:root {
  --primary-color: #4c6ef5;
  --primary-dark: #364fc7;
  --primary-light: #748ffc;
  --secondary-color: #15aabf;
  --text-color: #343a40;
  --text-light: #868e96;
  --bg-color: #ffffff;
  --bg-light: #f8f9fa;
  --bg-dark: #e9ecef;
  --border-color: #dee2e6;
  --success-color: #40c057;
  --danger-color: #fa5252;
  --warning-color: #fd7e14;
  --transition: all 0.3s ease;
  --box-shadow: 0 4px 6px rgba(0, 0, 0, 0.1);
  --border-radius: 8px;
}

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

body {
  color: var(--text-color);
  background-color: var(--bg-light);
  line-height: 1.6;
}

a {
  text-decoration: none;
  color: var(--primary-color);
  transition: var(--transition);
}

a:hover {
  color: var(--primary-dark);
}

ul {
  list-style: none;
}

img {
  max-width: 100%;
  height: auto;
}

.container {
  width: 100%;
  max-width: 1200px;
  margin: 0 auto;
  padding: 0 20px;
}

/* Typography */
h1, h2, h3, h4, h5 {
  line-height: 1.3;
  font-weight: 600;
  color: var(--text-color);
}

.section-title {
  font-size: 2rem;
  text-align: center;
  margin-bottom: 2rem;
  color: var(--primary-dark);
}

/* Buttons */
.btn {
  display: inline-block;
  padding: 12px 25px;
  border-radius: var(--border-radius);
  border: none;
  cursor: pointer;
  font-weight: 500;
  transition: var(--transition);
  text-align: center;
}

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

.btn-primary:hover {
  background-color: var(--primary-dark);
  color: white;
}

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

.btn-secondary:hover {
  background-color: #1098a8;
  color: white;
}

/* Header & Navigation */
header {
  position: fixed;
  top: 0;
  left: 0;
  width: 100%;
  background-color: rgba(255, 255, 255, 0.95);
  box-shadow: 0 2px 10px rgba(0, 0, 0, 0.1);
  z-index: 1000;
  transition: var(--transition);
}

header.scrolled {
  box-shadow: 0 5px 15px rgba(0, 0, 0, 0.1);
}

nav {
  display: flex;
  justify-content: space-between;
  align-items: center;
  height: 70px;
}

.logo {
  display: flex;
  align-items: center;
}

.logo i {
  font-size: 1.8rem;
  color: var(--primary-color);
  margin-right: 10px;
}

.logo h1 {
  font-size: 1.5rem;
  font-weight: 600;
  color: var(--primary-dark);
}

.nav-links {
  display: flex;
}

.nav-links li {
  margin-left: 30px;
}

.nav-links a {
  color: var(--text-color);
  font-weight: 500;
}

.nav-links a:hover {
  color: var(--primary-color);
}

.hamburger {
  display: none;
  cursor: pointer;
  flex-direction: column;
  justify-content: space-between;
  width: 30px;
  height: 21px;
}

.hamburger span {
  display: block;
  height: 3px;
  width: 100%;
  background-color: var(--text-color);
  transition: var(--transition);
}

/* Hero Section */
.hero {
  padding: 140px 0 80px;
  background: linear-gradient(180deg, #f5f7ff 0%, #ffffff 100%);
}

.hero .container {
  display: flex;
  align-items: center;
  justify-content: space-between;
}

.hero-content {
  max-width: 600px;
}

.hero-content h1 {
  font-size: 3rem;
  margin-bottom: 15px;
  color: var(--primary-dark);
}

.tagline {
  font-size: 1.5rem;
  font-weight: 500;
  margin-bottom: 20px;
  color: var(--secondary-color);
}

.description {
  margin-bottom: 30px;
  color: var(--text-light);
  font-size: 1.1rem;
}

.cta-buttons {
  display: flex;
  gap: 15px;
}

.hero-image {
  flex-shrink: 0;
  max-width: 500px;
}

/* Converter Section */
.converter-section {
  padding: 80px 0;
  background-color: var(--bg-color);
}

.converter-tool {
  max-width: 800px;
  margin: 0 auto;
  background-color: white;
  padding: 30px;
  border-radius: var(--border-radius);
  box-shadow: var(--box-shadow);
}

.category-selector {
  margin-bottom: 25px;
}

.category-selector select {
  width: 100%;
  padding: 12px;
  border-radius: var(--border-radius);
  border: 1px solid var(--border-color);
  font-size: 1rem;
  color: var(--text-color);
  background-color: white;
  cursor: pointer;
}

.conversion-box {
  display: flex;
  align-items: center;
  gap: 20px;
  margin-bottom: 25px;
}

.input-group {
  flex: 1;
  display: flex;
  flex-direction: column;
  gap: 10px;
}

.input-group input, .input-group select {
  width: 100%;
  padding: 12px;
  border-radius: var(--border-radius);
  border: 1px solid var(--border-color);
  font-size: 1rem;
}

.swap-btn button {
  width: 40px;
  height: 40px;
  border-radius: 50%;
  background-color: var(--primary-light);
  color: white;
  border: none;
  cursor: pointer;
  display: flex;
  align-items: center;
  justify-content: center;
  transition: var(--transition);
}

.swap-btn button:hover {
  background-color: var(--primary-color);
}

#convert-btn {
  width: 100%;
  padding: 14px;
  font-size: 1.1rem;
}

.formula-display {
  margin-top: 20px;
  padding: 15px;
  background-color: var(--bg-light);
  border-radius: var(--border-radius);
  color: var(--text-light);
  text-align: center;
  font-style: italic;
}

/* Features Section */
.features {
  padding: 80px 0;
  background-color: var(--bg-light);
}

.features-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
  gap: 30px;
}

.feature-card {
  background-color: white;
  padding: 30px;
  border-radius: var(--border-radius);
  box-shadow: var(--box-shadow);
  transition: var(--transition);
}

.feature-card:hover {
  transform: translateY(-5px);
  box-shadow: 0 8px 15px rgba(0, 0, 0, 0.1);
}

.feature-card .icon {
  width: 60px;
  height: 60px;
  background-color: var(--primary-light);
  color: white;
  border-radius: 50%;
  display: flex;
  align-items: center;
  justify-content: center;
  margin-bottom: 20px;
  font-size: 1.5rem;
}

.feature-card h3 {
  margin-bottom: 15px;
  font-size: 1.2rem;
}

/* Categories Section */
.categories {
  padding: 80px 0;
  background-color: white;
}

.categories-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
  gap: 25px;
}

.category-card {
  background-color: var(--bg-light);
  padding: 25px 20px;
  border-radius: var(--border-radius);
  text-align: center;
  transition: var(--transition);
  cursor: pointer;
}

.category-card:hover {
  background-color: var(--primary-light);
  color: white;
}

.category-card i {
  font-size: 2.5rem;
  color: var(--primary-color);
  margin-bottom: 15px;
  transition: var(--transition);
}

.category-card:hover i {
  color: white;
}

.category-card h3 {
  margin-bottom: 10px;
  transition: var(--transition);
}

.category-card:hover h3 {
  color: white;
}

.category-card p {
  font-size: 0.9rem;
  transition: var(--transition);
}

.category-card:hover p {
  color: rgba(255, 255, 255, 0.9);
}

/* Screenshots Section */
.screenshots {
  padding: 80px 0;
  background-color: var(--bg-light);
}

.screenshot-carousel {
  display: flex;
  overflow-x: auto;
  scroll-snap-type: x mandatory;
  gap: 20px;
  padding-bottom: 20px;
  scrollbar-width: none;
  -ms-overflow-style: none;
}

.screenshot-carousel::-webkit-scrollbar {
  display: none;
}

.screenshot {
  flex: 0 0 300px;
  scroll-snap-align: center;
  text-align: center;
}

.screenshot img {
  border-radius: var(--border-radius);
  box-shadow: var(--box-shadow);
  margin-bottom: 10px;
}

.carousel-controls {
  display: flex;
  justify-content: center;
  align-items: center;
  margin-top: 20px;
}

.carousel-controls button {
  background: none;
  border: none;
  font-size: 1.5rem;
  color: var(--primary-color);
  cursor: pointer;
  margin: 0 15px;
}

.carousel-indicators {
  display: flex;
  gap: 8px;
}

.carousel-indicators span {
  display: inline-block;
  width: 10px;
  height: 10px;
  border-radius: 50%;
  background-color: var(--border-color);
  cursor: pointer;
}

.carousel-indicators span.active {
  background-color: var(--primary-color);
}

/* Download Section */
.download {
  padding: 80px 0;
  background-color: white;
}

.download-description {
  max-width: 700px;
  margin: 0 auto 40px;
  text-align: center;
  color: var(--text-light);
}

.download-buttons {
  display: flex;
  justify-content: center;
  gap: 20px;
  margin-bottom: 60px;
}

.download-btn {
  display: flex;
  align-items: center;
  background-color: #000;
  color: white;
  padding: 10px 20px;
  border-radius: var(--border-radius);
  transition: var(--transition);
}

.download-btn:hover {
  background-color: #333;
  color: white;
}

.download-btn i {
  font-size: 2rem;
  margin-right: 15px;
}

.download-btn span {
  display: flex;
  flex-direction: column;
}

.download-btn small {
  font-size: 0.7rem;
  opacity: 0.7;
}

.subscription-info {
  max-width: 900px;
  margin: 0 auto;
}

.subscription-info h3 {
  text-align: center;
  margin-bottom: 30px;
  font-size: 1.5rem;
}

.subscription-plans {
  display: flex;
  gap: 30px;
  justify-content: center;
  flex-wrap: wrap;
}

.plan {
  background-color: var(--bg-light);
  padding: 40px 30px;
  border-radius: var(--border-radius);
  text-align: center;
  flex: 1 1 300px;
  max-width: 400px;
  position: relative;
}

.plan.premium {
  background-color: var(--primary-light);
  color: white;
  transform: scale(1.05);
  z-index: 1;
  box-shadow: 0 8px 20px rgba(0, 0, 0, 0.15);
}

.popular-tag {
  position: absolute;
  top: -15px;
  right: 30px;
  background-color: var(--warning-color);
  color: white;
  padding: 5px 15px;
  border-radius: 20px;
  font-size: 0.8rem;
  font-weight: 500;
}

.plan h4 {
  font-size: 1.3rem;
  margin-bottom: 10px;
}

.plan.premium h4, .plan.premium .price {
  color: white;
}

.price {
  font-size: 2rem;
  font-weight: 600;
  margin-bottom: 25px;
  color: var(--primary-dark);
}

.price span {
  font-size: 1rem;
  font-weight: normal;
}

.plan ul {
  margin-bottom: 30px;
  text-align: left;
}

.plan li {
  margin-bottom: 10px;
  position: relative;
  padding-left: 20px;
}

.plan li::before {
  content: "\f00c";
  font-family: "Font Awesome 5 Free";
  font-weight: 900;
  position: absolute;
  left: 0;
  color: var(--success-color);
}

.plan.premium li::before {
  color: white;
}

.plan .btn {
  width: 100%;
}

/* Testimonials */
.testimonials {
  padding: 80px 0;
  background-color: var(--bg-light);
}

.testimonials-slider {
  max-width: 800px;
  margin: 0 auto;
  overflow: hidden;
}

.testimonial {
  padding: 30px;
  background-color: white;
  border-radius: var(--border-radius);
  box-shadow: var(--box-shadow);
}

.quote {
  font-style: italic;
  margin-bottom: 20px;
  color: var(--text-light);
  position: relative;
  padding: 0 20px;
}

.quote::before, .quote::after {
  content: '"';
  font-size: 2rem;
  color: var(--primary-light);
  position: absolute;
}

.quote::before {
  left: 0;
  top: -10px;
}

.quote::after {
  right: 0;
  bottom: -20px;
}

.author {
  display: flex;
  align-items: center;
}

.author img {
  width: 50px;
  height: 50px;
  border-radius: 50%;
  object-fit: cover;
  margin-right: 15px;
}

.author h4 {
  font-size: 1rem;
  margin-bottom: 5px;
}

.author p {
  font-size: 0.9rem;
  color: var(--text-light);
}

.testimonial-controls {
  display: flex;
  justify-content: center;
  gap: 8px;
  margin-top: 30px;
}

.testimonial-controls span {
  display: inline-block;
  width: 12px;
  height: 12px;
  border-radius: 50%;
  background-color: var(--border-color);
  cursor: pointer;
}

.testimonial-controls span.active {
  background-color: var(--primary-color);
}

/* Contact Section */
.contact {
  padding: 80px 0;
  background-color: white;
}

.contact .container {
  display: flex;
  gap: 50px;
}

.contact-info, .contact-form {
  flex: 1;
}

.contact-info h2 {
  margin-bottom: 20px;
}

.contact-info p {
  margin-bottom: 30px;
  color: var(--text-light);
}

.contact-info ul {
  margin-bottom: 30px;
}

.contact-info li {
  margin-bottom: 15px;
  display: flex;
  align-items: center;
}

.contact-info li i {
  width: 30px;
  height: 30px;
  background-color: var(--primary-light);
  color: white;
  border-radius: 50%;
  display: flex;
  align-items: center;
  justify-content: center;
  margin-right: 15px;
}

.social-links {
  display: flex;
  gap: 15px;
}

.social-links a {
  width: 40px;
  height: 40px;
  background-color: var(--bg-light);
  color: var(--primary-color);
  border-radius: 50%;
  display: flex;
  align-items: center;
  justify-content: center;
  transition: var(--transition);
}

.social-links a:hover {
  background-color: var(--primary-color);
  color: white;
}

.contact-form h3 {
  margin-bottom: 20px;
}

.form-group {
  margin-bottom: 20px;
}

.form-group input, .form-group textarea {
  width: 100%;
  padding: 12px;
  border-radius: var(--border-radius);
  border: 1px solid var(--border-color);
  font-size: 1rem;
  transition: var(--transition);
}

.form-group input:focus, .form-group textarea:focus {
  outline: none;
  border-color: var(--primary-color);
}

/* Footer */
footer {
  background-color: #f8f9fa;
  padding-top: 60px;
}

.footer-content {
  display: flex;
  flex-wrap: wrap;
  justify-content: space-between;
  gap: 40px;
  padding-bottom: 40px;
}

.footer-logo {
  flex: 1 1 250px;
}

.footer-logo i {
  font-size: 2rem;
  color: var(--primary-color);
  margin-bottom: 10px;
}

.footer-logo h2 {
  font-size: 1.5rem;
  margin-bottom: 10px;
}

.footer-logo p {
  color: var(--text-light);
}

.footer-links {
  flex: 1 1 150px;
}

.footer-links h3 {
  font-size: 1.2rem;
  margin-bottom: 15px;
}

.footer-links ul li {
  margin-bottom: 10px;
}

.footer-newsletter {
  flex: 1 1 300px;
}

.footer-newsletter h3 {
  font-size: 1.2rem;
  margin-bottom: 15px;
}

.footer-newsletter p {
  margin-bottom: 15px;
  color: var(--text-light);
}

.footer-newsletter form {
  display: flex;
}

.footer-newsletter input {
  flex: 1;
  padding: 10px 15px;
  border: 1px solid var(--border-color);
  border-right: none;
  border-radius: var(--border-radius) 0 0 var(--border-radius);
}

.footer-newsletter button {
  border-radius: 0 var(--border-radius) var(--border-radius) 0;
}

.footer-bottom {
  padding: 20px 0;
  text-align: center;
  border-top: 1px solid var(--border-color);
}

/* Responsive Design */
@media (max-width: 992px) {
  .hero .container {
    flex-direction: column;
    gap: 40px;
    text-align: center;
  }

  .hero-image {
    max-width: 400px;
  }

  .cta-buttons {
    justify-content: center;
  }

  .contact .container {
    flex-direction: column;
  }
}

@media (max-width: 768px) {
  .hamburger {
    display: flex;
  }

  .nav-links {
    position: fixed;
    top: 70px;
    left: 0;
    right: 0;
    background-color: white;
    flex-direction: column;
    align-items: center;
    padding: 20px 0;
    height: 0;
    overflow: hidden;
    transition: var(--transition);
    box-shadow: 0 5px 10px rgba(0, 0, 0, 0.1);
    opacity: 0;
  }

  .nav-links.active {
    height: auto;
    opacity: 1;
    padding: 20px 0;
  }

  .nav-links li {
    margin: 10px 0;
  }

  .conversion-box {
    flex-direction: column;
  }

  .swap-btn {
    transform: rotate(90deg);
  }
}

@media (max-width: 576px) {
  .hero-content h1 {
    font-size: 2.5rem;
  }

  .section-title {
    font-size: 1.8rem;
  }

  .download-buttons {
    flex-direction: column;
    align-items: center;
  }
}