/* Loading Screen — Retro 90s/2000s Nostalgia */

.loading-screen {
  position: fixed;
  inset: 0;
  z-index: var(--z-loading);
  background: var(--color-black);
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  overflow: hidden;
  cursor: default;
}

/* CRT scanline effect */
.loading-screen::before {
  content: '';
  position: absolute;
  inset: 0;
  background: repeating-linear-gradient(
    0deg,
    transparent,
    transparent 2px,
    rgba(0, 0, 0, 0.15) 2px,
    rgba(0, 0, 0, 0.15) 4px
  );
  pointer-events: none;
  z-index: 2;
}

/* CRT flicker */
.loading-screen::after {
  content: '';
  position: absolute;
  inset: 0;
  background: rgba(245, 242, 237, 0.02);
  pointer-events: none;
  z-index: 3;
  animation: crt-flicker 0.1s infinite;
}

@keyframes crt-flicker {
  0%   { opacity: 0.02; }
  50%  { opacity: 0.04; }
  100% { opacity: 0.02; }
}

/* Title assembling letter by letter */
.loading-title {
  font-family: var(--font-display);
  font-size: clamp(2.5rem, 6vw, 5rem);
  color: var(--color-paper);
  text-transform: uppercase;
  letter-spacing: 0.3em;
  position: relative;
  z-index: 4;
  overflow: hidden;
}

.loading-title .letter {
  display: inline-block;
  opacity: 0;
  transform: translateY(20px);
  animation: letter-appear 0.4s var(--ease-out) forwards;
}

@keyframes letter-appear {
  to {
    opacity: 1;
    transform: translateY(0);
  }
}

/* Retro progress bar */
.loading-bar-container {
  margin-top: var(--space-lg);
  width: min(400px, 80vw);
  position: relative;
  z-index: 4;
}

.loading-bar-track {
  width: 100%;
  height: 20px;
  border: 2px solid var(--gray-600);
  background: var(--gray-900);
  position: relative;
  /* Pixelated look */
  image-rendering: pixelated;
}

.loading-bar-fill {
  height: 100%;
  background: var(--color-accent);
  width: 0%;
  transition: width 0.3s steps(20);
  position: relative;
}

/* Chunky pixel segments */
.loading-bar-fill::after {
  content: '';
  position: absolute;
  inset: 0;
  background: repeating-linear-gradient(
    90deg,
    transparent,
    transparent 18px,
    rgba(0, 0, 0, 0.3) 18px,
    rgba(0, 0, 0, 0.3) 20px
  );
}

.loading-percentage {
  font-family: var(--font-mono);
  font-size: var(--text-caption);
  color: var(--gray-400);
  text-align: right;
  margin-top: var(--space-xs);
}

/* Loading messages */
.loading-message {
  font-family: var(--font-mono);
  font-size: var(--text-small);
  color: var(--gray-500);
  margin-top: var(--space-md);
  position: relative;
  z-index: 4;
  min-height: 1.5em;
}

.loading-message::after {
  content: '_';
  animation: blink-cursor 0.6s step-end infinite;
}

@keyframes blink-cursor {
  50% { opacity: 0; }
}

/* Click to enter prompt */
.loading-enter {
  position: relative;
  z-index: 4;
  margin-top: var(--space-xl);
  opacity: 0;
  transition: opacity 0.5s ease;
}

.loading-enter.visible {
  opacity: 1;
}

.loading-enter button {
  font-family: var(--font-secondary);
  font-size: var(--text-small);
  font-weight: 600;
  letter-spacing: 0.3em;
  text-transform: uppercase;
  color: var(--color-paper);
  border: 1px solid var(--gray-600);
  padding: 0.75em 2em;
  cursor: pointer;
  transition: all var(--duration-normal) ease;
}

.loading-enter button:hover {
  background: var(--color-paper);
  color: var(--color-black);
  border-color: var(--color-paper);
}

/* Exit animation — curtain split */
.loading-screen.exit {
  animation: none;
}

.loading-screen.exit .loading-curtain-left,
.loading-screen.exit .loading-curtain-right {
  position: absolute;
  top: 0;
  width: 50%;
  height: 100%;
  background: var(--color-black);
  z-index: 10;
}

.loading-screen.exit .loading-curtain-left {
  left: 0;
  animation: curtain-left 0.8s var(--ease-in-out) forwards;
}

.loading-screen.exit .loading-curtain-right {
  right: 0;
  animation: curtain-right 0.8s var(--ease-in-out) forwards;
}

@keyframes curtain-left {
  to { transform: translateX(-100%); }
}

@keyframes curtain-right {
  to { transform: translateX(100%); }
}

.loading-screen.exit .loading-title,
.loading-screen.exit .loading-bar-container,
.loading-screen.exit .loading-message,
.loading-screen.exit .loading-enter {
  animation: fade-out 0.3s ease forwards;
}

@keyframes fade-out {
  to { opacity: 0; }
}

/* Hidden after exit */
.loading-screen.hidden {
  display: none;
}

/* Mobile */
@media (max-width: 768px) {
  .loading-title {
    font-size: clamp(1.75rem, 8vw, 2.5rem);
    letter-spacing: 0.15em;
  }

  .loading-bar-container {
    width: min(300px, 85vw);
  }

  .loading-bar-track {
    height: 16px;
  }

  .loading-message {
    font-size: var(--text-caption);
    padding-inline: var(--space-sm);
    text-align: center;
  }

  .loading-enter {
    margin-top: var(--space-lg);
  }

  .loading-enter button {
    font-size: var(--text-caption);
    letter-spacing: 0.2em;
    padding: 0.65em 1.5em;
  }
}