:root {
    --bg-dark: #121212;
    --bg-panel: #1e1e1e;
    --primary: #3b82f6;
    --accent-x: #ef4444;
    --accent-o: #22c55e;
    --text-main: #ffffff;
    --text-muted: #94a3b8;
}

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

body {
    background-color: var(--bg-dark);
    color: var(--text-main);
    min-height: 100vh; /* Gunakan min-height agar bisa scroll jika layar pendek */
    display: flex;
    justify-content: center;
    align-items: center;
    overflow-x: hidden; /* Mencegah scroll horizontal */
}

/* --- TRANSITIONS & SCREENS --- */
.screen {
    position: absolute;
    width: 100%;
    height: 100%;
    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: center;
    padding: 20px; /* Tambahan padding agar konten tidak mepet tepi HP */
    transition: opacity 0.5s ease, transform 0.5s ease;
}

.hidden {
    opacity: 0;
    pointer-events: none;
    transform: scale(0.95);
    z-index: -1;
    display: none; /* Penting untuk mobile agar layout tidak tumpang tindih */
}

.active {
    opacity: 1;
    pointer-events: all;
    transform: scale(1);
    z-index: 1;
    display: flex; /* Kembalikan ke flex saat aktif */
}

/* --- MAIN MENU --- */
.title-container { text-align: center; margin-bottom: 30px; }
h1 { font-size: 2.5rem; line-height: 1.1; letter-spacing: 2px; text-transform: uppercase; }
.subtitle { color: var(--text-muted); margin-top: 10px; font-size: 1rem; }

.menu-controls { width: 100%; max-width: 400px; display: flex; flex-direction: column; gap: 15px; }

.level-selector { background: var(--bg-panel); padding: 15px; border-radius: 12px; }
.level-selector label { display: block; margin-bottom: 10px; color: var(--text-muted); font-size: 0.9rem; }
.level-buttons { display: flex; gap: 8px; }

.lvl-btn {
    flex: 1;
    background: transparent;
    border: 1px solid var(--text-muted);
    color: var(--text-muted);
    padding: 10px 5px; /* Padding lebih kecil untuk HP kecil */
    border-radius: 8px;
    cursor: pointer;
    transition: 0.3s;
    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: center;
}
.lvl-btn strong { font-size: 1.1rem; }
.lvl-btn span { font-size: 0.6rem; font-weight: normal; margin-top: 2px; text-align: center; }
.lvl-btn.active, .lvl-btn:hover { border-color: var(--primary); color: var(--primary); background: rgba(59, 130, 246, 0.1); }

.primary-btn {
    background: var(--primary); color: white; border: none; padding: 15px;
    font-size: 1.2rem; font-weight: bold; border-radius: 8px; cursor: pointer;
    box-shadow: 0 4px 15px rgba(59, 130, 246, 0.4); transition: transform 0.2s;
    width: 100%;
}
.primary-btn:active { transform: scale(0.98); }

.secondary-btn { background: transparent; border: 1px solid var(--text-muted); color: var(--text-muted); padding: 12px; border-radius: 8px; cursor: pointer; width: 100%; }

/* --- GAME SCREEN --- */
.game-header {
    width: 100%; max-width: 450px; display: flex; justify-content: space-between; align-items: center;
    margin-bottom: 15px;
}
.icon-btn { background: none; border: none; color: var(--text-muted); font-size: 0.9rem; cursor: pointer; padding: 10px; }

.game-info { text-align: center; }
#level-display { display: block; font-size: 0.75rem; color: var(--text-muted); }
#status-display { font-size: 1.2rem; font-weight: bold; }

.p-x { color: var(--accent-x); }
.p-o { color: var(--accent-o); }

/* BOARD RESPONSIVE */
.game-container {
    width: 100%;
    display: flex;
    justify-content: center;
}

.game-board {
    display: grid;
    gap: 8px;
    background: var(--bg-panel);
    padding: 10px;
    border-radius: 15px;
    
    /* KUNCI RESPONSIVE: */
    width: 100%;
    max-width: 400px; /* Batas lebar di desktop */
    aspect-ratio: 1 / 1; /* Pastikan selalu kotak sempurna */
}

.cell {
    background: var(--bg-dark);
    border-radius: 8px;
    display: flex; justify-content: center; align-items: center;
    cursor: pointer;
    user-select: none;
    width: 100%;
    height: 100%; /* Mengisi grid area sepenuhnya */
    
    /* Font size responsive: menyesuaikan dengan ukuran kotak */
    font-size: clamp(1.5rem, 8vw, 3rem); 
    font-weight: bold;
}
.cell:active { background: #2a2a2a; }

/* Animasi & Highlight */
.about-to-die span { opacity: 0.3; transform: scale(0.8); transition: 0.5s; }
.cell.win { background: rgba(255, 255, 255, 0.1); border: 2px solid var(--text-main); }
.cell span { animation: popIn 0.3s; }

@keyframes popIn { from { transform: scale(0); } to { transform: scale(1); } }

.queue-indicator { text-align: center; margin-top: 20px; color: var(--text-muted); font-size: 0.9rem; padding: 0 10px;}

/* --- MODAL --- */
.modal {
    position: fixed; top: 0; left: 0; width: 100%; height: 100%;
    background: rgba(0,0,0,0.85); z-index: 100;
    display: flex; justify-content: center; align-items: center;
    backdrop-filter: blur(5px);
    padding: 20px;
}
.modal-content { background: var(--bg-panel); padding: 25px; border-radius: 15px; max-width: 400px; width: 100%; }
.modal h2 { margin-bottom: 15px; color: var(--primary); font-size: 1.5rem;}
.modal ul { margin-left: 20px; margin-bottom: 20px; line-height: 1.5; font-size: 0.9rem; }
#btn-close-modal { width: 100%; padding: 12px; background: var(--primary); border: none; color: white; border-radius: 5px; font-weight: bold;}

/* --- MEDIA QUERY KHUSUS MOBILE KECIL --- */
@media (max-width: 400px) {
    h1 { font-size: 2rem; }
    .game-board { gap: 5px; padding: 5px; }
    .cell { border-radius: 4px; }
}