*{
  box-sizing:border-box;
}

body{
  margin:0;
  font-family:Arial, Helvetica, sans-serif;
  background:#f3f4f6;
  color:#111;
}

.topbar{
  background:#232F3E;
  color:#fff;
  padding:16px 24px;
  display:flex;
  align-items:center;
  justify-content:space-between;
  gap:20px;
  flex-wrap:wrap;
}

.topbar-left{
  display:flex;
  align-items:center;
  gap:12px;
}

.logo-badge{
  background:#FF9900;
  color:#111;
  font-weight:800;
  font-size:14px;
  padding:8px 12px;
  border-radius:8px;
}

.site-title{
  font-size:20px;
  font-weight:700;
}

.nav-links{
  display:flex;
  gap:12px;
  flex-wrap:wrap;
}

.nav-links a{
  color:#fff;
  text-decoration:none;
  font-size:14px;
  opacity:.95;
}

.nav-links a:hover{
  opacity:1;
  text-decoration:underline;
}

.container{
  max-width:1100px;
  margin:30px auto;
  padding:0 16px;
}

.card{
  background:#fff;
  border-radius:14px;
  padding:24px;
  box-shadow:0 8px 24px rgba(0,0,0,.08);
  margin-bottom:20px;
}

.hero-title{
  margin:0 0 10px;
  font-size:30px;
  color:#232F3E;
}

.hero-text{
  margin:0;
  color:#444;
  line-height:1.6;
}

.grid{
  display:grid;
  grid-template-columns:repeat(3, 1fr);
  gap:18px;
}

.stat-card{
  background:#fff;
  border-radius:14px;
  padding:20px;
  box-shadow:0 8px 24px rgba(0,0,0,.08);
}

.stat-label{
  font-size:13px;
  color:#666;
  margin-bottom:8px;
}

.stat-value{
  font-size:28px;
  font-weight:800;
  color:#232F3E;
}

.section-title{
  font-size:24px;
  margin:0 0 16px;
  color:#232F3E;
}

.lesson-list{
  display:flex;
  flex-direction:column;
  gap:14px;
}

.lesson-item{
  border:1px solid #e6e6e6;
  border-radius:12px;
  padding:16px;
  display:flex;
  align-items:center;
  justify-content:space-between;
  gap:14px;
  flex-wrap:wrap;
}

.lesson-info h3{
  margin:0 0 6px;
  font-size:18px;
}

.lesson-info p{
  margin:0;
  color:#666;
  font-size:14px;
  line-height:1.5;
}

.btn{
  display:inline-block;
  background:#FF9900;
  color:#111;
  text-decoration:none;
  font-weight:800;
  padding:12px 18px;
  border-radius:10px;
  border:none;
  cursor:pointer;
  transition:.2s ease;
}

.btn:hover{
  transform:translateY(-1px);
  filter:brightness(1.03);
}

.btn-secondary{
  background:#232F3E;
  color:#fff;
}

.video-wrap{
  position:relative;
  width:100%;
  padding-bottom:56.25%;
  border-radius:14px;
  overflow:hidden;
  background:#000;
}

.video-wrap iframe{
  position:absolute;
  inset:0;
  width:100%;
  height:100%;
}

.login-wrap{
  min-height:100vh;
  display:flex;
  align-items:center;
  justify-content:center;
  padding:20px;
  background:linear-gradient(135deg,#f3f4f6,#e5e7eb);
}

.login-card{
  width:100%;
  max-width:420px;
  background:#fff;
  padding:28px;
  border-radius:16px;
  box-shadow:0 10px 30px rgba(0,0,0,.08);
}

.login-title{
  margin:0 0 8px;
  font-size:28px;
  color:#232F3E;
}

.login-subtitle{
  margin:0 0 20px;
  color:#666;
  line-height:1.5;
}

.form-group{
  margin-bottom:14px;
}

.form-group label{
  display:block;
  margin-bottom:8px;
  font-size:14px;
  font-weight:700;
  color:#333;
}

.form-group input{
  width:100%;
  padding:14px;
  border:1px solid #d7d7d7;
  border-radius:10px;
  font-size:15px;
  outline:none;
}

.form-group input:focus{
  border-color:#FF9900;
  box-shadow:0 0 0 3px rgba(255,153,0,.15);
}

.alert{
  background:#fff3cd;
  color:#7a5b00;
  border:1px solid #ffe69c;
  padding:12px 14px;
  border-radius:10px;
  margin-bottom:16px;
  font-size:14px;
}

.footer-note{
  font-size:12px;
  color:#777;
  margin-top:16px;
  line-height:1.5;
}

@media (max-width: 900px){
  .grid{
    grid-template-columns:1fr;
  }

  .hero-title{
    font-size:26px;
  }
}