body {
  font-family: Arial, sans-serif;
  background: #f5f5f5;
  display: flex;
  justify-content: center;
  align-items: center;
  min-height: 100vh;
  margin: 0;
}

.container {
  background: white;
  padding: 30px;
  border-radius: 12px;
  box-shadow: 0 0 15px rgba(0, 0, 0, 0.1);
  text-align: center;
  max-width: 600px;
  width: 90%;
}

h2 {
  margin-top: 0;
}

label {
  display: block;
  margin: 10px 0;
}

input[type="range"] {
  width: 100%;
  max-width: 440px;
}

.slider-label {
  display: inline-block;
  width: 80px;
  text-align: left;
  margin-right: 20px;
}

select, input[type="file"], button {
  margin-top: 8px;
}

.buttons {
  margin: 15px 0;
}

#seekBar {
  width: 100%;
  max-width: 400px;
  margin-top: 10px;
}

#timeDisplay {
  margin-top: 5px;
  margin-bottom: 15px;
}

#speedDisplay {
  margin-left: 10px;
}

body.dark-mode {
  background-color: #121212;
  color: #f1f1f1;
}

body.dark-mode .container {
  background-color: #1e1e1e;
  border: 1px solid #333;
  color: #f1f1f1;
}

body.dark-mode select,
body.dark-mode input[type="file"],
body.dark-mode input[type="range"],
body.dark-mode button {
  background-color: #333;
  color: #fff;
  border: 1px solid #444;
}

body.dark-mode .slider-label {
  color: #ddd;
}