html,body{
  max-width:100%;
  overflow-x:hidden;
}

header,section,footer{
  width:100%;
}

.features>*,.classes-section>*,footer>*{
  max-width:1200px;
  margin-left:auto;
  margin-right:auto;
  padding-left:1.5rem;
  padding-right:1.5rem;
}

:root{
  --primary:#8e44ad;
  --primary-dark:#6c3483;
  --secondary:#e74c3c;
  --accent:#f39c12;
  --text-dark:#2c3e50;
  --text-light:#6b7280;
  --bg-gradient:linear-gradient(135deg,#fdfbfd 0%,#f4ecf7 100%);
  --glass:rgba(255,255,255,.9);
  --shadow-lg:0 25px 60px rgba(142,68,173,.18);
  --shadow-md:0 12px 30px rgba(142,68,173,.12);
  --radius-xl:28px;
}

*{
  margin:0;
  padding:0;
  box-sizing:border-box;
  font-family:'Poppins',sans-serif;
  scroll-behavior:smooth;
}

body{
  background:var(--bg-gradient);
  color:var(--text-dark);
  overflow-x:hidden;
  line-height:1.7;
}

a{
  text-decoration:none;
  color:inherit;
  transition:all .3s ease;
}

ul{
  list-style:none;
}

/* ---------------- HEADER ---------------- */

header{
  background:rgba(255,255,255,.96);
  backdrop-filter:blur(14px);
  padding:0 5%;
  display:flex;
  justify-content:space-between;
  align-items:center;
  box-shadow:0 6px 25px rgba(0,0,0,.04);
  position:sticky;
  top:0;
  z-index:1000;
  height:80px;
}

.logo{
  font-size:1.7rem;
  font-weight:800;
  background:linear-gradient(45deg,var(--primary),#c0392b);
  background-clip:text;
  -webkit-background-clip:text;
  -webkit-text-fill-color:transparent;
  display:flex;
  align-items:center;
  gap:10px;
}

.logo-symbol{
  font-size:1.5rem;
  color:var(--primary);
  -webkit-text-fill-color:initial;
}

nav ul{
  display:flex;
  gap:2rem;
  align-items:center;
}

nav ul li a{
  font-weight:500;
  font-size:.95rem;
  color:var(--text-dark);
  position:relative;
}

nav ul li a:hover,
nav ul li a.active{
  color:var(--primary);
}

nav ul li a::after{
  content:'';
  position:absolute;
  bottom:-6px;
  left:0;
  width:0;
  height:2px;
  background:var(--primary);
  transition:width .3s;
}

nav ul li a:hover::after{
  width:100%;
}

.nav-btn{
  background:linear-gradient(135deg,var(--primary),#b24ac7);
  color:white!important;
  padding:10px 22px;
  border-radius:999px;
  box-shadow:0 10px 25px rgba(142,68,173,.35);
}

.nav-btn:hover{
  background:linear-gradient(135deg,var(--primary-dark),#9229a8);
  transform:translateY(-2px);
}

.nav-btn::after{display:none;}

.mobile-toggle{
  display:none;
  font-size:1.6rem;
  color:var(--text-dark);
  cursor:pointer;
}

/* ---------------- FOOTER ---------------- */

footer{
  background:#0f0f0f;
  color:#ecf0f1;
  padding:5rem 0 2rem;
  margin-top:5rem;
}

.footer-content{
  display:grid;
  grid-template-columns:2fr 1fr 1fr 1fr;
  gap:3rem;
  padding-bottom:3rem;
  border-bottom:1px solid #333;
}

.footer-section h3{
  color:white;
  margin-bottom:1.5rem;
  font-size:1.1rem;
}

.footer-links li{
  margin-bottom:12px;
}

.footer-links a{
  color:#bbb;
  font-size:.92rem;
  transition:.3s;
}

.footer-links a:hover{
  color:var(--primary);
  padding-left:6px;
}

.footer-logo{
  display:flex;
  align-items:center;
  gap:10px;
  margin-bottom:1rem;
  font-size:1.7rem;
  font-weight:800;
  color:white;
}

.footer-bottom{
  display:flex;
  justify-content:space-between;
  align-items:center;
  margin-top:2rem;
  color:#777;
  font-size:.85rem;
  flex-wrap:wrap;
  gap:1rem;
}

/* ---------------- DARK MODE ---------------- */

body.dark{
  background:#0b0b10;
  color:#e5e7eb;
}

body.dark header{
  background:rgba(20,20,30,.95);
}

body.dark section{
  background:transparent;
}

body.dark .class-card,
body.dark .feature-card,
body.dark .big-card{
  background:#161622;
  color:#f3f4f6;
  box-shadow:0 20px 40px rgba(0,0,0,.6);
}

/* Floating dark button (bottom-left) */
.dark-toggle{
  position:fixed;
  bottom:25px;
  left:25px;
  width:52px;
  height:52px;
  border-radius:50%;
  background:linear-gradient(135deg,#8e44ad,#c0392b);
  color:white;
  border:none;
  box-shadow:0 12px 30px rgba(142,68,173,.5);
  cursor:pointer;
  z-index:2000;
  display:flex;
  align-items:center;
  justify-content:center;
  font-size:1.2rem;
  transition:.3s;
}

.dark-toggle:hover{
  transform:scale(1.08) rotate(10deg);
}

/* ---------------- RESPONSIVE ---------------- */

@media (max-width:992px){
  header{
    height:70px;
    padding:0 1rem;
  }

  .mobile-toggle{display:block;}

  nav{
    position:absolute;
    top:70px;
    left:0;
    width:100%;
    background:rgba(255,255,255,.98);
    backdrop-filter:blur(20px);
    padding:1.5rem 0;
    box-shadow:0 20px 40px rgba(0,0,0,.1);
    display:none;
    flex-direction:column;
    align-items:center;
  }

  nav.active{
    display:flex;
    animation:slideDownMenu .4s ease forwards;
  }

  nav ul{
    flex-direction:column;
    gap:1.5rem;
  }

  @keyframes slideDownMenu{
    from{opacity:0;transform:translateY(-20px)}
    to{opacity:1;transform:translateY(0)}
  }

  .footer-content{
    grid-template-columns:1fr 1fr;
    padding:0 1rem 3rem;
  }

  .footer-bottom{
    padding:0 1rem;
    flex-direction:column;
    text-align:center;
  }
}

@media (max-width:600px){
  .footer-content{
    grid-template-columns:1fr;
  }
}

.dark-float-btn {
    position: fixed;
    left: 20px;
    bottom: 20px;
    width: 55px;
    height: 55px;
    border-radius: 50%;
    background: linear-gradient(135deg, #7B1FA2, #E91E63);
    color: #fff;
    border: none;
    font-size: 1.3rem;
    cursor: pointer;
    box-shadow: 0 8px 25px rgba(0,0,0,.3);
    z-index: 9999;
}