:root {
  --purple: #6A0DAD;
  --green: #00C853;
  --light-green: #00FF99;
  --dark-bg: #0b0b0b;
  --light-bg: #f6f6f9;
  --light-text: #f0f0f0;
  --dark-text: #111;
}

body {
  background-color: var(--dark-bg);
  color: var(--light-text);
  line-height: 1.7;
  transition: background 0.5s, color 0.5s;
}
body.light {
  background-color: var(--light-bg);
  color: var(--dark-text);
}

* {
  margin: 0;
  padding: 0;
  box-sizing: border-box;
  font-family: 'Open Sans', sans-serif;
}

/* HEADER */
header {
  display: flex;
  justify-content: space-between;
  align-items: center;
  padding: 20px 60px;
  background: rgba(0,0,0,0.6);
  backdrop-filter: blur(6px);
  position: sticky;
  top: 0;
  z-index: 1000;
  transition: background 0.5s;
}
body.light header {
  background: rgba(255,255,255,0.8);
}

.logo {
  font-family: 'Poppins', sans-serif;
  font-size: 1.7rem;
  font-weight: 700;
  color: white;
  transition: color 0.5s;
}
body.light .logo {
  color: var(--purple);
}

nav {
  display: flex;
  align-items: center;
}
nav a {
  margin-left: 25px;
  color: var(--light-green);
  text-decoration: none;
  font-weight: 600;
  transition: 0.3s;
}
nav a:hover { color: white; }
body.light nav a:hover { color: var(--purple); }

.switches {
  display: flex;
  align-items: center;
  gap: 10px;
  margin-left: 25px;
}

.switch-btn {
  cursor: pointer;
  background: var(--light-green);
  border: none;
  padding: 6px 12px;
  border-radius: 20px;
  font-weight: 600;
  color: #000;
  transition: 0.3s;
}
.switch-btn:hover { background: white; color: var(--purple); }

/* HERO */
.hero {
  text-align: center;
  padding: 120px 40px;
  background: linear-gradient(135deg, var(--purple), var(--green));
  color: white;
}

.hero h1 {
  font-family: 'Poppins', sans-serif;
  font-size: 2.8rem;
  font-weight: 700;
  margin-bottom: 15px;
}

.hero p {
  font-size: 1.1rem;
  max-width: 800px;
  margin: 0 auto 30px;
}

.btn {
  background: var(--light-green);
  color: #000;
  padding: 12px 28px;
  border-radius: 25px;
  font-weight: 600;
  text-decoration: none;
  transition: 0.3s;
  margin: 0 10px;
}
.btn:hover { background: white; color: var(--purple); }

/* SEKCIE */
section {
  padding: 80px 60px;
  max-width: 1200px;
  margin: 0 auto;
  opacity: 0;
  transform: translateY(40px);
  transition: all 0.8s ease-out;
}
section.visible {
  opacity: 1;
  transform: translateY(0);
}

h2 {
  font-family: 'Poppins', sans-serif;
  font-weight: 700;
  font-size: 1.8rem;
  margin-bottom: 25px;
  color: var(--light-green);
}
body.light h2 { color: var(--green); }

.cards {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(260px, 1fr));
  gap: 25px;
}

.card {
  background: rgba(255,255,255,0.08);
  padding: 25px;
  border-radius: 15px;
  transition: 0.3s;
}
.card:hover {
  background: rgba(255,255,255,0.15);
  transform: translateY(-5px);
}
body.light .card {
  background: rgba(0,0,0,0.05);
}
body.light .card:hover {
  background: rgba(0,0,0,0.1);
}

/* FOOTER */
footer {
  text-align: center;
  padding: 40px 20px;
  background: rgba(0,0,0,0.7);
  color: #bbb;
  font-size: 0.9rem;
  margin-top: 60px;
  transition: background 0.5s;
}
body.light footer {
  background: rgba(255,255,255,0.8);
  color: #444;
}