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

:root {
  --bg-color: #0f0f1a;
  --card-bg: #1a1a2e;
  --card-bg-hover: #22223a;
  --text-primary: #ffffff;
  --text-secondary: #a0a0b0;
  --accent-blue: #4a90d9;
  --accent-green: #3cb371;
  --accent-orange: #ff8c42;
  --accent-purple: #9b59b6;
  --input-bg: #252540;
  --border-color: #2a2a45;
  --slider-track: #3a3a55;
  --eur-color: #4a90d9;
  --hnl-color: #3cb371;
  --cop-color: #ff8c42;
  --usd-color: #9b59b6;
}

html, body {
  height: 100%;
}

body {
  font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, Oxygen, Ubuntu, sans-serif;
  background-color: var(--bg-color);
  color: var(--text-primary);
  line-height: 1.5;
}

header {
  text-align: center;
  padding: 24px 16px 16px;
  position: sticky;
  top: 0;
  background: var(--bg-color);
  z-index: 100;
  border-bottom: 1px solid var(--border-color);
}

header h1 {
  font-size: 28px;
  font-weight: 700;
  margin-bottom: 4px;
  background: linear-gradient(135deg, var(--eur-color), var(--hnl-color));
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
}

header p {
  font-size: 12px;
  color: var(--text-secondary);
}

main {
  padding: 16px;
  display: flex;
  flex-direction: column;
  gap: 16px;
  max-width: 500px;
  margin: 0 auto;
}

.currency-card {
  background: var(--card-bg);
  border-radius: 16px;
  padding: 16px;
  border: 1px solid var(--border-color);
  transition: transform 0.2s ease, box-shadow 0.2s ease;
  position: relative;
}

.currency-card:active {
  transform: scale(0.98);
}

.currency-card[data-currency="EUR"] { --card-accent: var(--eur-color); }
.currency-card[data-currency="HNL"] { --card-accent: var(--hnl-color); }
.currency-card[data-currency="COP"] { --card-accent: var(--cop-color); }
.currency-card[data-currency="USD"] { --card-accent: var(--usd-color); }

.card-top-right {
  position: absolute;
  top: 12px;
  right: 12px;
}

.rate-comparison {
  font-size: 11px;
  font-weight: 600;
  color: var(--text-secondary);
  opacity: 0.7;
}

.currency-header {
  display: flex;
  align-items: center;
  gap: 8px;
  margin-bottom: 12px;
}

.currency-header .flag {
  font-size: 24px;
}

.currency-header .code {
  font-weight: 700;
  font-size: 18px;
  color: var(--card-accent);
}

.currency-header .name {
  color: var(--text-secondary);
  font-size: 14px;
}

.input-row {
  margin-bottom: 8px;
}

.amount-input {
  width: 100%;
  background: var(--input-bg);
  border: 2px solid var(--border-color);
  border-radius: 12px;
  padding: 12px 16px;
  font-size: 28px;
  font-weight: 600;
  color: var(--text-primary);
  outline: none;
  transition: border-color 0.2s ease;
  -moz-appearance: textfield;
}

.amount-input::-webkit-outer-spin-button,
.amount-input::-webkit-inner-spin-button {
  -webkit-appearance: none;
  margin: 0;
}

.amount-input:focus {
  border-color: var(--card-accent);
}

.slider-container {
  padding: 8px 4px;
}

.amount-slider {
  width: 100%;
  height: 8px;
  -webkit-appearance: none;
  appearance: none;
  background: var(--slider-track);
  border-radius: 4px;
  outline: none;
  cursor: pointer;
}

.amount-slider::-webkit-slider-thumb {
  -webkit-appearance: none;
  appearance: none;
  width: 24px;
  height: 24px;
  border-radius: 50%;
  background: var(--card-accent);
  cursor: pointer;
  box-shadow: 0 2px 8px rgba(0, 0, 0, 0.3);
  transition: transform 0.1s ease;
}

.amount-slider::-webkit-slider-thumb:active {
  transform: scale(1.15);
}

.amount-slider::-moz-range-thumb {
  width: 24px;
  height: 24px;
  border-radius: 50%;
  background: var(--card-accent);
  cursor: pointer;
  border: none;
  box-shadow: 0 2px 8px rgba(0, 0, 0, 0.3);
}

.quick-chips {
  display: flex;
  gap: 6px;
  margin-top: 8px;
  flex-wrap: wrap;
}

.chip {
  background: var(--input-bg);
  border: 1px solid var(--border-color);
  border-radius: 12px;
  padding: 4px 10px;
  font-size: 11px;
  font-weight: 500;
  color: var(--text-secondary);
  cursor: pointer;
  transition: all 0.15s ease;
}

.chip:hover {
  background: var(--card-bg-hover);
  color: var(--text-primary);
  border-color: var(--card-accent);
}

.chip:active {
  transform: scale(0.95);
}

footer {
  padding: 16px;
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 8px;
}

.footer-controls {
  display: flex;
  gap: 12px;
}

#compare-toggle-btn, #refresh-btn {
  background: linear-gradient(135deg, var(--eur-color), var(--hnl-color));
  color: white;
  border: none;
  padding: 8px 16px;
  border-radius: 16px;
  font-size: 14px;
  font-weight: 500;
  cursor: pointer;
  transition: transform 0.2s ease, opacity 0.2s ease;
}

#compare-toggle-btn:active:not(:disabled), #refresh-btn:active:not(:disabled) {
  transform: scale(0.95);
}

#compare-toggle-btn:disabled, #refresh-btn:disabled {
  opacity: 0.5;
  cursor: not-allowed;
  background: var(--text-secondary);
}

.offline-status {
  font-size: 12px;
  color: var(--text-secondary);
}

.offline-status.online {
  color: var(--accent-green);
}

.offline-status.offline {
  color: var(--accent-orange);
}

@media (min-width: 600px) {
  main {
    flex-direction: row;
    flex-wrap: wrap;
    max-width: 800px;
  }

  .currency-card {
    flex: 1 1 calc(50% - 8px);
    min-width: 280px;
  }

  footer {
    position: fixed;
    bottom: 0;
    left: 0;
    right: 0;
    background: linear-gradient(to top, var(--bg-color) 80%, transparent);
  }
}

@media (min-width: 900px) {
  main {
    max-width: 1000px;
  }

  .currency-card {
    flex: 1 1 calc(25% - 12px);
  }
}

.rates-table-section {
  max-width: 500px;
  margin: 24px auto 48px;
  padding: 0 16px;
  text-align: center;
}

.rates-table-section h2 {
  font-size: 16px;
  font-weight: 600;
  color: var(--text-secondary);
  margin-bottom: 12px;
}

.rates-table {
  width: 100%;
  border-collapse: collapse;
  font-size: 13px;
  background: var(--card-bg);
  border-radius: 12px;
  overflow: hidden;
}

.rates-table th,
.rates-table td {
  padding: 10px 12px;
  text-align: left;
  border-bottom: 1px solid var(--border-color);
}

.rates-table th {
  background: var(--input-bg);
  color: var(--text-secondary);
  font-weight: 600;
}

.rates-table td:last-child,
.rates-table th:last-child {
  text-align: right;
}

.rates-table tr:last-child td {
  border-bottom: none;
}

.rates-caption {
  margin-top: 12px;
  font-size: 11px;
  color: var(--text-secondary);
  opacity: 0.7;
  line-height: 1.5;
}