:root {
  --bg-a: #fff8e7;
  --bg-b: #dff7ff;
  --card: #ffffff;
  --text: #1e293b;
  --muted: #475569;
  --primary: #ff7f50;
  --primary-hover: #ff6b3d;
  --success: #16a34a;
  --danger: #dc2626;
}

* {
  box-sizing: border-box;
}

body {
  margin: 0;
  min-height: 100vh;
  font-family: "Trebuchet MS", "Segoe UI", sans-serif;
  color: var(--text);
  background: radial-gradient(circle at 15% 20%, var(--bg-a), transparent 45%),
    radial-gradient(circle at 85% 10%, #e9ffe7, transparent 40%),
    linear-gradient(135deg, var(--bg-b), #fffaf0);
  display: flex;
  justify-content: center;
  align-items: center;
  overflow-x: hidden;
}

#confetti-container {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    pointer-events: none;
    z-index: 9999;
}

.container {
    background: var(--card);
    border-radius: 20px;
    box-shadow: 0 14px 30px rgba(30, 41, 59, 0.15);
    padding: 30px;
    text-align: center;
    border: 6px solid var(--primary);
    animation: borderRainbow 6s linear infinite;
    width: 90%;
    max-width: 1400px;
    margin: 20px;
}

@keyframes borderRainbow {
  0% { border-color: #ff7f50; }
  33% { border-color: #47b8ff; }
  66% { border-color: #4ade80; }
  100% { border-color: #ff7f50; }
}

h1, h2 {
    color: var(--primary);
    margin-top: 0;
}

p {
    color: var(--muted);
    font-size: 1.1em;
}

.game-area {
    display: flex;
    gap: 20px;
    margin: 20px auto;
    justify-content: center;
    align-items: flex-start;
    flex-wrap: wrap;
}

.pieces-container {
    width: 440px;
    min-height: 600px;
    border: 4px dashed #cbd5e1;
    background-color: #f1f5f9;
    display: flex;
    flex-wrap: wrap;
    gap: 10px;
    padding: 15px;
    align-content: flex-start;
    border-radius: 12px;
}

.board {
    display: grid;
    grid-template-columns: repeat(3, 200px);
    grid-template-rows: repeat(3, 200px);
    background-color: #f8fafc;
    border: 4px solid var(--text);
    width: 600px;
    height: 600px;
    box-sizing: content-box;
    border-radius: 10px;
    box-shadow: 0 10px 20px rgba(0,0,0,0.1);
}

.board-slot {
    width: 200px;
    height: 200px;
    border: 1px dashed #cbd5e1;
    box-sizing: border-box;
    position: relative; /* Agar piece bisa tumpang tindih mutlak di sini */
}

.piece {
    box-sizing: border-box;
    background-repeat: no-repeat;
    cursor: grab;
    filter: drop-shadow(2px 2px 3px rgba(0,0,0,0.5));
}

.pieces-container .piece {
    position: relative;
    margin: -10px; /* Tertumpuk sedikit biar muat di kotak samping */
    z-index: 1;
}

.pieces-container .piece:hover {
    z-index: 2;
}

.board-slot .piece {
    position: absolute;
    top: -20px; /* Offset dari tonjolan puzzle (offset = 20px) */
    left: -20px;
    z-index: 5;
}

.piece:active {
    cursor: grabbing;
    z-index: 999 !important; /* Di atas segalanya saat diseret */
}

.hidden {
    display: none;
}

#message {
    font-size: 1.5em;
    color: var(--primary);
    margin-bottom: 20px;
    font-weight: bold;
}

button {
    padding: 12px 24px;
    font-size: 1.1em;
    cursor: pointer;
    background-color: var(--primary);
    color: white;
    border: none;
    border-radius: 50px;
    transition: all 0.2s ease;
    margin: 5px;
    box-shadow: 0 4px 0 #cbd5e1;
}

button:hover {
    transform: translateY(2px);
    box-shadow: 0 2px 0 #cbd5e1;
    background-color: var(--secondary);
}

button:active {
    transform: translateY(4px);
    box-shadow: none;
}

.main-btn {
    font-size: 1.5em;
    padding: 15px 30px;
    background-color: var(--primary);
    box-shadow: 0 6px 0 #cbd5e1;
}
.main-btn:hover { 
    background-color: var(--secondary);
    transform: translateY(3px);
    box-shadow: 0 3px 0 #cbd5e1;
}
.main-btn:active {
    transform: translateY(6px);
    box-shadow: none;
}

.back-btn {
    background-color: #fca5a5;
    color: var(--text);
}
.back-btn:hover { background-color: #f87171; }

.image-grid {
    display: flex;
    justify-content: center;
    gap: 20px;
    flex-wrap: wrap;
}

.preview-card {
    cursor: pointer;
    padding: 10px;
    background: var(--bg);
    border: 3px solid var(--text);
    border-radius: 12px;
    transition: transform 0.2s, background-color 0.2s;
    width: 250px;
}

.preview-card:hover {
    transform: scale(1.05);
    border-color: var(--primary);
    background-color: #f1f5f9;
}

.preview-card img {
    width: 100%;
    height: 140px;
    object-fit: cover;
    border-radius: 8px;
    border: 2px dashed #cbd5e1;
}

.controls {
    margin-top: 20px;
}