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

/* Background aquarium */
body{
  display:flex;
  flex-direction:column; /* FIX: vertikal */
  min-height:100vh;      /* FIX: full tinggi layar */
  background: linear-gradient(to bottom, #0d47a1, #1976d2, #42a5f5);
  color:#e3f2fd;
  overflow-x:hidden;
  position:relative;
}

/* Efek gelembung */
body::before,
body::after{
  content:"";
  position:absolute;
  bottom:-100px;
  width:100%;
  height:100%;
  pointer-events:none;
  background-image:
    radial-gradient(circle, rgba(255,255,255,0.6) 2px, transparent 3px),
    radial-gradient(circle, rgba(255,255,255,0.4) 3px, transparent 4px),
    radial-gradient(circle, rgba(255,255,255,0.3) 1.5px, transparent 3px);
  background-size: 100px 100px, 150px 150px, 80px 80px;
  animation: bubblesUp 20s linear infinite;
  z-index:0;
}

body::after{
  animation-duration: 30s;
  opacity:0.7;
}

/* animasi */
@keyframes bubblesUp{
  from{ transform: translateY(0); }
  to{ transform: translateY(-1000px); }
}

/* Sidebar */
.sidebar{
  width:220px;
  height:100vh;
  background: rgba(13,71,161,0.9);
  color:#ffffff;
  padding:20px;
  position:fixed;
  transition:0.3s;
  z-index:1000;
  backdrop-filter: blur(6px);
}

.sidebar h2{
  margin-bottom:20px;
}

.sidebar a{
  display:block;
  color:#e3f2fd;
  text-decoration:none;
  margin:10px 0;
  padding:10px;
  border-radius:5px;
  transition:0.2s;
}

.sidebar a:hover{
  background:rgba(255,255,255,0.2);
  color:#ffffff;
}

/* Main */
.main{
  margin-left:220px;
  width:calc(100% - 220px); /* FIX utama */
  padding:20px;
  position:relative;
  z-index:1;
  flex:1;

  max-width:1200px;   /* biar enak di layar besar */
  margin-right:auto;
}
.main p{
  line-height:1.6;
  max-width:800px; /* biar paragraf nyaman dibaca */
}
/* Topbar */
.topbar{
  display:flex;
  align-items:center;
  gap:10px;
  margin-bottom:20px;
}

.topbar h1{
  color:#ffffff;
  text-shadow:0 2px 5px rgba(0,0,0,0.4);
}

.topbar button{
  font-size:20px;
  cursor:pointer;
  background:rgba(255,255,255,0.2);
  border:none;
  color:#fff;
  padding:5px 10px;
  border-radius:5px;
}

/* Controls */
.controls{
  display:flex;
  flex-wrap:wrap;
  gap:10px;
  margin-bottom:15px;
}

.controls input, 
.controls select{
  padding:8px;
  border:none;
  border-radius:6px;
  background:rgba(255,255,255,0.9);
  color:#333;
  outline:none;
}

/* Catalog */
.catalog{
  display:grid;
  grid-template-columns:repeat(auto-fit,minmax(200px,1fr));
  gap:15px;
}

/* Card */
.card{
  background:rgba(255,255,255,0.95);
  border-radius:12px;
  box-shadow:0 4px 10px rgba(0,0,0,0.2);
  overflow:hidden;
  transition:0.2s;
}

.card:hover{
  transform:translateY(-5px);
}

.card img{
  width:100%;
  height:150px;
  object-fit:cover;
}

.card h3{
  padding:10px;
  color:#0d47a1;
}

.card p{
  padding:0 10px 10px;
  font-size:14px;
  color:#555;
}
.card h2,
.card h3{
  color:#0d47a1;
}

.card label{
  color:#0d47a1; /* biru gelap biar kontras */
  font-weight:bold;
}

/* Pagination */
.pagination{
  margin-top:20px;
  text-align:center;
}

.pagination button{
  padding:6px 12px;
  margin:3px;
  cursor:pointer;
  border:none;
  border-radius:5px;
  background:#1976d2;
  color:#fff;
  transition:0.2s;
}

.pagination button:hover{
  background:#42a5f5;
}

/* Footer */
.footer{
  background:#0d47a1;
  color:#fff;
  text-align:center;
  padding:15px;
  margin-top:40px;
}

/* Responsive */
@media(max-width:768px){
  .sidebar{left:-220px;}
  .sidebar.active{left:0;}
  .main{margin-left:0;}
}

input, button{
  border:none;
  border-radius:6px;
  outline:none;
}

button{
  background:#1976d2;
  color:#fff;
  cursor:pointer;
  transition:0.2s;
}

button:hover{
  background:#42a5f5;
}

.catalog .item h3,
.catalog .item p{
  color:#0d47a1;
}