:root {
    --bg-color: #0f172a;
    --card-bg: rgba(30, 41, 59, 0.7);
    --card-border: rgba(255, 255, 255, 0.1);
    --text-primary: #f8fafc;
    --text-secondary: #94a3b8;
    --accent-color: #3b82f6;
    --accent-hover: #60a5fa;
    --correct-bg: rgba(34, 197, 94, 0.1);
    --correct-text: #4ade80;
    --explanation-bg: rgba(245, 158, 11, 0.1);
    --explanation-text: #fbbf24;
    --monkey-bg: rgba(217, 70, 239, 0.1);
    --monkey-border: rgba(217, 70, 239, 0.2);
    --monkey-text: #e879f9;
}

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

body {
    font-family: 'Inter', sans-serif;
    background-color: var(--bg-color);
    color: var(--text-primary);
    display: flex;
    min-height: 100vh;
    background-image: 
        radial-gradient(circle at 15% 50%, rgba(59, 130, 246, 0.15), transparent 25%),
        radial-gradient(circle at 85% 30%, rgba(139, 92, 246, 0.15), transparent 25%);
}

.sidebar {
    width: 250px;
    background: rgba(15, 23, 42, 0.8);
    backdrop-filter: blur(10px);
    border-right: 1px solid var(--card-border);
    padding: 2rem 1rem;
    display: flex;
    flex-direction: column;
    position: fixed;
    height: 100vh;
}

.sidebar h2 {
    font-size: 1.25rem;
    margin-bottom: 1.5rem;
    color: var(--text-primary);
}

.sidebar ul {
    list-style: none;
    flex: 1;
    overflow-y: auto;
    padding-right: 0.5rem; /* Hely a görgetősávnak */
}

/* Egyedi stílus a görgetősávnak a dark mode-hoz */
.sidebar ul::-webkit-scrollbar {
    width: 6px;
}
.sidebar ul::-webkit-scrollbar-track {
    background: rgba(255, 255, 255, 0.05);
    border-radius: 4px;
}
.sidebar ul::-webkit-scrollbar-thumb {
    background: rgba(255, 255, 255, 0.2);
    border-radius: 4px;
}
.sidebar ul::-webkit-scrollbar-thumb:hover {
    background: rgba(255, 255, 255, 0.3);
}

.sidebar li {
    padding: 0.75rem 1rem;
    margin-bottom: 0.5rem;
    border-radius: 0.5rem;
    cursor: pointer;
    transition: all 0.2s ease;
    color: var(--text-secondary);
}

.sidebar li:hover {
    background: rgba(255, 255, 255, 0.05);
    color: var(--text-primary);
}

.sidebar li.active {
    background: var(--accent-color);
    color: white;
}

.stats {
    margin-top: auto;
    padding-top: 1rem;
    border-top: 1px solid var(--card-border);
    font-size: 0.875rem;
    color: var(--text-secondary);
}

.main-content {
    flex: 1;
    margin-left: 250px;
    padding: 3rem;
}

header {
    margin-bottom: 3rem;
}

header h1 {
    font-size: 2.5rem;
    font-weight: 800;
    margin-bottom: 0.5rem;
    background: linear-gradient(to right, #60a5fa, #c084fc);
    -webkit-background-clip: text;
    background-clip: text;
    -webkit-text-fill-color: transparent;
}

header p {
    color: var(--text-secondary);
    font-size: 1.1rem;
}

.cards-container {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(350px, 1fr));
    gap: 2rem;
}

.card {
    background: var(--card-bg);
    border: 1px solid var(--card-border);
    border-radius: 1rem;
    padding: 1.5rem;
    backdrop-filter: blur(10px);
    transition: transform 0.3s ease, box-shadow 0.3s ease;
    display: flex;
    flex-direction: column;
}

.card:hover {
    transform: translateY(-5px);
    box-shadow: 0 10px 25px rgba(0, 0, 0, 0.5);
    border-color: rgba(255, 255, 255, 0.2);
}

.card.known {
    border-color: rgba(34, 197, 94, 0.4);
    opacity: 0.6;
}

.card-header {
    display: flex;
    justify-content: space-between;
    align-items: flex-start;
    margin-bottom: 1rem;
}

.card-category {
    font-size: 0.75rem;
    text-transform: uppercase;
    letter-spacing: 0.05em;
    color: var(--accent-hover);
    margin-bottom: 0;
}

.btn-known {
    background: none;
    border: 1px solid var(--card-border);
    color: var(--text-secondary);
    border-radius: 50%;
    width: 30px;
    height: 30px;
    display: flex;
    align-items: center;
    justify-content: center;
    cursor: pointer;
    transition: all 0.2s ease;
    font-size: 0.9rem;
    flex-shrink: 0;
}

.btn-known:hover {
    background: rgba(255, 255, 255, 0.1);
    color: var(--text-primary);
}

.btn-known.active {
    background: rgba(34, 197, 94, 0.2);
    border-color: rgba(34, 197, 94, 0.5);
    color: #4ade80;
}

.card-question {
    font-size: 1.125rem;
    font-weight: 600;
    line-height: 1.5;
    margin-bottom: 1.5rem;
    flex: 1;
}

.card-btn {
    background: rgba(255, 255, 255, 0.05);
    border: 1px solid rgba(255, 255, 255, 0.1);
    color: var(--text-primary);
    padding: 0.75rem 1rem;
    border-radius: 0.5rem;
    font-family: 'Inter', sans-serif;
    font-size: 0.875rem;
    font-weight: 600;
    cursor: pointer;
    transition: all 0.2s ease;
    width: 100%;
    margin-bottom: 0.75rem;
}

.card-btn:hover {
    background: rgba(255, 255, 255, 0.1);
}

.monkey-btn {
    border-color: var(--monkey-border);
    color: var(--monkey-text);
}

.monkey-btn:hover {
    background: var(--monkey-bg);
}

.card-answer, .card-explanation, .card-monkey-brain {
    display: none;
    margin-top: 1rem;
    padding: 1rem;
    border-radius: 0.5rem;
    font-size: 0.9rem;
    line-height: 1.6;
}

.card-answer {
    background: var(--correct-bg);
    color: var(--correct-text);
    border: 1px solid rgba(34, 197, 94, 0.2);
}

.card-explanation {
    background: var(--explanation-bg);
    color: var(--text-primary);
    border: 1px solid rgba(245, 158, 11, 0.2);
}

.card-explanation strong {
    color: var(--explanation-text);
}

.card-monkey-brain {
    background: var(--monkey-bg);
    color: var(--text-primary);
    border: 1px solid var(--monkey-border);
}

.card-monkey-brain strong {
    color: var(--monkey-text);
}

.show {
    display: block;
    animation: fadeIn 0.4s ease forwards;
}

@keyframes fadeIn {
    from { opacity: 0; transform: translateY(-10px); }
    to { opacity: 1; transform: translateY(0); }
}

/* --- Reszponzivitás (Mobil nézet javítása Safari/iPhone esetén) --- */
@media (max-width: 768px) {
    body {
        flex-direction: column;
    }
    
    .sidebar {
        position: relative;
        width: 100%;
        height: auto;
        border-right: none;
        border-bottom: 1px solid var(--card-border);
        padding: 1.5rem 1rem;
    }
    
    .sidebar ul {
        display: flex;
        flex-wrap: wrap;
        gap: 0.5rem;
        max-height: 200px;
        overflow-y: auto;
        padding-right: 0;
    }
    
    .sidebar li {
        margin-bottom: 0;
        padding: 0.5rem 0.75rem;
        font-size: 0.85rem;
        flex: 1 1 auto;
        text-align: center;
        border: 1px solid rgba(255, 255, 255, 0.1);
    }
    
    .main-content {
        margin-left: 0;
        padding: 1.5rem 1rem;
    }
    
    header h1 {
        font-size: 1.75rem;
    }

    .cards-container {
        grid-template-columns: 1fr;
        gap: 1.5rem;
    }
    
    .filter-controls {
        margin-top: 1.5rem;
        text-align: center;
        display: flex;
        justify-content: center;
    }
}