/* ============================================
   MODERN ROBOMIND DESIGN SYSTEM v2.0
   ============================================ */

/* CSS Variables & Enhanced Themes */
:root {
    /* Dark Theme (Default) */
    --bg-color: #0a0e27;
    --bg-secondary: #121a3a;
    --text-color: #f0f4f8;
    --text-secondary: #a0aec0;
    --text-tertiary: #718096;
    --panel-bg: rgba(20, 30, 60, 0.5);
    --panel-bg-light: rgba(30, 40, 80, 0.6);
    --border-color: #2d3a5c;
    --accent-color: #00d9ff;
    --accent-light: #33e5ff;
    --accent-glow: 0 0 30px rgba(0, 217, 255, 0.3);
    --accent-glow-strong: 0 0 50px rgba(0, 217, 255, 0.5);
    --success-color: #10b981;
    --success-light: #34d399;
    --warning-color: #f59e0b;
    --error-color: #ef4444;
    --error-light: #f87171;
    
    /* Typography */
    --font-main: 'Poppins', 'Tajawal', 'Inter', system-ui, sans-serif;
    --font-heading: 'Poppins', 'Tajawal', 'Inter', system-ui, sans-serif;
    --font-mono: 'JetBrains Mono', monospace;
    
    /* Spacing */
    --border-radius: 20px;
    --border-radius-lg: 28px;
    --btn-radius: 12px;
    --blur-amt: 20px;
    
    /* Transitions */
    --transition-fast: 0.15s cubic-bezier(0.4, 0, 0.2, 1);
    --transition-base: 0.3s cubic-bezier(0.4, 0, 0.2, 1);
    --transition-slow: 0.5s cubic-bezier(0.4, 0, 0.2, 1);
}

/* Light Theme */
body.theme-light {
    --bg-color: #f8fafc;
    --bg-secondary: #f1f5f9;
    --text-color: #1a202c;
    --text-secondary: #4a5568;
    --text-tertiary: #718096;
    --panel-bg: rgba(255, 255, 255, 0.9);
    --panel-bg-light: rgba(240, 244, 248, 0.8);
    --border-color: #e2e8f0;
    --accent-color: #0284c7;
    --accent-light: #0ea5e9;
    --accent-glow: 0 0 30px rgba(2, 132, 199, 0.2);
    --accent-glow-strong: 0 0 50px rgba(2, 132, 199, 0.3);
    --success-color: #059669;
    --success-light: #10b981;
    --warning-color: #d97706;
    --error-color: #dc2626;
    --error-light: #ef4444;
}

/* Kids Theme */
body.theme-kids {
    --bg-color: #fef08a;
    --bg-secondary: #fef3c7;
    --text-color: #78350f;
    --text-secondary: #92400e;
    --text-tertiary: #b45309;
    --panel-bg: rgba(255, 255, 255, 0.95);
    --panel-bg-light: rgba(254, 243, 199, 0.8);
    --border-color: #fcd34d;
    --accent-color: #ec4899;
    --accent-light: #f472b6;
    --accent-glow: 0 8px 0px rgba(236, 72, 153, 0.3);
    --accent-glow-strong: 0 12px 0px rgba(236, 72, 153, 0.4);
    --success-color: #16a34a;
    --success-light: #22c55e;
    --warning-color: #d97706;
    --error-color: #dc2626;
    --error-light: #f87171;
}

/* ============================================
   GLOBAL STYLES
   ============================================ */
* {
    box-sizing: border-box;
    margin: 0;
    padding: 0;
}

html {
    scroll-behavior: smooth;
}

body {
    background: linear-gradient(135deg, var(--bg-color) 0%, var(--bg-secondary) 100%);
    background-attachment: fixed;
    color: var(--text-color);
    font-family: var(--font-main);
    font-size: 16px;
    font-weight: 400;
    line-height: 1.6;
    min-height: 100vh;
    display: flex;
    flex-direction: column;
    transition: background-color var(--transition-base), color var(--transition-base);
    overflow-x: hidden;
}

/* Animated Background */
body::before {
    content: '';
    position: fixed;
    top: -20%;
    left: -10%;
    width: 50vw;
    height: 50vh;
    background: radial-gradient(circle, var(--accent-color) 0%, transparent 70%);
    opacity: 0.08;
    z-index: -1;
    pointer-events: none;
    animation: float 20s ease-in-out infinite;
}

body::after {
    content: '';
    position: fixed;
    bottom: -10%;
    right: -10%;
    width: 40vw;
    height: 40vh;
    background: radial-gradient(circle, var(--accent-color) 0%, transparent 70%);
    opacity: 0.05;
    z-index: -1;
    pointer-events: none;
    animation: float 25s ease-in-out infinite reverse;
}

body.theme-kids::before { opacity: 0.2; }
body.theme-kids::after { opacity: 0.15; }

#app-container {
    flex: 1;
    display: flex;
    flex-direction: column;
    position: relative;
    z-index: 1;
}

/* ============================================
   TYPOGRAPHY
   ============================================ */
h1 {
    font-family: var(--font-heading);
    font-size: clamp(2.5rem, 8vw, 5rem);
    font-weight: 800;
    margin-bottom: 1rem;
    color: var(--accent-color);
    text-shadow: var(--accent-glow);
    line-height: 1.1;
    letter-spacing: -1px;
}

h2 {
    font-family: var(--font-heading);
    font-size: clamp(1.8rem, 5vw, 2.8rem);
    font-weight: 700;
    margin-bottom: 0.8rem;
    color: var(--text-color);
    letter-spacing: -0.5px;
}

h3 {
    font-family: var(--font-heading);
    font-size: clamp(1.3rem, 3vw, 1.8rem);
    font-weight: 600;
    margin-bottom: 0.6rem;
    color: var(--text-color);
}

p {
    color: var(--text-secondary);
    line-height: 1.8;
}

/* ============================================
   UI COMPONENTS
   ============================================ */

/* Glass Panel */
.glass-panel {
    background: var(--panel-bg);
    backdrop-filter: blur(var(--blur-amt));
    -webkit-backdrop-filter: blur(var(--blur-amt));
    border: 1px solid var(--border-color);
    border-radius: var(--border-radius);
    box-shadow: 
        0 20px 60px rgba(0, 0, 0, 0.2),
        inset 0 1px 0 rgba(255, 255, 255, 0.1);
    transition: all var(--transition-base);
}

.glass-panel:hover {
    border-color: var(--accent-color);
    box-shadow: 
        0 25px 70px rgba(0, 217, 255, 0.15),
        inset 0 1px 0 rgba(255, 255, 255, 0.15);
}

/* Center View */
.center-view {
    flex: 1;
    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: center;
    text-align: center;
    padding: clamp(1.5rem, 5vw, 3rem);
    animation: fadeUpStagger 0.7s cubic-bezier(0.16, 1, 0.3, 1);
}

/* Buttons */
button {
    background-color: var(--panel-bg-light);
    color: var(--text-color);
    border: 2px solid var(--border-color);
    padding: 0.9rem 2rem;
    font-size: 1rem;
    font-weight: 600;
    border-radius: var(--btn-radius);
    cursor: pointer;
    transition: all var(--transition-fast);
    font-family: var(--font-main);
    min-height: 48px;
    display: inline-flex;
    align-items: center;
    justify-content: center;
    gap: 0.5rem;
    position: relative;
    overflow: hidden;
}

button::before {
    content: '';
    position: absolute;
    top: 0;
    left: -100%;
    width: 100%;
    height: 100%;
    background: linear-gradient(90deg, transparent, rgba(255, 255, 255, 0.1), transparent);
    transition: left var(--transition-fast);
}

button:hover::before {
    left: 100%;
}

button:hover:not(:disabled) {
    border-color: var(--accent-color);
    box-shadow: 
        var(--accent-glow),
        0 10px 30px rgba(0, 217, 255, 0.1);
    transform: translateY(-2px);
}

button:active:not(:disabled) {
    transform: translateY(0);
}

button:disabled {
    opacity: 0.5;
    cursor: not-allowed;
}

/* Primary Button */
.btn-primary {
    background: linear-gradient(135deg, var(--accent-color), var(--accent-light));
    color: var(--bg-color);
    border-color: transparent;
    font-weight: 700;
    box-shadow: var(--accent-glow);
}

.btn-primary:hover:not(:disabled) {
    background: linear-gradient(135deg, var(--accent-light), var(--accent-color));
    box-shadow: var(--accent-glow-strong);
    transform: translateY(-3px);
}

/* Secondary Button */
.btn-secondary {
    background: var(--panel-bg-light);
    color: var(--text-color);
    border-color: var(--border-color);
}

.btn-secondary:hover:not(:disabled) {
    background: var(--panel-bg);
    border-color: var(--accent-color);
}

/* Kids Theme Button */
.theme-kids .btn-primary {
    color: white;
    border-color: transparent;
    box-shadow: 0 8px 0px rgba(236, 72, 153, 0.3);
}

.theme-kids .btn-primary:hover:not(:disabled) {
    background: linear-gradient(135deg, var(--accent-light), var(--accent-color));
    transform: translateY(3px);
    box-shadow: 0 5px 0px rgba(236, 72, 153, 0.4);
}

/* Input Fields */
input[type="text"],
select {
    background: var(--panel-bg-light);
    color: var(--text-color);
    border: 2px solid var(--border-color);
    padding: 1rem 1.5rem;
    font-size: 1rem;
    border-radius: var(--btn-radius);
    outline: none;
    margin-bottom: 1.5rem;
    width: 100%;
    max-width: 500px;
    text-align: center;
    font-family: var(--font-main);
    font-weight: 500;
    transition: all var(--transition-base);
}

input[type="text"]:focus,
select:focus {
    border-color: var(--accent-color);
    box-shadow: 
        var(--accent-glow),
        inset 0 0 0 1px var(--border-color);
    background: var(--panel-bg);
}

.theme-light input[type="text"],
.theme-light select {
    background: #fff;
}

/* ============================================
   LAYOUT COMPONENTS
   ============================================ */

/* Game Layout */
.game-layout {
    display: flex;
    height: 100vh;
    overflow: hidden;
    gap: 1px;
    background: var(--border-color);
}

/* Panels */
.panel-left {
    flex: 1.2;
    padding: 2rem;
    overflow-y: auto;
    background: linear-gradient(135deg, var(--bg-color) 0%, var(--bg-secondary) 100%);
    display: flex;
    flex-direction: column;
    gap: 1.5rem;
}

.panel-right {
    flex: 1;
    display: flex;
    align-items: center;
    justify-content: center;
    position: relative;
    background: var(--panel-bg);
    overflow: hidden;
}

/* HUD (Heads-Up Display) */
.hud {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 1.2rem 1.5rem;
    background: var(--panel-bg-light);
    border: 1px solid var(--border-color);
    font-family: var(--font-mono);
    font-weight: 600;
    border-radius: var(--btn-radius);
    font-size: 0.95rem;
    gap: 1rem;
    flex-wrap: wrap;
}

.hud-item {
    display: flex;
    align-items: center;
    gap: 0.5rem;
}

.hud-value {
    color: var(--accent-color);
    font-weight: 700;
}

.hud-label {
    color: var(--text-tertiary);
    font-size: 0.85rem;
}

/* Question Box */
.question-box {
    font-size: clamp(1.4rem, 4vw, 2rem);
    line-height: 1.8;
    margin-bottom: 2.5rem;
    font-weight: 700;
    color: var(--text-color);
    letter-spacing: -0.3px;
}

/* Options Grid */
.options-grid {
    display: flex;
    flex-direction: column;
    gap: 1rem;
    margin-bottom: 2rem;
}

.option-btn {
    text-align: left;
    padding: 1.3rem 1.8rem;
    display: flex;
    align-items: center;
    gap: 1.2rem;
    font-size: 1.1rem;
    line-height: 1.5;
    transition: all var(--transition-fast);
    border-radius: var(--btn-radius);
    background: var(--panel-bg-light);
    border: 2px solid var(--border-color);
    color: var(--text-color);
    cursor: pointer;
    font-weight: 500;
    position: relative;
}

.option-btn::before {
    content: '';
    position: absolute;
    left: 0;
    top: 0;
    bottom: 0;
    width: 4px;
    background: transparent;
    border-radius: var(--btn-radius) 0 0 var(--btn-radius);
    transition: all var(--transition-fast);
}

body[dir="rtl"] .option-btn::before {
    left: auto;
    right: 0;
    border-radius: 0 var(--btn-radius) var(--btn-radius) 0;
}

.option-btn:hover {
    border-color: var(--accent-color);
    transform: translateX(8px);
    box-shadow: 0 8px 20px rgba(0, 217, 255, 0.1);
}

body[dir="rtl"] .option-btn:hover {
    transform: translateX(-8px);
}

.option-btn.selected {
    border-color: var(--accent-color);
    background: linear-gradient(135deg, rgba(0, 217, 255, 0.1), rgba(0, 217, 255, 0.05));
    box-shadow: 
        0 0 0 1px var(--accent-color),
        var(--accent-glow);
}

.option-btn.selected::before {
    width: 6px;
    background: linear-gradient(180deg, var(--accent-color), var(--accent-light));
    box-shadow: var(--accent-glow);
}

/* Feedback Box */
.feedback-box {
    padding: 1.5rem;
    border-radius: var(--btn-radius);
    margin-bottom: 1rem;
    font-weight: 600;
    font-size: 1rem;
    animation: slideInUp 0.4s cubic-bezier(0.16, 1, 0.3, 1);
    line-height: 1.8;
    border-left: 4px solid;
    background: var(--panel-bg-light);
}

.feedback-success {
    background: linear-gradient(135deg, rgba(16, 185, 129, 0.1), rgba(16, 185, 129, 0.05));
    border-left-color: var(--success-color);
    color: var(--success-light);
}

.feedback-error {
    background: linear-gradient(135deg, rgba(239, 68, 68, 0.1), rgba(239, 68, 68, 0.05));
    border-left-color: var(--error-color);
    color: var(--error-light);
}

/* Progress Bar */
.progress-bar {
    height: 8px;
    background: var(--panel-bg-light);
    border-radius: 10px;
    overflow: hidden;
    margin-bottom: 1.5rem;
    border: 1px solid var(--border-color);
}

.progress-fill {
    height: 100%;
    background: linear-gradient(90deg, var(--accent-color), var(--accent-light));
    border-radius: 10px;
    transition: width var(--transition-slow);
    box-shadow: var(--accent-glow);
}

/* Loader */
.loader {
    border: 4px solid var(--border-color);
    border-top: 4px solid var(--accent-color);
    border-radius: 50%;
    width: 60px;
    height: 60px;
    animation: spin 1s linear infinite;
    margin: 2rem auto;
    box-shadow: var(--accent-glow);
}

/* ============================================
   ANIMATIONS
   ============================================ */

@keyframes fadeUp {
    from {
        opacity: 0;
        transform: translateY(30px);
    }
    to {
        opacity: 1;
        transform: translateY(0);
    }
}

@keyframes fadeUpStagger {
    0% {
        opacity: 0;
        transform: translateY(40px);
    }
    100% {
        opacity: 1;
        transform: translateY(0);
    }
}

@keyframes slideInUp {
    from {
        opacity: 0;
        transform: translateY(20px);
    }
    to {
        opacity: 1;
        transform: translateY(0);
    }
}

@keyframes float {
    0%, 100% {
        transform: translateY(0px);
    }
    50% {
        transform: translateY(-20px);
    }
}

@keyframes spin {
    0% {
        transform: rotate(0deg);
    }
    100% {
        transform: rotate(360deg);
    }
}

@keyframes happyBounce {
    0% {
        transform: scale(1);
    }
    50% {
        transform: scale(1.15) translateY(-25px);
    }
    100% {
        transform: scale(1) translateY(0);
    }
}

@keyframes sadShake {
    0%, 100% {
        transform: translateX(0) rotate(0deg);
    }
    25% {
        transform: translateX(-15px) rotate(-3deg);
    }
    75% {
        transform: translateX(15px) rotate(3deg);
    }
}

.anim-float {
    animation: float 4s ease-in-out infinite;
}

.anim-bounce {
    animation: happyBounce 0.6s cubic-bezier(0.175, 0.885, 0.32, 1.275);
}

.anim-shake {
    animation: sadShake 0.5s ease-in-out;
}

/* ============================================
   RESPONSIVE DESIGN
   ============================================ */

/* Mobile Stacking */
@media (max-width: 899px) {
    .game-layout {
        flex-direction: column;
        gap: 0;
    }

    .panel-right {
        flex: 0 0 40vh;
        border-top: 1px solid var(--border-color);
        border-bottom: none;
        background: radial-gradient(circle at center, rgba(0, 217, 255, 0.05) 0%, transparent 70%);
    }

    .panel-left {
        flex: 1;
        padding: 1.5rem;
        overflow-y: auto;
    }

    .hud {
        font-size: 0.85rem;
        padding: 1rem;
        gap: 0.8rem;
    }

    .question-box {
        margin-bottom: 1.5rem;
    }

    .option-btn {
        padding: 1rem 1.2rem;
        font-size: 1rem;
    }

    h1 {
        font-size: clamp(2rem, 6vw, 3rem);
    }
}

/* Tablet */
@media (min-width: 900px) and (max-width: 1200px) {
    .panel-left {
        flex: 1.1;
        padding: 2.5rem;
    }

    .option-btn {
        padding: 1.2rem 1.5rem;
    }
}

/* Scrollbar Styling */
::-webkit-scrollbar {
    width: 8px;
}

::-webkit-scrollbar-track {
    background: var(--panel-bg-light);
}

::-webkit-scrollbar-thumb {
    background: var(--border-color);
    border-radius: 10px;
    transition: all var(--transition-base);
}

::-webkit-scrollbar-thumb:hover {
    background: var(--accent-color);
    box-shadow: var(--accent-glow);
}

/* ============================================
   UTILITY CLASSES
   ============================================ */

.text-accent {
    color: var(--accent-color);
}

.text-success {
    color: var(--success-color);
}

.text-error {
    color: var(--error-color);
}

.mb-1 { margin-bottom: 1rem; }
.mb-2 { margin-bottom: 2rem; }
.mb-3 { margin-bottom: 3rem; }

.mt-1 { margin-top: 1rem; }
.mt-2 { margin-top: 2rem; }

.gap-1 { gap: 1rem; }
.gap-2 { gap: 2rem; }

.grid-2 {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(140px, 1fr));
    gap: 1rem;
}

.grid-3 {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(120px, 1fr));
    gap: 1rem;
}

/* Focus visible for accessibility */
button:focus-visible,
input:focus-visible,
select:focus-visible {
    outline: 2px solid var(--accent-color);
    outline-offset: 2px;
}

/* Reduce motion for accessibility */
@media (prefers-reduced-motion: reduce) {
    *,
    *::before,
    *::after {
        animation-duration: 0.01ms !important;
        animation-iteration-count: 1 !important;
        transition-duration: 0.01ms !important;
    }
}