/* ICETT '26 Conference Website - Professional Stylesheet */
/* International Conference on Emerging Trends and Transformations in AI */

/* Import Google Fonts */
@import url("https://fonts.googleapis.com/css2?family=Space+Grotesk:wght@300;400;500;600;700&display=swap");
@import url("https://fonts.googleapis.com/css2?family=Inter:wght@300;400;500;600;700;800;900&display=swap");

/* Root Variables */
:root {
  --primary: #2563eb;
  --primary-dark: #1d4ed8;
  --primary-light: #3b82f6;
  --accent: #06b6d4;
  --accent-gradient: linear-gradient(135deg, #2563eb 0%, #06b6d4 100%);
  --background-light: #f8fafc;
  --background-dark: #0f172a;
  --surface-light: #ffffff;
  --surface-dark: #1e293b;
  --text-dark: #0f172a;
  --text-light: #f8fafc;
  --text-muted: #64748b;
  --border-light: #e2e8f0;
  --border-dark: #334155;
  --success: #10b981;
  --warning: #f59e0b;
  --error: #ef4444;

  /* Animation Timing */
  --ease-out-expo: cubic-bezier(0.16, 1, 0.3, 1);
  --ease-out-quart: cubic-bezier(0.25, 1, 0.5, 1);
  --ease-in-out-quart: cubic-bezier(0.76, 0, 0.24, 1);
  --spring: cubic-bezier(0.34, 1.56, 0.64, 1);
}

/* Base Styles */
* {
  margin: 0;
  padding: 0;
  box-sizing: border-box;
}

html {
  scroll-behavior: smooth;
}

body {
  font-family:
    "Inter",
    "Space Grotesk",
    -apple-system,
    BlinkMacSystemFont,
    sans-serif;
  line-height: 1.6;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
}

/* Font Display Class */
.font-display {
  font-family: "Space Grotesk", "Inter", sans-serif;
}

/* ============================================
   SCROLL-TRIGGERED ANIMATIONS
   ============================================ */

/* Elements waiting to be revealed */
.reveal {
  opacity: 0;
  transform: translateY(60px);
  transition: all 0.8s var(--ease-out-expo);
}

.reveal.active {
  opacity: 1;
  transform: translateY(0);
}

/* Reveal from different directions */
.reveal-left {
  opacity: 0;
  transform: translateX(-60px);
  transition: all 0.8s var(--ease-out-expo);
}

.reveal-left.active {
  opacity: 1;
  transform: translateX(0);
}

.reveal-right {
  opacity: 0;
  transform: translateX(60px);
  transition: all 0.8s var(--ease-out-expo);
}

.reveal-right.active {
  opacity: 1;
  transform: translateX(0);
}

.reveal-scale {
  opacity: 0;
  transform: scale(0.8);
  transition: all 0.8s var(--ease-out-expo);
}

.reveal-scale.active {
  opacity: 1;
  transform: scale(1);
}

/* Staggered children animation */
.stagger-children > * {
  opacity: 0;
  transform: translateY(30px);
  transition: all 0.6s var(--ease-out-expo);
}

.stagger-children.active > *:nth-child(1) {
  transition-delay: 0.1s;
  opacity: 1;
  transform: translateY(0);
}
.stagger-children.active > *:nth-child(2) {
  transition-delay: 0.2s;
  opacity: 1;
  transform: translateY(0);
}
.stagger-children.active > *:nth-child(3) {
  transition-delay: 0.3s;
  opacity: 1;
  transform: translateY(0);
}
.stagger-children.active > *:nth-child(4) {
  transition-delay: 0.4s;
  opacity: 1;
  transform: translateY(0);
}
.stagger-children.active > *:nth-child(5) {
  transition-delay: 0.5s;
  opacity: 1;
  transform: translateY(0);
}
.stagger-children.active > *:nth-child(6) {
  transition-delay: 0.6s;
  opacity: 1;
  transform: translateY(0);
}

/* ============================================
   KEYFRAME ANIMATIONS
   ============================================ */

/* Fade In Up */
@keyframes fadeInUp {
  from {
    opacity: 0;
    transform: translateY(40px);
  }
  to {
    opacity: 1;
    transform: translateY(0);
  }
}

.animate-fade-in-up {
  animation: fadeInUp 0.8s var(--ease-out-expo) forwards;
}

/* Fade In Down */
@keyframes fadeInDown {
  from {
    opacity: 0;
    transform: translateY(-40px);
  }
  to {
    opacity: 1;
    transform: translateY(0);
  }
}

.animate-fade-in-down {
  animation: fadeInDown 0.8s var(--ease-out-expo) forwards;
}

/* Fade In Left */
@keyframes fadeInLeft {
  from {
    opacity: 0;
    transform: translateX(-40px);
  }
  to {
    opacity: 1;
    transform: translateX(0);
  }
}

.animate-fade-in-left {
  animation: fadeInLeft 0.8s var(--ease-out-expo) forwards;
}

/* Fade In Right */
@keyframes fadeInRight {
  from {
    opacity: 0;
    transform: translateX(40px);
  }
  to {
    opacity: 1;
    transform: translateX(0);
  }
}

.animate-fade-in-right {
  animation: fadeInRight 0.8s var(--ease-out-expo) forwards;
}

/* Scale In */
@keyframes scaleIn {
  from {
    opacity: 0;
    transform: scale(0.9);
  }
  to {
    opacity: 1;
    transform: scale(1);
  }
}

.animate-scale-in {
  animation: scaleIn 0.6s var(--ease-out-expo) forwards;
}

/* Bounce In */
@keyframes bounceIn {
  0% {
    opacity: 0;
    transform: scale(0.3);
  }
  50% {
    transform: scale(1.05);
  }
  70% {
    transform: scale(0.9);
  }
  100% {
    opacity: 1;
    transform: scale(1);
  }
}

.animate-bounce-in {
  animation: bounceIn 0.8s var(--spring) forwards;
}

/* Float Animation */
@keyframes float {
  0%,
  100% {
    transform: translateY(0);
  }
  50% {
    transform: translateY(-20px);
  }
}

.animate-float {
  animation: float 6s ease-in-out infinite;
}

/* Pulse Glow */
@keyframes pulseGlow {
  0%,
  100% {
    box-shadow: 0 0 20px rgba(37, 99, 235, 0.3);
  }
  50% {
    box-shadow: 0 0 40px rgba(37, 99, 235, 0.6);
  }
}

.animate-pulse-glow {
  animation: pulseGlow 2s ease-in-out infinite;
}

/* Shimmer Effect */
@keyframes shimmer {
  0% {
    background-position: -200% 0;
  }
  100% {
    background-position: 200% 0;
  }
}

.animate-shimmer {
  background: linear-gradient(
    90deg,
    transparent 0%,
    rgba(255, 255, 255, 0.4) 50%,
    transparent 100%
  );
  background-size: 200% 100%;
  animation: shimmer 2s infinite;
}

/* Gradient Flow */
@keyframes gradientFlow {
  0% {
    background-position: 0% 50%;
  }
  50% {
    background-position: 100% 50%;
  }
  100% {
    background-position: 0% 50%;
  }
}

.animate-gradient {
  background-size: 200% 200%;
  animation: gradientFlow 8s ease infinite;
}

/* Spin Slow */
@keyframes spinSlow {
  from {
    transform: rotate(0deg);
  }
  to {
    transform: rotate(360deg);
  }
}

.animate-spin-slow {
  animation: spinSlow 20s linear infinite;
}

/* Text Reveal */
@keyframes textReveal {
  0% {
    clip-path: polygon(0 0, 0 0, 0 100%, 0 100%);
  }
  100% {
    clip-path: polygon(0 0, 100% 0, 100% 100%, 0 100%);
  }
}

.animate-text-reveal {
  animation: textReveal 1s var(--ease-out-expo) forwards;
}

/* Counter Number Animation */
@keyframes countUp {
  from {
    opacity: 0;
    transform: translateY(20px);
  }
  to {
    opacity: 1;
    transform: translateY(0);
  }
}

.animate-count {
  animation: countUp 0.5s var(--ease-out-expo) forwards;
}

/* ============================================
   HERO SECTION PARTICLES/BACKGROUND
   ============================================ */

.hero-bg {
  position: relative;
  overflow: hidden;
}

.hero-bg::before {
  content: "";
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  bottom: 0;
  background:
    radial-gradient(
      circle at 20% 80%,
      rgba(37, 99, 235, 0.15) 0%,
      transparent 50%
    ),
    radial-gradient(
      circle at 80% 20%,
      rgba(6, 182, 212, 0.15) 0%,
      transparent 50%
    ),
    radial-gradient(
      circle at 50% 50%,
      rgba(37, 99, 235, 0.05) 0%,
      transparent 70%
    );
  pointer-events: none;
}

/* Animated Grid Background */
.grid-bg {
  background-image:
    linear-gradient(rgba(37, 99, 235, 0.03) 1px, transparent 1px),
    linear-gradient(90deg, rgba(37, 99, 235, 0.03) 1px, transparent 1px);
  background-size: 50px 50px;
  animation: gridMove 20s linear infinite;
}

@keyframes gridMove {
  0% {
    background-position: 0 0;
  }
  100% {
    background-position: 50px 50px;
  }
}

/* ============================================
   BUTTON ANIMATIONS
   ============================================ */

.btn-primary {
  position: relative;
  overflow: hidden;
  transition: all 0.3s var(--ease-out-quart);
}

.btn-primary::before {
  content: "";
  position: absolute;
  top: 0;
  left: -100%;
  width: 100%;
  height: 100%;
  background: linear-gradient(
    90deg,
    transparent,
    rgba(255, 255, 255, 0.2),
    transparent
  );
  transition: left 0.5s var(--ease-out-quart);
}

.btn-primary:hover::before {
  left: 100%;
}

.btn-primary:hover {
  transform: translateY(-2px);
  box-shadow: 0 10px 40px -10px rgba(37, 99, 235, 0.5);
}

.btn-primary:active {
  transform: translateY(0);
}

/* Ripple Effect */
.btn-ripple {
  position: relative;
  overflow: hidden;
}

.btn-ripple .ripple {
  position: absolute;
  border-radius: 50%;
  background: rgba(255, 255, 255, 0.4);
  transform: scale(0);
  animation: rippleEffect 0.6s linear;
  pointer-events: none;
}

@keyframes rippleEffect {
  to {
    transform: scale(4);
    opacity: 0;
  }
}

/* ============================================
   CARD ANIMATIONS
   ============================================ */

.card-hover {
  transition: all 0.4s var(--ease-out-expo);
}

.card-hover:hover {
  transform: translateY(-8px);
  box-shadow: 0 25px 50px -12px rgba(0, 0, 0, 0.15);
}

.card-hover::after {
  content: "";
  position: absolute;
  inset: 0;
  border-radius: inherit;
  opacity: 0;
  transition: opacity 0.4s var(--ease-out-expo);
  background: linear-gradient(
    135deg,
    rgba(37, 99, 235, 0.1) 0%,
    transparent 60%
  );
  pointer-events: none;
}

.card-hover:hover::after {
  opacity: 1;
}

/* Card Tilt Effect */
.card-tilt {
  transform-style: preserve-3d;
  transition: transform 0.3s var(--ease-out-quart);
}

/* ============================================
   NAVIGATION ANIMATIONS
   ============================================ */

.nav-link {
  position: relative;
  transition: color 0.3s ease;
}

.nav-link::after {
  content: "";
  position: absolute;
  bottom: -4px;
  left: 0;
  width: 0;
  height: 2px;
  background: var(--primary);
  transition: width 0.3s var(--ease-out-expo);
}

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

/* Mobile Menu Animation */
.mobile-menu {
  transform: translateX(100%);
  transition: transform 0.4s var(--ease-out-expo);
}

.mobile-menu.open {
  transform: translateX(0);
}

/* Hamburger Animation */
.hamburger {
  display: flex;
  flex-direction: column;
  gap: 6px;
  cursor: pointer;
}

.hamburger span {
  display: block;
  width: 24px;
  height: 2px;
  background: currentColor;
  transition: all 0.3s var(--ease-out-quart);
  transform-origin: center;
}

.hamburger.active span:nth-child(1) {
  transform: rotate(45deg) translate(6px, 6px);
}

.hamburger.active span:nth-child(2) {
  opacity: 0;
  transform: scaleX(0);
}

.hamburger.active span:nth-child(3) {
  transform: rotate(-45deg) translate(6px, -6px);
}

/* ============================================
   COUNTDOWN TIMER ANIMATIONS
   ============================================ */

.countdown-box {
  transition: all 0.3s var(--ease-out-quart);
}

.countdown-box:hover {
  transform: scale(1.05);
}

.countdown-number {
  transition: all 0.3s var(--ease-out-expo);
}

.countdown-number.flip {
  animation: flipNumber 0.5s var(--ease-out-expo);
}

@keyframes flipNumber {
  0% {
    transform: rotateX(0);
  }
  50% {
    transform: rotateX(-90deg);
    opacity: 0;
  }
  51% {
    transform: rotateX(90deg);
  }
  100% {
    transform: rotateX(0);
    opacity: 1;
  }
}

/* ============================================
   LOADING ANIMATIONS
   ============================================ */

/* Page Loader */
.page-loader {
  position: fixed;
  inset: 0;
  background: var(--background-light);
  display: flex;
  align-items: center;
  justify-content: center;
  z-index: 9999;
  transition:
    opacity 0.5s ease,
    visibility 0.5s ease;
}

.page-loader.hidden {
  opacity: 0;
  visibility: hidden;
}

.loader-spinner {
  width: 50px;
  height: 50px;
  border: 3px solid var(--border-light);
  border-top-color: var(--primary);
  border-radius: 50%;
  animation: spin 1s linear infinite;
}

@keyframes spin {
  to {
    transform: rotate(360deg);
  }
}

/* Skeleton Loading */
.skeleton {
  background: linear-gradient(90deg, #f0f0f0 25%, #e0e0e0 50%, #f0f0f0 75%);
  background-size: 200% 100%;
  animation: skeletonShimmer 1.5s infinite;
}

@keyframes skeletonShimmer {
  0% {
    background-position: -200% 0;
  }
  100% {
    background-position: 200% 0;
  }
}

/* ============================================
   SCROLL PROGRESS INDICATOR
   ============================================ */

.scroll-progress {
  position: fixed;
  top: 0;
  left: 0;
  width: 0%;
  height: 3px;
  background: var(--accent-gradient);
  z-index: 9999;
  transition: width 0.1s linear;
}

/* ============================================
   PARALLAX EFFECTS
   ============================================ */

.parallax {
  will-change: transform;
}

.parallax-slow {
  transform: translateY(calc(var(--scroll) * 0.3));
}

.parallax-medium {
  transform: translateY(calc(var(--scroll) * 0.5));
}

.parallax-fast {
  transform: translateY(calc(var(--scroll) * 0.7));
}

/* ============================================
   DARK MODE STYLES
   ============================================ */

.dark {
  color-scheme: dark;
}

.dark .page-loader {
  background: var(--background-dark);
}

.dark .skeleton {
  background: linear-gradient(90deg, #1e293b 25%, #334155 50%, #1e293b 75%);
  background-size: 200% 100%;
}

/* ============================================
   CURSOR EFFECTS
   ============================================ */

.cursor-glow {
  position: fixed;
  width: 300px;
  height: 300px;
  border-radius: 50%;
  background: radial-gradient(
    circle,
    rgba(37, 99, 235, 0.15) 0%,
    transparent 70%
  );
  pointer-events: none;
  transform: translate(-50%, -50%);
  z-index: 0;
  opacity: 0;
  transition: opacity 0.3s ease;
}

.cursor-glow.active {
  opacity: 1;
}

/* ============================================
   CUSTOM SCROLLBAR
   ============================================ */

::-webkit-scrollbar {
  width: 10px;
}

::-webkit-scrollbar-track {
  background: var(--background-light);
}

.dark ::-webkit-scrollbar-track {
  background: var(--background-dark);
}

::-webkit-scrollbar-thumb {
  background: linear-gradient(180deg, var(--primary) 0%, var(--accent) 100%);
  border-radius: 5px;
}

::-webkit-scrollbar-thumb:hover {
  background: linear-gradient(
    180deg,
    var(--primary-dark) 0%,
    var(--primary) 100%
  );
}

/* ============================================
   SPECIAL EFFECTS
   ============================================ */

/* Glassmorphism */
.glass {
  background: rgba(255, 255, 255, 0.1);
  backdrop-filter: blur(20px);
  -webkit-backdrop-filter: blur(20px);
  border: 1px solid rgba(255, 255, 255, 0.2);
}

.dark .glass {
  background: rgba(0, 0, 0, 0.2);
  border: 1px solid rgba(255, 255, 255, 0.1);
}

/* Neon Glow */
.neon-text {
  text-shadow:
    0 0 10px rgba(37, 99, 235, 0.5),
    0 0 20px rgba(37, 99, 235, 0.3),
    0 0 40px rgba(37, 99, 235, 0.2);
}

.neon-box {
  box-shadow:
    0 0 20px rgba(37, 99, 235, 0.3),
    inset 0 0 20px rgba(37, 99, 235, 0.1);
}

/* Gradient Text */
.gradient-text {
  background: var(--accent-gradient);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
}

/* ============================================
   TOOLTIP ANIMATIONS
   ============================================ */

.tooltip {
  position: relative;
}

.tooltip::after {
  content: attr(data-tooltip);
  position: absolute;
  bottom: 100%;
  left: 50%;
  transform: translateX(-50%) translateY(10px);
  padding: 8px 12px;
  background: var(--background-dark);
  color: var(--text-light);
  font-size: 12px;
  border-radius: 6px;
  white-space: nowrap;
  opacity: 0;
  visibility: hidden;
  transition: all 0.3s var(--ease-out-quart);
  pointer-events: none;
}

.tooltip:hover::after {
  opacity: 1;
  visibility: visible;
  transform: translateX(-50%) translateY(-5px);
}

/* ============================================
   MEDIA QUERIES FOR REDUCED MOTION
   ============================================ */

@media (prefers-reduced-motion: reduce) {
  *,
  *::before,
  *::after {
    animation-duration: 0.01ms !important;
    animation-iteration-count: 1 !important;
    transition-duration: 0.01ms !important;
  }

  .reveal,
  .reveal-left,
  .reveal-right,
  .reveal-scale {
    opacity: 1;
    transform: none;
  }
}

/* ============================================
   UTILITY ANIMATION DELAYS
   ============================================ */

.delay-100 {
  animation-delay: 0.1s;
}
.delay-200 {
  animation-delay: 0.2s;
}
.delay-300 {
  animation-delay: 0.3s;
}
.delay-400 {
  animation-delay: 0.4s;
}
.delay-500 {
  animation-delay: 0.5s;
}
.delay-600 {
  animation-delay: 0.6s;
}
.delay-700 {
  animation-delay: 0.7s;
}
.delay-800 {
  animation-delay: 0.8s;
}
.delay-900 {
  animation-delay: 0.9s;
}
.delay-1000 {
  animation-delay: 1s;
}

.reveal-visible {
  opacity: 1 !important;
  transform: translateY(0) !important;
}