* {
  margin: 0;
  padding: 0;
  box-sizing: border-box;
}

body {
  font-family: 'Segoe UI', sans-serif;
  background: #0d1117;
  color: #c9d1d9;
  line-height: 1.6;
  transition: background 0.3s, color 0.3s;
}

body.light {
  background: #ffffff;
  color: #1f1f1f;
}

.container {
  max-width: 960px;
  margin: 0 auto;
  padding: 1rem;
}

header {
  position: fixed;
  top: 0;
  width: 100%;
  background: rgba(13, 17, 23, 0.9);
  padding: 1rem;
  z-index: 1000;
  transition: top 0.3s;
}

header.hidden {
  top: -80px;
}

header .container {
  display: flex;
  justify-content: space-between;
  align-items: center;
}

h1 {
  font-size: 1.5rem;
  color: #58a6ff;
}

#themeToggle {
  background: none;
  border: none;
  font-size: 1.5rem;
  cursor: pointer;
  color: inherit;
}

main {
  padding-top: 100px;
}

.intro {
  text-align: center;
  margin-bottom: 2rem;
}

.pillars {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(220px, 1fr));
  gap: 1.5rem;
  margin-bottom: 3rem;
}

.pillar {
  background: #161b22;
  padding: 1rem;
  border-radius: 10px;
  box-shadow: 0 0 15px #0d1117;
  transition: transform 0.3s, background 0.3s;
}

.pillar:hover {
  transform: translateY(-5px);
  background: #21262d;
}

.mantra {
  background: #21262d;
  padding: 1.5rem;
  border-radius: 10px;
}

.mantra h2 {
  margin-bottom: 1rem;
  text-align: center;
}

footer {
  text-align: center;
  padding: 1rem;
  background: #0d1117;
  font-size: 0.9rem;
}

/* Reveal animation */
.reveal {
  opacity: 0;
  transform: translateY(20px);
  transition: opacity 0.6s ease, transform 0.6s ease;
}

.reveal.active {
  opacity: 1;
  transform: translateY(0);
}