:root {
  --bg-color: #0d0d0d;
  --bg-gradient: radial-gradient(circle at right bottom, #1f1f1f, #0d0d0d);
  --panel-bg: rgba(30, 30, 30, 0.4);
  --glass-border: rgba(255, 255, 255, 0.08);
  --text-main: #ffffff;
  --text-muted: #9ca3af;
  --accent-color: #00ff8cf5;
  --accent-hover: #00ff8cf5;
  --input-bg: rgba(0, 0, 0, 0.3);
  --shadow-color: rgba(0, 0, 0, 0.6);
}

[data-theme="light"] {
  --bg-color: #f3f4f6;
  --bg-gradient: radial-gradient(circle at right bottom, #ffffff, #e5e7eb);
  --panel-bg: rgba(255, 255, 255, 0.6);
  --glass-border: rgba(255, 255, 255, 0.6);
  --text-main: #1f2937;
  --text-muted: #6b7280;
  --accent-color: #00e07b;
  --accent-hover: #00c06a;
  --input-bg: rgba(255, 255, 255, 0.8);
  --shadow-color: rgba(0, 0, 0, 0.1);
}

* {
  margin: 0;
  padding: 0;
  box-sizing: border-box;
  font-family: 'Inter', sans-serif;
  transition: background-color 0.4s ease, color 0.4s ease, border-color 0.4s ease, box-shadow 0.4s ease;
}

body {
  display: flex;
  justify-content: center;
  align-items: center;
  min-height: 100vh;
  background: var(--bg-gradient);
  background-color: var(--bg-color);
  color: var(--text-main);
  position: relative;
}

/* Theme Toggle Button */
.theme-toggle {
  position: absolute;
  top: 2rem;
  right: 2rem;
  background: var(--panel-bg);
  border: 1px solid var(--glass-border);
  color: var(--text-main);
  width: 50px;
  height: 50px;
  border-radius: 50%;
  backdrop-filter: blur(12px);
  -webkit-backdrop-filter: blur(12px);
  cursor: pointer;
  display: flex;
  justify-content: center;
  align-items: center;
  font-size: 1.3rem;
  z-index: 10;
  box-shadow: 0 4px 15px var(--shadow-color);
}

.theme-toggle:hover {
  background: var(--accent-color);
  color: #fff;
  border-color: var(--accent-color);
  transform: scale(1.05) rotate(10deg);
}

/* Glassmorphism Container */
.container {
  background: var(--panel-bg);
  backdrop-filter: blur(24px);
  -webkit-backdrop-filter: blur(24px);
  border: 1px solid var(--glass-border);
  padding: 2.5rem;
  border-radius: 1.5rem;
  width: 90%;
  max-width: 420px;
  box-shadow: 0 25px 50px -12px var(--shadow-color);
}

h2 {
  font-size: 1.5rem;
  font-weight: 600;
  text-align: center;
  margin-bottom: 2rem;
  color: var(--text-main);
}

form {
  display: flex;
  flex-direction: column;
  gap: 1.5rem;
}

p {
  font-size: 0.85rem;
  color: var(--text-muted);
  margin-bottom: 0.5rem;
  font-weight: 500;
  text-transform: uppercase;
  letter-spacing: 0.05em;
}

form select,
button,
input {
  width: 100%;
  border: none;
  outline: none;
  border-radius: 0.75rem;
}

.input-wrapper {
  position: relative;
}

form input {
  background: var(--input-bg);
  border: 1px solid var(--glass-border);
  color: var(--text-main);
  font-size: 1.25rem;
  height: 3.5rem;
  padding: 0 1rem;
  font-weight: 600;
}

form input:focus {
  border-color: var(--accent-color);
  box-shadow: 0 0 0 2px rgba(255, 179, 71, 0.2);
}

.dropdown {
  display: flex;
  justify-content: space-between;
  align-items: center;
  margin-top: 0.5rem;
  position: relative;
}

.from, .to {
  width: 42%;
}

.select-container {
  display: flex;
  justify-content: space-between;
  align-items: center;
  background: var(--input-bg);
  border: 1px solid var(--glass-border);
  border-radius: 0.75rem;
  padding: 0.5rem;
  height: 3.5rem;
}

.select-container:hover {
  border-color: var(--accent-color);
}

.select-container img {
  width: 28px;
  height: 28px;
  border-radius: 50%;
  object-fit: cover;
}

.select-container select {
  font-size: 1rem;
  font-weight: 500;
  width: 100%;
  background: transparent;
  color: var(--text-main);
  padding-left: 0.5rem;
  cursor: pointer;
  appearance: none;
}

.select-container select option {
  background-color: var(--bg-color);
  color: var(--text-main);
}

.swap-icon {
  width: 40px;
  height: 40px;
  border-radius: 50%;
  background: var(--panel-bg);
  border: 1px solid var(--glass-border);
  color: var(--text-main);
  display: flex;
  justify-content: center;
  align-items: center;
  cursor: pointer;
  z-index: 2;
  margin-top: 1.25rem;
}

.swap-icon i {
  font-size: 1.1rem;
}

.swap-icon:hover {
  background: var(--accent-color);
  color: #000;
  border-color: var(--accent-color);
  transform: rotate(180deg);
  box-shadow: 0 0 15px var(--accent-color);
}

.msg-container {
  display: flex;
  flex-direction: column;
  gap: 0.5rem;
  margin: 1.5rem 0;
  text-align: center;
}

.result-box {
  display: flex;
  justify-content: center;
  align-items: center;
  gap: 0.75rem;
  min-height: 2.5rem;
}

.msg {
  font-size: 1.5rem;
  font-weight: 700;
  color: var(--accent-color);
  position: relative;
  overflow: hidden;
  border-radius: 0.25rem;
  padding: 0 0.5rem;
}

.copy-btn {
  background: transparent;
  color: var(--text-muted);
  width: auto;
  border: none;
  cursor: pointer;
  font-size: 1.25rem;
  transition: all 0.2s ease;
}

.copy-btn:hover {
  color: var(--accent-color);
  transform: scale(1.1);
}

.copy-btn:active {
  transform: scale(0.9);
}

/* Skeleton Loading Animation */
.skeleton {
  color: transparent !important;
  user-select: none;
}

.skeleton::before {
  content: "";
  position: absolute;
  top: 0;
  left: -100%;
  width: 200%;
  height: 100%;
  background: linear-gradient(
    90deg,
    transparent 0%,
    rgba(255, 255, 255, 0.1) 50%,
    transparent 100%
  );
  animation: shimmer 1.5s infinite linear;
}

[data-theme="light"] .skeleton::before {
  background: linear-gradient(
    90deg,
    transparent 0%,
    rgba(0, 0, 0, 0.1) 50%,
    transparent 100%
  );
}

@keyframes shimmer {
  0% { transform: translateX(0); }
  100% { transform: translateX(50%); }
}

.last-updated {
  font-size: 0.75rem;
  color: var(--text-muted);
}

.convert-btn {
  height: 3.5rem;
  background: var(--accent-color);
  color: #000;
  font-size: 1.15rem;
  font-weight: 700;
  cursor: pointer;
  box-shadow: 0 4px 15px var(--shadow-color);
}

.convert-btn:hover {
  background: var(--accent-hover);
  transform: translateY(-2px);
  box-shadow: 0 0 20px rgba(0, 255, 140, 0.4);
}

.convert-btn:active {
  transform: translateY(0);
}