:root {
  --bg-color: rgba(0,0,0,0.75);
  --text-color: white;
  --subtitle-color: #ccc;
  --primary-gradient: linear-gradient(135deg, #ff416c, #ff4b2b);
  --back-gradient: linear-gradient(135deg, #3a7bd5, #00d2ff);
}

body {
  min-height: 100vh;
  background: url("https://img.freepik.com/premium-vector/stunning-twilight-scene-digital-artwork-with-colorful-horizon_1292249-7953.jpg") no-repeat center center / cover;
  display: flex;
  justify-content: center;
  align-items: center;
  color: var(--text-color);
  transition: background 0.3s, color 0.3s;
  position: relative;
  margin: 0;
  padding: 0;
}

.container {
  background: var(--bg-color);
  padding: 30px;
  border-radius: 20px;
  text-align: center;
  width: 90%;
  max-width: 420px;
  transition: background 0.3s;
}

h1 {
  margin-bottom: 15px;
}

p {
  color: var(--subtitle-color);
  margin-bottom: 25px;
}

.app-list {
  display: flex;
  flex-direction: column;
  gap: 15px;
}

.app-button {
  text-decoration: none;
  padding: 14px;
  border-radius: 14px;
  color: white;
  font-size: 18px;
  font-weight: bold;
  background: var(--primary-gradient);
  transition: transform 0.2s, opacity 0.2s;
}

.app-button:hover {
  transform: scale(1.05);
  opacity: 0.9;
}

.back-button {
  background: var(--back-gradient);
}

.disabled {
  background: #555;
  opacity: 0.6;
  pointer-events: none;
}

/* DARK / LIGHT CLASS */
.light-mode {
  --bg-color: rgba(255,255,255,0.9);
  --text-color: black;
  --subtitle-color: #333;
  --primary-gradient: linear-gradient(135deg, #ff416c, #ff4b2b);
  --back-gradient: linear-gradient(135deg, #3a7bd5, #00d2ff);
}

.dark-mode {
  --bg-color: rgba(0,0,0,0.75);
  --text-color: white;
  --subtitle-color: #ccc;
  --primary-gradient: linear-gradient(135deg, #ff416c, #ff4b2b);
  --back-gradient: linear-gradient(135deg, #3a7bd5, #00d2ff);
}

/* Mode Switch Button */
#mode-switch {
  position: fixed;
  top: 15px;
  right: 15px;
  background: var(--primary-gradient);
  border: none;
  padding: 10px 15px;
  border-radius: 50%;
  font-size: 20px;
  cursor: pointer;
  transition: transform 0.2s;
  z-index: 100;
}

#mode-switch:hover {
  transform: scale(1.1);
}