/* ============================================
   DODO SYNC DESIGN SYSTEM
   Unified UX/UI framework for all pages
   ============================================ */

/* --- CSS Variables (Design Tokens) --- */
:root {
    /* Colors - Semantic naming */
    --color-primary: #4f46e5;
    --color-primary-hover: #4338ca;
    --color-surface: #ffffff;
    --color-background: #f8fafc;
    --color-border: #e2e8f0;
    --color-text-primary: #0f172a;
    --color-text-secondary: #64748b;
    --color-text-muted: #94a3b8;
    --color-success: #10b981;
    --color-warning: #f59e0b;
    --color-danger: #ef4444;
    --color-info: #3b82f6;
    
    /* Spacing System (8px base) */
    --space-1: 0.25rem;  /* 4px */
    --space-2: 0.5rem;   /* 8px */
    --space-3: 0.75rem;  /* 12px */
    --space-4: 1rem;     /* 16px */
    --space-5: 1.25rem;  /* 20px */
    --space-6: 1.5rem;   /* 24px */
    --space-8: 2rem;     /* 32px */
    --space-10: 2.5rem;  /* 40px */
    --space-12: 3rem;    /* 48px */
    
    /* Typography */
    --font-sans: "Inter", -apple-system, BlinkMacSystemFont, "Segoe UI", system-ui, sans-serif;
    --font-mono: "JetBrains Mono", "Fira Code", "Courier New", monospace;
    
    --text-xs: 0.75rem;    /* 12px */
    --text-sm: 0.875rem;   /* 14px */
    --text-base: 1rem;     /* 16px */
    --text-lg: 1.125rem;   /* 18px */
    --text-xl: 1.25rem;    /* 20px */
    --text-2xl: 1.5rem;    /* 24px */
    --text-3xl: 1.875rem;  /* 30px */
    
    --line-height-tight: 1.25;
    --line-height-normal: 1.5;
    --line-height-relaxed: 1.75;
    
    /* Borders & Radius */
    --radius-sm: 0.375rem;  /* 6px */
    --radius-md: 0.5rem;    /* 8px */
    --radius-lg: 0.75rem;   /* 12px */
    --radius-full: 9999px;
    
    /* Shadows */
    --shadow-sm: 0 1px 2px 0 rgb(0 0 0 / 0.05);
    --shadow-md: 0 4px 6px -1px rgb(0 0 0 / 0.1);
    --shadow-lg: 0 10px 15px -3px rgb(0 0 0 / 0.1);
    
    /* Transitions */
    --transition-fast: 150ms ease-in-out;
    --transition-base: 250ms ease-in-out;
    
    /* Layout */
    --container-max: 1200px;
    --nav-height: 64px;
}

/* --- Base Reset & Typography --- */
* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

body {
    font-family: var(--font-sans);
    font-size: var(--text-base);
    line-height: var(--line-height-normal);
    color: var(--color-text-primary);
    background: var(--color-background);
    -webkit-font-smoothing: antialiased;
    -moz-osx-font-smoothing: grayscale;
    margin: 0;
    padding: 0;
}

/* --- Unified Navigation Component --- */
.app-nav {
    position: sticky;
    top: 0;
    z-index: 100;
    background: var(--color-surface);
    border-bottom: 1px solid var(--color-border);
    box-shadow: var(--shadow-sm);
}

.app-nav__container {
    max-width: var(--container-max);
    margin: 0 auto;
    padding: var(--space-4) var(--space-6);
    display: flex;
    justify-content: space-between;
    align-items: center;
    gap: var(--space-6);
    min-height: 64px;
}

.app-nav__brand {
    display: flex;
    flex-direction: column;
    gap: var(--space-1);
    min-width: 200px;
    flex-shrink: 0;
}

.app-nav__title {
    font-size: var(--text-xl);
    font-weight: 700;
    color: var(--color-text-primary);
    letter-spacing: -0.025em;
    margin: 0;
    text-align: left;
}

.app-nav__subtitle {
    font-size: var(--text-sm);
    color: var(--color-text-secondary);
    font-weight: 500;
    margin: 0;
    text-align: left;
    white-space: nowrap;
    overflow: hidden;
    text-overflow: ellipsis;
}

.app-nav__links {
    display: flex;
    gap: var(--space-2);
    align-items: center;
    flex-wrap: wrap;
}

.app-nav__link {
    padding: var(--space-2) var(--space-4);
    border-radius: var(--radius-full);
    text-decoration: none;
    font-size: var(--text-sm);
    font-weight: 600;
    color: var(--color-text-primary);
    background: var(--color-background);
    border: 1px solid var(--color-border);
    transition: all var(--transition-fast);
}

.app-nav__link:hover {
    background: var(--color-primary);
    color: white;
    border-color: var(--color-primary);
    transform: translateY(-1px);
}

.app-nav__link:focus-visible {
    outline: 2px solid var(--color-primary);
    outline-offset: 2px;
}

/* --- Button Component --- */
.btn {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    gap: var(--space-2);
    padding: var(--space-2) var(--space-4);
    border-radius: var(--radius-md);
    font-size: var(--text-sm);
    font-weight: 600;
    font-family: inherit;
    cursor: pointer;
    border: 1px solid transparent;
    transition: all var(--transition-fast);
    white-space: nowrap;
}

.btn:focus-visible {
    outline: 2px solid var(--color-primary);
    outline-offset: 2px;
}

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

.btn--primary:hover {
    background: var(--color-primary-hover);
    transform: translateY(-1px);
    box-shadow: var(--shadow-md);
}

.btn--secondary {
    background: var(--color-surface);
    color: var(--color-text-primary);
    border-color: var(--color-border);
}

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

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

.btn--danger:hover {
    background: #dc2626;
}

.btn--logout {
    background: var(--color-surface);
    color: var(--color-primary);
    border: 1px solid var(--color-primary);
}

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

/* --- Container & Layout --- */
.app-container {
    max-width: var(--container-max);
    margin: 0 auto;
    padding: var(--space-6) var(--space-6) var(--space-6);
}

.app-section {
    margin-bottom: var(--space-8);
}

.app-section__title {
    font-size: var(--text-2xl);
    font-weight: 700;
    margin-bottom: var(--space-4);
    color: var(--color-text-primary);
}

/* --- Card Component --- */
.card {
    background: var(--color-surface);
    border: 1px solid var(--color-border);
    border-radius: var(--radius-lg);
    padding: var(--space-6);
    box-shadow: var(--shadow-sm);
    transition: box-shadow var(--transition-base);
}

.card:hover {
    box-shadow: var(--shadow-md);
}

.card__title {
    font-size: var(--text-lg);
    font-weight: 600;
    margin-bottom: var(--space-3);
    color: var(--color-text-primary);
}

.card__content {
    font-size: var(--text-sm);
    color: var(--color-text-secondary);
    line-height: var(--line-height-relaxed);
}

/* --- Grid System --- */
.grid {
    display: grid;
    gap: var(--space-6);
}

.grid--2 {
    grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
}

.grid--3 {
    grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
}

/* --- Utility Classes --- */
.text-center { text-align: center; }
.text-muted { color: var(--color-text-muted); }
.text-sm { font-size: var(--text-sm); }
.text-xs { font-size: var(--text-xs); }
.font-mono { font-family: var(--font-mono); }
.mt-4 { margin-top: var(--space-4); }
.mb-4 { margin-bottom: var(--space-4); }
.mb-6 { margin-bottom: var(--space-6); }

/* --- Responsive Design (Mobile First) --- */
@media (max-width: 768px) {
    .app-nav__container {
        flex-direction: column;
        align-items: flex-start;
        gap: var(--space-4);
    }
    
    .app-nav__links {
        width: 100%;
        flex-direction: column;
    }
    
    .app-nav__link {
        width: 100%;
        text-align: center;
    }
    
    .app-container {
        padding: var(--space-4);
    }
}

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

/* Focus visible for keyboard navigation */
:focus-visible {
    outline: 2px solid var(--color-primary);
    outline-offset: 2px;
}