/* ===================================
   EnglishPlaytime - Kids Learning CSS
   =================================== */

/* ===== IMPORTS ===== */
@import url('https://fonts.googleapis.com/css2?family=Fredoka:wght@300;400;500;600;700&family=Bubblegum+Sans&display=swap');

/* ===== CSS VARIABLES ===== */
:root {
  /* Primary Colors - Vibrant & Playful */
  --color-primary: #FF6B6B;
  --color-secondary: #4ECDC4;
  --color-accent: #FFE66D;
  --color-success: #95E1D3;
  --color-purple: #AB47BC;
  --color-orange: #FF9800;
  --color-pink: #FF4081;
  --color-blue: #42A5F5;
  
  /* Gradients */
  --gradient-rainbow: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
  --gradient-sunset: linear-gradient(135deg, #f093fb 0%, #f5576c 100%);
  --gradient-ocean: linear-gradient(135deg, #4facfe 0%, #00f2fe 100%);
  --gradient-candy: linear-gradient(135deg, #fa709a 0%, #fee140 100%);
  --gradient-mint: linear-gradient(135deg, #30cfd0 0%, #330867 100%);
  
  /* Neutral Colors */
  --color-bg: #FFF9F0;
  --color-white: #FFFFFF;
  --color-dark: #2D3436;
  --color-gray: #636e72;
  --color-light-gray: #dfe6e9;
  
  /* Typography */
  --font-primary: 'Fredoka', sans-serif;
  --font-display: 'Bubblegum Sans', cursive;
  
  /* Spacing */
  --spacing-xs: 0.5rem;
  --spacing-sm: 1rem;
  --spacing-md: 1.5rem;
  --spacing-lg: 2rem;
  --spacing-xl: 3rem;
  --spacing-xxl: 4rem;
  
  /* Border Radius */
  --radius-sm: 8px;
  --radius-md: 16px;
  --radius-lg: 24px;
  --radius-xl: 32px;
  --radius-round: 50%;
  
  /* Shadows */
  --shadow-sm: 0 2px 8px rgba(0,0,0,0.1);
  --shadow-md: 0 4px 16px rgba(0,0,0,0.15);
  --shadow-lg: 0 8px 32px rgba(0,0,0,0.2);
  --shadow-colorful: 0 8px 32px rgba(255, 107, 107, 0.3);
  
  /* Animations */
  --transition-fast: 0.2s ease;
  --transition-normal: 0.3s ease;
  --transition-slow: 0.5s ease;
}

/* ===== RESET & BASE STYLES ===== */
* {
  margin: 0;
  padding: 0;
  box-sizing: border-box;
}

html {
  font-size: 16px;
  scroll-behavior: smooth;
}

body {
  font-family: var(--font-primary);
  background: var(--color-bg);
  color: var(--color-dark);
  line-height: 1.6;
  overflow-x: hidden;
}

/* ===== ANIMATED BACKGROUND ===== */
body::before {
  content: '';
  position: fixed;
  top: 0;
  left: 0;
  width: 100%;
  height: 100%;
  background: 
    radial-gradient(circle at 20% 50%, rgba(255, 107, 107, 0.1) 0%, transparent 50%),
    radial-gradient(circle at 80% 80%, rgba(78, 205, 196, 0.1) 0%, transparent 50%),
    radial-gradient(circle at 40% 20%, rgba(255, 230, 109, 0.1) 0%, transparent 50%);
  z-index: -1;
  animation: backgroundShift 20s ease infinite;
}

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

/* ===== TYPOGRAPHY ===== */
h1, h2, h3, h4, h5, h6 {
  font-family: var(--font-display);
  font-weight: 700;
  line-height: 1.2;
  color: var(--color-dark);
}

h1 {
  font-size: 3rem;
  margin-bottom: var(--spacing-md);
}

h2 {
  font-size: 2.5rem;
  margin-bottom: var(--spacing-md);
}

h3 {
  font-size: 2rem;
  margin-bottom: var(--spacing-sm);
}

p {
  margin-bottom: var(--spacing-sm);
  font-size: 1.1rem;
}

/* ===== LAYOUT ===== */
.container {
  max-width: 1200px;
  margin: 0 auto;
  padding: 0 var(--spacing-md);
}

.section {
  padding: var(--spacing-xl) 0;
  min-height: 100vh;
}

/* ===== HEADER ===== */
.header {
  background: var(--color-white);
  padding: var(--spacing-md) 0;
  box-shadow: var(--shadow-sm);
  position: sticky;
  top: 0;
  z-index: 100;
  animation: slideDown 0.5s ease;
}

@keyframes slideDown {
  from {
    transform: translateY(-100%);
    opacity: 0;
  }
  to {
    transform: translateY(0);
    opacity: 1;
  }
}

.header-content {
  display: flex;
  justify-content: space-between;
  align-items: center;
  flex-wrap: wrap;
  gap: var(--spacing-md);
}

.logo {
  display: flex;
  align-items: center;
  gap: var(--spacing-sm);
  text-decoration: none;
  color: var(--color-dark);
}

.logo-img {
  height: 60px;
  width: auto;
  animation: bounce 2s ease infinite;
}

.logo-text {
  font-family: var(--font-display);
  font-size: 2rem;
  background: var(--gradient-rainbow);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
}

/* ===== NAVIGATION ===== */
.nav {
  display: flex;
  gap: var(--spacing-sm);
  flex-wrap: wrap;
}

.nav-link {
  padding: var(--spacing-xs) var(--spacing-md);
  border-radius: var(--radius-lg);
  text-decoration: none;
  font-weight: 600;
  font-size: 1.1rem;
  transition: all var(--transition-normal);
  position: relative;
  overflow: hidden;
}

.nav-link::before {
  content: '';
  position: absolute;
  top: 0;
  left: -100%;
  width: 100%;
  height: 100%;
  background: var(--gradient-rainbow);
  transition: left var(--transition-normal);
  z-index: -1;
}

.nav-link:hover::before {
  left: 0;
}

.nav-link:hover {
  color: var(--color-white);
  transform: translateY(-2px);
  box-shadow: var(--shadow-md);
}

.nav-link.home { background: var(--gradient-rainbow); color: white; }
.nav-link.songs { background: var(--gradient-sunset); color: white; }
.nav-link.vocab { background: var(--gradient-ocean); color: white; }
.nav-link.games { background: var(--gradient-candy); color: white; }
.nav-link.topics { background: var(--gradient-mint); color: white; }

/* ===== BUTTONS ===== */
.btn {
  padding: var(--spacing-sm) var(--spacing-lg);
  border: none;
  border-radius: var(--radius-lg);
  font-family: var(--font-primary);
  font-weight: 600;
  font-size: 1.1rem;
  cursor: pointer;
  transition: all var(--transition-normal);
  text-decoration: none;
  display: inline-block;
  text-align: center;
  position: relative;
  overflow: hidden;
}

.btn::after {
  content: '';
  position: absolute;
  top: 50%;
  left: 50%;
  width: 0;
  height: 0;
  border-radius: 50%;
  background: rgba(255, 255, 255, 0.5);
  transform: translate(-50%, -50%);
  transition: width 0.6s, height 0.6s;
}

.btn:hover::after {
  width: 300px;
  height: 300px;
}

.btn:hover {
  transform: translateY(-3px) scale(1.05);
  box-shadow: var(--shadow-lg);
}

.btn:active {
  transform: translateY(-1px) scale(1.02);
}

.btn-primary {
  background: var(--gradient-rainbow);
  color: var(--color-white);
}

.btn-secondary {
  background: var(--gradient-sunset);
  color: var(--color-white);
}

.btn-success {
  background: var(--gradient-ocean);
  color: var(--color-white);
}

.btn-lg {
  padding: var(--spacing-md) var(--spacing-xl);
  font-size: 1.3rem;
}

/* ===== CARDS ===== */
.card {
  background: var(--color-white);
  border-radius: var(--radius-lg);
  padding: var(--spacing-lg);
  box-shadow: var(--shadow-md);
  transition: all var(--transition-normal);
  position: relative;
  overflow: hidden;
}

.card::before {
  content: '';
  position: absolute;
  top: 0;
  left: 0;
  width: 100%;
  height: 5px;
  background: var(--gradient-rainbow);
}

.card:hover {
  transform: translateY(-8px) scale(1.02);
  box-shadow: var(--shadow-lg);
}

.card-img {
  width: 100%;
  height: 200px;
  object-fit: cover;
  border-radius: var(--radius-md);
  margin-bottom: var(--spacing-md);
}

.card-title {
  font-size: 1.5rem;
  margin-bottom: var(--spacing-sm);
  color: var(--color-dark);
}

.card-text {
  color: var(--color-gray);
  margin-bottom: var(--spacing-md);
}

/* ===== GRID SYSTEM ===== */
.grid {
  display: grid;
  gap: var(--spacing-lg);
}

.grid-2 {
  grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
}

.grid-3 {
  grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
}

.grid-4 {
  grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
}

/* ===== LEVEL BADGES ===== */
.level-badge {
  display: inline-block;
  padding: var(--spacing-xs) var(--spacing-md);
  border-radius: var(--radius-lg);
  font-weight: 600;
  font-size: 0.9rem;
  text-transform: uppercase;
  letter-spacing: 1px;
}

.level-beginner {
  background: linear-gradient(135deg, #a8edea 0%, #fed6e3 100%);
  color: var(--color-dark);
}

.level-intermediate {
  background: linear-gradient(135deg, #ffecd2 0%, #fcb69f 100%);
  color: var(--color-dark);
}

.level-advanced {
  background: linear-gradient(135deg, #ff9a9e 0%, #fecfef 100%);
  color: var(--color-dark);
}

/* ===== ANIMATIONS ===== */
@keyframes bounce {
  0%, 100% {
    transform: translateY(0);
  }
  50% {
    transform: translateY(-10px);
  }
}

@keyframes wiggle {
  0%, 100% {
    transform: rotate(0deg);
  }
  25% {
    transform: rotate(-5deg);
  }
  75% {
    transform: rotate(5deg);
  }
}

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

@keyframes shimmer {
  0% {
    background-position: -1000px 0;
  }
  100% {
    background-position: 1000px 0;
  }
}

@keyframes pulse {
  0%, 100% {
    transform: scale(1);
  }
  50% {
    transform: scale(1.05);
  }
}

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

/* Animation Helper Classes */
.animate-bounce {
  animation: bounce 2s ease infinite;
}

.animate-wiggle {
  animation: wiggle 1s ease infinite;
}

.animate-float {
  animation: float 3s ease-in-out infinite;
}

.animate-pulse {
  animation: pulse 2s ease infinite;
}

.animate-fadeIn {
  animation: fadeIn 0.6s ease;
}

/* ===== HERO SECTION ===== */
.hero {
  text-align: center;
  padding: var(--spacing-xxl) 0;
  position: relative;
}

.hero-title {
  font-size: 4rem;
  background: var(--gradient-rainbow);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
  margin-bottom: var(--spacing-md);
  animation: fadeIn 1s ease;
}

.hero-subtitle {
  font-size: 1.5rem;
  color: var(--color-gray);
  margin-bottom: var(--spacing-xl);
  animation: fadeIn 1s ease 0.2s backwards;
}

.hero-image {
  max-width: 400px;
  margin: var(--spacing-xl) auto;
  animation: float 3s ease-in-out infinite;
}

/* ===== VIDEO CARDS ===== */
.video-card {
  background: var(--color-white);
  border-radius: var(--radius-lg);
  overflow: hidden;
  box-shadow: var(--shadow-md);
  transition: all var(--transition-normal);
}

.video-card:hover {
  transform: translateY(-8px);
  box-shadow: var(--shadow-lg);
}

.video-wrapper {
  position: relative;
  padding-bottom: 56.25%; /* 16:9 aspect ratio */
  height: 0;
  overflow: hidden;
}

.video-wrapper iframe {
  position: absolute;
  top: 0;
  left: 0;
  width: 100%;
  height: 100%;
  border: none;
}

.video-info {
  padding: var(--spacing-md);
}

.video-title {
  font-size: 1.2rem;
  font-weight: 600;
  margin-bottom: var(--spacing-xs);
  color: var(--color-dark);
}

.video-description {
  color: var(--color-gray);
  font-size: 0.95rem;
}

/* ===== FLIP CARDS (Vocabulary) ===== */
.flip-card {
  perspective: 1000px;
  height: 300px;
  cursor: pointer;
}

.flip-card-inner {
  position: relative;
  width: 100%;
  height: 100%;
  text-align: center;
  transition: transform 0.6s;
  transform-style: preserve-3d;
}

.flip-card:hover .flip-card-inner,
.flip-card.flipped .flip-card-inner {
  transform: rotateY(180deg);
}

.flip-card-front, .flip-card-back {
  position: absolute;
  width: 100%;
  height: 100%;
  backface-visibility: hidden;
  border-radius: var(--radius-lg);
  display: flex;
  flex-direction: column;
  justify-content: center;
  align-items: center;
  padding: var(--spacing-md);
  box-shadow: var(--shadow-md);
}

.flip-card-front {
  background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
  color: white;
}

.flip-card-back {
  background: linear-gradient(135deg, #f093fb 0%, #f5576c 100%);
  color: white;
  transform: rotateY(180deg);
}

.flip-card-img {
  width: 150px;
  height: 150px;
  object-fit: contain;
  margin-bottom: var(--spacing-md);
  border-radius: var(--radius-md);
  background: white;
  padding: var(--spacing-sm);
}

.flip-card-word {
  font-size: 2rem;
  font-weight: 700;
  font-family: var(--font-display);
  margin-bottom: var(--spacing-sm);
}

.flip-card-pronunciation {
  font-size: 1.2rem;
  opacity: 0.9;
}

/* ===== GAME ELEMENTS ===== */
.game-container {
  background: var(--color-white);
  border-radius: var(--radius-lg);
  padding: var(--spacing-lg);
  box-shadow: var(--shadow-lg);
  margin: var(--spacing-xl) auto;
  max-width: 900px;
}

.game-canvas {
  width: 100%;
  border-radius: var(--radius-md);
  background: #f0f0f0;
  box-shadow: inset 0 2px 8px rgba(0,0,0,0.1);
}

.game-controls {
  margin-top: var(--spacing-md);
  display: flex;
  gap: var(--spacing-sm);
  justify-content: center;
  flex-wrap: wrap;
}

.score-display {
  text-align: center;
  font-size: 2rem;
  font-weight: 700;
  margin: var(--spacing-md) 0;
  color: var(--color-primary);
}

.task-display {
  background: var(--gradient-candy);
  color: white;
  padding: var(--spacing-md);
  border-radius: var(--radius-lg);
  text-align: center;
  font-size: 1.5rem;
  font-weight: 600;
  margin-bottom: var(--spacing-md);
  box-shadow: var(--shadow-md);
  animation: pulse 2s ease infinite;
}

/* ===== FORMS ===== */
.form-group {
  margin-bottom: var(--spacing-md);
}

.form-label {
  display: block;
  margin-bottom: var(--spacing-xs);
  font-weight: 600;
  color: var(--color-dark);
}

.form-input,
.form-textarea,
.form-select {
  width: 100%;
  padding: var(--spacing-sm);
  border: 2px solid var(--color-light-gray);
  border-radius: var(--radius-md);
  font-family: var(--font-primary);
  font-size: 1rem;
  transition: all var(--transition-normal);
}

.form-input:focus,
.form-textarea:focus,
.form-select:focus {
  outline: none;
  border-color: var(--color-primary);
  box-shadow: 0 0 0 3px rgba(255, 107, 107, 0.1);
}

.form-textarea {
  resize: vertical;
  min-height: 100px;
}

/* ===== MODAL ===== */
.modal {
  display: none;
  position: fixed;
  top: 0;
  left: 0;
  width: 100%;
  height: 100%;
  background: rgba(0, 0, 0, 0.7);
  z-index: 1000;
  justify-content: center;
  align-items: center;
  animation: fadeIn 0.3s ease;
}

.modal.active {
  display: flex;
}

.modal-content {
  background: var(--color-white);
  border-radius: var(--radius-lg);
  padding: var(--spacing-xl);
  max-width: 90%;
  max-height: 90%;
  overflow-y: auto;
  position: relative;
  animation: fadeIn 0.3s ease;
}

.modal-close {
  position: absolute;
  top: var(--spacing-md);
  right: var(--spacing-md);
  font-size: 2rem;
  background: none;
  border: none;
  cursor: pointer;
  color: var(--color-gray);
  transition: color var(--transition-fast);
}

.modal-close:hover {
  color: var(--color-primary);
}

/* ===== RESPONSIVE ===== */
@media (max-width: 768px) {
  html {
    font-size: 14px;
  }
  
  .hero-title {
    font-size: 2.5rem;
  }
  
  h1 {
    font-size: 2rem;
  }
  
  h2 {
    font-size: 1.8rem;
  }
  
  .grid-2, .grid-3, .grid-4 {
    grid-template-columns: 1fr;
  }
  
  .header-content {
    flex-direction: column;
    text-align: center;
  }
  
  .nav {
    width: 100%;
    justify-content: center;
  }
}

/* ===== UTILITY CLASSES ===== */
.text-center {
  text-align: center;
}

.mt-sm { margin-top: var(--spacing-sm); }
.mt-md { margin-top: var(--spacing-md); }
.mt-lg { margin-top: var(--spacing-lg); }
.mt-xl { margin-top: var(--spacing-xl); }

.mb-sm { margin-bottom: var(--spacing-sm); }
.mb-md { margin-bottom: var(--spacing-md); }
.mb-lg { margin-bottom: var(--spacing-lg); }
.mb-xl { margin-bottom: var(--spacing-xl); }

.p-sm { padding: var(--spacing-sm); }
.p-md { padding: var(--spacing-md); }
.p-lg { padding: var(--spacing-lg); }
.p-xl { padding: var(--spacing-xl); }

.hidden {
  display: none !important;
}

.visible {
  display: block !important;
}