@import url('https://fonts.googleapis.com/css2?family=Nunito+Sans:wght@300;600;800&display=swap');

:root {
  /* Colors */
  --color-dark-elements: hsl(209, 23%, 22%);
  --color-dark-background: hsl(207, 26%, 17%);
  --color-dark-text: hsl(0, 100%, 100%);
  
  --color-light-background: hsl(0, 0%, 99%);
  --color-light-elements: hsl(0, 100%, 100%);
  --color-light-text: hsl(200, 15%, 8%);
  --color-light-input: hsl(0, 0%, 50%);
  
  /* Typography */
  --font-family: 'Nunito Sans', sans-serif;
  
  --font-weight-light: 300;
  --font-weight-semibold: 600;
  --font-weight-extra-bold: 800;
  
  --font-size-homepage: 14px;
  --font-size-detail: 16px;
  --font-size-base: 16px;
  --font-size-lg: 18px;
  --font-size-xl: 24px;
  --font-size-2xl: 32px;
  
  /* Layout */
  --width-mobile: 375px;
  --width-desktop: 1440px;
  
  --breakpoint-mobile-min: 320px;
  --breakpoint-mobile: 375px;
  --breakpoint-tablet: 768px;
  --breakpoint-desktop: 1024px;
  --breakpoint-desktop-large: 1440px;
  
  /* Spacing */
  --spacing-xs: 0.25rem;
  --spacing-sm: 0.5rem;
  --spacing-md: 1rem;
  --spacing-lg: 1.5rem;
  --spacing-xl: 2rem;
  --spacing-2xl: 3rem;
  --spacing-3xl: 4rem;
  
  --container-mobile: 100%;
  --container-tablet: 768px;
  --container-desktop: 1200px;
  --container-max: 1440px;
  
  /* Effects */
  --shadow-light: 0 2px 8px rgba(0, 0, 0, 0.1);
  --shadow-medium: 0 4px 16px rgba(0, 0, 0, 0.15);
  --shadow-dark: 0 2px 8px rgba(0, 0, 0, 0.3);
  
  /* Border Radius */
  --border-radius-sm: 4px;
  --border-radius-md: 8px;
  --border-radius-lg: 12px;
  
  --transition-fast: 0.15s ease-in-out;
  --transition-normal: 0.3s ease-in-out;
  --transition-slow: 0.5s ease-in-out;
}

/* Light Theme (Default) */
.theme-light {
  --background-color: var(--color-light-background);
  --elements-color: var(--color-light-elements);
  --text-color: var(--color-light-text);
  --input-color: var(--color-light-input);
  --shadow: var(--shadow-light);
}

/* Dark Theme */
.theme-dark {
  --background-color: var(--color-dark-background);
  --elements-color: var(--color-dark-elements);
  --text-color: var(--color-dark-text);
  --input-color: var(--color-light-input);
  --shadow: var(--shadow-dark);
}

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

body {
  font-family: var(--font-family);
  font-weight: var(--font-weight-light);
  background-color: var(--background-color);
  color: var(--text-color);
  transition: background-color var(--transition-normal), color var(--transition-normal);
  line-height: 1.6;
}

h1, h2, h3, h4, h5, h6 {
  font-weight: var(--font-weight-extra-bold);
  line-height: 1.2;
}

.container {
  width: 100%;
  max-width: var(--container-max);
  margin: 0 auto;
  padding: 0 var(--spacing-md);
}

@media (min-width: 768px) {
  .container {
    padding: 0 var(--spacing-xl);
  }
}

.header {
  background-color: var(--elements-color);
  box-shadow: var(--shadow);
  position: sticky;
  top: 0;
  z-index: 100;
  transition: background-color var(--transition-normal), box-shadow var(--transition-normal);
}

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

.header-title {
  font-size: var(--font-size-lg);
  font-weight: var(--font-weight-extra-bold);
  color: var(--text-color);
}

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

/* Theme Toggle */
.theme-toggle {
  display: flex;
  align-items: center;
  gap: var(--spacing-sm);
  background: none;
  border: none;
  color: var(--text-color);
  font-family: inherit;
  font-weight: var(--font-weight-semibold);
  cursor: pointer;
  padding: var(--spacing-sm);
  border-radius: var(--border-radius-sm);
  transition: all var(--transition-fast);
  font-size: var(--font-size-homepage);
}

.theme-toggle:hover {
  opacity: 0.7;
}

.theme-toggle:focus {
  outline: 2px solid var(--text-color);
  outline-offset: 2px;
}


.main {
  padding: var(--spacing-xl) 0;
  min-height: calc(100vh - 80px);
}


.filters {
  display: flex;
  flex-direction: column;
  gap: var(--spacing-lg);
  margin-bottom: var(--spacing-3xl);
}

@media (min-width: 768px) {
  .filters {
    flex-direction: row;
    justify-content: space-between;
    align-items: center;
  }
}

/* Search Container */
.search-container {
  flex: 1;
  max-width: 400px;
}

.search-input-wrapper {
  position: relative;
  background-color: var(--elements-color);
  border-radius: var(--border-radius-md);
  box-shadow: var(--shadow);
  transition: all var(--transition-normal);
}

.search-icon {
  position: absolute;
  left: var(--spacing-lg);
  top: 50%;
  transform: translateY(-50%);
  color: var(--input-color);
  font-size: var(--font-size-homepage);
}

.search-input {
  width: 100%;
  padding: var(--spacing-md) var(--spacing-lg) var(--spacing-md) 3.5rem;
  border: none;
  background: transparent;
  color: var(--text-color);
  font-family: inherit;
  font-size: var(--font-size-homepage);
  border-radius: var(--border-radius-md);
  outline: none;
}

.search-input::placeholder {
  color: var(--input-color);
}

.search-input:focus {
  box-shadow: var(--shadow), 0 0 0 2px var(--text-color);
}

/* Filter Container */
.filter-container {
  min-width: 200px;
}

/* Dropdown */
.dropdown {
  position: relative;
}

.dropdown-toggle {
  display: flex;
  justify-content: space-between;
  align-items: center;
  width: 100%;
  padding: var(--spacing-md) var(--spacing-lg);
  background-color: var(--elements-color);
  border: none;
  border-radius: var(--border-radius-md);
  color: var(--text-color);
  font-family: inherit;
  font-size: var(--font-size-homepage);
  cursor: pointer;
  box-shadow: var(--shadow);
  transition: all var(--transition-normal);
}

.dropdown-toggle:hover {
  box-shadow: var(--shadow-medium);
}

.dropdown-toggle:focus {
  outline: 2px solid var(--text-color);
  outline-offset: 2px;
}

.dropdown-icon {
  transition: transform var(--transition-fast);
}

.dropdown[aria-expanded="true"] .dropdown-icon {
  transform: rotate(180deg);
}

.dropdown-menu {
  position: absolute;
  top: calc(100% + var(--spacing-sm));
  left: 0;
  right: 0;
  background-color: var(--elements-color);
  border-radius: var(--border-radius-md);
  box-shadow: var(--shadow-medium);
  list-style: none;
  padding: var(--spacing-sm) 0;
  z-index: 10;
  opacity: 0;
  visibility: hidden;
  transform: translateY(-10px);
  transition: all var(--transition-fast);
}

.dropdown[aria-expanded="true"] .dropdown-menu {
  opacity: 1;
  visibility: visible;
  transform: translateY(0);
}

.dropdown-item {
  display: block;
  width: 100%;
  padding: var(--spacing-sm) var(--spacing-lg);
  background: none;
  border: none;
  color: var(--text-color);
  font-family: inherit;
  font-size: var(--font-size-homepage);
  text-align: left;
  cursor: pointer;
  transition: background-color var(--transition-fast);
}

.dropdown-item:hover {
  background-color: rgba(0, 0, 0, 0.1);
}

.dropdown-item:focus {
  background-color: rgba(0, 0, 0, 0.1);
  outline: none;
}

.loading, .error, .no-results {
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  text-align: center;
  padding: var(--spacing-3xl) var(--spacing-md);
  color: var(--text-color);
}

.loading-spinner {
  width: 40px;
  height: 40px;
  border: 3px solid var(--elements-color);
  border-top: 3px solid var(--text-color);
  border-radius: 50%;
  animation: spin 1s linear infinite;
  margin-bottom: var(--spacing-lg);
}

@keyframes spin {
  0% { transform: rotate(0deg); }
  100% { transform: rotate(360deg); }
}

.error-icon, .no-results-icon {
  font-size: var(--font-size-2xl);
  margin-bottom: var(--spacing-lg);
  color: var(--input-color);
}

.error h2, .no-results h2 {
  margin-bottom: var(--spacing-md);
  font-size: var(--font-size-xl);
}

.error p, .no-results p {
  margin-bottom: var(--spacing-lg);
  color: var(--input-color);
}


.btn {
  display: inline-flex;
  align-items: center;
  gap: var(--spacing-sm);
  padding: var(--spacing-sm) var(--spacing-lg);
  border: none;
  border-radius: var(--border-radius-sm);
  font-family: inherit;
  font-size: var(--font-size-homepage);
  font-weight: var(--font-weight-semibold);
  cursor: pointer;
  text-decoration: none;
  transition: all var(--transition-fast);
  box-shadow: var(--shadow);
}

.btn:focus {
  outline: 2px solid var(--text-color);
  outline-offset: 2px;
}

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

.btn-primary:hover {
  box-shadow: var(--shadow-medium);
  transform: translateY(-1px);
}

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

.btn-secondary:hover {
  box-shadow: var(--shadow-medium);
}

.countries-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(280px, 1fr));
  gap: var(--spacing-xl);
  margin-top: var(--spacing-xl);
}

@media (min-width: 768px) {
  .countries-grid {
    grid-template-columns: repeat(auto-fill, minmax(320px, 1fr));
    gap: var(--spacing-2xl);
  }
}

/* Country Card */
.country-card {
  background-color: var(--elements-color);
  border-radius: var(--border-radius-md);
  box-shadow: var(--shadow);
  overflow: hidden;
  cursor: pointer;
  transition: all var(--transition-normal);
  text-decoration: none;
  color: inherit;
}

.country-card:hover {
  transform: translateY(-8px);
  box-shadow: var(--shadow-medium);
}

.country-card:focus {
  outline: 2px solid var(--text-color);
  outline-offset: 4px;
}

.country-flag {
  width: 100%;
  height: 200px;
  object-fit: cover;
  border-bottom: 1px solid rgba(0, 0, 0, 0.1);
}

.country-info {
  padding: var(--spacing-lg);
}

.country-name {
  font-size: var(--font-size-lg);
  font-weight: var(--font-weight-extra-bold);
  margin-bottom: var(--spacing-md);
  color: var(--text-color);
}

.country-details {
  display: flex;
  flex-direction: column;
  gap: var(--spacing-xs);
}

.country-detail {
  font-size: var(--font-size-homepage);
  color: var(--text-color);
}

.country-detail strong {
  font-weight: var(--font-weight-semibold);
}

.modal {
  position: fixed;
  top: 0;
  left: 0;
  width: 100%;
  height: 100%;
  z-index: 1000;
  display: flex;
  align-items: center;
  justify-content: center;
  opacity: 0;
  visibility: hidden;
  transition: all var(--transition-normal);
}

.modal.show {
  opacity: 1;
  visibility: visible;
}

.modal-backdrop {
  position: absolute;
  top: 0;
  left: 0;
  width: 100%;
  height: 100%;
  background-color: rgba(0, 0, 0, 0.5);
  cursor: pointer;
}

.modal-content {
  position: relative;
  background-color: var(--background-color);
  border-radius: var(--border-radius-lg);
  box-shadow: var(--shadow-medium);
  max-width: 90vw;
  max-height: 90vh;
  overflow-y: auto;
  z-index: 1001;
  transform: scale(0.9);
  transition: transform var(--transition-normal);
}

.modal.show .modal-content {
  transform: scale(1);
}

.modal-header {
  display: flex;
  justify-content: space-between;
  align-items: center;
  padding: var(--spacing-lg);
  border-bottom: 1px solid rgba(0, 0, 0, 0.1);
}

.modal-close {
  background: none;
  border: none;
  color: var(--text-color);
  font-size: var(--font-size-lg);
  cursor: pointer;
  padding: var(--spacing-sm);
  border-radius: var(--border-radius-sm);
  transition: all var(--transition-fast);
}

.modal-close:hover {
  background-color: rgba(0, 0, 0, 0.1);
}

.modal-close:focus {
  outline: 2px solid var(--text-color);
  outline-offset: 2px;
}

.modal-body {
  padding: var(--spacing-lg);
}

/* Country Detail Content */
.country-detail-content {
  display: grid;
  gap: var(--spacing-xl);
}

@media (min-width: 768px) {
  .country-detail-content {
    grid-template-columns: 1fr 1fr;
    gap: var(--spacing-3xl);
  }
}

.country-detail-flag {
  width: 100%;
  height: auto;
  border-radius: var(--border-radius-md);
  box-shadow: var(--shadow);
}

.country-detail-info h2 {
  font-size: var(--font-size-xl);
  font-weight: var(--font-weight-extra-bold);
  margin-bottom: var(--spacing-lg);
  color: var(--text-color);
}

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

@media (min-width: 480px) {
  .country-detail-grid {
    grid-template-columns: 1fr 1fr;
  }
}

.country-detail-section {
  display: flex;
  flex-direction: column;
  gap: var(--spacing-sm);
}

.country-detail-item {
  font-size: var(--font-size-detail);
  color: var(--text-color);
}

.country-detail-item strong {
  font-weight: var(--font-weight-semibold);
}

.border-countries {
  margin-top: var(--spacing-xl);
}

.border-countries h3 {
  font-size: var(--font-size-lg);
  font-weight: var(--font-weight-semibold);
  margin-bottom: var(--spacing-md);
  color: var(--text-color);
}

.border-countries-list {
  display: flex;
  flex-wrap: wrap;
  gap: var(--spacing-sm);
}

.border-country {
  padding: var(--spacing-xs) var(--spacing-md);
  background-color: var(--elements-color);
  border: none;
  border-radius: var(--border-radius-sm);
  color: var(--text-color);
  font-family: inherit;
  font-size: var(--font-size-homepage);
  cursor: pointer;
  text-decoration: none;
  box-shadow: var(--shadow);
  transition: all var(--transition-fast);
}

.border-country:hover {
  box-shadow: var(--shadow-medium);
  transform: translateY(-1px);
}

.border-country:focus {
  outline: 2px solid var(--text-color);
  outline-offset: 2px;
}


.sr-only {
  position: absolute;
  width: 1px;
  height: 1px;
  padding: 0;
  margin: -1px;
  overflow: hidden;
  clip: rect(0, 0, 0, 0);
  white-space: nowrap;
  border: 0;
}


@media (max-width: 767px) {
  .modal-content {
    margin: var(--spacing-md);
    max-width: calc(100vw - 2rem);
  }
  
  .country-detail-content {
    gap: var(--spacing-lg);
  }
  
  .country-detail-grid {
    grid-template-columns: 1fr;
  }
}

.country-card {
  animation: fadeInUp 0.5s ease-out forwards;
  opacity: 0;
  transform: translateY(20px);
}

@keyframes fadeInUp {
  to {
    opacity: 1;
    transform: translateY(0);
  }
}

/* Stagger animation for multiple cards */
.country-card:nth-child(1) { animation-delay: 0.1s; }
.country-card:nth-child(2) { animation-delay: 0.2s; }
.country-card:nth-child(3) { animation-delay: 0.3s; }
.country-card:nth-child(4) { animation-delay: 0.4s; }
.country-card:nth-child(5) { animation-delay: 0.5s; }
.country-card:nth-child(6) { animation-delay: 0.6s; }
.country-card:nth-child(7) { animation-delay: 0.7s; }
.country-card:nth-child(8) { animation-delay: 0.8s; }
  }
}