/**
 * Modern CSS Architecture
 * Component-based styling with BEM methodology
 */

/* ===== CSS Variables ===== */
:root {
    /* Colors */
    --color-primary: #3b82f6;
    --color-primary-dark: #2563eb;
    --color-secondary: #8b5cf6;
    --color-success: #10b981;
    --color-warning: #f59e0b;
    --color-danger: #ef4444;
    --color-info: #06b6d4;
    
    /* Gradients */
    --gradient-primary: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    --gradient-blue: linear-gradient(135deg, #3b82f6 0%, #2563eb 100%);
    --gradient-purple: linear-gradient(135deg, #8b5cf6 0%, #7c3aed 100%);
    --gradient-pink: linear-gradient(135deg, #ec4899 0%, #be185d 100%);
    --gradient-cyan: linear-gradient(135deg, #06b6d4 0%, #0284c7 100%);
    
    /* Spacing */
    --spacing-xs: 0.25rem;
    --spacing-sm: 0.5rem;
    --spacing-md: 1rem;
    --spacing-lg: 1.5rem;
    --spacing-xl: 2rem;
    --spacing-2xl: 3rem;
    
    /* Border Radius */
    --radius-sm: 0.5rem;
    --radius-md: 0.75rem;
    --radius-lg: 1rem;
    --radius-xl: 1.5rem;
    --radius-2xl: 2rem;
    
    /* 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 cubic-bezier(0.4, 0, 0.2, 1);
    --transition-base: 300ms cubic-bezier(0.4, 0, 0.2, 1);
    --transition-slow: 500ms cubic-bezier(0.4, 0, 0.2, 1);
}

/* ===== Base Styles ===== */
* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

body {
    font-family: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', sans-serif;
    -webkit-font-smoothing: antialiased;
    -moz-osx-font-smoothing: grayscale;
}

/* ===== Component: Navigation ===== */
.nav {
    background: rgba(255, 255, 255, 0.8);
    backdrop-filter: blur(20px);
    border-bottom: 1px solid rgba(229, 231, 235, 1);
    position: sticky;
    top: 0;
    z-index: 50;
    box-shadow: var(--shadow-sm);
}

.nav__container {
    max-width: 80rem;
    margin: 0 auto;
    padding: var(--spacing-md) var(--spacing-lg);
    display: flex;
    align-items: center;
    justify-content: space-between;
}

.nav__logo {
    display: flex;
    align-items: center;
    gap: var(--spacing-md);
}

.nav__logo-icon {
    width: 2.5rem;
    height: 2.5rem;
    background: var(--gradient-primary);
    border-radius: var(--radius-lg);
    display: flex;
    align-items: center;
    justify-content: center;
    box-shadow: var(--shadow-lg);
    animation: gradient-shift 15s ease infinite;
}

.nav__menu {
    display: flex;
    align-items: center;
    gap: var(--spacing-xs);
    list-style: none;
}

.nav__link {
    padding: var(--spacing-sm) var(--spacing-md);
    border-radius: var(--radius-lg);
    font-weight: 600;
    text-decoration: none;
    color: #374151;
    transition: all var(--transition-base);
}

.nav__link:hover {
    background: #f3f4f6;
}

.nav__link--active {
    background: var(--gradient-blue);
    color: white;
    box-shadow: var(--shadow-lg);
}

.nav__actions {
    display: flex;
    align-items: center;
    gap: var(--spacing-md);
}

/* ===== Component: Button ===== */
.btn {
    padding: var(--spacing-sm) var(--spacing-lg);
    border-radius: var(--radius-lg);
    font-weight: 700;
    border: none;
    cursor: pointer;
    transition: all var(--transition-base);
    display: inline-flex;
    align-items: center;
    justify-content: center;
    gap: var(--spacing-sm);
}

.btn--primary {
    background: var(--gradient-blue);
    color: white;
    box-shadow: var(--shadow-lg);
}

.btn--primary:hover {
    box-shadow: var(--shadow-xl);
    transform: translateY(-2px);
}

.btn--gradient {
    background: var(--gradient-primary);
    color: white;
    box-shadow: var(--shadow-lg);
    animation: gradient-shift 15s ease infinite;
    background-size: 400% 400%;
}

.btn--outline {
    background: white;
    border: 2px solid #e5e7eb;
    color: #374151;
}

.btn--outline:hover {
    border-color: var(--color-primary);
    box-shadow: var(--shadow-lg);
}

/* ===== Component: Card ===== */
.card {
    background: white;
    border-radius: var(--radius-2xl);
    box-shadow: var(--shadow-lg);
    border: 1px solid #e5e7eb;
    transition: all var(--transition-base);
}

.card--gradient {
    background: var(--gradient-blue);
    color: white;
    border: none;
}

.card--gradient-purple {
    background: var(--gradient-purple);
}

.card--gradient-pink {
    background: var(--gradient-pink);
}

.card--gradient-cyan {
    background: var(--gradient-cyan);
}

.card__header {
    padding: var(--spacing-lg);
    border-bottom: 1px solid #e5e7eb;
}

.card__body {
    padding: var(--spacing-lg);
}

.card__footer {
    padding: var(--spacing-lg);
    border-top: 1px solid #e5e7eb;
}

/* ===== Component: Stat Card ===== */
.stat-card {
    padding: var(--spacing-lg);
    border-radius: var(--radius-2xl);
    color: white;
    box-shadow: var(--shadow-xl);
    transition: all var(--transition-base);
}

.stat-card:hover {
    transform: translateY(-8px) scale(1.02);
}

.stat-card__icon {
    width: 3.5rem;
    height: 3.5rem;
    background: rgba(255, 255, 255, 0.2);
    backdrop-filter: blur(10px);
    border-radius: var(--radius-xl);
    display: flex;
    align-items: center;
    justify-content: center;
    margin-bottom: var(--spacing-md);
}

.stat-card__value {
    font-size: 3rem;
    font-weight: 900;
    line-height: 1;
    margin: var(--spacing-sm) 0;
}

.stat-card__label {
    font-size: 0.875rem;
    font-weight: 600;
    opacity: 0.9;
}

/* ===== Component: Table ===== */
.table {
    width: 100%;
    border-collapse: collapse;
}

.table__header {
    background: #f9fafb;
}

.table__header th {
    padding: var(--spacing-md) var(--spacing-xl);
    text-align: left;
    font-size: 0.75rem;
    font-weight: 700;
    color: #374151;
    text-transform: uppercase;
    letter-spacing: 0.05em;
}

.table__body tr {
    border-bottom: 1px solid #f3f4f6;
    transition: all var(--transition-fast);
}

.table__body tr:hover {
    background: linear-gradient(to right, #eff6ff, #f5f3ff);
}

.table__body td {
    padding: var(--spacing-md) var(--spacing-xl);
}

/* ===== Component: Badge ===== */
.badge {
    display: inline-flex;
    align-items: center;
    padding: var(--spacing-xs) var(--spacing-md);
    border-radius: 9999px;
    font-size: 0.75rem;
    font-weight: 700;
}

.badge--success {
    background: #d1fae5;
    color: #065f46;
}

.badge--warning {
    background: #fef3c7;
    color: #92400e;
}

.badge--info {
    background: #dbeafe;
    color: #1e40af;
}

.badge--danger {
    background: #fee2e2;
    color: #991b1b;
}

/* ===== Animations ===== */
@keyframes gradient-shift {
    0% { background-position: 0% 50%; }
    50% { background-position: 100% 50%; }
    100% { background-position: 0% 50%; }
}

@keyframes fade-in {
    from {
        opacity: 0;
        transform: translateY(10px);
    }
    to {
        opacity: 1;
        transform: translateY(0);
    }
}

.fade-in {
    animation: fade-in var(--transition-base) ease-out;
}

/* ===== Utilities ===== */
.container {
    max-width: 80rem;
    margin: 0 auto;
    padding: 0 var(--spacing-lg);
}

.grid {
    display: grid;
    gap: var(--spacing-lg);
}

.grid--2 { grid-template-columns: repeat(2, 1fr); }
.grid--3 { grid-template-columns: repeat(3, 1fr); }
.grid--4 { grid-template-columns: repeat(4, 1fr); }

.flex {
    display: flex;
}

.flex--center {
    align-items: center;
    justify-content: center;
}

.flex--between {
    align-items: center;
    justify-content: space-between;
}

.gap-sm { gap: var(--spacing-sm); }
.gap-md { gap: var(--spacing-md); }
.gap-lg { gap: var(--spacing-lg); }

.mt-sm { margin-top: var(--spacing-sm); }
.mt-md { margin-top: var(--spacing-md); }
.mt-lg { margin-top: var(--spacing-lg); }
.mt-xl { margin-top: var(--spacing-xl); }

.mb-sm { margin-bottom: var(--spacing-sm); }
.mb-md { margin-bottom: var(--spacing-md); }
.mb-lg { margin-bottom: var(--spacing-lg); }
.mb-xl { margin-bottom: var(--spacing-xl); }

/* ===== Responsive ===== */
@media (max-width: 768px) {
    .nav__menu {
        display: none;
    }
    
    .grid--2,
    .grid--3,
    .grid--4 {
        grid-template-columns: 1fr;
    }
}