/* CSS Variables */
:root {
  /* Colors */
  --primary-color: #6366F1;
  --primary-dark: #4F46E5;
  --secondary-color: #F59E0B;
  --accent-color: #EC4899;
  --success-color: #10B981;
  --warning-color: #F59E0B;
  --error-color: #EF4444;
  
  /* Neutral Colors */
  --white: #FFFFFF;
  --gray-50: #F9FAFB;
  --gray-100: #F3F4F6;
  --gray-200: #E5E7EB;
  --gray-300: #D1D5DB;
  --gray-400: #9CA3AF;
  --gray-500: #6B7280;
  --gray-600: #4B5563;
  --gray-700: #374151;
  --gray-800: #1F2937;
  --gray-900: #111827;
  
  /* Gradient Colors */
  --gradient-primary: linear-gradient(135deg, var(--primary-color) 0%, var(--accent-color) 100%);
  --gradient-secondary: linear-gradient(135deg, var(--secondary-color) 0%, #F97316 100%);
  --gradient-hero: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
  
  /* Typography */
  --font-family: 'Nunito', sans-serif;
  --font-size-xs: 0.75rem;
  --font-size-sm: 0.875rem;
  --font-size-base: 1rem;
  --font-size-lg: 1.125rem;
  --font-size-xl: 1.25rem;
  --font-size-2xl: 1.5rem;
  --font-size-3xl: 1.875rem;
  --font-size-4xl: 2.25rem;
  --font-size-5xl: 3rem;
  --font-size-6xl: 3.75rem;
  
  /* Font Weights */
  --font-weight-normal: 400;
  --font-weight-medium: 600;
  --font-weight-bold: 700;
  --font-weight-extrabold: 800;
  
  /* Spacing */
  --space-1: 0.25rem;
  --space-2: 0.5rem;
  --space-3: 0.75rem;
  --space-4: 1rem;
  --space-5: 1.25rem;
  --space-6: 1.5rem;
  --space-8: 2rem;
  --space-10: 2.5rem;
  --space-12: 3rem;
  --space-16: 4rem;
  --space-20: 5rem;
  --space-24: 6rem;
  
  /* Borders */
  --border-radius-sm: 0.375rem;
  --border-radius: 0.5rem;
  --border-radius-lg: 0.75rem;
  --border-radius-xl: 1rem;
  --border-radius-2xl: 1.5rem;
  --border-radius-full: 9999px;
  
  /* Shadows */
  --shadow-sm: 0 1px 2px 0 rgba(0, 0, 0, 0.05);
  --shadow: 0 1px 3px 0 rgba(0, 0, 0, 0.1), 0 1px 2px 0 rgba(0, 0, 0, 0.06);
  --shadow-md: 0 4px 6px -1px rgba(0, 0, 0, 0.1), 0 2px 4px -1px rgba(0, 0, 0, 0.06);
  --shadow-lg: 0 10px 15px -3px rgba(0, 0, 0, 0.1), 0 4px 6px -2px rgba(0, 0, 0, 0.05);
  --shadow-xl: 0 20px 25px -5px rgba(0, 0, 0, 0.1), 0 10px 10px -5px rgba(0, 0, 0, 0.04);
  
  /* Transitions */
  --transition-fast: 150ms ease-in-out;
  --transition-normal: 300ms ease-in-out;
  --transition-slow: 500ms ease-in-out;
  
  /* Container */
  --container-max-width: 1200px;
}

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

html {
  scroll-behavior: smooth;
}

body {
  font-family: var(--font-family);
  font-size: var(--font-size-base);
  font-weight: var(--font-weight-normal);
  line-height: 1.6;
  color: var(--gray-800);
  background-color: var(--white);
  overflow-x: hidden;
}

/* Container */
.container {
  max-width: var(--container-max-width);
  margin: 0 auto;
  padding: 0 var(--space-4);
}

@media (min-width: 640px) {
  .container {
    padding: 0 var(--space-6);
  }
}

@media (min-width: 1024px) {
  .container {
    padding: 0 var(--space-8);
  }
}

/* Section */
.section {
  padding: var(--space-16) 0;
}

@media (min-width: 768px) {
  .section {
    padding: var(--space-20) 0;
  }
}

/* Section Header */
.section__header {
  text-align: center;
  margin-bottom: var(--space-16);
}

.section__title {
  font-size: var(--font-size-3xl);
  font-weight: var(--font-weight-extrabold);
  color: var(--gray-900);
  margin-bottom: var(--space-4);
}

@media (min-width: 768px) {
  .section__title {
    font-size: var(--font-size-4xl);
  }
}

.section__subtitle {
  font-size: var(--font-size-lg);
  color: var(--gray-600);
  max-width: 600px;
  margin: 0 auto;
}

/* Buttons */
.btn {
  display: inline-flex;
  align-items: center;
  gap: var(--space-2);
  padding: var(--space-3) var(--space-6);
  font-size: var(--font-size-base);
  font-weight: var(--font-weight-medium);
  text-decoration: none;
  border-radius: var(--border-radius-lg);
  transition: all var(--transition-normal);
  cursor: pointer;
  border: none;
}

.btn--primary {
  background: var(--gradient-primary);
  color: var(--white);
  box-shadow: var(--shadow-md);
}

.btn--primary:hover {
  transform: translateY(-2px);
  box-shadow: var(--shadow-lg);
}

.btn--secondary {
  background-color: var(--white);
  color: var(--primary-color);
  border: 2px solid var(--primary-color);
}

.btn--secondary:hover {
  background-color: var(--primary-color);
  color: var(--white);
  transform: translateY(-2px);
}

/* Header */
.header {
  position: fixed;
  top: 0;
  left: 0;
  width: 100%;
  background-color: rgba(255, 255, 255, 0.95);
  backdrop-filter: blur(10px);
  border-bottom: 1px solid var(--gray-200);
  z-index: 1000;
  transition: all var(--transition-normal);
}

.nav {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: var(--space-4) 0;
}

.nav__logo {
  display: flex;
  align-items: center;
  gap: var(--space-3);
}

.nav__logo-img {
  width: 40px;
  height: 40px;
  border-radius: var(--border-radius);
}

.nav__logo-text {
  font-size: var(--font-size-xl);
  font-weight: var(--font-weight-extrabold);
  color: var(--primary-color);
}

.nav__menu {
  display: none;
}

@media (min-width: 768px) {
  .nav__menu {
    display: block;
  }
}

.nav__list {
  display: flex;
  align-items: center;
  gap: var(--space-8);
  list-style: none;
}

.nav__link {
  font-weight: var(--font-weight-medium);
  color: var(--gray-700);
  text-decoration: none;
  transition: color var(--transition-fast);
}

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

.nav__toggle {
  display: block;
  font-size: var(--font-size-xl);
  color: var(--gray-700);
  cursor: pointer;
}

@media (min-width: 768px) {
  .nav__toggle {
    display: none;
  }
}

/* Hero Section */
.hero {
  background: var(--gradient-hero);
  color: var(--white);
  padding-top: var(--space-24);
  min-height: 100vh;
  display: flex;
  align-items: center;
  position: relative;
  overflow: hidden;
}

.hero::before {
  content: '';
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  bottom: 0;
  background: url('data:image/svg+xml,<svg xmlns="http://www.w3.org/2000/svg" viewBox="0 0 100 100"><defs><pattern id="stars" x="0" y="0" width="20" height="20" patternUnits="userSpaceOnUse"><circle cx="10" cy="10" r="1" fill="rgba(255,255,255,0.1)"/></pattern></defs><rect width="100" height="100" fill="url(%23stars)"/></svg>');
  opacity: 0.3;
}

.hero__container {
  display: grid;
  gap: var(--space-12);
  align-items: center;
  position: relative;
  z-index: 1;
}

@media (min-width: 1024px) {
  .hero__container {
    grid-template-columns: 1fr 1fr;
    gap: var(--space-16);
  }
}

.hero__content {
  text-align: center;
}

@media (min-width: 1024px) {
  .hero__content {
    text-align: left;
  }
}

.hero__title {
  font-size: var(--font-size-4xl);
  font-weight: var(--font-weight-extrabold);
  line-height: 1.2;
  margin-bottom: var(--space-6);
}

@media (min-width: 768px) {
  .hero__title {
    font-size: var(--font-size-5xl);
  }
}

@media (min-width: 1024px) {
  .hero__title {
    font-size: var(--font-size-6xl);
  }
}

.hero__title-gradient {
  background: linear-gradient(135deg, #FFD700 0%, #FFA500 100%);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
}

.hero__description {
  font-size: var(--font-size-lg);
  opacity: 0.9;
  margin-bottom: var(--space-8);
  max-width: 500px;
  margin-left: auto;
  margin-right: auto;
}

@media (min-width: 1024px) {
  .hero__description {
    margin-left: 0;
    margin-right: 0;
  }
}

.hero__buttons {
  display: flex;
  flex-direction: column;
  gap: var(--space-4);
  margin-bottom: var(--space-12);
}

@media (min-width: 640px) {
  .hero__buttons {
    flex-direction: row;
    justify-content: center;
  }
}

@media (min-width: 1024px) {
  .hero__buttons {
    justify-content: flex-start;
  }
}

.hero__stats {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: var(--space-6);
  text-align: center;
}

.hero__stat-number {
  display: block;
  font-size: var(--font-size-2xl);
  font-weight: var(--font-weight-extrabold);
  color: var(--secondary-color);
}

.hero__stat-text {
  font-size: var(--font-size-sm);
  opacity: 0.8;
}

.hero__image {
  position: relative;
  text-align: center;
}

.hero__img {
  width: 100%;
  max-width: 500px;
  height: auto;
  border-radius: var(--border-radius-2xl);
  box-shadow: var(--shadow-xl);
}

.hero__floating-elements {
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  bottom: 0;
}

.floating-star,
.floating-cloud {
  position: absolute;
  font-size: var(--font-size-2xl);
  animation: float 3s ease-in-out infinite;
}

.floating-star--1 {
  top: 10%;
  left: 10%;
  animation-delay: 0s;
}

.floating-star--2 {
  top: 20%;
  right: 15%;
  animation-delay: 1s;
}

.floating-star--3 {
  bottom: 30%;
  left: 5%;
  animation-delay: 2s;
}

.floating-cloud--1 {
  top: 15%;
  right: 10%;
  animation-delay: 0.5s;
}

.floating-cloud--2 {
  bottom: 20%;
  right: 20%;
  animation-delay: 1.5s;
}

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

/* Features Section */
.features {
  background-color: var(--gray-50);
}

.features__grid {
  display: grid;
  grid-template-columns: 1fr;
  gap: var(--space-8);
}

@media (min-width: 768px) {
  .features__grid {
    grid-template-columns: repeat(2, 1fr);
  }
}

@media (min-width: 1024px) {
  .features__grid {
    grid-template-columns: repeat(3, 1fr);
  }
}

.feature__card {
  background-color: var(--white);
  padding: var(--space-8);
  border-radius: var(--border-radius-xl);
  box-shadow: var(--shadow);
  text-align: center;
  transition: all var(--transition-normal);
}

.feature__card:hover {
  transform: translateY(-5px);
  box-shadow: var(--shadow-lg);
}

.feature__icon {
  width: 80px;
  height: 80px;
  background: var(--gradient-primary);
  border-radius: var(--border-radius-full);
  display: flex;
  align-items: center;
  justify-content: center;
  margin: 0 auto var(--space-6);
  color: var(--white);
  font-size: var(--font-size-2xl);
}

.feature__title {
  font-size: var(--font-size-xl);
  font-weight: var(--font-weight-bold);
  color: var(--gray-900);
  margin-bottom: var(--space-4);
}

.feature__description {
  color: var(--gray-600);
  line-height: 1.6;
}

/* Age Groups Section */
.age-groups__grid {
  display: grid;
  grid-template-columns: 1fr;
  gap: var(--space-12);
}

@media (min-width: 1024px) {
  .age-groups__grid {
    grid-template-columns: repeat(3, 1fr);
    gap: var(--space-8);
  }
}

.age-group__card {
  background-color: var(--white);
  border-radius: var(--border-radius-2xl);
  overflow: hidden;
  box-shadow: var(--shadow-lg);
  transition: all var(--transition-normal);
}

.age-group__card:hover {
  transform: translateY(-10px);
  box-shadow: var(--shadow-xl);
}

.age-group__image {
  height: 200px;
  overflow: hidden;
}

.age-group__img {
  width: 100%;
  height: 100%;
  object-fit: cover;
  transition: transform var(--transition-normal);
}

.age-group__card:hover .age-group__img {
  transform: scale(1.1);
}

.age-group__content {
  padding: var(--space-6);
}

.age-group__title {
  font-size: var(--font-size-2xl);
  font-weight: var(--font-weight-bold);
  color: var(--primary-color);
  margin-bottom: var(--space-4);
}

.age-group__description {
  color: var(--gray-600);
  margin-bottom: var(--space-6);
  line-height: 1.6;
}

.age-group__features {
  list-style: none;
  space-y: var(--space-2);
}

.age-group__features li {
  margin-bottom: var(--space-2);
  color: var(--gray-700);
  font-weight: var(--font-weight-medium);
}

/* Screenshots Section */
.screenshots {
  background-color: var(--gray-50);
}

.screenshots__container {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
  gap: var(--space-8);
}

.screenshot__item {
  text-align: center;
}

.screenshot__img {
  width: 100%;
  max-width: 300px;
  height: auto;
  border-radius: var(--border-radius-xl);
  box-shadow: var(--shadow-lg);
  transition: transform var(--transition-normal);
}

.screenshot__img:hover {
  transform: scale(1.05);
}

.screenshot__title {
  font-size: var(--font-size-lg);
  font-weight: var(--font-weight-medium);
  color: var(--gray-800);
  margin-top: var(--space-4);
}

/* Download Section */
.download {
  background: var(--gradient-primary);
  color: var(--white);
}

.download__container {
  display: grid;
  gap: var(--space-12);
  align-items: center;
}

@media (min-width: 1024px) {
  .download__container {
    grid-template-columns: 1fr 1fr;
    gap: var(--space-16);
  }
}

.download__content {
  text-align: center;
}

@media (min-width: 1024px) {
  .download__content {
    text-align: left;
  }
}

.download__title {
  font-size: var(--font-size-3xl);
  font-weight: var(--font-weight-extrabold);
  margin-bottom: var(--space-6);
}

@media (min-width: 768px) {
  .download__title {
    font-size: var(--font-size-4xl);
  }
}

.download__description {
  font-size: var(--font-size-lg);
  opacity: 0.9;
  margin-bottom: var(--space-8);
  line-height: 1.6;
}

.download__buttons {
  display: flex;
  flex-direction: column;
  gap: var(--space-4);
  margin-bottom: var(--space-8);
}

@media (min-width: 640px) {
  .download__buttons {
    flex-direction: row;
    justify-content: center;
  }
}

@media (min-width: 1024px) {
  .download__buttons {
    justify-content: flex-start;
  }
}

.download__btn {
  display: block;
  transition: transform var(--transition-fast);
}

.download__btn:hover {
  transform: scale(1.05);
}

.download__btn img {
  height: 60px;
  width: auto;
}

.download__info {
  display: flex;
  flex-wrap: wrap;
  gap: var(--space-6);
  justify-content: center;
  font-size: var(--font-size-sm);
  opacity: 0.8;
}

@media (min-width: 1024px) {
  .download__info {
    justify-content: flex-start;
  }
}

.download__image {
  text-align: center;
}

.download__img {
  width: 100%;
  max-width: 400px;
  height: auto;
}

/* Footer */
.footer {
  background-color: var(--gray-900);
  color: var(--white);
  padding: var(--space-16) 0 var(--space-8);
}

.footer__content {
  display: grid;
  gap: var(--space-12);
  margin-bottom: var(--space-12);
}

@media (min-width: 1024px) {
  .footer__content {
    grid-template-columns: 1fr 1fr;
    gap: var(--space-16);
  }
}

.footer__brand {
  text-align: center;
}

@media (min-width: 1024px) {
  .footer__brand {
    text-align: left;
  }
}

.footer__logo {
  display: flex;
  align-items: center;
  justify-content: center;
  gap: var(--space-3);
  margin-bottom: var(--space-6);
}

@media (min-width: 1024px) {
  .footer__logo {
    justify-content: flex-start;
  }
}

.footer__logo-img {
  width: 40px;
  height: 40px;
  border-radius: var(--border-radius);
}

.footer__logo-text {
  font-size: var(--font-size-xl);
  font-weight: var(--font-weight-extrabold);
  color: var(--secondary-color);
}

.footer__description {
  color: var(--gray-300);
  margin-bottom: var(--space-6);
  line-height: 1.6;
  max-width: 400px;
  margin-left: auto;
  margin-right: auto;
}

@media (min-width: 1024px) {
  .footer__description {
    margin-left: 0;
    margin-right: 0;
  }
}

.footer__developer {
  display: flex;
  align-items: center;
  justify-content: center;
  gap: var(--space-2);
  font-size: var(--font-size-sm);
}

@media (min-width: 1024px) {
  .footer__developer {
    justify-content: flex-start;
  }
}

.footer__developer-text {
  color: var(--gray-400);
}

.footer__developer-name {
  color: var(--secondary-color);
  font-weight: var(--font-weight-medium);
}

.footer__links {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(150px, 1fr));
  gap: var(--space-8);
  text-align: center;
}

@media (min-width: 1024px) {
  .footer__links {
    text-align: left;
  }
}

.footer__title {
  font-size: var(--font-size-lg);
  font-weight: var(--font-weight-bold);
  margin-bottom: var(--space-4);
  color: var(--white);
}

.footer__list {
  list-style: none;
  space-y: var(--space-2);
}

.footer__list li {
  margin-bottom: var(--space-2);
}

.footer__link {
  color: var(--gray-300);
  text-decoration: none;
  transition: color var(--transition-fast);
}

.footer__link:hover {
  color: var(--secondary-color);
}

.footer__bottom {
  display: flex;
  flex-direction: column;
  gap: var(--space-4);
  align-items: center;
  justify-content: space-between;
  padding-top: var(--space-8);
  border-top: 1px solid var(--gray-800);
  text-align: center;
}

@media (min-width: 768px) {
  .footer__bottom {
    flex-direction: row;
    text-align: left;
  }
}

.footer__copyright {
  color: var(--gray-400);
  font-size: var(--font-size-sm);
}

.footer__social {
  display: flex;
  gap: var(--space-4);
}

.footer__social-link {
  width: 40px;
  height: 40px;
  background-color: var(--gray-800);
  color: var(--gray-300);
  border-radius: var(--border-radius-full);
  display: flex;
  align-items: center;
  justify-content: center;
  text-decoration: none;
  transition: all var(--transition-fast);
}

.footer__social-link:hover {
  background-color: var(--primary-color);
  color: var(--white);
  transform: translateY(-2px);
}

/* Responsive Typography */
@media (max-width: 640px) {
  .hero__title {
    font-size: var(--font-size-3xl);
  }
  
  .section__title {
    font-size: var(--font-size-2xl);
  }
  
  .download__title {
    font-size: var(--font-size-2xl);
  }
}

/* Animations */
@keyframes fadeInUp {
  from {
    opacity: 0;
    transform: translateY(30px);
  }
  to {
    opacity: 1;
    transform: translateY(0);
  }
}

.fade-in-up {
  animation: fadeInUp 0.6s ease-out;
}

/* Loading Animation */
@keyframes pulse {
  0%, 100% {
    opacity: 1;
  }
  50% {
    opacity: 0.5;
  }
}

.pulse {
  animation: pulse 2s cubic-bezier(0.4, 0, 0.6, 1) infinite;
}

/* Utility Classes */
.text-center {
  text-align: center;
}

.text-left {
  text-align: left;
}

.text-right {
  text-align: right;
}

.hidden {
  display: none;
}

@media (min-width: 768px) {
  .md\:block {
    display: block;
  }
  
  .md\:hidden {
    display: none;
  }
}

@media (min-width: 1024px) {
  .lg\:block {
    display: block;
  }
  
  .lg\:hidden {
    display: none;
  }
}