:root {
  --primary-color: #00c853;
  --secondary-color: #64dd17;
  --accent-color: #00e5ff;
  --text-color: #263238;
  --background-color: #f5f7fa;
  --gradient-1: linear-gradient(135deg, #00c853 0%, #64dd17 100%);
  --gradient-2: linear-gradient(135deg, #00e5ff 0%, #2979ff 100%);
  --card-shadow: 0 10px 20px rgba(0, 0, 0, 0.08);
  --hover-shadow: 0 15px 30px rgba(0, 0, 0, 0.12);
}

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

body {
  font-family: "Segoe UI", system-ui, -apple-system, sans-serif;
  line-height: 1.6;
  color: var(--text-color);
  background: var(--background-color);
  overflow-x: hidden;
}

/* Header and Navigation */
header {
  position: fixed;
  width: 100%;
  top: 0;
  z-index: 1000;
  background: rgba(255, 255, 255, 0.98);
  backdrop-filter: blur(10px);
  box-shadow: var(--card-shadow);
  transition: transform 0.3s ease;
}

header.scroll-down {
  transform: translateY(-100%);
}

header.scroll-up {
  transform: translateY(0);
  box-shadow: var(--card-shadow);
}

.logo {
  font-size: 1.8rem;
  font-weight: 700;
  background: var(--gradient-1);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  transition: transform 0.3s ease;
}

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

#main-nav {
  display: flex;
  justify-content: space-between;
  align-items: center;
  padding: 1rem 5%;
  max-width: 1400px;
  margin: 0 auto;
}

.nav-links {
  display: flex;
  gap: 2.5rem;
  list-style: none;
}

.nav-links a {
  text-decoration: none;
  color: var(--text-color);
  font-weight: 500;
  position: relative;
  padding: 0.5rem 0;
  transition: color 0.3s ease;
}

.nav-links a::after {
  content: "";
  position: absolute;
  bottom: 0;
  left: 0;
  width: 0;
  height: 2px;
  background: var(--gradient-1);
  transition: width 0.3s ease;
}

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

.nav-links a:hover::after {
  width: 100%;
}

/* Hero Section */
.hero-section {
  margin-top: 80px;
  padding: 6rem 5%;
  text-align: center;
  background: var(--gradient-2);
  position: relative;
  overflow: hidden;
}

.hero-section::before {
  content: "";
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  bottom: 0;
  background: url('data:image/svg+xml,<svg width="20" height="20" viewBox="0 0 20 20" xmlns="http://www.w3.org/2000/svg"><circle cx="2" cy="2" r="1" fill="rgba(255,255,255,0.1)"/></svg>');
  opacity: 0.3;
}

.hero-section h1 {
  font-size: 3.5rem;
  margin-bottom: 2rem;
  color: white;
  text-shadow: 0 2px 4px rgba(0, 0, 0, 0.1);
  animation: slideUp 1s ease-out;
}

.hero-content {
  position: relative;
  z-index: 1;
}

.hero-content img {
  max-width: 100%;
  height: auto;
  border-radius: 20px;
  box-shadow: var(--card-shadow);
  transition: transform 0.5s ease, box-shadow 0.5s ease;
  animation: fadeIn 1s ease-out;
}

.hero-content img:hover {
  transform: translateY(-10px);
  box-shadow: var(--hover-shadow);
}

.intro-text {
  font-size: 1.2rem;
  color: white;
  max-width: 800px;
  margin: 2rem auto;
  line-height: 1.8;
  animation: fadeIn 1.2s ease-out;
}

/* Content Sections */
.content-section {
  padding: 2rem 5%;
  max-width: 1400px;
  margin: 0 auto;
  position: relative;
  display: flex;
  flex-direction: column;
  align-items: center;
  width: 100%;
  overflow: hidden;
}

.section-content {
  width: 100%;
  max-width: 1400px;
  margin: 0 auto;
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 3rem;
}

/* Text Content */
.text-content {
  padding: 3rem;
  background: white;
  border-radius: 20px;
  box-shadow: var(--card-shadow);
  transition: transform 0.3s ease, box-shadow 0.3s ease;
  position: relative;
  overflow: hidden;
  backdrop-filter: blur(10px);
  width: 100%;
  max-width: 1200px;
  margin: 0 auto;
  display: flex;
  flex-direction: column;
  gap: 1.5rem;
}

.text-content::before {
  content: "";
  position: absolute;
  top: 0;
  left: 0;
  width: 100%;
  height: 5px;
  background: var(--gradient-1);
}

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

.text-content p {
  margin: 0;
  font-size: 1.1rem;
  line-height: 1.8;
  color: var(--text-color);
  text-align: justify;
  max-width: 1000px;
  margin-left: auto;
  margin-right: auto;
}

/* Section with Image */
.section-content.with-image {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 3rem;
  align-items: center;
}

.section-content.with-image .text-content {
  margin: 0;
}

.section-content img {
  width: 100%;
  max-width: 600px;
  height: auto;
  border-radius: 20px;
  box-shadow: var(--card-shadow);
  transition: all 0.5s ease;
  position: relative;
  margin: 0 auto;
}

.section-content img:hover {
  transform: scale(1.03) rotate(1deg);
  box-shadow: var(--hover-shadow);
}

/* Section Headers */
.content-section h2 {
  font-size: 2.5rem;
  color: var(--text-color);
  margin-bottom: 3rem;
  text-align: center;
  position: relative;
  background: var(--gradient-1);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  display: inline-block;
}

.content-section h2::after {
  content: "";
  display: block;
  width: 80px;
  height: 4px;
  background: var(--gradient-1);
  margin: 1rem auto;
  border-radius: 2px;
}

.content-section h2::before {
  content: "";
  position: absolute;
  width: 120%;
  height: 100%;
  background: radial-gradient(
    circle,
    rgba(0, 200, 83, 0.1) 0%,
    rgba(255, 255, 255, 0) 70%
  );
  top: 50%;
  left: 50%;
  transform: translate(-50%, -50%);
  z-index: -1;
}

/* Sustainability Tool */
.sustainability-tool {
  background: white;
  padding: 3rem;
  border-radius: 20px;
  box-shadow: var(--card-shadow);
  margin: 4rem auto;
  position: relative;
  overflow: hidden;
  max-width: 1000px;
}

.sustainability-tool h3 {
  font-size: 2rem;
  color: var(--text-color);
  text-align: center;
  margin-bottom: 2rem;
  background: var(--gradient-1);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
}

.checklist-widget {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
  gap: 2rem;
  position: relative;
}

.checklist-category {
  background: rgba(255, 255, 255, 0.9);
  padding: 2rem;
  border-radius: 15px;
  box-shadow: 0 5px 15px rgba(0, 0, 0, 0.05);
  transition: transform 0.3s ease;
}

.checklist-category:hover {
  transform: translateY(-5px);
}

.checklist-category h4 {
  font-size: 1.3rem;
  color: var(--text-color);
  margin-bottom: 1.5rem;
  padding-bottom: 0.5rem;
  border-bottom: 3px solid var(--primary-color);
  display: inline-block;
}

.checklist-item {
  margin-bottom: 1rem;
  display: flex;
  align-items: center;
  gap: 1rem;
}

.checklist-item input[type="checkbox"] {
  appearance: none;
  -webkit-appearance: none;
  width: 24px;
  height: 24px;
  border: 2px solid var(--primary-color);
  border-radius: 6px;
  cursor: pointer;
  position: relative;
  transition: all 0.3s ease;
}

.checklist-item input[type="checkbox"]:checked {
  background: var(--gradient-1);
  border-color: transparent;
}

.checklist-item input[type="checkbox"]:checked::before {
  content: "✓";
  position: absolute;
  color: white;
  font-size: 16px;
  font-weight: bold;
  left: 50%;
  top: 50%;
  transform: translate(-50%, -50%);
}

.checklist-item label {
  font-size: 1.1rem;
  color: var(--text-color);
  cursor: pointer;
  user-select: none;
}

.checklist-result {
  grid-column: 1 / -1;
  text-align: center;
  padding: 2rem;
  background: var(--gradient-2);
  border-radius: 15px;
  color: white;
  margin-top: 1rem;
}

.checklist-result p {
  font-size: 1.2rem;
  margin-bottom: 0.5rem;
}

.checklist-result #score {
  font-size: 1.5rem;
  font-weight: bold;
}

.score-message {
  font-size: 1.1rem;
  opacity: 0.9;
}

/* Checklist Animations */
@keyframes checkmark {
  0% {
    transform: scale(0);
  }
  50% {
    transform: scale(1.2);
  }
  100% {
    transform: scale(1);
  }
}

.checklist-item input[type="checkbox"]:checked::before {
  animation: checkmark 0.3s ease-out;
}

@media (max-width: 768px) {
  .sustainability-tool {
    padding: 2rem;
    margin: 2rem 1rem;
  }

  .checklist-category {
    padding: 1.5rem;
  }

  .checklist-item label {
    font-size: 1rem;
  }

  .content-section {
    padding: 3rem 0;
  }

  .text-content {
    padding: 1.5rem;
    width: 92%;
    margin: 0 auto;
    gap: 1.2rem;
  }

  .text-content p {
    font-size: 1rem;
    line-height: 1.7;
  }
}

@media (max-width: 480px) {
  .hero-section h1,
  .content-section h2 {
    font-size: 1.8rem;
  }

  .content-section {
    padding: 2rem 0;
  }

  .text-content {
    padding: 1rem;
    gap: 1rem;
  }

  .text-content p {
    font-size: 0.95rem;
    line-height: 1.6;
  }
}

/* Footer Styles */
footer {
  background: var(--text-color);
  color: white;
  padding: 4rem 5%;
  position: relative;
  overflow: hidden;
}

footer::before {
  content: "";
  position: absolute;
  top: 0;
  left: 0;
  width: 100%;
  height: 5px;
  background: var(--gradient-1);
}

.footer-content {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
  gap: 3rem;
  max-width: 1200px;
  margin: 0 auto;
}

.footer-section h4 {
  font-size: 1.5rem;
  margin-bottom: 1.5rem;
  position: relative;
  display: inline-block;
}

.footer-section h4::after {
  content: "";
  position: absolute;
  bottom: -5px;
  left: 0;
  width: 40px;
  height: 3px;
  background: var(--gradient-1);
}

.footer-section ul {
  list-style: none;
}

.footer-section a {
  color: white;
  text-decoration: none;
  opacity: 0.8;
  transition: all 0.3s ease;
  display: inline-block;
}

.footer-section a:hover {
  opacity: 1;
  transform: translateX(5px);
}

.copyright {
  text-align: center;
  margin-top: 3rem;
  padding-top: 2rem;
  border-top: 1px solid rgba(255, 255, 255, 0.1);
  font-size: 0.9rem;
  opacity: 0.8;
}

/* Scroll Progress Bar */
.scroll-progress {
  position: fixed;
  top: 0;
  left: 0;
  width: 100%;
  height: 3px;
  background: rgba(255, 255, 255, 0.1);
  z-index: 1001;
}

.scroll-progress-bar {
  height: 100%;
  background: var(--gradient-1);
  width: 0;
  transition: width 0.1s ease;
}

/* Image Hover Effects */
.section-content img::after {
  content: "";
  position: absolute;
  inset: 0;
  background: var(--gradient-1);
  opacity: 0;
  transition: opacity 0.3s ease;
  border-radius: 20px;
}

.section-content img:hover::after {
  opacity: 0.1;
}

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

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

/* Responsive Design */
@media (max-width: 1200px) {
  .content-section {
    padding: 4rem 3%;
  }

  .text-content {
    padding: 2.5rem;
  }
}

@media (max-width: 768px) {
  /* Header */
  header {
    padding: 0.5rem 0;
  }

  #main-nav {
    padding: 0.5rem 1rem;
    position: relative;
  }

  /* Мобильное меню */
  .mobile-menu-toggle {
    display: flex;
    flex-direction: column;
    justify-content: space-between;
    width: 30px;
    height: 20px;
    background: transparent;
    border: none;
    cursor: pointer;
    padding: 0;
    z-index: 1001;
    position: relative;
  }

  .mobile-menu-toggle span {
    display: block;
    width: 100%;
    height: 2px;
    background-color: var(--text-color);
    transition: all 0.3s ease;
  }

  .mobile-menu-toggle.active {
    span:nth-child(1) {
      transform: translateY(8px) rotate(45deg);
    }
    span:nth-child(2) {
      opacity: 0;
    }
    span:nth-child(3) {
      transform: translateY(-8px) rotate(-45deg);
    }
  }

  /* Навигация */
  .nav-links {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100vh;
    background: rgba(255, 255, 255, 0.98);
    backdrop-filter: blur(10px);
    display: flex;
    flex-direction: column;
    justify-content: center;
    align-items: center;
    gap: 2rem;
    opacity: 0;
    visibility: hidden;
    transform: translateX(-100%);
    transition: all 0.3s ease-in-out;
    padding: 5rem 2rem;

    &.active {
      opacity: 1;
      visibility: visible;
      transform: translateX(0);

      li {
        opacity: 1;
        transform: translateY(0);
      }
    }

    li {
      opacity: 0;
      transform: translateY(20px);
      transition: all 0.3s ease;
      transition-delay: calc(0.1s * var(--i));
    }
  }

  /* Контент */
  .text-content {
    padding: 1.5rem;
    width: 92%;
    margin: 0 auto;
  }

  .section-content {
    &.with-image {
      grid-template-columns: 1fr;
      gap: 2rem;
      width: 100%;
    }

    img {
      width: 92%;
      margin: 0 auto;
    }
  }

  .content-section {
    padding: 3rem 0;
  }

  /* Hero секция */
  .hero-section {
    padding: 4rem 1rem;
    margin-top: 60px;

    h1 {
      font-size: 2rem;
      padding: 0 1rem;
    }
  }

  /* Чеклист */
  .checklist-widget {
    grid-template-columns: 1fr;
    width: 92%;
    margin: 0 auto;
  }

  .sustainability-tool {
    margin: 2rem 1rem;
    padding: 1.5rem;
  }
}