:root {
  --primary: #00C853; /* Canlı yeşil */
  --secondary: #00BCD4; /* Turkuaz */
  --accent: #FFCA28; /* Sarı */
  --dark: #00695C; /* Koyu turkuaz */
  --light: #E0F7FA; /* Açık turkuaz */
  --text: #263238; /* Koyu gri */
  --white: #FFFFFF; /* Beyaz */
}

* {
  margin: 0;
  padding: 0;
  box-sizing: border-box;
  font-family: 'Poppins', sans-serif;
}

body {
  background: linear-gradient(180deg, #E0F7FA, #FFFFFF);
  color: var(--text);
  line-height: 1.7;
}

header {
  background: linear-gradient(90deg, var(--primary), var(--secondary));
  color: var(--white);
  padding: 1rem 2rem;
  display: flex;
  justify-content: space-between;
  align-items: center;
  position: sticky;
  top: 0;
  z-index: 100;
  border-bottom: 3px solid var(--accent);
}

.logo {
  font-size: 2rem;
  font-weight: 700;
}

.logo span {
  color: var(--accent);
}

nav a {
  color: var(--white);
  text-decoration: none;
  margin-left: 1.5rem;
  font-size: 1.1rem;
  font-weight: 500;
  transition: color 0.3s, transform 0.3s;
}

nav a:hover {
  color: var(--accent);
  transform: scale(1.1);
}

.hero {
  background: linear-gradient(135deg, var(--secondary), var(--primary));
  color: var(--white);
  text-align: center;
  padding: 6rem 2rem;
  clip-path: polygon(0 0, 100% 0, 100% 80%, 0 100%);
}

.hero h1 {
  font-size: 3.5rem;
  font-weight: 700;
  margin-bottom: 1.5rem;
  text-shadow: 0 2px 4px rgba(0, 0, 0, 0.2);
}

.hero p {
  font-size: 1.4rem;
  max-width: 600px;
  margin: 0 auto 2rem;
}

.cta-button {
  background: var(--accent);
  color: var(--dark);
  border: none;
  padding: 1.2rem 3rem;
  font-size: 1.2rem;
  font-weight: 600;
  border-radius: 50px;
  cursor: pointer;
  box-shadow: 0 4px 8px rgba(0, 0, 0, 0.2);
  transition: transform 0.3s, background 0.3s;
}

.cta-button:hover {
  background: #FFEE58;
  transform: scale(1.1) rotate(2deg);
}

.container {
  max-width: 1000px;
  margin: 0 auto;
  padding: 0 2rem;
}

.stats {
  display: flex;
  justify-content: space-around;
  flex-wrap: wrap;
  background: var(--light);
  padding: 2rem;
  border-radius: 15px;
  margin: 3rem 0;
  box-shadow: 0 6px 12px rgba(0, 0, 0, 0.1);
}

.stat-item {
  text-align: center;
  padding: 1rem;
  min-width: 180px;
}

.stat-circle {
  font-size: 2rem;
  font-weight: 700;
  color: var(--white);
  background: var(--primary);
  width: 100px;
  height: 100px;
  line-height: 100px;
  border-radius: 50%;
  margin: 0 auto 0.5rem;
  box-shadow: 0 4px 8px rgba(0, 0, 0, 0.2);
  transition: transform 0.3s;
}

.stat-item:hover .stat-circle {
  transform: scale(1.1);
}

.features {
  margin: 4rem 0;
  text-align: center;
}

.features h2 {
  font-size: 2.8rem;
  color: var(--dark);
  margin-bottom: 2rem;
}

.feature-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(260px, 1fr));
  gap: 1.5rem;
}

.feature-card {
  background: var(--white);
  border-radius: 12px;
  padding: 2rem;
  box-shadow: 0 6px 12px rgba(0, 0, 0, 0.1);
  transition: transform 0.3s, box-shadow 0.3s;
}

.feature-card:hover {
  transform: translateY(-10px) scale(1.02);
  box-shadow: 0 10px 20px rgba(0, 0, 0, 0.15);
}

.feature-icon {
  font-size: 2.5rem;
  display: block;
  margin-bottom: 1rem;
}

.feature-card h3 {
  color: var(--primary);
  font-size: 1.6rem;
  margin-bottom: 0.8rem;
}

.demo-section {
  margin: 5rem 0;
  text-align: center;
  background: var(--light);
  padding: 3rem 2rem;
  border-radius: 15px;
}

.demo-section h2 {
  font-size: 2.8rem;
  color: var(--dark);
  margin-bottom: 1rem;
}

.demo-section p {
  font-size: 1.3rem;
  max-width: 500px;
  margin: 0 auto 2rem;
}

.demo-container {
  display: flex;
  justify-content: center;
  gap: 2rem;
  flex-wrap: wrap;
}

.demo-card {
  background: var(--white);
  border-radius: 15px;
  padding: 2rem;
  width: 380px;
  box-shadow: 0 8px 16px rgba(0, 0, 0, 0.1);
  transition: transform 0.3s;
}

.demo-card:hover {
  transform: translateY(-8px);
}

.demo-card.customer {
  border: 3px solid var(--secondary);
}

.demo-card.business {
  border: 3px solid var(--primary);
}

.demo-card h3 {
  font-size: 1.7rem;
  color: var(--dark);
  margin-bottom: 1.5rem;
}

.qr-code {
  width: 180px;
  height: 180px;
  margin: 1.5rem auto;
  background: var(--white);
  border-radius: 12px;
  box-shadow: 0 4px 8px rgba(0, 0, 0, 0.1);
  overflow: hidden;
  transition: transform 0.3s;
}

.qr-code:hover {
  transform: scale(1.05);
}

.qr-code img {
  width: 100%;
  height: 100%;
}

.receipt {
  background: #E8F5E9;
  border: 2px dashed var(--primary);
  padding: 1.5rem;
  margin-top: 1.5rem;
  font-family: 'Courier New', monospace;
  text-align: left;
  font-size: 0.95rem;
  border-radius: 8px;
}

.pos-screen {
  background: #37474F;
  color: #CFD8DC;
  padding: 1.5rem;
  border-radius: 10px;
  font-family: 'Courier New', monospace;
  min-height: 200px;
  margin-bottom: 1.5rem;
  border: 1px solid var(--secondary);
}

.pos-item {
  display: flex;
  justify-content: space-between;
  padding: 0.6rem 0;
  border-bottom: 1px dotted #607D8B;
}

.pos-total {
  font-weight: 600;
  margin-top: 1rem;
  padding: 1rem 0;
  background: var(--secondary);
  color: var(--white);
  border-radius: 6px;
  display: flex;
  justify-content: space-between;
}

.pos-buttons {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 0.8rem;
  margin-top: 1rem;
}

.pos-button {
  background: #607D8B;
  color: var(--white);
  border: none;
  padding: 1rem;
  border-radius: 8px;
  font-size: 1rem;
  font-weight: 500;
  cursor: pointer;
  transition: background 0.3s, transform 0.3s;
}

.pos-button:hover {
  background: #78909C;
  transform: scale(1.05);
}

.pos-button.primary {
  background: var(--primary);
}

.pos-button.primary:hover {
  background: var(--dark);
  transform: scale(1.1) rotate(3deg);
}

.contact {
  text-align: center;
  margin: 4rem 0;
}

.contact h2 {
  font-size: 2.5rem;
  color: var(--dark);
  margin-bottom: 1rem;
}

.contact p {
  font-size: 1.2rem;
  max-width: 500px;
  margin: 0 auto;
}

footer {
  background: var(--dark);
  color: var(--white);
  text-align: center;
  padding: 1.5rem;
  font-size: 1rem;
  border-top: 3px solid var(--accent);
}

@media (max-width: 768px) {
  .hero h1 {
      font-size: 2.5rem;
  }

  .hero p {
      font-size: 1.1rem;
  }

  .stats {
      flex-direction: column;
      gap: 1.5rem;
  }

  .demo-container {
      flex-direction: column;
      align-items: center;
  }

  .demo-card {
      width: 100%;
      max-width: 340px;
  }

  nav {
      font-size: 0.9rem;
  }
}

@media (max-width: 480px) {
  .container {
      padding: 0 1rem;
  }

  .hero {
      padding: 4rem 1rem;
  }

  .feature-grid {
      grid-template-columns: 1fr;
  }

  .pos-screen {
      min-height: 180px;
  }

  .cta-button {
      padding: 1rem 2rem;
  }
}