/* Reset and font */
* {
  margin: 0;
  padding: 0;
  box-sizing: border-box;
  font-family: "Segoe UI", Tahoma, Geneva, Verdana, sans-serif;
}

body {
  background: linear-gradient(to right, #4facfe, #00f2fe);
  min-height: 100vh;
  display: flex;
  justify-content: center;
  align-items: center;
  padding: 20px;
  background-image: url("https://images.unsplash.com/photo-1581090700227-1e8bfe7eb1b0?auto=format&fit=crop&w=1500&q=80");
  background-size: cover;
  background-blend-mode: overlay;
  transition: background 0.5s ease;
}

/* Container */
.container {
  background-color: rgba(255, 255, 255, 0.95);
  border-radius: 20px;
  padding: 30px 40px;
  max-width: 400px;
  width: 100%;
  box-shadow: 0 8px 30px rgba(0, 0, 0, 0.2);
  animation: slideUp 0.8s ease-out;
}

/* Heading */
.container h1 {
  text-align: center;
  margin-bottom: 20px;
  color: #333;
}

form {
  display: flex;
  flex-direction: column;
  gap: 15px;
  margin-bottom: 20px;
}

input {
  padding: 12px;
  border: 1px solid #ccc;
  border-radius: 10px;
  transition: all 0.3s ease;
}

input:focus {
  border-color: #4facfe;
  outline: none;
  transform: scale(1.02);
}

button {
  background-color: #4facfe;
  color: white;
  padding: 12px;
  border: none;
  border-radius: 10px;
  cursor: pointer;
  font-weight: bold;
  transition: all 0.3s ease;
}

button:hover {
  background-color: #00c6ff;
  transform: scale(1.05);
}

#expense-list {
  list-style: none;
  margin-top: 10px;
}

#expense-list li {
  background: #f5f5f5;
  margin-bottom: 10px;
  padding: 10px 15px;
  border-radius: 10px;
  display: flex;
  justify-content: space-between;
  align-items: center;
  animation: fadeIn 0.4s ease-in;
}

#expense-list li button {
  background-color: #ff6b6b;
  padding: 6px 10px;
  border-radius: 8px;
  font-size: 0.8em;
  transition: 0.2s;
  border: none;
  color: white;
}

#expense-list li button:hover {
  background-color: #ff4c4c;
}

#total {
  margin-top: 20px;
  text-align: center;
}

#total h3 {
  color: #333;
}

/* Toggle switch */
.switch {
  position: absolute;
  top: 20px;
  right: 20px;
  width: 50px;
  height: 28px;
}

.switch input {
  opacity: 0;
  width: 0;
  height: 0;
}

.slider {
  position: absolute;
  cursor: pointer;
  background-color: #ccc;
  border-radius: 34px;
  top: 0;
  left: 0;
  right: 0;
  bottom: 0;
  transition: 0.4s;
}

.slider:before {
  content: "";
  height: 20px;
  width: 20px;
  left: 4px;
  bottom: 4px;
  background-color: white;
  border-radius: 50%;
  position: absolute;
  transition: 0.4s;
}

input:checked + .slider {
  background-color: #4facfe;
}

input:checked + .slider:before {
  transform: translateX(22px);
}

/* Dark Mode */
body.dark {
  background: #121212;
  background-image: none;
  color: #f0f0f0;
}

body.dark .container {
  background-color: #1e1e1e;
  box-shadow: 0 0 20px rgba(255, 255, 255, 0.05);
}

body.dark input,
body.dark button,
body.dark #expense-list li {
  background-color: #2c2c2c;
  color: #fff;
}

body.dark button:hover {
  background-color: #00c6ff;
}