:root {
  --primary: #4361ee;
  --primary-hover: #3a56d4;
  --success: #4cc9f0;
  --success-hover: #2bb4e0;
  --text-light: #f8f9fa;
  --text-dark: #212529;
  --bg-light: #f8f9fa;
  --bg-dark: #121212;
  --card-light: #ffffff;
  --card-dark: #1e1e1e;
  --border-light: #e9ecef;
  --border-dark: #333333;
  --transition: all 0.3s cubic-bezier(0.25, 0.8, 0.25, 1);
}

body {
  font-family: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, Oxygen, Ubuntu, Cantarell, sans-serif;
  max-width: 600px;
  margin: 40px auto;
  padding: 30px;
  text-align: center;
  transition: var(--transition);
  box-sizing: border-box;
  background-color: var(--bg-light);
  color: var(--text-dark);
  border-radius: 16px;
  box-shadow: 0 4px 30px rgba(0, 0, 0, 0.05);
}

body.dark {
  background-color: var(--bg-dark);
  color: var(--text-light);
  box-shadow: 0 4px 30px rgba(0, 0, 0, 0.3);
}

#themeToggle {
  position: absolute;
  top: 20px;
  right: 20px;
  background: none;
  border: none;
  cursor: pointer;
  padding: 8px;
  border-radius: 50%;
  width: 40px;
  height: 40px;
  display: flex;
  align-items: center;
  justify-content: center;
  transition: all 0.3s ease;
}

#themeToggle svg {
  width: 24px;
  height: 24px;
  transition: all 0.3s ease;
}

/* Light theme icon colors */
body.light #themeToggle {
  background: rgba(0, 0, 0, 0.05);
}

body.light #themeToggle .moon-icon {
  display: block;
  fill: #333;
}

body.light #themeToggle .sun-icon {
  display: none;
}

/* Dark theme icon colors */
body.dark #themeToggle {
  background: rgba(255, 255, 255, 0.1);
}

body.dark #themeToggle .moon-icon {
  display: none;
}

body.dark #themeToggle .sun-icon {
  display: block;
  fill: #f1f1f1;
}

/* Hover effects */
#themeToggle:hover {
  transform: scale(1.1);
}

body.light #themeToggle:hover {
  background: rgba(0, 0, 0, 0.1);
}

body.dark #themeToggle:hover {
  background: rgba(255, 255, 255, 0.2);
}

h1 {
  font-size: 2.2em;
  margin-bottom: 25px;
  font-weight: 700;
  background: linear-gradient(90deg, #4361ee, #4cc9f0);
  -webkit-background-clip: text;
  background-clip: text;
  color: transparent;
  letter-spacing: -0.5px;
}

/* Modern file input */
.file-upload-container {
  position: relative;
  margin: 20px 0;
}

.file-upload-label {
  display: block;
  padding: 18px;
  border: 2px dashed #ccc;
  border-radius: 12px;
  cursor: pointer;
  transition: var(--transition);
  background-color: var(--card-light);
}

body.dark .file-upload-label {
  background-color: var(--card-dark);
  border-color: var(--border-dark);
}

.file-upload-label:hover {
  border-color: var(--primary);
  transform: translateY(-2px);
}

.file-upload-label span {
  display: block;
  margin-bottom: 8px;
  font-weight: 500;
  color: var(--primary);
}

.file-upload-label small {
  color: #6c757d;
  font-size: 0.9em;
}

body.dark .file-upload-label small {
  color: #aaa;
}

#audioUpload {
  position: absolute;
  width: 1px;
  height: 1px;
  padding: 0;
  margin: -1px;
  overflow: hidden;
  clip: rect(0, 0, 0, 0);
  border: 0;
}

/* Modern text input */
.input-group {
  margin: 20px 0;
  text-align: left;
}

.input-group label {
  display: block;
  margin-bottom: 8px;
  font-weight: 500;
  color: var(--text-dark);
}

body.dark .input-group label {
  color: var(--text-light);
}

input[type="text"],
input[type="file"],
select {
  width: 100%;
  padding: 15px;
  font-size: 1em;
  border: 2px solid var(--border-light);
  border-radius: 12px;
  transition: var(--transition);
  background-color: var(--card-light);
  color: var(--text-dark);
  box-sizing: border-box;
}

body.dark input[type="text"],
body.dark input[type="file"],
body.dark select {
  background-color: var(--card-dark);
  border-color: var(--border-dark);
  color: var(--text-light);
}

input[type="text"]:focus,
select:focus {
  outline: none;
  border-color: var(--primary);
  box-shadow: 0 0 0 3px rgba(67, 97, 238, 0.2);
}

/* Buttons */
.button-group {
  margin: 30px 0;
}

button {
  background-color: var(--primary);
  color: white;
  padding: 16px 32px;
  border: none;
  border-radius: 12px;
  font-size: 1em;
  font-weight: 600;
  cursor: pointer;
  transition: var(--transition);
  box-shadow: 0 4px 6px rgba(0, 0, 0, 0.1);
}

button:hover {
  background-color: var(--primary-hover);
  transform: translateY(-2px);
  box-shadow: 0 6px 12px rgba(0, 0, 0, 0.15);
}

button:active {
  transform: translateY(0);
}

#downloadBtn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 8px;
  margin-top: 25px;
  text-decoration: none;
  color: white;
  background-color: var(--primary);
  padding: 15px 30px;
  border-radius: 12px;
  font-weight: 600;
  transition: var(--transition);
  box-shadow: 0 4px 6px rgba(0, 0, 0, 0.1);
}

#downloadBtn:hover {
  background-color: var(--primary-hover);
  transform: translateY(-2px);
  box-shadow: 0 6px 12px rgba(0, 0, 0, 0.15);
}

#downloadBtn::before {
  content: "↓";
  font-size: 1.2em;
}

/* Canvas */
canvas {
  display: block;
  margin: 30px auto;
  max-width: 100%;
  border-radius: 16px;
  box-shadow: 0 8px 32px rgba(0, 0, 0, 0.1);
  transition: var(--transition);
}

body.dark canvas {
  box-shadow: 0 8px 32px rgba(0, 0, 0, 0.3);
}

#status {
  margin: 20px auto;
  width: 100%;
  height: 6px;
  background-color: rgba(67, 97, 238, 0.1);
  border-radius: 3px;
  overflow: hidden;
  display: none;
}

#status-progress {
  height: 100%;
  width: 0%;
  background: linear-gradient(90deg, #4361ee, #4cc9f0);
  border-radius: 3px;
  transition: width 0.3s ease;
}

body.dark #status {
  background-color: rgba(67, 97, 238, 0.2);
}

/* Responsive Design */
@media (max-width: 640px) {
  body {
    margin: 20px;
    padding: 20px;
  }

  h1 {
    font-size: 1.8em;
  }
}

@media (max-width: 480px) {
  body {
    margin: 15px;
    padding: 15px;
  }

  h1 {
    font-size: 1.6em;
  }

  button,
  #downloadBtn {
    padding: 14px 24px;
  }
}