/* ============================================================
   header.css — sticky glass header, CSS-letter logo, nav,
   hamburger, mobile overlay
   ============================================================ */

.site-header {
  position: sticky;
  top: 0;
  z-index: 100;
  background-color: rgba(10, 14, 20, 0.55);
  backdrop-filter: blur(12px);
  -webkit-backdrop-filter: blur(12px);
  border-bottom: 1px solid transparent;
  transition: background-color var(--motion-med) var(--ease-out),
    border-color var(--motion-med) var(--ease-out);
}

.site-header.is-scrolled {
  background-color: rgba(10, 14, 20, 0.82);
  backdrop-filter: blur(20px);
  -webkit-backdrop-filter: blur(20px);
  border-bottom-color: var(--color-border);
}

.header-inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: var(--space-4);
  width: 90vw;
  max-width: none;
  height: var(--header-height);
  margin-inline: auto;
}

/* ------------------------------------------------------------
   CSS-letter logo — adapted from /var/www/html/css/styles.css
   (.logo_style, .text_title, .text_background, .logo, .logo_fondo)
   Colors adapted for dark theme visibility.
   ------------------------------------------------------------ */
.logo-link {
  display: inline-flex;
  align-items: center;
  flex-shrink: 0;
}

.logo_style {
  display: flex;
  position: relative;
  width: 150px;
  align-items: center;
  justify-content: center;
}

.text_background {
  text-align: center;
  font-weight: 800;
  letter-spacing: -0.02em;
  line-height: 1;
}

.logo_fondo {
  font-size: 2.5rem;
}

.logo_fondo.white {
  color: rgba(255, 255, 255, 0.14);
}

.text_title {
  position: absolute;
  inset: 0;
  display: flex;
  align-items: center;
  justify-content: center;
  text-align: center;
  font-weight: 300;
  letter-spacing: 0.14em;
  color: var(--color-text);
  white-space: nowrap;
}

.logo {
  font-size: 1rem;
}

/* ------------------------------------------------------------
   Desktop nav
   ------------------------------------------------------------ */
.main-nav {
  display: none;
  align-items: center;
  gap: var(--space-5);
}

.nav-links {
  display: flex;
  align-items: center;
  gap: var(--space-5);
}

.nav-links a {
  color: var(--color-text-muted);
  font-size: 0.95rem;
  font-weight: 500;
  transition: color var(--motion-fast) var(--ease-out);
}

.nav-links a:hover {
  color: var(--color-accent-hover);
}

.nav-cta {
  padding: 0.55rem 1.25rem;
}

/* ------------------------------------------------------------
   Hamburger
   ------------------------------------------------------------ */
.hamburger {
  display: inline-flex;
  flex-direction: column;
  justify-content: center;
  gap: 5px;
  width: 2.75rem;
  height: 2.75rem;
  padding: 0.6rem;
  border-radius: var(--radius-sm);
  border: 1px solid var(--color-border);
  background-color: var(--color-surface);
}

.hamburger-bar {
  display: block;
  width: 100%;
  height: 2px;
  border-radius: 2px;
  background-color: var(--color-text);
  transition: transform var(--motion-fast) var(--ease-out),
    opacity var(--motion-fast) var(--ease-out);
}

.hamburger.is-open .hamburger-bar:nth-child(1) {
  transform: translateY(7px) rotate(45deg);
}

.hamburger.is-open .hamburger-bar:nth-child(2) {
  opacity: 0;
}

.hamburger.is-open .hamburger-bar:nth-child(3) {
  transform: translateY(-7px) rotate(-45deg);
}

/* ------------------------------------------------------------
   Mobile nav overlay (slide-in panel)
   ------------------------------------------------------------ */
.mobile-nav {
  position: fixed;
  inset: 0;
  z-index: 99;
  display: flex;
  justify-content: flex-end;
}

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

.mobile-nav__backdrop {
  position: absolute;
  inset: 0;
  background-color: rgba(4, 6, 10, 0.6);
  backdrop-filter: blur(4px);
  -webkit-backdrop-filter: blur(4px);
  opacity: 0;
  transition: opacity var(--motion-med) var(--ease-out);
}

.mobile-nav.is-open .mobile-nav__backdrop {
  opacity: 1;
}

.mobile-nav__panel {
  position: relative;
  display: flex;
  flex-direction: column;
  gap: var(--space-6);
  width: min(20rem, 84vw);
  height: 100%;
  padding: calc(var(--header-height) + var(--space-5)) var(--space-6) var(--space-6);
  background-color: var(--color-bg-alt);
  border-left: 1px solid var(--color-border);
  box-shadow: var(--shadow-lift);
  transform: translateX(100%);
  transition: transform var(--motion-med) var(--ease-out);
}

.mobile-nav.is-open .mobile-nav__panel {
  transform: translateX(0);
}

.mobile-nav-links {
  display: flex;
  flex-direction: column;
  gap: var(--space-2);
}

.mobile-nav-links a {
  display: block;
  padding: var(--space-3) var(--space-2);
  font-size: 1.1rem;
  font-weight: 500;
  color: var(--color-text);
  border-radius: var(--radius-sm);
  transition: color var(--motion-fast) var(--ease-out),
    background-color var(--motion-fast) var(--ease-out);
}

.mobile-nav-links a:hover {
  color: var(--color-accent-hover);
  background-color: var(--color-accent-soft);
}

.mobile-nav__cta {
  margin-top: var(--space-3);
}

/* ------------------------------------------------------------
   Breakpoint: show desktop nav
   ------------------------------------------------------------ */
@media (min-width: 62rem) {
  .main-nav {
    display: flex;
  }

  .hamburger,
  .mobile-nav {
    display: none;
  }
}