(--brand-500), var(--brand-600));
  color: #fff;
  font-family: var(--font-display);
  font-size: 0.95rem;
  font-weight: 600;
  letter-spacing: 0.02em;
  box-shadow: var(--shadow-sm);
  transition: transform var(--dur) var(--ease);
}

.brand:hover .brand__mark {
  transform: rotate(-6deg) scale(1.04);
}

[data-theme="dark"] .brand__mark {
  color: #0e1116;
}

.brand__text {
  display: flex;
  flex-direction: column;
  line-height: 1.15;
  min-width: 0;
}

.brand__name {
  font-family: var(--font-display);
  font-size: 1.02rem;
  font-weight: 600;
  letter-spacing: -0.01em;
  white-space: nowrap;
  overflow: hidden;
  text-overflow: ellipsis;
}

.brand__role {
  font-size: 0.68rem;
  letter-spacing: 0.12em;
  text-transform: uppercase;
  color: var(--text-muted);
}

/* Navigation */
.nav {
  display: flex;
  align-items: center;
  gap: var(--sp-2);
}

.nav__list {
  display: flex;
  align-items: center;
  gap: var(--sp-1);
  margin: 0;
  padding: 0;
  list-style: none;
}

.nav__link {
  display: inline-block;
  position: relative;
  padding: var(--sp-2) var(--sp-3);
  border-radius: var(--r-pill);
  font-size: var(--step--1);
  font-weight: 550;
  color: var(--text-soft);
  text-decoration: none;
  transition: color var(--dur-fast) var(--ease),
    background var(--dur-fast) var(--ease);
}

.nav__link::after {
  content: "";
  position: absolute;
  inset-block-end: 3px;
  inset-inline: var(--sp-3);
  height: 2px;
  background: var(--accent-500);
  border-radius: 2px;
  transform: scaleX(0);
  transform-origin: 50% 50%;
  transition: transform var(--dur) var(--ease);
}

.nav__link:hover {
  color: var(--text);
  background: var(--wash);
}

.nav__link:hover::after,
.nav__link[aria-current="page"]::after {
  transform: scaleX(1);
}

.nav__link[aria-current="page"] {
  color: var(--text);
  font-weight: 650;
}

/* Header actions */
.header-actions {
  display: flex;
  align-items: center;
  gap: var(--sp-2);
  flex-shrink: 0;
  margin-inline-start: auto;
}

@media (max-width: 36rem) {
  /* keep the burger reachable and the full name visible on phones */
  .brand__mark {
    width: 34px;
    height: 34px;
    font-size: 0.82rem;
  }

  .brand__name {
    font-size: 0.9rem;
    line-height: 1.12;
    white-space: normal;
    overflow: visible;
    text-overflow: clip;
  }

  .brand__role {
    display: none;
  }

  .site-header__inner {
    gap: var(--sp-3);
  }
}

.icon-btn {
  width: 40px;
  height: 40px;
  display: grid;
  place-items: center;
  border-radius: 50%;
  border: 1px solid var(--border);
  background: var(--surface);
  color: var(--text-soft);
  transition: color var(--dur-fast) var(--ease),
    border-color var(--dur-fast) var(--ease), transform var(--dur-fast) var(--ease),
    background var(--dur-fast) var(--ease);
}

.icon-btn:hover {
  color: var(--accent-500);
  border-color: var(--border-strong);
  transform: translateY(-1px);
}

.icon-btn svg {
  width: 18px;
  height: 18px;
}

.theme-toggle .icon-moon {
  display: none;
}

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

[data-theme="dark"] .theme-toggle .icon-moon {
  display: block;
}

/* Burger (mobile) */
.nav-toggle {
  display: none;
}

.nav-toggle__bars {
  display: block;
  width: 18px;
  height: 12px;
  position: relative;
}

.nav-toggle__bars span {
  position: absolute;
  inset-inline: 0;
  height: 2px;
  border-radius: 2px;
  background: currentColor;
  transition: transform var(--dur) var(--ease), opacity var(--dur-fast) var(--ease);
}

.nav-toggle__bars span:nth-child(1) {
  top: 0;
}
.nav-toggle__bars span:nth-child(2) {
  top: 5px;
}
.nav-toggle__bars span:nth-child(3) {
  top: 10px;
}

.nav-toggle[aria-expanded="true"] .nav-toggle__bars span:nth-child(1) {
  transform: translateY(5px) rotate(45deg);
}
.nav-toggle[aria-expanded="true"] .nav-toggle__bars span:nth-child(2) {
  opacity: 0;
}
.nav-toggle[aria-expanded="true"] .nav-toggle__bars span:nth-child(3) {
  transform: translateY(-5px) rotate(-45deg);
}

@media (max-width: 60rem) {
  .nav-toggle {
    display: grid;
  }

  .nav {
    position: fixed;
    inset-block-start: var(--header-h);
    inset-inline: 0;
    display: block;
    padding: var(--sp-4) var(--sp-5) var(--sp-6);
    background: var(--bg-alt);
    border-bottom: 1px solid var(--border);
    box-shadow: var(--shadow-lg);
    transform: translateY(-8px);
    opacity: 0;
    visibility: hidden;
    transition: opacity var(--dur) var(--ease), transform var(--dur) var(--ease),
      visibility var(--dur) linear;
    max-height: calc(100dvh - var(--header-h));
    overflow-y: auto;
  }

  .nav.is-open {
    opacity: 1;
    visibility: visible;
    transform: translateY(0);
  }

  .nav__list {
    flex-direction: column;
    align-items: stretch;
    gap: 2px;
  }

  .nav__link {
    display: block;
    padding: var(--sp-3) var(--sp-4);
    border-radius: var(--r-md);
    font-size: var(--step-0);
  }

  .nav__link::after {
    display: none;
  }

  .nav__link[aria-current="page"] {
    background: var(--wash);
    color: var(--brand-500);
  }

  .nav__cta {
    margin-top: var(--sp-4);
  }
}

/* --------------------------------------------------------------------------
   Page hero
   -------------------------------------------------------------------------- */
.page-hero {
  position: relative;
  padding-block: var(--sp-8) var(--sp-7);
  overflow: hidden;
  border-bottom: 1px solid var(--border);
  background: linear-gradient(180deg, var(--wash), transparent 70%);
}

.page-hero::after {
  content: "";
  position: absolute;
  inset-block-start: -40%;
  inset-inline-end: -10%;
  width: 34rem;
  height: 34rem;
  border-radius: 50%;
  background: radial-gradient(
    circle,
    var(--wash-accent) 0%,
    transparent 65%
  );
  pointer-events: none;
}

.page-hero__inner {
  position: relative;
  z-index: 1;
  max-width: 68ch;
}

.page-hero h1 {
  font-size: var(--step-4);
}

.page-hero p {
  margin-top: var(--sp-4);
}

.breadcrumb {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: var(--sp-2);
  font-size: var(--step--1);
  color: var(--text-muted);
  margin-bottom: var(--sp-4);
}

.breadcrumb a {
  color: var(--text-muted);
  text-decoration: none;
}

.breadcrumb a:hover {
  color: var(--accent-500);
}

.breadcrumb span[aria-hidden="true"] {
  opacity: 0.6;
}

/* --------------------------------------------------------------------------
   Footer
   -------------------------------------------------------------------------- */
.site-footer {
  margin-top: var(--sp-8);
  background: var(--bg-alt);
  border-top: 1px solid var(--border);
  padding-block: var(--sp-7) var(--sp-5);
}

.footer-grid {
  display: grid;
  grid-template-columns: 1.4fr 1fr 1fr;
  gap: var(--sp-6);
}

@media (max-width: 52rem) {
  .footer-grid {
    grid-template-columns: 1fr 1fr;
  }
  .footer-brand {
    grid-column: 1 / -1;
  }
}

@media (max-width: 34rem) {
  .footer-grid {
    grid-template-columns: 1fr;
  }
}

.footer-brand p {
  margin-top: var(--sp-4);
  font-size: var(--step--1);
  color: var(--text-muted);
  max-width: 34ch;
}

.footer-col h2 {
  font-family: var(--font-body);
  font-size: var(--step--2);
  letter-spacing: 0.14em;
  text-transform: uppercase;
  color: var(--text-muted);
  margin-bottom: var(--sp-4);
}

.footer-col ul {
  display: grid;
  gap: var(--sp-2);
}

.footer-col a {
  font-size: var(--step--1);
  color: var(--text-soft);
  text-decoration: none;
  transition: color var(--dur-fast) var(--ease),
    padding-inline-start var(--dur-fast) var(--ease);
}

.footer-col a:hover {
  color: var(--accent-500);
  padding-inline-start: 4px;
}

.footer-bottom {
  margin-top: var(--sp-6);
  padding-top: var(--sp-5);
  border-top: 1px solid var(--border);
  display: flex;
  flex-wrap: wrap;
  gap: var(--sp-3) var(--sp-5);
  align-items: center;
  justify-content: space-between;
  font-size: var(--step--1);
  color: var(--text-muted);
}

.footer-bottom__note {
  display: inline-flex;
  align-items: center;
  gap: var(--sp-2);
}

.footer-bottom__dot {
  width: 7px;
  height: 7px;
  border-radius: 50%;
  background: var(--ok);
  box-shadow: 0 0 0 3px color-mix(in srgb, var(--ok) 22%, transparent);
}

/* --------------------------------------------------------------------------
   Back to top
   -------------------------------------------------------------------------- */
.to-top {
  position: fixed;
  inset-block-end: var(--sp-5);
  inset-inline-end: var(--sp-5);
  width: 44px;
  height: 44px;
  display: grid;
  place-items: center;
  border-radius: 50%;
  background: var(--brand-500);
  color: var(--on-brand);
  border: 0;
  box-shadow: var(--shadow-md);
  opacity: 0;
  visibility: hidden;
  transform: translateY(10px);
  transition: opacity var(--dur) var(--ease), transform var(--dur) var(--ease),
    visibility var(--dur) linear, background var(--dur-fast) var(--ease);
  z-index: 90;
}

.to-top:hover {
  background: var(--brand-600);
}

.to-top.is-visible {
  opacity: 1;
  visibility: visible;
  transform: translateY(0);
}

.to-top svg {
  width: 18px;
  height: 18px;
}

/* Content remains visible even if scripting or animation fails. */
.reveal {
  opacity: 1;
  transform: none;
}

/* Without JavaScript, navigation stays available in the document flow. */
.no-js .theme-toggle,
.no-js .nav-toggle,
.no-js [data-copy] {
  display: none;
}

@media (max-width: 60rem) {
  .no-js .site-header__inner {
    flex-wrap: wrap;
  }

  .no-js .nav {
    position: static;
    flex-basis: 100%;
    order: 3;
    max-height: none;
    overflow: visible;
    opacity: 1;
    visibility: visible;
    transform: none;
    box-shadow: none;
    padding: var(--sp-2) 0;
  }
}