/* ==========================================================================
   ALTUS — LAYOUT & ARCHITECTURE
   Asymmetry, Fixed Canvas/Video Background, Negative Space & HUD
   ========================================================================== */

/* Fixed Cinematic Backdrop */
.cinematic-backdrop {
  position: fixed;
  top: 0;
  left: 0;
  width: 100vw;
  height: 100vh;
  z-index: 0;
  overflow: hidden;
  pointer-events: none;
}

.backdrop-video {
  position: absolute;
  top: 50%;
  left: 50%;
  min-width: 100%;
  min-height: 100%;
  width: auto;
  height: auto;
  transform: translate(-50%, -50%) scale(1.02);
  object-fit: cover;
  opacity: 0;
  filter: contrast(1.15) brightness(0.95);
  transition: opacity 0.3s ease;
  will-change: transform, opacity;
}

/* Atmospheric Overlay: Radial Vignette & Grid Lines */
.backdrop-overlay {
  position: fixed;
  top: 0;
  left: 0;
  width: 100vw;
  height: 100vh;
  z-index: 1;
  pointer-events: none;
  background: 
    radial-gradient(circle at 50% 35%, rgba(5, 5, 7, 0.2) 0%, rgba(5, 5, 7, 0.7) 75%, #050507 100%),
    linear-gradient(180deg, rgba(5, 5, 7, 0.6) 0%, rgba(5, 5, 7, 0.2) 50%, rgba(5, 5, 7, 0.85) 100%);
}

.backdrop-grid {
  position: fixed;
  top: 0;
  left: 0;
  width: 100vw;
  height: 100vh;
  z-index: 1;
  pointer-events: none;
  background-size: 80px 80px;
  background-image: 
    linear-gradient(to right, rgba(255, 255, 255, 0.02) 1px, transparent 1px),
    linear-gradient(to bottom, rgba(255, 255, 255, 0.02) 1px, transparent 1px);
  opacity: 0.5;
}

/* Minimalist HUD Navigation */
.hud-header {
  position: fixed;
  top: 0;
  left: 0;
  width: 100%;
  padding: 1.75rem var(--container-padding);
  display: flex;
  justify-content: space-between;
  align-items: center;
  z-index: 100;
  mix-blend-mode: normal;
  pointer-events: none;
  transition: transform var(--transition-medium), background var(--transition-medium);
}

.hud-header.scrolled {
  background: rgba(5, 5, 7, 0.7);
  backdrop-filter: blur(16px);
  border-bottom: 1px solid rgba(255, 255, 255, 0.04);
}

.hud-brand {
  pointer-events: auto;
  display: flex;
  align-items: center;
  gap: 1.25rem;
}

.brand-symbol {
  font-family: var(--font-display);
  font-weight: 800;
  font-size: 1.4rem;
  letter-spacing: 0.15em;
  color: var(--text-primary);
  text-transform: uppercase;
}

.brand-status {
  font-family: var(--font-mono);
  font-size: 0.65rem;
  color: var(--text-tertiary);
  letter-spacing: 0.2em;
  text-transform: uppercase;
  display: flex;
  align-items: center;
  gap: 0.4rem;
}

.status-dot {
  width: 5px;
  height: 5px;
  border-radius: 50%;
  background-color: var(--accent-emerald);
  box-shadow: 0 0 8px var(--accent-emerald);
}

.hud-nav {
  pointer-events: auto;
  display: flex;
  align-items: center;
  gap: 2.25rem;
}

.nav-link {
  font-family: var(--font-heading);
  font-size: 0.85rem;
  font-weight: 400;
  color: var(--text-secondary);
  letter-spacing: 0.05em;
  position: relative;
  padding: 0.35rem 0;
  transition: color var(--transition-fast);
}

.nav-link::after {
  content: '';
  position: absolute;
  bottom: 0;
  left: 0;
  width: 0%;
  height: 1px;
  background-color: var(--text-primary);
  transition: width var(--transition-medium);
}

.nav-link:hover, .nav-link.active {
  color: var(--text-primary);
}

.nav-link:hover::after, .nav-link.active::after {
  width: 100%;
}

.hud-cta {
  pointer-events: auto;
  font-family: var(--font-mono);
  font-size: 0.8rem;
  text-transform: uppercase;
  letter-spacing: 0.12em;
  padding: 0.6rem 1.4rem;
  border: 1px solid var(--glass-border);
  background: var(--glass-bg-subtle);
  backdrop-filter: blur(12px);
  color: var(--text-primary);
  border-radius: 2px;
  transition: all var(--transition-fast);
}

.hud-cta:hover {
  background: rgba(255, 255, 255, 0.1);
  border-color: var(--text-primary);
  transform: translateY(-1px);
}

/* Floating Scroll Progress Indicator */
.hud-progress {
  position: fixed;
  right: 2.85rem;
  bottom: 6.8rem;
  z-index: 100;
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 0.75rem;
  pointer-events: none;
}

.progress-text {
  font-family: var(--font-mono);
  font-size: 0.7rem;
  letter-spacing: 0.15em;
  color: var(--text-tertiary);
}

.progress-bar-container {
  width: 1px;
  height: 60px;
  background: rgba(255, 255, 255, 0.1);
  position: relative;
  overflow: hidden;
}

.progress-bar-fill {
  position: absolute;
  top: 0;
  left: 0;
  width: 100%;
  height: 0%;
  background: var(--text-primary);
  box-shadow: 0 0 10px rgba(255, 255, 255, 0.8);
  transition: height 0.1s ease-out;
}

/* Page Frame / Container */
.page-container {
  position: relative;
  z-index: 2;
  width: 100%;
  max-width: var(--max-width);
  margin: 0 auto;
  padding: 0 var(--container-padding);
}

.section {
  position: relative;
  padding-top: var(--section-spacing);
  padding-bottom: var(--section-spacing);
  min-height: 80vh;
  display: flex;
  flex-direction: column;
  justify-content: center;
}

/* Layout Utilities */
.asymmetric-grid-2 {
  display: grid;
  grid-template-columns: 1.15fr 0.85fr;
  gap: clamp(2rem, 5vw, 6rem);
  align-items: center;
}

.asymmetric-grid-rev {
  display: grid;
  grid-template-columns: 0.85fr 1.15fr;
  gap: clamp(2rem, 5vw, 6rem);
  align-items: center;
}

/* Glass Surfaces */
.glass-panel {
  background: var(--glass-bg);
  backdrop-filter: var(--glass-blur);
  -webkit-backdrop-filter: var(--glass-blur);
  border: 1px solid var(--glass-border);
  box-shadow: var(--glass-shadow);
  border-radius: 4px;
  position: relative;
  overflow: hidden;
  transition: border-color var(--transition-medium), transform var(--transition-medium);
}

.glass-panel:hover {
  border-color: var(--glass-border-highlight);
}

/* Subtle Lighting Accent line inside panels */
.glass-panel::before {
  content: '';
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  height: 1px;
  background: linear-gradient(90deg, transparent, rgba(255, 255, 255, 0.25), transparent);
  pointer-events: none;
}