:root {
  --background-color-light: #f0f0f0;
  --text-color-light: #333;
  --container-bg-light: #fff;
  --button-bg-light: #4CAF50;
  --button-text-light: white;
  --input-border-light: #ccc;

  --background-color-dark: #121212;
  --text-color-dark: #e0e0e0;
  --container-bg-dark: #1e1e1e;
  --button-bg-dark: #66bb6a;
  --button-text-dark: #121212;
  --input-border-dark: #555;
}

body {
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, Helvetica, Arial, sans-serif;
  display: flex;
  flex-direction: column;
  align-items: center;
  margin: 0;
  background-color: var(--background-color-light);
  color: var(--text-color-light);
  transition: background-color 0.3s, color 0.3s;
}

body.dark-mode {
  background-color: var(--background-color-dark);
  color: var(--text-color-dark);
}

.header {
  width: 100%;
  display: flex;
  justify-content: space-between;
  align-items: center;
  padding: 20px;
  box-sizing: border-box;
}

h1 {
  margin: 0;
}

.container {
  display: flex;
  gap: 10px;
  margin-bottom: 20px;
}

#youtube-url {
  width: 400px;
  padding: 12px;
  border: 1px solid var(--input-border-light);
  border-radius: 8px;
  font-size: 16px;
}

body.dark-mode #youtube-url {
  border-color: var(--input-border-dark);
  background-color: #333;
  color: var(--text-color-dark);
}

button {
  padding: 12px 20px;
  border: none;
  background-color: var(--button-bg-light);
  color: var(--button-text-light);
  border-radius: 8px;
  cursor: pointer;
  font-size: 16px;
  transition: background-color 0.2s;
}

body.dark-mode button {
  background-color: var(--button-bg-dark);
  color: var(--button-text-dark);
}

button:hover {
  opacity: 0.9;
}

#video-player-container {
  width: 80%;
  max-width: 640px;
  margin-bottom: 20px;
}

#video-player {
  border-radius: 8px;
}

#video-info {
  padding: 20px;
  border: 1px solid var(--input-border-light);
  border-radius: 8px;
  background-color: var(--container-bg-light);
  width: 80%;
  max-width: 600px;
  box-shadow: 0 2px 4px rgba(0,0,0,0.1);
}

body.dark-mode #video-info {
  border-color: var(--input-border-dark);
  background-color: var(--container-bg-dark);
  box-shadow: 0 2px 4px rgba(0,0,0,0.3);
}

.format-selection {
  display: flex;
  gap: 10px;
  margin-top: 15px;
}

#format-select {
  flex-grow: 1;
  padding: 10px;
  border-radius: 5px;
  border: 1px solid var(--input-border-light);
}

body.dark-mode #format-select {
  border-color: var(--input-border-dark);
  background-color: #333;
  color: var(--text-color-dark);
}

/* The switch - the box around the slider */
.theme-switch-wrapper {
  display: flex;
  align-items: center;
}
.theme-switch {
  position: relative;
  display: inline-block;
  width: 60px;
  height: 34px;
}
.theme-switch input {
  opacity: 0;
  width: 0;
  height: 0;
}
.slider {
  position: absolute;
  cursor: pointer;
  top: 0;
  left: 0;
  right: 0;
  bottom: 0;
  background-color: #ccc;
  -webkit-transition: .4s;
  transition: .4s;
}
.slider:before {
  position: absolute;
  content: "";
  height: 26px;
  width: 26px;
  left: 4px;
  bottom: 4px;
  background-color: white;
  -webkit-transition: .4s;
  transition: .4s;
}
input:checked + .slider {
  background-color: #2196F3;
}
input:focus + .slider {
  box-shadow: 0 0 1px #2196F3;
}
input:checked + .slider:before {
  -webkit-transform: translateX(26px);
  -ms-transform: translateX(26px);
  transform: translateX(26px);
}
.slider.round {
  border-radius: 34px;
}
.slider.round:before {
  border-radius: 50%;
}