:root {
  --font-primary: "Inter", -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto,
    Helvetica, Arial, sans-serif;
  --font-secondary: "Lora", serif;

  /* Light Theme */
  --color-bg: #f8f9fa;
  --color-text-primary: #212529;
  --color-text-secondary: #495057;
  --color-accent: #005a9c;
  --color-accent-hover: #004578;
  --color-card-bg: #ffffff;
  --color-border: #dee2e6;
  --color-input-bg: #ffffff;
  --color-input-border: #ced4da;
  --color-success: #198754;
  --color-shadow: rgba(0, 0, 0, 0.05);

  /* Spacing & Sizing */
  --spacing-xs: 4px;
  --spacing-sm: 8px;
  --spacing-md: 16px;
  --spacing-lg: 32px;
  --spacing-xl: 64px;
  --spacing-xxl: 128px;
  --border-radius-sm: 4px;
  --border-radius-md: 8px;
  --border-radius-lg: 16px;
  --container-width: 1240px;
  --transition-speed: 0.3s;
}

@media (prefers-color-scheme: dark) {
  :root {
    --color-bg: #121212;
    --color-text-primary: #eaeaea;
    --color-text-secondary: #a0a0a0;
    --color-accent: #4d96ff;
    --color-accent-hover: #73b0ff;
    --color-card-bg: #1e1e1e;
    --color-border: #333333;
    --color-input-bg: #2c2c2c;
    --color-input-border: #444444;
    --color-success: #28a745;
    --color-shadow: rgba(0, 0, 0, 0.2);
  }
}

/* 1. Base & Reset */
*,
*::before,
*::after {
  box-sizing: border-box;
  margin: 0;
  padding: 0;
}

html {
  font-size: 16px;
  scroll-behavior: smooth;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
}

body {
  font-family: var(--font-primary);
  background-color: var(--color-bg);
  color: var(--color-text-primary);
  line-height: 1.7;
  overflow-x: hidden;
}

img,
picture,
video,
canvas,
svg {
  display: block;
  max-width: 100%;
}

input,
button,
textarea,
select {
  font: inherit;
}

a {
  color: var(--color-accent);
  text-decoration: none;
  transition: color var(--transition-speed) ease;
}

a:hover {
  color: var(--color-accent-hover);
  text-decoration: underline;
}

/* 2. Typography */
h1,
h2,
h3,
h4,
h5,
h6 {
  font-family: var(--font-secondary);
  font-weight: 700;
  line-height: 1.2;
  color: var(--color-text-primary);
  text-wrap: balance;
}

h1 {
  font-size: clamp(2.5rem, 5vw, 4rem);
  margin-bottom: var(--spacing-md);
}

h2 {
  font-size: clamp(2rem, 4vw, 3rem);
  margin-bottom: var(--spacing-sm);
}

h3 {
  font-size: clamp(1.5rem, 3vw, 2rem);
  margin-bottom: var(--spacing-sm);
}

h4 {
  font-size: clamp(1.1rem, 2vw, 1.25rem);
  font-family: var(--font-primary);
  font-weight: 600;
}

p {
  margin-bottom: var(--spacing-md);
  max-width: 75ch;
  color: var(--color-text-secondary);
}

p.subtitle {
  font-size: clamp(1rem, 2vw, 1.25rem);
  color: var(--color-text-secondary);
}

ul,
ol {
  padding-left: var(--spacing-md);
}

strong {
  font-weight: 600;
  color: var(--color-text-primary);
}

/* 3. Layout */
.container {
  width: 100%;
  max-width: var(--container-width);
  margin-left: auto;
  margin-right: auto;
  padding-left: var(--spacing-lg);
  padding-right: var(--spacing-lg);
}

section {
  padding-top: var(--spacing-xl);
  padding-bottom: var(--spacing-xl);
}

.section-header {
  text-align: center;
  max-width: 800px;
  margin: 0 auto var(--spacing-lg) auto;
}

.grid-container {
  display: grid;
  gap: var(--spacing-lg);
}

/* 4. Buttons */
.button-primary,
.button-secondary,
.button-large {
  display: inline-block;
  padding: var(--spacing-sm) var(--spacing-lg);
  font-weight: 600;
  border-radius: var(--border-radius-md);
  border: 2px solid transparent;
  cursor: pointer;
  text-align: center;
  transition: all var(--transition-speed) ease;
  text-decoration: none;
}

.button-primary {
  background-color: var(--color-accent);
  color: #fff;
}

.button-primary:hover {
  background-color: var(--color-accent-hover);
  color: #fff;
  transform: translateY(-3px);
  box-shadow: 0 4px 15px rgba(0, 90, 156, 0.2);
  text-decoration: none;
}

.button-secondary {
  background-color: var(--color-card-bg);
  color: var(--color-accent);
  border-color: var(--color-border);
}

.button-secondary:hover {
  background-color: var(--color-bg);
  border-color: var(--color-accent);
  color: var(--color-accent);
  text-decoration: none;
}

.button-large {
  padding: var(--spacing-md) var(--spacing-xl);
  font-size: 1.1rem;
  border-radius: var(--border-radius-lg);
}

/* 5. Header & Navigation */
.main-header {
  padding: var(--spacing-md) 0;
  position: sticky;
  top: 0;
  z-index: 100;
  background-color: color-mix(in srgb, var(--color-bg) 80%, transparent);
  backdrop-filter: blur(10px);
  -webkit-backdrop-filter: blur(10px);
  border-bottom: 1px solid var(--color-border);
}

.main-nav {
  display: flex;
  justify-content: space-between;
  align-items: center;
}

.logo {
  display: flex;
  align-items: center;
  gap: var(--spacing-sm);
  font-size: 1.5rem;
  font-weight: 700;
  color: var(--color-text-primary);
  text-decoration: none;
}

.logo:hover {
  color: var(--color-accent);
  text-decoration: none;
}

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

.nav-links {
  display: flex;
  list-style: none;
  gap: var(--spacing-lg);
  padding: 0;
}

.nav-links a {
  color: var(--color-text-secondary);
  font-weight: 500;
  padding: var(--spacing-sm) 0;
  position: relative;
  text-decoration: none;
}

.nav-links a::after {
  content: "";
  position: absolute;
  bottom: 0;
  left: 0;
  width: 0;
  height: 2px;
  background-color: var(--color-accent);
  transition: width var(--transition-speed) ease;
}

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

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

/* 6. Hero Section */
.hero-section {
  padding-top: var(--spacing-xl);
  padding-bottom: var(--spacing-xxl);
}

.hero-section .container {
  display: grid;
  grid-template-columns: 1fr 1fr;
  align-items: center;
  gap: var(--spacing-xl);
}

.hero-content {
  animation: slide-in-left 1s ease-out forwards;
}

.hero-image-container {
  display: flex;
  justify-content: center;
  align-items: center;
  animation: fade-in 1.2s ease-out forwards;
}

.hero-image-container img {
  max-width: 500px;
  width: 100%;
  border-radius: var(--border-radius-lg);
  object-fit: cover;
}

@keyframes slide-in-left {
  from {
    opacity: 0;
    transform: translateX(-50px);
  }
  to {
    opacity: 1;
    transform: translateX(0);
  }
}

@keyframes fade-in {
  from {
    opacity: 0;
  }
  to {
    opacity: 1;
  }
}

/* 7. Weekly Progress Section */
.weekly-progress-section {
  background-color: var(--color-card-bg);
  border-top: 1px solid var(--color-border);
  border-bottom: 1px solid var(--color-border);
}

.progress-card {
  max-width: 800px;
  margin: 0 auto;
  padding: var(--spacing-xl);
  background-color: var(--color-bg);
  border-radius: var(--border-radius-lg);
  box-shadow: 0 10px 30px var(--color-shadow);
  text-align: center;
}

.progress-icon {
  margin: 0 auto var(--spacing-lg) auto;
  width: 60px;
  height: 60px;
  background-color: color-mix(in srgb, var(--color-accent) 15%, transparent);
  border-radius: 50%;
  display: flex;
  justify-content: center;
  align-items: center;
}

.progress-icon svg {
  stroke: var(--color-accent);
  width: 32px;
  height: 32px;
}

#weekly-progress-form .input-group {
  text-align: left;
  margin-bottom: var(--spacing-md);
}

#weekly-progress-form label {
  display: block;
  margin-bottom: var(--spacing-sm);
  font-weight: 500;
  color: var(--color-text-secondary);
}

#weekly-progress-form input[type="text"] {
  width: 100%;
  padding: var(--spacing-md);
  background-color: var(--color-input-bg);
  border: 1px solid var(--color-input-border);
  border-radius: var(--border-radius-md);
  color: var(--color-text-primary);
  transition: border-color var(--transition-speed) ease,
    box-shadow var(--transition-speed) ease;
}

#weekly-progress-form input[type="text"]:focus {
  outline: none;
  border-color: var(--color-accent);
  box-shadow: 0 0 0 3px color-mix(in srgb, var(--color-accent) 20%, transparent);
}

#weekly-progress-form .button-secondary {
  margin-top: var(--spacing-md);
  width: 100%;
}

.thank-you-message {
  margin-top: var(--spacing-lg);
  padding: var(--spacing-md);
  background-color: color-mix(in srgb, var(--color-success) 10%, transparent);
  border: 1px solid color-mix(in srgb, var(--color-success) 30%, transparent);
  border-radius: var(--border-radius-md);
  color: var(--color-success);
}

.thank-you-message p {
  margin-bottom: 0;
  color: var(--color-success);
}

/* 8. Why It Works Section */
.features-grid {
  grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
}

.feature-card {
  background-color: var(--color-card-bg);
  padding: var(--spacing-lg);
  border-radius: var(--border-radius-lg);
  border: 1px solid var(--color-border);
  transition: transform var(--transition-speed) ease,
    box-shadow var(--transition-speed) ease;
}

.feature-card:hover {
  transform: translateY(-5px);
  box-shadow: 0 15px 35px var(--color-shadow);
}

.feature-icon {
  margin-bottom: var(--spacing-md);
  color: var(--color-accent);
}

.feature-icon svg {
  width: 36px;
  height: 36px;
  stroke-width: 1.5;
}

/* 9. Stories Section */
.stories-section {
  background-color: var(--color-card-bg);
  border-top: 1px solid var(--color-border);
  border-bottom: 1px solid var(--color-border);
}

.stories-wrapper {
  display: grid;
  gap: var(--spacing-lg);
}

.story-card {
  background-color: var(--color-bg);
  padding: var(--spacing-lg);
  border-radius: var(--border-radius-md);
  border-left: 4px solid var(--color-accent);
}

.story-card h3 {
  font-family: var(--font-primary);
  font-size: 1.25rem;
}

.story-card p:last-of-type {
  margin-bottom: 0;
}

.story-card strong {
  color: var(--color-text-primary);
  font-weight: 600;
}

/* 10. Guide Section (Accordion) */
.guide-main-icon {
  max-width: 80px;
  margin: 0 auto var(--spacing-md) auto;
  filter: var(--color-bg) invert(10%) sepia(100%);
}

.accordion {
  max-width: 900px;
  margin: 0 auto;
  display: flex;
  flex-direction: column;
  gap: var(--spacing-md);
}

.accordion-item {
  background-color: var(--color-card-bg);
  border: 1px solid var(--color-border);
  border-radius: var(--border-radius-md);
  transition: background-color var(--transition-speed) ease;
}

.accordion-item[open] {
  background-color: var(--color-bg);
}

.accordion-header {
  display: flex;
  justify-content: space-between;
  align-items: center;
  padding: var(--spacing-md) var(--spacing-lg);
  cursor: pointer;
  list-style: none;
}

.accordion-header::-webkit-details-marker {
  display: none;
}

.accordion-header h4 {
  margin: 0;
  color: var(--color-text-primary);
}

.accordion-icon {
  color: var(--color-text-secondary);
  transition: transform var(--transition-speed) ease;
}

.accordion-item[open] .accordion-icon {
  transform: rotate(180deg);
  color: var(--color-accent);
}

.accordion-content {
  padding: 0 var(--spacing-lg) var(--spacing-lg) var(--spacing-lg);
}

.accordion-content ol {
  padding-left: var(--spacing-lg);
  display: flex;
  flex-direction: column;
  gap: var(--spacing-md);
}

.accordion-content li {
  color: var(--color-text-secondary);
  padding-left: var(--spacing-sm);
}

.accordion-content li::marker {
  color: var(--color-accent);
  font-weight: 600;
}

/* 11. Final CTA Section */
.final-cta-section {
  background-color: var(--color-accent);
  color: #fff;
  text-align: center;
  padding: var(--spacing-xxl) 0;
}

.final-cta-section .cta-content {
  max-width: 800px;
  margin: 0 auto;
}

.final-cta-section h2,
.final-cta-section p {
  color: #fff;
}

.final-cta-section .button-primary {
  background-color: #fff;
  color: var(--color-accent);
  border-color: #fff;
}

.final-cta-section .button-primary:hover {
  background-color: transparent;
  color: #fff;
  border-color: #fff;
}

.cta-image {
  max-width: 150px;
  margin: 0 auto var(--spacing-lg) auto;
  border-radius: 50%;
  border: 4px solid #fff;
  box-shadow: 0 0 20px rgba(255, 255, 255, 0.3);
}

/* 12. Footer */
.main-footer-section {
  background-color: var(--color-card-bg);
  border-top: 1px solid var(--color-border);
  padding-top: var(--spacing-xl);
  padding-bottom: var(--spacing-lg);
  color: var(--color-text-secondary);
  font-size: 0.9rem;
}

.footer-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(220px, 1fr));
  gap: var(--spacing-xl);
  margin-bottom: var(--spacing-xl);
}

.footer-column h4 {
  font-family: var(--font-primary);
  font-size: 1rem;
  font-weight: 600;
  color: var(--color-text-primary);
  margin-bottom: var(--spacing-md);
}

.footer-column ul {
  list-style: none;
  padding: 0;
  display: flex;
  flex-direction: column;
  gap: var(--spacing-sm);
}

.footer-column a {
  color: var(--color-text-secondary);
}

.footer-column a:hover {
  color: var(--color-accent);
  text-decoration: none;
}

.footer-column address {
  font-style: normal;
  line-height: 1.6;
}

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

/* 13. Cookie Banner */
.cookie-banner {
  position: fixed;
  bottom: 0;
  left: 0;
  right: 0;
  background-color: var(--color-card-bg);
  box-shadow: 0 -5px 20px var(--color-shadow);
  padding: var(--spacing-md) 0;
  z-index: 1000;
  transform: translateY(100%);
  transition: transform 0.5s ease-in-out;
  border-top: 1px solid var(--color-border);
}

.cookie-banner.visible {
  transform: translateY(0);
}

.cookie-banner-content {
  display: flex;
  justify-content: space-between;
  align-items: center;
  gap: var(--spacing-lg);
}

.cookie-banner p {
  margin: 0;
  color: var(--color-text-secondary);
}

.cookie-banner .button-secondary {
  flex-shrink: 0;
}

/* 14. Scroll Animations */
.fade-in-element {
  opacity: 0;
  transform: translateY(30px);
  transition: opacity 0.8s ease-out, transform 0.8s ease-out;
}

.fade-in-element.is-visible {
  opacity: 1;
  transform: translateY(0);
}

/* 15. Responsive Design */
@media (max-width: 992px) {
  .hero-section .container {
    grid-template-columns: 1fr;
    text-align: center;
  }

  .hero-image-container {
    order: -1;
    margin-bottom: var(--spacing-lg);
  }
}

@media (max-width: 768px) {
  body {
    --spacing-xl: 48px;
    --spacing-lg: 24px;
    --spacing-md: 12px;
  }

  h1 {
    font-size: 2.2rem;
  }
  h2 {
    font-size: 1.8rem;
  }

  .main-nav .button-primary {
    display: none;
  }

  .nav-links {
    position: fixed;
    top: 0;
    right: 0;
    width: 300px;
    height: 100vh;
    background-color: var(--color-card-bg);
    flex-direction: column;
    padding: var(--spacing-xl) var(--spacing-lg);
    transform: translateX(100%);
    transition: transform var(--transition-speed) ease-in-out;
    box-shadow: -10px 0 30px var(--color-shadow);
    z-index: 998;
  }

  .nav-links.nav-active {
    transform: translateX(0);
  }

  .nav-toggle {
    display: block;
    z-index: 999;
  }

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

  .about-column {
    grid-column: 1 / -1;
  }
}

@media (max-width: 576px) {
  .container {
    padding-left: var(--spacing-md);
    padding-right: var(--spacing-md);
  }

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

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

  .cookie-banner-content {
    flex-direction: column;
    gap: var(--spacing-md);
    text-align: center;
  }
}