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

body {
    background-color: #f1f5f9;
    color: #334155;
    display: flex;
    justify-content: center;
    align-items: center;
    min-height: 100vh;
    padding: 15px;
}

#app-container {
    background: white;
    width: 100%;
    max-width: 600px;
    border-radius: 12px;
    box-shadow: 0 4px 6px -1px rgba(0, 0, 0, 0.1), 0 2px 4px -1px rgba(0, 0, 0, 0.06);
    padding: 30px;
    text-align: center;
}

.screen { display: none; opacity: 0; transition: opacity 0.3s ease-in-out; }
.screen.active { display: block; opacity: 1; }

.main-title { color: #0f172a; font-size: 2.2rem; margin-bottom: 10px; font-weight: 600; }
.subtitle { font-size: 1rem; color: #64748b; margin-bottom: 30px; }
h2 { color: #1e293b; margin-bottom: 20px; font-size: 1.5rem; font-weight: 600; }

.subject-tag {
    font-size: 0.85rem;
    color: #ffffff;
    background: #3b82f6;
    padding: 4px 12px;
    border-radius: 4px;
    display: inline-block;
    margin-bottom: 20px;
    text-transform: uppercase;
    letter-spacing: 0.5px;
}

button {
    border: none;
    border-radius: 6px;
    padding: 14px 20px;
    font-size: 1rem;
    font-weight: 600;
    cursor: pointer;
    transition: background-color 0.2s, transform 0.1s;
    width: 100%;
    margin-bottom: 12px;
}

.btn-primary { background: #0f172a; color: white; }
.btn-primary:hover { background: #1e293b; }

.grid-subjects { display: grid; grid-template-columns: 1fr; gap: 12px; margin-bottom: 20px; }

.btn-subject { color: white; background: #334155; }
.btn-subject:hover { background: #475569; }

.grid-options { display: grid; gap: 10px; margin-bottom: 20px; }

.btn-option {
    background: #f8fafc;
    color: #334155;
    border: 1px solid #cbd5e1;
    text-align: left;
    font-weight: 400;
}
.btn-option:hover { background: #f1f5f9; border-color: #94a3b8; }
.btn-option.correct { background: #dcfce7; color: #166534; border-color: #22c55e; }
.btn-option.wrong { background: #fee2e2; color: #991b1b; border-color: #ef4444; }

.btn-back { background: transparent; color: #64748b; border: 1px solid transparent; }
.btn-back:hover { background: #f1f5f9; color: #334155; }

.arabic-text {
    font-family: 'Amiri', serif !important;
    font-size: 1.5rem !important;
    direction: rtl;
    text-align: right;
}

.progress-bar {
    width: 100%; background: #e2e8f0; height: 6px; border-radius: 3px; margin-bottom: 20px; overflow: hidden;
}
#progress {
    height: 100%; background: #3b82f6; width: 0%; border-radius: 3px; transition: width 0.3s ease;
}

#feedback { font-size: 1.1rem; font-weight: 600; min-height: 25px; margin-top: 10px; }