/* --- Solver Page Specific Styles --- */

/* حاوية المحتوى الرئيسية لصفحة الحل */
.solver-container {
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: 20px; 
    padding: 20px;
    max-width: 420px;
    width: 100%;
    margin: 0 auto 20px auto;
    box-sizing: border-box;
}

/* عنوان الصفحة والوصف */
.solver-header {
    text-align: center;
    width: 100%;
    padding: 20px 15px 0 15px;
    box-sizing: border-box;
}
.solver-header h1 {
    margin-bottom: 10px;
    font-size: 2rem;
}
.solver-header p {
    font-size: 1.1rem;
    color: #666;
    max-width: 930px;
    margin: 0 auto;
}
.theme-dark .solver-header p {
    color: var(--note-color-dark);
}
.theme-paper .solver-header p {
    color: var(--text-color-paper);
}


/* تعديل على الشبكة لجعل الخلايا قابلة للإدخال */
.solver-grid {
    width: 100%;
    max-width: 500px;
    aspect-ratio: 1 / 1;
    display: grid;
    grid-template-columns: repeat(9, 1fr);
    border: 3px solid #333; /* الإطار الخارجي السميك */
}
.theme-dark .solver-grid { border-color: var(--text-color-dark); }
.theme-paper .solver-grid { border-color: var(--text-color-paper); }


/* تصميم خانات الإدخال داخل الشبكة لتبدو كخلايا سودوكو */
.solver-cell {
    width: 100%;
    height: 100%;
    box-sizing: border-box;
    /* الخطوط الداخلية الصغيرة (تبقى كما هي رفيعة وباهتة) */
    border: 1px solid var(--border-color-light); 
    background-color: transparent;
    text-align: center;
    font-size: clamp(14px, 4vw, 22px);
    font-family: 'Roboto', sans-serif;
    color: var(--user-num-color-light);
    font-weight: bold;
    -moz-appearance: textfield;
    text-transform: uppercase;
}
.solver-cell::-webkit-outer-spin-button,
.solver-cell::-webkit-inner-spin-button {
    -webkit-appearance: none;
    margin: 0;
}
.theme-dark .solver-cell {
    border-color: var(--border-color-dark);
    color: var(--user-num-color-dark);
}
.theme-paper .solver-cell {
    border-color: var(--border-color-paper);
    color: var(--user-num-color-paper);
}

/* --- START: 9x9 Grid Borders (Updated for clarity) --- */

/* الخطوط العمودية الفاصلة للمربعات الكبيرة (كل 3 خلايا) */
.solver-page:not(.solver-16x16-page) .solver-cell:nth-child(3n) { 
    border-right: 2px solid #333; /* لون داكن وسمك واضح */
}
/* إعادة ضبط الخلية الأخيرة في الصف حتى لا تتضارب مع الإطار الخارجي */
.solver-page:not(.solver-16x16-page) .solver-cell:nth-child(9n) { 
    border-right: 1px solid var(--border-color-light); 
}

/* الخطوط الأفقية الفاصلة للمربعات الكبيرة (بعد الصف 3 والصف 6) */
.solver-page:not(.solver-16x16-page) .solver-cell:nth-of-type(n+19):nth-of-type(-n+27),
.solver-page:not(.solver-16x16-page) .solver-cell:nth-of-type(n+46):nth-of-type(-n+54) { 
    border-bottom: 2px solid #333; /* لون داكن وسمك واضح */
}

/* دعم الثيم الليلي والورقي للخطوط السميكة الجديدة */
.theme-dark .solver-page:not(.solver-16x16-page) .solver-cell:nth-child(3n),
.theme-dark .solver-page:not(.solver-16x16-page) .solver-cell:nth-of-type(n+19):nth-of-type(-n+27),
.theme-dark .solver-page:not(.solver-16x16-page) .solver-cell:nth-of-type(n+46):nth-of-type(-n+54) {
    border-color: var(--text-color-dark);
}
.theme-dark .solver-page:not(.solver-16x16-page) .solver-cell:nth-child(9n) {
     border-right: 1px solid var(--border-color-dark);
}

.theme-paper .solver-page:not(.solver-16x16-page) .solver-cell:nth-child(3n),
.theme-paper .solver-page:not(.solver-16x16-page) .solver-cell:nth-of-type(n+19):nth-of-type(-n+27),
.theme-paper .solver-page:not(.solver-16x16-page) .solver-cell:nth-of-type(n+46):nth-of-type(-n+54) {
    border-color: var(--text-color-paper);
}
.theme-paper .solver-page:not(.solver-16x16-page) .solver-cell:nth-child(9n) {
     border-right: 1px solid var(--border-color-paper);
}
/* --- END: 9x9 Grid Borders --- */


/* تمييز الخلية التي تم حلها بواسطة الخوارزمية */
.solver-cell.solved-cell {
    color: var(--fixed-num-color-light);
    font-weight: normal;
    background-color: rgba(46, 204, 113, 0.1);
}
.theme-dark .solver-cell.solved-cell {
    color: var(--text-color-dark);
    background-color: rgba(39, 174, 96, 0.2);
}
.theme-paper .solver-cell.solved-cell {
    color: var(--fixed-num-color-paper);
    background-color: rgba(133, 153, 0, 0.1);
}

/* تمييز الخلية التي بها خطأ في الإدخال الأولي */
.solver-cell.error-cell {
    background-color: var(--error-bg-light);
    animation: shake 0.5s;
}
.theme-dark .solver-cell.error-cell {
    background-color: var(--error-bg-dark);
}
.theme-paper .solver-cell.error-cell {
    background-color: var(--error-bg-paper);
}

/* حاوية أزرار التحكم */
.solver-controls {
    display: flex;
    gap: 15px;
    width: 100%;
    max-width: 500px;
    justify-content: center;
}

/* تصميم الأزرار */
.solver-button {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    gap: 8px;
    padding: 10px 20px;
    font-size: 1rem;
    font-weight: bold;
    border-radius: 8px;
    border: none;
    cursor: pointer;
    transition: transform 0.2s, box-shadow 0.2s, background-color 0.2s;
    flex-grow: 1;
}

.solver-button:disabled {
    cursor: not-allowed;
    background-color: #bdc3c7;
    box-shadow: 0 4px #95a5a6;
}

.solver-button:active {
    transform: scale(0.98);
}

/* تصميم زر الحل */
.solve-button {
    background-color: #2ecc71;
    color: white;
    box-shadow: 0 4px #27ae60;
}
.solve-button:hover:not(:disabled) {
    background-color: #35d679;
}
.solve-button:active:not(:disabled) {
    box-shadow: 0 2px #27ae60;
}

/* تصميم زر المسح */
.clear-button {
    background-color: #e74c3c;
    color: white;
    box-shadow: 0 4px #c0392b;
}
.clear-button:hover {
    background-color: #ec5e4f;
}
.clear-button:active {
    box-shadow: 0 2px #c0392b;
}


/* --- START: Solver Number Pad Styles --- */
.solver-numpad {
    display: flex;
    justify-content: center;
    gap: 2.5px;
    width: 100%;
    max-width: 500px;
    margin-top: 1px;
    flex-wrap: wrap; 
}

.num-button {
    width: 40px;
    height: 40px;
    font-size: 18px;
    font-weight: bold;
    border-radius: 5px;
    border: 1px solid var(--border-color-light);
    cursor: pointer;
    background-color: var(--grid-bg-light);
    color: var(--text-color-light);
    transition: background-color 0.2s, transform 0.1s;
    text-transform: uppercase;
}

.theme-dark .num-button {
    background-color: #4a617a;
    color: var(--text-color-dark);
    border-color: var(--border-color-dark);
}
.theme-paper .num-button {
    background-color: var(--secondary-color-paper);
    color: var(--text-color-paper);
    border-color: var(--border-color-paper);
}

.num-button:hover {
    background-color: var(--highlight-color-light);
}
.theme-dark .num-button:hover {
    background-color: var(--highlight-color-dark);
}
.theme-paper .num-button:hover {
    background-color: var(--highlight-color-paper);
}

.num-button:active {
    transform: scale(0.95);
}

/* --- START: 16x16 Solver Styles (Updated Borders) --- */
.solver-16x16-page .solver-container {
    max-width: 600px;
}

.solver-16x16-page .solver-grid {
    max-width: 600px;
    grid-template-columns: repeat(16, 1fr);
}

.solver-16x16-page .solver-cell {
    font-size: clamp(10px, 2.5vw, 15px);
}

/* الخطوط العمودية السميكة لـ 16x16 (كل 4 خلايا) */
.solver-16x16-page .solver-cell:nth-child(4n) { 
    border-right: 2px solid #333; 
}
.solver-16x16-page .solver-cell:nth-child(16n) { 
    border-right: 1px solid var(--border-color-light); 
}

/* الخطوط الأفقية السميكة لـ 16x16 (بعد صف 4، 8، 12) */
.solver-16x16-page .solver-cell:nth-of-type(n+49):nth-of-type(-n+64),
.solver-16x16-page .solver-cell:nth-of-type(n+113):nth-of-type(-n+128),
.solver-16x16-page .solver-cell:nth-of-type(n+177):nth-of-type(-n+192)
{
    border-bottom: 2px solid #333;
}

/* دعم الثيمات لـ 16x16 */
.theme-dark .solver-16x16-page .solver-cell:nth-child(4n),
.theme-dark .solver-16x16-page .solver-cell:nth-of-type(n+49):nth-of-type(-n+64),
.theme-dark .solver-16x16-page .solver-cell:nth-of-type(n+113):nth-of-type(-n+128),
.theme-dark .solver-16x16-page .solver-cell:nth-of-type(n+177):nth-of-type(-n+192) {
    border-color: var(--text-color-dark);
}
.theme-dark .solver-16x16-page .solver-cell:nth-child(16n) {
    border-right: 1px solid var(--border-color-dark);
}

.theme-paper .solver-16x16-page .solver-cell:nth-child(4n),
.theme-paper .solver-16x16-page .solver-cell:nth-of-type(n+49):nth-of-type(-n+64),
.theme-paper .solver-16x16-page .solver-cell:nth-of-type(n+113):nth-of-type(-n+128),
.theme-paper .solver-16x16-page .solver-cell:nth-of-type(n+177):nth-of-type(-n+192) {
    border-color: var(--text-color-paper);
}
.theme-paper .solver-16x16-page .solver-cell:nth-child(16n) {
    border-right: 1px solid var(--border-color-paper);
}


.solver-16x16-page .solver-numpad {
    max-width: 600px;
    gap: 6px;
}
.solver-16x16-page .num-button {
    width: 36px;
    height: 36px;
    font-size: 14px; 
    padding: 2px; 
}
/* --- END: 16x16 Solver Styles --- */


/* تعديلات للشاشات الصغيرة */
@media (max-width: 768px) {
    .solver-container {
        padding: 10px;
        gap: 15px;
        max-width: 100%;
    }

    .solver-header h1 {
        font-size: 1.8rem;
    }
    
    .solver-header p {
        font-size: 0.95rem;
    }

    .solver-numpad {
        display: flex;
        flex-wrap: wrap;
        gap: 6px;
        justify-content: center;
    }

    .num-button {
        flex: 1 1 40px;
        max-width: 45px;
        height: 48px;
        font-size: 20px;
    }

    .solver-16x16-page .num-button {
       flex: 1 1 38px;
       max-width: 42px;
       height: 42px;
       font-size: 16px;
    }

    .solver-controls {
        flex-direction: column;
        gap: 12px;
        width: 100%;
    }
    
    .solver-button {
        width: 100%;
        padding: 14px;
        font-size: 1.1rem;
    }
}

/* --- END: Solver Number Pad Styles --- */


/* --- START: Enhanced Solver Description Styles --- */
.solver-description {
    max-width: 800px;
    margin: 40px auto;
    padding: 30px 35px;
    line-height: 1.7;
    color: #444;
    background-color: #fcfcfc;
    border-radius: 12px;
    border: 1px solid #e9e9e9;
    box-shadow: 0 4px 20px rgba(0, 0, 0, 0.06);
    position: relative;
    overflow: hidden;
}

.solver-description::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 6px;
    background: linear-gradient(90deg, #2ecc71, #27ae60);
}

.theme-dark .solver-description {
    color: var(--note-color-dark);
    background-color: #2c3e50;
    border-color: #3e5369;
    box-shadow: 0 4px 25px rgba(0, 0, 0, 0.2);
}
.theme-dark .solver-description::before {
     background: linear-gradient(90deg, #2ecc71, #35d679);
}

.theme-paper .solver-description {
    color: var(--text-color-paper);
    background-color: #fdf6e3;
    border-color: #eee8d5;
    box-shadow: 0 2px 10px rgba(0,0,0,0.07);
}
.theme-paper .solver-description::before {
    background: #b58900;
}

.solver-description h2 {
    font-size: 1.9rem;
    text-align: center;
    margin-bottom: 20px;
    color: #333;
    font-weight: 700;
}

.solver-description h3 {
    font-size: 1.5rem;
    margin-top: 30px;
    margin-bottom: 15px;
    padding-bottom: 8px;
    color: #333;
    border: none;
    position: relative;
}

.solver-description h3::after {
    content: '';
    position: absolute;
    bottom: 0;
    left: 0;
    width: 50px;
    height: 3px;
    background-color: #2ecc71;
    border-radius: 2px;
}

.theme-dark .solver-description h2,
.theme-dark .solver-description h3 {
    color: var(--text-color-dark);
}
.theme-dark .solver-description h3::after {
    background-color: #2ecc71;
}

.theme-paper .solver-description h2,
.theme-paper .solver-description h3 {
    color: var(--text-color-paper);
}
.theme-paper .solver-description h3::after {
    background-color: #b58900;
}

.solver-description p {
    font-size: 1.05rem;
    margin-bottom: 15px;
}

.solver-description ul {
    list-style-type: none;
    padding-left: 0;
    margin-bottom: 15px;
}

.solver-description li {
    margin-bottom: 12px;
    padding-left: 28px;
    position: relative;
    font-size: 1.05rem;
}

.solver-description li::before {
    content: '✓';
    position: absolute;
    left: 0;
    top: 1px;
    color: #27ae60;
    font-weight: bold;
    font-size: 1.2rem;
}

.theme-dark .solver-description li::before {
    color: #2ecc71;
}

.theme-paper .solver-description li::before {
    content: '»';
    color: #b58900;
}

@media (max-width: 768px) {
    .solver-description {
        margin: 30px 10px;
        padding: 25px 20px;
    }

    .solver-description h2 {
        font-size: 1.6rem;
    }
    .solver-description h3 {
        font-size: 1.3rem;
    }
    .solver-description p, .solver-description li {
        font-size: 1rem;
    }
}

/* --- END: Enhanced Solver Description Styles --- */


.solver-page #stats-btn,
.solver-page #mobile-stats-btn {
    display: none;
}

/* RTL Support */
html[lang="ar"] body [dir="rtl"] .solver-description ul li,
html[lang="ar"] body .solver-description ul li {
    position: relative !important;
    list-style: none !important; 
    text-align: right !important;
    padding-left: 0 !important;
    padding-right: 40px !important; 
}

html[lang="ar"] body [dir="rtl"] .solver-description ul li::before,
html[lang="ar"] body .solver-description ul li::before {
    position: absolute !important;
    top: 50% !important; 
    transform: translateY(-50%) !important; 
    left: auto !important; 
    right: 10px !important; 
}