:root {
  --primary-color: #5c62e2;
  --primary-dark: #4549b8;
  --secondary-color: #ff6b6b;
  --text-color: #333;
  --bg-color: #f8f9fa;
  --card-bg: #ffffff;
  --border-color: #e0e0e0;
  --shadow: 0 4px 10px rgba(0, 0, 0, 0.05);
  --success-color: #4CAF50;
  --font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
  --worm-color: #5c62e2;
  --worm-head: #ff6b6b;
}

.dark-theme {
  --primary-color: #7377ff;
  --primary-dark: #5c62e2;
  --secondary-color: #ff8585;
  --text-color: #e0e0e0;
  --bg-color: #121212;
  --card-bg: #1e1e1e;
  --border-color: #333;
  --shadow: 0 4px 10px rgba(0, 0, 0, 0.2);
  --success-color: #66bb6a;
  --worm-color: #7377ff;
  --worm-head: #ff8585;
}

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

body {
  font-family: var(--font-family);
  background-color: var(--bg-color);
  color: var(--text-color);
  line-height: 1.6;
  transition: background-color 0.3s, color 0.3s;
}

#app {
  display: flex;
  flex-direction: column;
  min-height: 100vh;
}

header {
  background-color: var(--card-bg);
  padding: 1rem 2rem;
  box-shadow: var(--shadow);
  display: flex;
  justify-content: space-between;
  align-items: center;
}

.logo {
  display: flex;
  align-items: center;
}

.logo h1 {
  margin-left: 1rem;
  font-size: 1.5rem;
  font-weight: 600;
}

.worm {
  stroke: var(--worm-color);
  stroke-linecap: round;
  animation: wormAnimation 3s infinite alternate;
}

.worm-head {
  fill: var(--worm-head);
  animation: wormHeadAnimation 3s infinite alternate;
}

@keyframes wormAnimation {
  0% {
    stroke-dasharray: 0 33;
    stroke-dashoffset: 0;
  }
  100% {
    stroke-dasharray: 33 33;
    stroke-dashoffset: -33;
  }
}

@keyframes wormHeadAnimation {
  0% { transform: translateX(0); }
  100% { transform: translateX(-3px); }
}

.theme-toggle button {
  background: none;
  border: none;
  color: var(--text-color);
  cursor: pointer;
  padding: 0.5rem;
  border-radius: 50%;
  display: flex;
  align-items: center;
  justify-content: center;
  transition: background-color 0.3s;
}

.theme-toggle button:hover {
  background-color: rgba(0, 0, 0, 0.1);
}

main {
  flex: 1;
  padding: 2rem;
  max-width: 1000px;
  margin: 0 auto;
  width: 100%;
}

.tabs {
  display: flex;
  border-bottom: 1px solid var(--border-color);
  margin-bottom: 2rem;
}

.tabs button {
  background: none;
  border: none;
  padding: 0.75rem 1.5rem;
  margin-right: 0.5rem;
  cursor: pointer;
  color: var(--text-color);
  font-weight: 500;
  border-bottom: 3px solid transparent;
  transition: all 0.3s;
}

.tabs button.active {
  border-bottom: 3px solid var(--primary-color);
  color: var(--primary-color);
}

.tab-panel {
  animation: fadeIn 0.3s ease-in-out;
}

@keyframes fadeIn {
  from { opacity: 0; }
  to { opacity: 1; }
}

.input-group, .output-group {
  margin-bottom: 1.5rem;
}

label {
  display: block;
  margin-bottom: 0.5rem;
  font-weight: 500;
}

textarea {
  width: 100%;
  height: 150px;
  padding: 0.75rem;
  border-radius: 6px;
  border: 1px solid var(--border-color);
  background-color: var(--card-bg);
  color: var(--text-color);
  font-family: var(--font-family);
  resize: vertical;
  transition: border-color 0.3s;
}

textarea:focus {
  border-color: var(--primary-color);
  outline: none;
}

.controls {
  display: flex;
  gap: 1rem;
  margin-bottom: 1.5rem;
}

button {
  padding: 0.6rem 1.2rem;
  border-radius: 6px;
  border: 1px solid var(--border-color);
  background-color: var(--card-bg);
  color: var(--text-color);
  cursor: pointer;
  font-family: var(--font-family);
  font-weight: 500;
  transition: all 0.3s;
}

button:hover {
  background-color: rgba(0, 0, 0, 0.05);
}

.primary-btn {
  background-color: var(--primary-color);
  color: white;
  border: none;
}

.primary-btn:hover {
  background-color: var(--primary-dark);
}

button:disabled {
  opacity: 0.6;
  cursor: not-allowed;
}

.encrypted-output, .decrypted-output {
  background-color: var(--card-bg);
  padding: 1rem;
  border-radius: 6px;
  border: 1px solid var(--border-color);
  overflow-x: auto;
}

.encrypted-output pre {
  font-family: monospace;
  white-space: pre-wrap;
  word-break: break-all;
  color: var(--worm-color);
}

.action-buttons {
  display: flex;
  gap: 0.5rem;
  margin-top: 0.5rem;
  justify-content: flex-end;
}

.action-buttons button {
  padding: 0.4rem;
  display: flex;
  align-items: center;
  justify-content: center;
}

.settings-group {
  background-color: var(--card-bg);
  padding: 1.5rem;
  border-radius: 6px;
  margin-bottom: 1.5rem;
  box-shadow: var(--shadow);
}

.settings-group h3 {
  margin-bottom: 1rem;
  padding-bottom: 0.5rem;
  border-bottom: 1px solid var(--border-color);
}

.setting-item {
  margin-bottom: 1rem;
}

.setting-item input[type="text"],
.setting-item input[type="password"],
.setting-item select {
  width: 100%;
  padding: 0.6rem;
  border-radius: 6px;
  border: 1px solid var(--border-color);
  background-color: var(--card-bg);
  color: var(--text-color);
}

.setting-item small {
  display: block;
  margin-top: 0.25rem;
  color: #666;
}

.setting-item.checkbox {
  display: flex;
  align-items: center;
}

.setting-item.checkbox input {
  margin-right: 0.5rem;
}

.settings-actions {
  display: flex;
  gap: 1rem;
  margin-top: 1rem;
}

.qr-modal {
  position: fixed;
  top: 0;
  left: 0;
  width: 100%;
  height: 100%;
  background-color: rgba(0, 0, 0, 0.5);
  display: flex;
  align-items: center;
  justify-content: center;
  z-index: 1000;
}

.qr-container {
  background-color: var(--card-bg);
  padding: 2rem;
  border-radius: 6px;
  box-shadow: var(--shadow);
  position: relative;
  text-align: center;
  max-width: 90%;
}

.close-btn {
  position: absolute;
  top: 0.5rem;
  right: 0.5rem;
  background: none;
  border: none;
  font-size: 1.5rem;
  cursor: pointer;
  color: var(--text-color);
}

.qr-code {
  margin: 1.5rem 0;
  display: flex;
  justify-content: center;
}

.download-btn {
  margin-top: 1rem;
  background-color: var(--primary-color);
  color: white;
  border: none;
}

.notification {
  position: fixed;
  bottom: -100px;
  left: 50%;
  transform: translateX(-50%);
  background-color: var(--success-color);
  color: white;
  padding: 0.75rem 1.5rem;
  border-radius: 6px;
  box-shadow: var(--shadow);
  transition: bottom 0.3s;
  z-index: 1000;
}

.notification.show {
  bottom: 20px;
}

.paypal-btn {
  background-color: #000000;
  color: #ffffff;
  border: none;
  display: flex;
  align-items: center;
  gap: 8px;
  font-weight: 600;
  transition: background-color 0.3s;
  margin: 0.5rem auto;
}

.paypal-btn:hover {
  background-color: #333333;
}

.donate-button {
  margin-top: 0.75rem;
  text-align: center;
}

.offline-notice {
  background-color: var(--card-bg);
  color: var(--secondary-color);
  padding: 0.5rem;
  text-align: center;
  font-size: 0.875rem;
  display: none;
}

.offline-notice.visible {
  display: block;
}

footer {
  text-align: center;
  padding: 1.5rem;
  color: #666;
  font-size: 0.875rem;
}

@media (max-width: 768px) {
  header {
    padding: 1rem;
  }
  
  main {
    padding: 1rem;
  }
  
  .tabs {
    overflow-x: auto;
    white-space: nowrap;
  }
  
  .tabs button {
    padding: 0.5rem 1rem;
  }
  
  .controls {
    flex-wrap: wrap;
  }
  
  .settings-actions {
    flex-direction: column;
  }
}