:root {
  --bg: #f4f4f9;
  --text: #333;
  --accent: #007bff;
  --card: #ffffff;
}
body.dark {
  --bg: #1a1a2e;
  --text: #f1f1f1;
  --accent: #00c3ff;
  --card: #252537;
}

body {
  font-family: 'Poppins', sans-serif;
  margin: 0;
  padding: 0;
  background: var(--bg);
  color: var(--text);
  transition: background 0.4s, color 0.4s;
  position: relative;
  overflow-x: hidden;
}

header {
  text-align: center;
  padding: 2rem;
  background: var(--card);
  box-shadow: 0 4px 8px rgba(0,0,0,0.1);
}

.profile-img {
  width: 160px;
  height: 160px;
  border-radius: 50%;
  object-fit: cover;
  border: 4px solid #4facfe;
  box-shadow: 0 8px 20px rgba(0,0,0,0.3);
}


h1 {
  margin: 0;
  font-size: 2rem;
}

.highlight {
  color: var(--accent);
}

button#toggleTheme {
  background: var(--accent);
  color: #fff;
  border: none;
  padding: 0.5rem 1rem;
  margin-top: 1rem;
  border-radius: 5px;
  cursor: pointer;
  font-weight: bold;
  transition: background 0.3s;
}

button#toggleTheme:hover {
  background: #005dc1;
}

main {
  max-width: 800px;
  margin: 2rem auto;
  padding: 1rem;
}

section {
  background: var(--card);
  border-radius: 1rem;
  padding: 1.5rem;
  margin-bottom: 2rem;
  box-shadow: 0 2px 10px rgba(0,0,0,0.05);
}

h2 {
  color: var(--accent);
  margin-bottom: 1rem;
}

ul.hobbies {
  list-style: none;
  padding: 0;
}

ul.hobbies li {
  background: var(--accent);
  color: white;
  margin: 0.5rem 0;
  padding: 0.5rem 1rem;
  border-radius: 5px;
  display: inline-block;
}

a {
  color: var(--accent);
  text-decoration: none;
}

a:hover {
  text-decoration: underline;
}

footer {
  text-align: center;
  padding: 1rem;
  background: var(--card);
  box-shadow: 0 -2px 10px rgba(0,0,0,0.05);
}

#scrollTopBtn {
  position: fixed;
  bottom: 20px;
  right: 20px;
  padding: 0.6rem;
  font-size: 1.2rem;
  border: none;
  border-radius: 50%;
  background: var(--accent);
  color: white;
  cursor: pointer;
  display: none;
  z-index: 999;
}

#bubbles {
  position: fixed;
  top: 0;
  left: 0;
  width: 100%;
  height: 100%;
  pointer-events: none;
  z-index: 0;
  overflow: hidden;
}

.bubble {
  position: absolute;
  width: 10px;
  height: 10px;
  background: var(--accent);
  border-radius: 50%;
  animation: floatUp linear infinite;
}

@keyframes floatUp {
  from {
    transform: translateY(100vh);
  }
  to {
    transform: translateY(-10vh);
  }
}