/* ==========================================================================
   Navigation
   ========================================================================== */

.nav {
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  z-index: var(--z-nav);
  padding: var(--space-3) var(--section-pad-x);
  display: flex;
  align-items: center;
  justify-content: space-between;
  transition: padding var(--dur-base) var(--ease-mastro),
              background-color var(--dur-base) var(--ease-mastro),
              border-color var(--dur-base) var(--ease-mastro),
              backdrop-filter var(--dur-base) var(--ease-mastro);
  border-bottom: 1px solid transparent;
}

.nav.is-scrolled {
  padding-block: var(--space-2);
  background: var(--glass-bg-on-dark);
  backdrop-filter: blur(var(--glass-blur-strong)) saturate(var(--glass-saturate));
  -webkit-backdrop-filter: blur(var(--glass-blur-strong)) saturate(var(--glass-saturate));
  border-bottom-color: var(--glass-border-on-dark);
  box-shadow: var(--glass-shadow-on-dark);
}

.nav__logo {
  display: flex;
  align-items: center;
  gap: var(--space-1);
}

.nav__logo img {
  height: 28px;
  width: auto;
}

.nav__logo-word {
  font-family: var(--font-display);
  font-weight: 700;
  font-size: 15px;
  letter-spacing: var(--ls-normal);
  color: var(--white);
}

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

.nav__link {
  position: relative;
  font-family: var(--font-display);
  font-size: 14px;
  font-weight: 500;
  color: rgba(255, 255, 255, 0.78);
  padding-block: 4px;
  transition: color var(--dur-fast) var(--ease-mastro);
}

.nav__link::after {
  content: '';
  position: absolute;
  left: 0;
  bottom: -2px;
  width: 100%;
  height: 1px;
  background: var(--mastro-flow);
  transform: scaleX(0);
  transform-origin: left;
  transition: transform var(--dur-base) var(--ease-mastro);
}

.nav__link:hover,
.nav__link:focus-visible,
.nav__link.is-active {
  color: var(--white);
}

.nav__link:hover::after,
.nav__link:focus-visible::after,
.nav__link.is-active::after {
  transform: scaleX(1);
}

.nav__right {
  display: flex;
  align-items: center;
  gap: var(--space-4);
}

.nav__cta {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  font-family: var(--font-display);
  font-size: 13px;
  font-weight: 600;
  color: var(--mastro-black);
  background: var(--glass-bg-bright);
  backdrop-filter: blur(var(--glass-blur)) saturate(var(--glass-saturate));
  -webkit-backdrop-filter: blur(var(--glass-blur)) saturate(var(--glass-saturate));
  border: 1px solid var(--glass-border-bright);
  box-shadow: var(--glass-shadow-bright);
  padding: 12px 20px;
  border-radius: var(--radius-full);
  white-space: nowrap;
}

.nav__cta svg {
  width: 14px;
  height: 14px;
  transition: transform var(--dur-fast) var(--ease-mastro);
}

.nav__cta:hover svg,
.nav__cta:focus-visible svg {
  transform: translateX(3px);
}

.nav__toggle {
  display: none;
  width: 40px;
  height: 40px;
  align-items: center;
  justify-content: center;
  border-radius: 50%;
  color: var(--white);
  background: var(--glass-bg-on-dark);
  backdrop-filter: blur(var(--glass-blur)) saturate(var(--glass-saturate));
  -webkit-backdrop-filter: blur(var(--glass-blur)) saturate(var(--glass-saturate));
  border: 1px solid var(--glass-border-on-dark);
}

.nav__toggle svg { width: 22px; height: 22px; }

.theme-toggle {
  position: relative;
  display: flex;
  align-items: center;
  justify-content: center;
  width: 38px;
  height: 38px;
  flex-shrink: 0;
  border-radius: 50%;
  border: 1px solid var(--glass-border-on-dark);
  background: var(--glass-bg-on-dark);
  backdrop-filter: blur(var(--glass-blur)) saturate(var(--glass-saturate));
  -webkit-backdrop-filter: blur(var(--glass-blur)) saturate(var(--glass-saturate));
  color: var(--white);
  transition: border-color var(--dur-fast) var(--ease-mastro), background-color var(--dur-fast) var(--ease-mastro);
}

.theme-toggle:hover,
.theme-toggle:focus-visible {
  border-color: rgba(255, 255, 255, 0.4);
  background: var(--glass-bg-on-dark-strong);
}

.theme-toggle__icon {
  position: absolute;
  width: 17px;
  height: 17px;
  opacity: 0;
  transform: rotate(-90deg) scale(0.5);
  transition: opacity var(--dur-base) var(--ease-mastro), transform var(--dur-base) var(--ease-mastro);
}

.theme-toggle__icon--moon {
  opacity: 1;
  transform: rotate(0deg) scale(1);
}

:root[data-theme="dark"] .theme-toggle__icon--moon {
  opacity: 0;
  transform: rotate(90deg) scale(0.5);
}

:root[data-theme="dark"] .theme-toggle__icon--sun {
  opacity: 1;
  transform: rotate(0deg) scale(1);
}

.nav__mobile {
  position: fixed;
  inset: 0;
  z-index: calc(var(--z-nav) - 1);
  background: var(--glass-bg-on-dark-strong);
  backdrop-filter: blur(var(--glass-blur-strong)) saturate(var(--glass-saturate));
  -webkit-backdrop-filter: blur(var(--glass-blur-strong)) saturate(var(--glass-saturate));
  display: flex;
  flex-direction: column;
  justify-content: center;
  padding: var(--space-8) var(--space-4);
  transform: translateY(-100%);
  visibility: hidden;
  transition: transform var(--dur-slow) var(--ease-mastro), visibility 0s linear var(--dur-slow);
}

.nav__mobile.is-open {
  transform: translateY(0);
  visibility: visible;
  transition: transform var(--dur-slow) var(--ease-mastro), visibility 0s linear 0s;
}

.nav__mobile-links {
  display: flex;
  flex-direction: column;
  gap: var(--space-2);
  margin-bottom: var(--space-6);
}

.nav__mobile-link {
  font-family: var(--font-display);
  font-size: clamp(32px, 9vw, 48px);
  font-weight: 600;
  color: var(--white);
  letter-spacing: var(--ls-tight);
}

.nav__mobile-cta {
  align-self: flex-start;
}

@media (max-width: 900px) {
  .nav__links { display: none; }
  .nav__toggle { display: flex; }
  .nav__right .nav__cta { display: none; }
}

body.no-scroll { overflow: hidden; }