:root {
  --primary: #000000;
  --primary-foreground: #ffffff;
  --accent: #3b82f6;
  --bg-app: #f4f4f4;
  --bg-card: #ffffff;
  --text-main: #09090b;
  --text-muted: #71717a;
  --border: #e4e4e7;
  --input-bg: #ffffff;
  --shadow: 0 1px 3px 0 rgb(0 0 0 / 0.1), 0 1px 2px -1px rgb(0 0 0 / 0.1);
  --radius: 12px;
  --transition: 0.2s cubic-bezier(0.4, 0, 0.2, 1);
}

.dark-theme {
  --primary: #ffffff;
  --primary-foreground: #000000;
  --bg-app: #09090b;
  --bg-card: #18181b;
  --text-main: #fafafa;
  --text-muted: #a1a1aa;
  --border: #27272a;
  --input-bg: #09090b;
  --shadow: 0 10px 15px -3px rgb(0 0 0 / 0.5);
}

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

body {
  font-family: "Plus Jakarta Sans", sans-serif;
  background-color: var(--bg-app);
  color: var(--text-main);
  transition: background-color var(--transition), color var(--transition);
  min-height: 100vh;
  display: flex;
  align-items: center;
  justify-content: center;
  padding: 20px;
}

.app-container {
  width: 100%;
  max-width: 480px;
  display: flex;
  flex-direction: column;
  gap: 24px;
}

header {
  display: flex;
  justify-content: space-between;
  align-items: center;
}

.logo {
  display: flex;
  align-items: center;
  gap: 10px;
  font-weight: 700;
  font-size: 1.25rem;
  color: var(--primary);
}

#theme-toggle {
  background: var(--bg-card);
  border: 1px solid var(--border);
  padding: 10px;
  border-radius: 12px;
  cursor: pointer;
  color: var(--text-main);
  transition: var(--transition);
  box-shadow: var(--shadow);
}

#theme-toggle:hover {
  transform: translateY(-2px);
}

.moon {
  display: none;
}
.dark-theme .moon {
  display: block;
}
.dark-theme .sun {
  display: none;
}

.converter-card {
  background: var(--bg-card);
  border-radius: var(--radius);
  padding: 40px;
  box-shadow: var(--shadow);
  border: 1px solid var(--border);
  display: flex;
  flex-direction: column;
  gap: 32px;
}

.input-group label,
.select-box label {
  display: block;
  font-size: 0.875rem;
  font-weight: 600;
  color: var(--text-muted);
  margin-bottom: 8px;
}

.amount-wrapper {
  position: relative;
  display: flex;
  align-items: center;
}

.currency-symbol {
  position: absolute;
  left: 16px;
  font-weight: 600;
  color: var(--text-muted);
}

#amount {
  width: 100%;
  padding: 16px 20px;
  border-radius: 8px;
  border: 1px solid var(--border);
  background: var(--input-bg);
  color: var(--text-main);
  font-size: 1.5rem;
  font-weight: 700;
  outline: none;
  transition: var(--transition);
}

#amount:focus {
  border-color: var(--accent);
  box-shadow: 0 0 0 4px rgba(59, 130, 246, 0.15);
}

.selectors-container {
  display: flex;
  flex-direction: column;
  gap: 16px;
  position: relative;
}

@media (min-width: 640px) {
  .selectors-container {
    flex-direction: row;
    align-items: flex-end;
  }
  .select-box {
    flex: 1;
  }
}

.swap-wrapper {
  display: flex;
  align-items: center;
  justify-content: center;
  padding: 0 8px;
}

#swap-btn {
  background: var(--bg-app);
  color: var(--text-main);
  border: 1px solid var(--border);
  width: 48px;
  height: 48px;
  border-radius: 8px;
  cursor: pointer;
  display: flex;
  align-items: center;
  justify-content: center;
  transition: all 0.4s cubic-bezier(0.34, 1.56, 0.64, 1);
}

#swap-btn:hover {
  transform: rotate(180deg);
  background: var(--primary);
  color: var(--primary-foreground);
  border-color: var(--primary);
}

#swap-btn:active {
  transform: rotate(180deg) scale(0.95);
}

.custom-select {
  position: relative;
  cursor: pointer;
}

.select-trigger {
  display: flex;
  align-items: center;
  gap: 12px;
  padding: 12px 16px;
  background: var(--input-bg);
  border: 2px solid var(--border);
  border-radius: 12px;
  transition: var(--transition);
}

.custom-select.active .select-trigger {
  border-color: var(--primary);
}

.flag-icon {
  width: 24px;
  height: 18px;
  border-radius: 2px;
  object-fit: cover;
  box-shadow: 0 2px 4px rgba(0, 0, 0, 0.1);
}

.options-list {
  position: absolute;
  top: calc(100% + 8px);
  left: 0;
  right: 0;
  background: var(--bg-card);
  border: 1px solid var(--border);
  border-radius: 12px;
  max-height: 250px;
  overflow-y: auto;
  z-index: 100;
  display: none;
  box-shadow: var(--shadow);
}

.custom-select.active .options-list {
  display: block;
  animation: fadeIn 0.2s ease-out;
}

.option-item {
  display: flex;
  align-items: center;
  gap: 12px;
  padding: 10px 16px;
  transition: background 0.2s;
}

.option-item:hover {
  background: var(--bg-app);
}

.result-container {
  margin-top: 12px;
  min-height: 140px;
  background: var(--bg-app);
  border-radius: 8px;
  padding: 24px;
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  position: relative;
}

.result-content {
  display: block;
  opacity: 1;
  transform: none;
  text-align: center;
  transition: opacity 0.3s ease;
}

.result-content.updating {
  opacity: 0.5;
}

.result-content.show {
  animation: slideUp 0.5s forwards cubic-bezier(0.175, 0.885, 0.32, 1.275);
}

.base-text {
  font-size: 0.875rem;
  color: var(--text-muted);
  margin-bottom: 4px;
}

.base-amount {
  font-size: 1rem;
  color: var(--text-muted);
  font-weight: 500;
}

.converted-amount {
  font-size: 2.25rem;
  font-weight: 800;
  color: var(--text-main);
  margin: 4px 0;
  letter-spacing: -0.025em;
}

.update-time {
  font-size: 0.75rem;
  color: var(--text-muted);
  margin-top: 8px;
}

/* Animations */
@keyframes fadeIn {
  from {
    opacity: 0;
    transform: translateY(-10px);
  }
  to {
    opacity: 1;
    transform: translateY(0);
  }
}

@keyframes slideUp {
  to {
    opacity: 1;
    transform: translateY(0) scale(1.05);
  }
}

footer {
  text-align: center;
  font-size: 0.8125rem;
  color: var(--text-muted);
}

footer a {
  color: var(--primary);
  text-decoration: none;
  font-weight: 600;
}

/* Scrollbar */
.options-list::-webkit-scrollbar {
  width: 6px;
}
.options-list::-webkit-scrollbar-track {
  background: transparent;
}
.options-list::-webkit-scrollbar-thumb {
  background: var(--border);
  border-radius: 10px;
}