:root {
  --base-color: #ffffff;
  --text-color: #333333;
  --accent-color: #0071ff;
  --button-hover: #005bb5;
  --base-variant: #f0f0f0;
}

[data-theme="dark"] {
  --base-color: #2c2c2c;
  --text-color: #e0e0e0;
  --accent-color: #4dabff;
  --button-hover: #337ab7;
  --base-variant: #444444;
}

body {
  margin: 0;
  font-family: "Poppins", sans-serif;
  background-color: var(--base-color);
  color: var(--text-color);
  transition: background-color 0.4s, color 0.4s;
}

header {
  text-align: center;
  padding: 50px 20px;
}

h1 {
  font-weight: 600;
  margin-bottom: 20px;
}

.btn {
  padding: 10px 20px;
  font-size: 16px;
  font-weight: 500;
  color: #fff;
  background-color: var(--accent-color);
  border: none;
  border-radius: 5px;
  cursor: pointer;
  transition: background-color 0.3s;
}

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

#theme-switch {
  height: 50px;
  width: 50px;
  padding: 0;
  border-radius: 50%;
  background-color: var(--base-variant);
  display: flex;
  justify-content: center;
  align-items: center;
  position: fixed;
  top: 20px;
  right: 20px;
  cursor: pointer;
  box-shadow: 0 4px 6px rgba(0, 0, 0, 0.1);
  transition: background-color 0.3s;
}

#theme-switch svg {
  fill: var(--accent-color);
  transition: fill 0.3s;
}

#theme-switch svg:last-child {
  display: none;
}

[data-theme="dark"] #theme-switch svg:first-child {
  display: none;
}

[data-theme="dark"] #theme-switch svg:last-child {
  display: block;
}