/* AcidBase Mastery — Layout */

/* Nav */
.site-nav {
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  z-index: 100;
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 1.5rem var(--pad-x);
  background: rgba(13, 12, 10, 0.85);
  backdrop-filter: blur(12px);
  -webkit-backdrop-filter: blur(12px);
  border-bottom: 1px solid var(--divider);
  transition: transform 0.3s ease;
}

.site-nav.hidden {
  transform: translateY(-100%);
}

.nav-brand {
  font-family: var(--font-mono);
  font-size: 0.7rem;
  letter-spacing: 0.15em;
  text-transform: uppercase;
  color: var(--text);
  text-decoration: none;
  display: flex;
  align-items: center;
  gap: 0.5rem;
}

.nav-brand span {
  color: var(--teal);
}

.nav-links {
  display: flex;
  gap: 2rem;
  list-style: none;
}

.nav-links a {
  font-family: var(--font-mono);
  font-size: 0.65rem;
  letter-spacing: 0.15em;
  text-transform: uppercase;
  color: var(--text-dim);
  text-decoration: none;
  transition: color var(--transition);
  position: relative;
}

.nav-links a::after {
  content: '';
  position: absolute;
  bottom: -4px;
  left: 0;
  width: 100%;
  height: 1px;
  background: var(--teal);
  transform: scaleX(0);
  transform-origin: left;
  transition: transform 0.3s ease;
}

.nav-links a:hover,
.nav-links a:focus-visible,
.nav-links a.active {
  color: var(--text);
}

.nav-links a.active::after,
.nav-links a:hover::after,
.nav-links a:focus-visible::after {
  transform: scaleX(1);
}

.nav-user {
  display: flex;
  align-items: center;
  gap: 0.75rem;
}

.nav-user-photo {
  width: 28px;
  height: 28px;
  border-radius: 50%;
  border: 1px solid var(--surface-border);
}

.nav-user-name {
  font-family: var(--font-mono);
  font-size: 0.6rem;
  letter-spacing: 0.1em;
  color: var(--text-dim);
}

/* Mobile nav */
.nav-toggle {
  display: none;
  background: none;
  border: 1px solid var(--surface-border);
  color: var(--text);
  padding: 0.5rem;
  cursor: pointer;
  width: 36px;
  height: 36px;
  position: relative;
}

.nav-toggle span {
  display: block;
  width: 16px;
  height: 1px;
  background: var(--text);
  position: absolute;
  left: 50%;
  transform: translateX(-50%);
  transition: all 0.3s ease;
}

.nav-toggle span:nth-child(1) { top: 12px; }
.nav-toggle span:nth-child(2) { top: 17px; }
.nav-toggle span:nth-child(3) { top: 22px; }

.nav-toggle.open span:nth-child(1) {
  top: 17px;
  transform: translateX(-50%) rotate(45deg);
}

.nav-toggle.open span:nth-child(2) {
  opacity: 0;
}

.nav-toggle.open span:nth-child(3) {
  top: 17px;
  transform: translateX(-50%) rotate(-45deg);
}

/* Main content area */
#app {
  min-height: 100vh;
  padding-top: 70px;
}

.page {
  padding: 4rem var(--pad-x);
  max-width: 1400px;
  margin: 0 auto;
}

.page-header {
  margin-bottom: 4rem;
}

.page-title {
  font-size: clamp(2.5rem, 6vw, 5rem);
  font-weight: 300;
  letter-spacing: -0.02em;
  line-height: 1.1;
  margin-bottom: 1rem;
}

.page-title em {
  font-style: italic;
  color: var(--accent);
}

/* Footer */
.site-footer {
  padding: 3rem var(--pad-x);
  display: flex;
  justify-content: space-between;
  align-items: center;
  font-family: var(--font-mono);
  font-size: 0.6rem;
  letter-spacing: 0.1em;
  color: var(--text-dim);
  border-top: 1px solid var(--divider);
}

/* Responsive */
@media (max-width: 900px) {
  .nav-toggle {
    display: block;
  }

  .nav-links {
    position: fixed;
    top: 70px;
    left: 0;
    right: 0;
    background: rgba(13, 12, 10, 0.95);
    backdrop-filter: blur(12px);
    flex-direction: column;
    padding: 2rem var(--pad-x);
    gap: 1.5rem;
    border-bottom: 1px solid var(--divider);
    transform: translateY(-100%);
    opacity: 0;
    pointer-events: none;
    transition: all 0.3s ease;
  }

  .nav-links.open {
    transform: translateY(0);
    opacity: 1;
    pointer-events: all;
  }

  .nav-links a {
    font-size: 0.75rem;
  }

  .page {
    padding: 3rem 6vw;
  }
}

@media (max-width: 600px) {
  .site-footer {
    flex-direction: column;
    gap: 0.5rem;
    text-align: center;
  }
}