/**
 * Modern Preloader CSS - Redesigned 2025
 * 
 * Purpose: Stunning, gradient-based preloader with progress bar
 * 
 * Features:
 * - Glass morphism design
 * - Gradient animations
 * - Particle effects
 * - Smooth transitions
 * - Fully responsive
 * - Accessibility focused
 */

/* ============================================
   CSS Variables - Modern Color Palette
   ============================================ */

:root {
  /* Gradient Theme (Based on #007A93) */
  --preloader-gradient-1: #005f73;
  --preloader-gradient-2: #007a93;
  --preloader-gradient-3: #0a9396;
  --preloader-gradient-4: #00b4d8;

  /* Common */
  --preloader-transition: 0.6s;
  --preloader-z-index: 999999;
}

/* ============================================
   Preloader Container
   ============================================ */

.preloader {
  position: fixed;
  top: 0;
  left: 0;
  width: 100%;
  height: 100%;
  display: flex;
  align-items: center;
  justify-content: center;
  z-index: var(--preloader-z-index);
  transition:
    opacity var(--preloader-transition) cubic-bezier(0.4, 0, 0.2, 1),
    visibility var(--preloader-transition) cubic-bezier(0.4, 0, 0.2, 1),
    transform var(--preloader-transition) cubic-bezier(0.4, 0, 0.2, 1);
  overflow: hidden;
  background: linear-gradient(
    135deg,
    var(--preloader-gradient-1) 0%,
    var(--preloader-gradient-2) 50%,
    var(--preloader-gradient-3) 100%
  );
  color: #ffffff;
  animation: gradientShift 8s ease infinite;
  background-size: 200% 200%;
}

@keyframes gradientShift {
  0%,
  100% {
    background-position: 0% 50%;
  }
  50% {
    background-position: 100% 50%;
  }
}

/* Hidden State with Scale Effect */
.preloader.preloader--hidden {
  opacity: 0;
  visibility: hidden;
  pointer-events: none;
  transform: scale(1.1);
}

/* ============================================
   Background Particles
   ============================================ */

.preloader__particles {
  position: absolute;
  width: 100%;
  height: 100%;
  overflow: hidden;
  opacity: 0.6;
}

.preloader__particle {
  position: absolute;
  background: currentColor;
  border-radius: 50%;
  animation: particleFloat 15s infinite ease-in-out;
}

.preloader__particle:nth-child(1) {
  width: 4px;
  height: 4px;
  left: 10%;
  animation-delay: 0s;
}
.preloader__particle:nth-child(2) {
  width: 6px;
  height: 6px;
  left: 20%;
  animation-delay: 1s;
}
.preloader__particle:nth-child(3) {
  width: 3px;
  height: 3px;
  left: 30%;
  animation-delay: 2s;
}
.preloader__particle:nth-child(4) {
  width: 5px;
  height: 5px;
  left: 40%;
  animation-delay: 3s;
}
.preloader__particle:nth-child(5) {
  width: 4px;
  height: 4px;
  left: 50%;
  animation-delay: 4s;
}
.preloader__particle:nth-child(6) {
  width: 6px;
  height: 6px;
  left: 60%;
  animation-delay: 5s;
}
.preloader__particle:nth-child(7) {
  width: 3px;
  height: 3px;
  left: 70%;
  animation-delay: 6s;
}
.preloader__particle:nth-child(8) {
  width: 5px;
  height: 5px;
  left: 80%;
  animation-delay: 7s;
}
.preloader__particle:nth-child(9) {
  width: 4px;
  height: 4px;
  left: 90%;
  animation-delay: 8s;
}
.preloader__particle:nth-child(10) {
  width: 6px;
  height: 6px;
  left: 15%;
  animation-delay: 9s;
}
.preloader__particle:nth-child(11) {
  width: 3px;
  height: 3px;
  left: 25%;
  animation-delay: 10s;
}
.preloader__particle:nth-child(12) {
  width: 5px;
  height: 5px;
  left: 35%;
  animation-delay: 11s;
}
.preloader__particle:nth-child(13) {
  width: 4px;
  height: 4px;
  left: 45%;
  animation-delay: 12s;
}
.preloader__particle:nth-child(14) {
  width: 6px;
  height: 6px;
  left: 55%;
  animation-delay: 13s;
}
.preloader__particle:nth-child(15) {
  width: 3px;
  height: 3px;
  left: 65%;
  animation-delay: 14s;
}
.preloader__particle:nth-child(16) {
  width: 5px;
  height: 5px;
  left: 75%;
  animation-delay: 0.5s;
}
.preloader__particle:nth-child(17) {
  width: 4px;
  height: 4px;
  left: 85%;
  animation-delay: 1.5s;
}
.preloader__particle:nth-child(18) {
  width: 6px;
  height: 6px;
  left: 95%;
  animation-delay: 2.5s;
}
.preloader__particle:nth-child(19) {
  width: 3px;
  height: 3px;
  left: 5%;
  animation-delay: 3.5s;
}
.preloader__particle:nth-child(20) {
  width: 5px;
  height: 5px;
  left: 12%;
  animation-delay: 4.5s;
}

@keyframes particleFloat {
  0%,
  100% {
    transform: translateY(100vh) translateX(0) rotate(0deg);
    opacity: 0;
  }
  10% {
    opacity: 0.6;
  }
  90% {
    opacity: 0.6;
  }
  100% {
    transform: translateY(-100vh) translateX(50px) rotate(360deg);
    opacity: 0;
  }
}

/* ============================================
   Main Content Container
   ============================================ */

.preloader__content {
  text-align: center;
  animation: contentFadeIn 0.8s cubic-bezier(0.4, 0, 0.2, 1);
  position: relative;
  z-index: 2;
}

@keyframes contentFadeIn {
  from {
    opacity: 0;
    transform: translateY(20px) scale(0.9);
  }
  to {
    opacity: 1;
    transform: translateY(0) scale(1);
  }
}

/* ============================================
   Logo Section
   ============================================ */

.preloader__logo-container {
  margin-bottom: 2.5rem;
}

.preloader__logo-wrapper {
  position: relative;
  display: inline-block;
  animation: logoFloat 3s ease-in-out infinite;
}

@keyframes logoFloat {
  0%,
  100% {
    transform: translateY(0px);
  }
  50% {
    transform: translateY(-10px);
  }
}

.preloader__logo-img {
  height: 80px;
  width: auto;
  max-width: 200px;
  border-radius: 12px;
  box-shadow: 0 10px 40px rgba(0, 0, 0, 0.2);
  position: relative;
  z-index: 2;
  filter: drop-shadow(0 0 20px rgba(0, 122, 147, 0.3));
}

/* Animated Rings Around Logo */
.preloader__logo-ring {
  position: absolute;
  top: 50%;
  left: 50%;
  width: 120px;
  height: 120px;
  border: 2px solid currentColor;
  border-radius: 50%;
  transform: translate(-50%, -50%);
  opacity: 0.3;
  animation: ringPulse 2s ease-out infinite;
}

.preloader__logo-ring--delayed {
  animation-delay: 1s;
}

@keyframes ringPulse {
  0% {
    transform: translate(-50%, -50%) scale(0.8);
    opacity: 0.5;
  }
  100% {
    transform: translate(-50%, -50%) scale(1.5);
    opacity: 0;
  }
}

/* ============================================
   Progress Bar Section (Glass Morphism)
   ============================================ */

.preloader__progress-wrapper {
  margin-top: 4.5rem;
  display: flex;
  flex-direction: column;
  align-items: center;
}

.preloader__glass-card {
  background: rgba(255, 255, 255, 0.15);
  backdrop-filter: blur(10px);
  -webkit-backdrop-filter: blur(10px);
  border: 1px solid rgba(255, 255, 255, 0.2);
  border-radius: 16px;
  padding: 1.5rem 2rem;
  min-width: 320px;
  max-width: 400px;
  box-shadow: 0 8px 32px rgba(0, 0, 0, 0.1);
}

/* Progress Track */
.preloader__progress-track {
  width: 100%;
  height: 8px;
  background: rgba(0, 0, 0, 0.1);
  border-radius: 100px;
  overflow: hidden;
  position: relative;
  margin-bottom: 1rem;
}

/* Progress Fill with Gradient */
.preloader__progress-fill {
  height: 100%;
  background: linear-gradient(90deg, var(--preloader-gradient-4) 0%, var(--preloader-gradient-3) 100%);
  border-radius: 100px;
  width: 0%;
  transition: width 0.3s cubic-bezier(0.4, 0, 0.2, 1);
  position: relative;
  overflow: hidden;
  box-shadow: 0 0 20px rgba(0, 180, 216, 0.5);
}

/* Glow Effect */
.preloader__progress-glow {
  position: absolute;
  top: 0;
  right: 0;
  bottom: 0;
  width: 40px;
  background: linear-gradient(90deg, transparent, rgba(255, 255, 255, 0.6));
  animation: progressGlow 1.5s ease-in-out infinite;
}

@keyframes progressGlow {
  0%,
  100% {
    opacity: 0.4;
  }
  50% {
    opacity: 1;
  }
}

/* Status Row */
.preloader__status-row {
  display: flex;
  justify-content: space-between;
  align-items: center;
  font-size: 0.875rem;
  font-weight: 500;
}

.preloader__status-text {
  margin: 0;
  opacity: 0.9;
  animation: statusPulse 2s ease-in-out infinite;
}

@keyframes statusPulse {
  0%,
  100% {
    opacity: 0.7;
  }
  50% {
    opacity: 1;
  }
}

.preloader__percentage {
  font-weight: 700;
  font-size: 1rem;
  color: currentColor;
  min-width: 40px;
  text-align: right;
  font-variant-numeric: tabular-nums;
}

/* ============================================
   Loading Dots
   ============================================ */

.preloader__dots {
  display: flex;
  gap: 8px;
  justify-content: center;
  margin-top: 1.5rem;
}

.preloader__dot {
  width: 10px;
  height: 10px;
  border-radius: 50%;
  background: currentColor;
  animation: dotBounce 1.4s ease-in-out infinite;
}

.preloader__dot:nth-child(1) {
  animation-delay: 0s;
}
.preloader__dot:nth-child(2) {
  animation-delay: 0.2s;
}
.preloader__dot:nth-child(3) {
  animation-delay: 0.4s;
}

@keyframes dotBounce {
  0%,
  60%,
  100% {
    transform: translateY(0) scale(1);
    opacity: 0.6;
  }
  30% {
    transform: translateY(-12px) scale(1.2);
    opacity: 1;
  }
}

/* ============================================
   Accessibility & Reduced Motion
   ============================================ */

@media (prefers-reduced-motion: reduce) {
  .preloader,
  .preloader__content,
  .preloader__logo-wrapper,
  .preloader__logo-ring,
  .preloader__dot,
  .preloader__particle,
  .preloader__progress-glow {
    animation: none !important;
  }

  .preloader {
    background: linear-gradient(135deg, var(--preloader-gradient-1) 0%, var(--preloader-gradient-2) 100%);
  }
}

/* ============================================
   Responsive Design
   ============================================ */

@media (max-width: 576px) {
  .preloader__glass-card {
    min-width: 280px;
    padding: 1.25rem 1.5rem;
  }

  .preloader__logo-img {
    height: 60px;
  }
}

/* ============================================
   Print & High Contrast
   ============================================ */

@media print {
  .preloader {
    display: none !important;
  }
}

@media (prefers-contrast: high) {
  .preloader {
    backdrop-filter: none;
    background: linear-gradient(135deg, var(--preloader-gradient-1) 0%, var(--preloader-gradient-2) 100%);
  }
}