/**
 * Brick Wall Demo Styles
 * Modern, mobile-first design
 */

/* ===== RESET & BASE ===== */
* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

:root {
    /* Colors */
    --color-primary: #4F46E5;
    --color-primary-dark: #4338CA;
    --color-secondary: #10B981;
    --color-danger: #EF4444;
    --color-warning: #F59E0B;
    --color-bg: #F9FAFB;
    --color-surface: #FFFFFF;
    --color-text: #111827;
    --color-text-light: #6B7280;
    --color-border: #E5E7EB;

    /* Brick Colors */
    --color-brick: #FFFFFF;
    --color-brick-border: #D1D5DB;
    --color-brick-quiz: #FEF3C7;
    --color-brick-illuminated: #FBBF24;

    /* Spacing */
    --spacing-xs: 0.25rem;
    --spacing-sm: 0.5rem;
    --spacing-md: 1rem;
    --spacing-lg: 1.5rem;
    --spacing-xl: 2rem;

    /* Font */
    --font-sans: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', sans-serif;
    --font-chinese: 'Noto Sans SC', sans-serif;

    /* Shadows */
    --shadow-sm: 0 1px 2px 0 rgba(0, 0, 0, 0.05);
    --shadow-md: 0 4px 6px -1px rgba(0, 0, 0, 0.1);
    --shadow-lg: 0 10px 15px -3px rgba(0, 0, 0, 0.1);
    --shadow-xl: 0 20px 25px -5px rgba(0, 0, 0, 0.1);

    /* Transitions */
    --transition-fast: 150ms ease-in-out;
    --transition-medium: 300ms ease-in-out;
}

body {
    font-family: var(--font-sans);
    background: var(--color-bg);
    color: var(--color-text);
    line-height: 1.6;
    overflow-x: hidden;
    -webkit-font-smoothing: antialiased;
    -moz-osx-font-smoothing: grayscale;
}

/* ===== LOADING SCREEN ===== */
.loading-screen {
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    background: var(--color-primary);
    display: flex;
    align-items: center;
    justify-content: center;
    z-index: 9999;
}

.loading-content {
    text-align: center;
    color: white;
}

.loading-spinner {
    width: 50px;
    height: 50px;
    border: 4px solid rgba(255, 255, 255, 0.3);
    border-top-color: white;
    border-radius: 50%;
    animation: spin 1s linear infinite;
    margin: 0 auto var(--spacing-md);
}

@keyframes spin {
    to { transform: rotate(360deg); }
}

#loading-text {
    font-size: 1.125rem;
    font-weight: 500;
}

/* ===== GAME CONTAINER ===== */
.game-container {
    max-width: 600px;
    margin: 0 auto;
    min-height: 100vh;
    display: flex;
    flex-direction: column;
    background: var(--color-surface);
    box-shadow: var(--shadow-lg);
}

/* ===== HEADER ===== */
.game-header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: var(--spacing-md);
    background: var(--color-primary);
    color: white;
    box-shadow: var(--shadow-md);
}

.header-left {
    display: flex;
    align-items: center;
    gap: var(--spacing-sm);
}

.header-left h1 {
    font-size: 1.5rem;
    font-weight: 700;
}

.demo-badge {
    background: rgba(255, 255, 255, 0.2);
    padding: var(--spacing-xs) var(--spacing-sm);
    border-radius: 4px;
    font-size: 0.75rem;
    font-weight: 600;
}

.header-right {
    display: flex;
    gap: var(--spacing-lg);
}

.stat {
    display: flex;
    flex-direction: column;
    align-items: flex-end;
}

.stat-label {
    font-size: 0.75rem;
    opacity: 0.9;
    text-transform: uppercase;
    letter-spacing: 0.5px;
}

.stat-value {
    font-size: 1.5rem;
    font-weight: 700;
}

/* ===== INSTRUCTIONS ===== */
.instructions {
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    color: white;
    padding: var(--spacing-md);
    text-align: center;
    font-size: 0.875rem;
    font-weight: 500;
}

/* ===== BRICK WALL ===== */
.brick-wall-container {
    flex: 1;
    position: relative;
    padding: var(--spacing-md);
    background: var(--color-bg);
    overflow-y: auto;
    min-height: 300px;
    max-height: 400px;
}

.brick-wall {
    display: flex;
    flex-wrap: wrap;
    gap: var(--spacing-sm);
    align-content: flex-start;
}

.brick {
    flex: 0 0 calc(33.333% - var(--spacing-sm));
    background: var(--color-brick);
    border: 2px solid var(--color-brick-border);
    border-radius: 8px;
    padding: var(--spacing-md);
    text-align: center;
    cursor: default;
    transition: all var(--transition-medium);
    box-shadow: var(--shadow-sm);
}

.brick:hover {
    transform: translateY(-2px);
    box-shadow: var(--shadow-md);
}

.brick-word {
    font-family: var(--font-chinese);
    font-size: 1.75rem;
    font-weight: 700;
    color: var(--color-text);
    margin-bottom: var(--spacing-xs);
}

.brick-pinyin {
    font-size: 0.75rem;
    color: var(--color-text-light);
    font-weight: 500;
}

/* Brick States */
.brick.has-quiz {
    background: var(--color-brick-quiz);
    border-color: var(--color-warning);
    box-shadow: 0 0 0 2px rgba(245, 158, 11, 0.2);
}

.brick.illuminated {
    background: var(--color-brick-illuminated);
    border-color: var(--color-warning);
    animation: illuminate 300ms ease-in-out;
    transform: scale(1.05);
}

@keyframes illuminate {
    0%, 100% { opacity: 1; }
    50% { opacity: 0.8; }
}

/* Wall Warning */
.wall-warning {
    position: absolute;
    top: var(--spacing-md);
    left: 50%;
    transform: translateX(-50%);
    background: var(--color-danger);
    color: white;
    padding: var(--spacing-sm) var(--spacing-md);
    border-radius: 8px;
    font-weight: 600;
    box-shadow: var(--shadow-lg);
    animation: pulse 1s ease-in-out infinite;
}

.wall-warning.hidden {
    display: none;
}

@keyframes pulse {
    0%, 100% { transform: translateX(-50%) scale(1); }
    50% { transform: translateX(-50%) scale(1.05); }
}

/* ===== TIMER ===== */
.timer-container {
    padding: var(--spacing-md);
    background: var(--color-surface);
    border-top: 1px solid var(--color-border);
}

.timer-label {
    font-size: 0.875rem;
    color: var(--color-text-light);
    margin-bottom: var(--spacing-xs);
    text-align: center;
}

.timer-bar {
    height: 8px;
    background: var(--color-border);
    border-radius: 4px;
    overflow: hidden;
}

.timer-progress {
    height: 100%;
    background: linear-gradient(90deg, var(--color-primary), var(--color-secondary));
    transition: width 100ms linear;
}

/* ===== QUIZ AREA ===== */
.quiz-area {
    padding: var(--spacing-lg) var(--spacing-md);
    background: var(--color-surface);
    border-top: 2px solid var(--color-border);
    box-shadow: 0 -4px 6px -1px rgba(0, 0, 0, 0.05);
}

.quiz-area-label {
    text-align: center;
    font-size: 0.875rem;
    font-weight: 600;
    color: var(--color-text-light);
    margin-bottom: var(--spacing-md);
    text-transform: uppercase;
    letter-spacing: 0.5px;
}

.bottom-characters {
    display: flex;
    gap: var(--spacing-md);
    justify-content: center;
}

.bottom-char {
    flex: 1;
    max-width: 80px;
    aspect-ratio: 1;
    font-family: var(--font-chinese);
    font-size: 2rem;
    font-weight: 700;
    background: var(--color-primary);
    color: white;
    border: none;
    border-radius: 12px;
    cursor: pointer;
    transition: all var(--transition-fast);
    box-shadow: var(--shadow-md);
}

.bottom-char:hover {
    transform: translateY(-4px);
    box-shadow: var(--shadow-lg);
    background: var(--color-primary-dark);
}

.bottom-char:active {
    transform: translateY(-2px);
}

/* ===== FOOTER CTA ===== */
.footer-cta {
    padding: var(--spacing-lg);
    background: var(--color-bg);
    border-top: 1px solid var(--color-border);
    text-align: center;
}

.footer-cta p {
    margin-bottom: var(--spacing-md);
    color: var(--color-text-light);
    font-weight: 500;
}

.btn-download {
    display: inline-block;
    padding: var(--spacing-md) var(--spacing-xl);
    background: var(--color-secondary);
    color: white;
    text-decoration: none;
    border-radius: 8px;
    font-weight: 600;
    transition: all var(--transition-fast);
    box-shadow: var(--shadow-md);
}

.btn-download:hover {
    background: #059669;
    transform: translateY(-2px);
    box-shadow: var(--shadow-lg);
}

/* ===== MODAL ===== */
.modal {
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    background: rgba(0, 0, 0, 0.5);
    display: flex;
    align-items: center;
    justify-content: center;
    z-index: 1000;
    padding: var(--spacing-md);
}

.modal.hidden {
    display: none;
}

.modal-content {
    background: var(--color-surface);
    border-radius: 16px;
    box-shadow: var(--shadow-xl);
    max-width: 500px;
    width: 100%;
    max-height: 90vh;
    overflow-y: auto;
    animation: modalSlideIn 300ms ease-out;
}

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

/* ===== QUIZ MODAL ===== */
.quiz-modal {
    padding: var(--spacing-xl);
}

.quiz-header h2 {
    text-align: center;
    color: var(--color-primary);
    margin-bottom: var(--spacing-lg);
}

.quiz-question {
    font-size: 1.25rem;
    font-weight: 600;
    text-align: center;
    margin-bottom: var(--spacing-lg);
    color: var(--color-text);
}

.quiz-options {
    display: flex;
    flex-direction: column;
    gap: var(--spacing-md);
}

.quiz-option {
    padding: var(--spacing-md);
    background: var(--color-bg);
    border: 2px solid var(--color-border);
    border-radius: 8px;
    font-size: 1rem;
    font-weight: 500;
    cursor: pointer;
    transition: all var(--transition-fast);
}

.quiz-option:hover:not(:disabled) {
    background: var(--color-primary);
    color: white;
    border-color: var(--color-primary);
    transform: translateX(4px);
}

.quiz-option:disabled {
    opacity: 0.6;
    cursor: not-allowed;
}

.quiz-feedback {
    margin-top: var(--spacing-lg);
    padding: var(--spacing-md);
    border-radius: 8px;
    text-align: center;
    font-weight: 600;
    font-size: 1.125rem;
}

.quiz-feedback.correct {
    background: #D1FAE5;
    color: #065F46;
}

.quiz-feedback.incorrect {
    background: #FEE2E2;
    color: #991B1B;
}

/* ===== GAME OVER MODAL ===== */
.game-over-modal {
    padding: var(--spacing-xl);
}

.game-over-header {
    text-align: center;
    margin-bottom: var(--spacing-xl);
}

.game-over-header h2 {
    font-size: 2rem;
    color: var(--color-primary);
}

.stats-grid {
    display: grid;
    grid-template-columns: repeat(2, 1fr);
    gap: var(--spacing-md);
    margin-bottom: var(--spacing-xl);
}

.stat-card {
    background: var(--color-bg);
    padding: var(--spacing-lg);
    border-radius: 12px;
    text-align: center;
    border: 2px solid var(--color-border);
}

.stat-card .stat-label {
    font-size: 0.875rem;
    color: var(--color-text-light);
    margin-bottom: var(--spacing-sm);
    text-transform: uppercase;
    letter-spacing: 0.5px;
}

.stat-large {
    font-size: 2rem;
    font-weight: 700;
    color: var(--color-primary);
}

.game-over-actions {
    display: flex;
    gap: var(--spacing-md);
    margin-bottom: var(--spacing-lg);
}

.btn {
    flex: 1;
    padding: var(--spacing-md);
    border: none;
    border-radius: 8px;
    font-size: 1rem;
    font-weight: 600;
    cursor: pointer;
    transition: all var(--transition-fast);
    box-shadow: var(--shadow-sm);
}

.btn-primary {
    background: var(--color-primary);
    color: white;
}

.btn-primary:hover {
    background: var(--color-primary-dark);
    transform: translateY(-2px);
    box-shadow: var(--shadow-md);
}

.btn-secondary {
    background: var(--color-secondary);
    color: white;
}

.btn-secondary:hover {
    background: #059669;
    transform: translateY(-2px);
    box-shadow: var(--shadow-md);
}

.game-over-note {
    font-size: 0.875rem;
    color: var(--color-text-light);
    text-align: center;
    line-height: 1.6;
}

/* ===== RESPONSIVE ===== */
@media (max-width: 480px) {
    .game-header {
        flex-direction: column;
        gap: var(--spacing-md);
        align-items: flex-start;
    }

    .header-right {
        width: 100%;
        justify-content: space-around;
    }

    .brick {
        flex: 0 0 calc(50% - var(--spacing-sm));
    }

    .bottom-char {
        font-size: 1.5rem;
        max-width: 60px;
    }

    .stats-grid {
        grid-template-columns: 1fr;
    }

    .game-over-actions {
        flex-direction: column;
    }
}

/* ===== ACCESSIBILITY ===== */
@media (prefers-reduced-motion: reduce) {
    * {
        animation-duration: 0.01ms !important;
        animation-iteration-count: 1 !important;
        transition-duration: 0.01ms !important;
    }
}

/* Focus states for keyboard navigation */
button:focus-visible,
.bottom-char:focus-visible,
.quiz-option:focus-visible {
    outline: 3px solid var(--color-primary);
    outline-offset: 2px;
}