/* Global resets and utility styles */
* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
    -webkit-touch-callout: none;
    -webkit-user-select: none;
    -khtml-user-select: none;
    -moz-user-select: none;
    -ms-user-select: none;
    user-select: none;
    -webkit-tap-highlight-color: transparent;
}

/* Design system tokens */
:root {
    /* Colors */
    --color-primary: #ff9800;
    --color-primary-hover: #ffa726;
    --color-primary-light: rgba(255, 152, 0, 0.1);
    --color-secondary: #333;
    --color-secondary-hover: #444;
    --color-background: #1a1a1a;
    --color-surface: #222;
    --color-surface-hover: #2a2a2a;
    --color-text: #fff;
    --color-text-secondary: #ccc;
    --color-text-muted: #999;
    --color-border: #333;
    --color-success: #4caf50;
    --color-danger: #f44336;
    --color-warning: #ff9800;
    
    /* Spacing system - 8px base */
    --space-xs: 0.25rem;  /* 4px */
    --space-sm: 0.5rem;   /* 8px */
    --space-md: 1rem;     /* 16px */
    --space-lg: 1.5rem;   /* 24px */
    --space-xl: 2rem;     /* 32px */
    --space-xxl: 3rem;    /* 48px */
    
    /* Typography */
    --font-size-xs: 0.75rem;   /* 12px */
    --font-size-sm: 0.875rem;  /* 14px */
    --font-size-base: 1rem;    /* 16px */
    --font-size-lg: 1.125rem;  /* 18px */
    --font-size-xl: 1.25rem;   /* 20px */
    --font-size-xxl: 1.5rem;   /* 24px */
    --font-size-xxxl: 2rem;    /* 32px */
    
    /* Touch targets */
    --touch-target-min: 44px;
    --touch-target-comfortable: 48px;
    
    /* Border radius */
    --radius-sm: 4px;
    --radius-md: 8px;
    --radius-lg: 12px;
    --radius-xl: 16px;
    
    /* Shadows */
    --shadow-sm: 0 1px 3px rgba(0, 0, 0, 0.12);
    --shadow-md: 0 4px 6px rgba(0, 0, 0, 0.16);
    --shadow-lg: 0 8px 24px rgba(0, 0, 0, 0.24);
    
    /* Transitions */
    --transition-fast: 0.15s ease;
    --transition-base: 0.2s ease;
    --transition-slow: 0.3s ease;
}

/* Tablet-specific design tokens */
@media (min-width: 768px) and (max-width: 1024px) {
    :root {
        --touch-target-min: 48px;
        --touch-target-comfortable: 56px;
        --space-md: 1.25rem;  /* 20px */
        --space-lg: 2rem;     /* 32px */
        --space-xl: 2.5rem;   /* 40px */
        --font-size-base: 1.125rem;  /* 18px */
        --font-size-lg: 1.25rem;     /* 20px */
        --font-size-xl: 1.5rem;      /* 24px */
        --font-size-xxl: 1.75rem;    /* 28px */
        --font-size-xxxl: 2.25rem;   /* 36px */
    }
}

body {
    font-family: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, sans-serif;
    background-color: var(--color-background);
    color: var(--color-text);
    min-height: 100vh;
    overscroll-behavior: none;
    line-height: 1.5;
    -webkit-font-smoothing: antialiased;
    -moz-osx-font-smoothing: grayscale;
}

/* Improved input styling for better tablet experience */
input, select {
    min-height: var(--touch-target-comfortable);
    padding: var(--space-md);
    font-size: var(--font-size-base);
    border: 2px solid var(--color-border);
    border-radius: var(--radius-md);
    background: var(--color-surface);
    color: var(--color-text);
    transition: border-color var(--transition-base);
}

input:focus, select:focus {
    outline: none;
    border-color: var(--color-primary);
    box-shadow: 0 0 0 3px var(--color-primary-light);
}

/* Enhanced button styling */
.btn {
    min-height: var(--touch-target-comfortable);
    padding: var(--space-md) var(--space-lg);
    color: var(--color-text);
    background: var(--color-secondary);
    border: none;
    border-radius: var(--radius-md);
    font-size: var(--font-size-base);
    font-weight: 600;
    cursor: pointer;
    touch-action: manipulation;
    transition: all var(--transition-base);
    display: inline-flex;
    align-items: center;
    justify-content: center;
    gap: var(--space-sm);
    text-decoration: none;
    user-select: none;
}

.btn:hover {
    background: var(--color-secondary-hover);
    transform: translateY(-1px);
}

.btn:active {
    transform: translateY(0);
}

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

.btn--secondary {
    background: #333;
    color: #fff;
    border: 2px solid #555;
}

.btn--secondary:hover {
    background: #444;
    border-color: #666;
    transform: translateY(-1px);
    box-shadow: 0 4px 12px rgba(0, 0, 0, 0.3);
}

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

/* Utility button for new game with better spacing */
.new-game-button {
    width: 100%;
    background: var(--color-primary);
    color: white;
    border: none;
    border-radius: var(--radius-lg);
    font-size: var(--font-size-xxl);
    font-weight: 700;
    padding: var(--space-xl) var(--space-lg);
    margin-bottom: var(--space-lg);
    cursor: pointer;
    transition: all var(--transition-base);
    text-align: center;
    display: flex;
    align-items: center;
    justify-content: center;
    box-shadow: var(--shadow-lg);
    letter-spacing: 0.5px;
    gap: var(--space-md);
    min-height: var(--touch-target-comfortable);
}

.new-game-button::before {
    content: '+';
    font-size: 2.2rem;
    font-weight: 900;
    display: inline-block;
    line-height: 1;
}

.new-game-button:hover {
    background: var(--color-primary-hover);
    transform: translateY(-2px);
    box-shadow: 0 8px 40px rgba(255, 152, 0, 0.4);
}

.new-game-button:active {
    transform: translateY(-1px);
}

/* Navigation buttons with improved spacing */
.nav-buttons {
    display: flex;
    flex-direction: column;
    gap: var(--space-md);
    margin: var(--space-lg) 0 0 0;
}

/* Tablet-specific improvements */
@media (min-width: 768px) and (max-width: 1024px) {
    .nav-buttons {
        flex-direction: row;
        gap: var(--space-lg);
    }
    
    .btn {
        flex: 1;
        min-height: var(--touch-target-comfortable);
    }
    
    .new-game-button {
        padding: var(--space-xxl) var(--space-xl);
        font-size: var(--font-size-xxxl);
    }
}

/* Enhanced modal styling */
.modal {
    position: fixed;
    top: 0;
    left: 0;
    width: 100vw;
    height: 100vh;
    background-color: rgba(0, 0, 0, 0.8);
    backdrop-filter: blur(4px);
    z-index: 9999;
    display: flex;
    justify-content: center;
    align-items: center;
    padding: var(--space-lg);
}

.modal.show {
    display: flex;
}

/* Screen reader only content */
.sr-only {
    position: absolute;
    width: 1px;
    height: 1px;
    padding: 0;
    margin: -1px;
    overflow: hidden;
    clip: rect(0, 0, 0, 0);
    white-space: nowrap;
    border: 0;
}


/* Skip link for keyboard navigation */
.skip-link {
    position: absolute;
    top: -40px;
    left: 6px;
    background: var(--color-primary);
    color: white;
    padding: 8px;
    text-decoration: none;
    border-radius: 4px;
    z-index: 10000;
}

.skip-link:focus {
    top: 6px;
}

/* Responsive fullscreen toggle */
@media screen and (max-width: 480px) {
    .fullscreenToggle {
        bottom: var(--space-md);
        right: var(--space-md);
        width: 40px;
        height: 40px;
    }
}

@media (min-width: 768px) and (max-width: 1024px) {
    .fullscreenToggle {
        bottom: var(--space-lg);
        right: var(--space-lg);
        width: 56px;
        height: 56px;
    }
}