/* Reset default margin and padding for all elements */
* {
  margin: 0;
  padding: 0;
  box-sizing: border-box;
}

/* Body styling: center content with gradient background */
body {
  display: flex;
  flex-direction: column;
  justify-content: center;
  align-items: center;
  gap: 50px;
  height: 100vh;
  background: linear-gradient(135deg, #1a1a2e, #16213e, #0f3460);
  font-family: 'Courier New', monospace;
  color: #fff;
  transition: background 0.5s ease, color 0.5s ease;
}

/* Timer display: glowing digital clock effect */
p {
  font-size: 90px;
  font-weight: bold;
  letter-spacing: 3px;
  color: #00ffcc;
  text-shadow: 0 0 10px #00ffcc, 0 0 20px #00ffcc, 0 0 30px #00bfae;
  transition: color 0.3s ease, text-shadow 0.3s ease;
}

/* Circle container for Start and Stop buttons (glassmorphism) */
.start-stop {
  width: 240px;
  height: 240px;
  border-radius: 50%;
  background: rgba(255, 255, 255, 0.1);
  backdrop-filter: blur(12px);
  border: 2px solid rgba(255, 255, 255, 0.2);
  display: flex;
  justify-content: center;
  align-items: center;
  gap: 20px;
  box-shadow: 0 8px 25px rgba(0, 0, 0, 0.4);
  transition: all 0.3s ease;
}

/* General button styling */
.start-stop button,
.resetBtn,
.themeToggleBtn {
  padding: 10px 20px;
  border: none;
  border-radius: 25px;
  cursor: pointer;
  font-size: 14px;
  font-weight: 600;
  color: #fff;
  transition: all 0.3s ease;
  box-shadow: 0 4px 15px rgba(0, 0, 0, 0.3);
}

/* Reset button styling */
.resetBtn {
  background: linear-gradient(135deg, #43e97b, #38f9d7);
}
.resetBtn:hover {
  transform: scale(1.05);
  box-shadow: 0 6px 20px rgba(56, 249, 215, 0.6);
}

/* Start button styling */
.startBtn {
  background: linear-gradient(135deg, #2196f3, #00c6ff);
}
.startBtn:hover {
  transform: scale(1.1);
  box-shadow: 0 6px 20px rgba(0, 198, 255, 0.6);
}

/* Stop button styling */
.stopBtn {
  background: linear-gradient(135deg, #f44336, #ff6b6b);
}
.stopBtn:hover {
  transform: scale(1.1);
  box-shadow: 0 6px 20px rgba(255, 107, 107, 0.6);
}

/* Theme toggle button */
.themeToggleBtn {
  background: linear-gradient(135deg, #ff9800, #ffb74d);
  font-size: 16px;
}
.themeToggleBtn:hover {
  transform: scale(1.05);
  box-shadow: 0 6px 20px rgba(255, 183, 77, 0.6);
}

/* Light theme */
body.light-theme {
  background: linear-gradient(135deg, #f0f0f0, #e0e0e0);
  color: #000;
}
body.light-theme p {
  color: #333;
  text-shadow: 0 0 5px #aaa;
}
body.light-theme .start-stop {
  background: rgba(0, 0, 0, 0.05);
  border: 2px solid rgba(0, 0, 0, 0.1);
}

/* Responsive adjustments */
@media (max-width: 600px) {
  p {
    font-size: 60px;
  }
  .start-stop {
    width: 200px;
    height: 200px;
    gap: 15px;
  }
}