/* 
 * Medical Store Inventory Management System
 * Main Stylesheet
 */

/* ============================================
   CSS Variables & Theme
   ============================================ */
:root {
    /* Primary Colors */
    --primary-color: #2563eb;
    --primary-dark: #1e40af;
    --primary-light: #3b82f6;
    
    /* Secondary Colors */
    --secondary-color: #10b981;
    --secondary-dark: #059669;
    
    /* Status Colors */
    --success-color: #10b981;
    --warning-color: #f59e0b;
    --danger-color: #ef4444;
    --info-color: #3b82f6;
    
    /* Neutral Colors */
    --text-primary: #1f2937;
    --text-secondary: #6b7280;
    --text-light: #9ca3af;
    --bg-primary: #ffffff;
    --bg-secondary: #f9fafb;
    --bg-tertiary: #f3f4f6;
    --border-color: #e5e7eb;
    
    /* 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), 0 2px 4px -1px rgba(0, 0, 0, 0.06);
    --shadow-lg: 0 10px 15px -3px rgba(0, 0, 0, 0.1), 0 4px 6px -2px rgba(0, 0, 0, 0.05);
    --shadow-xl: 0 20px 25px -5px rgba(0, 0, 0, 0.1), 0 10px 10px -5px rgba(0, 0, 0, 0.04);
    
    /* 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: 0.25rem;
    --radius-md: 0.5rem;
    --radius-lg: 0.75rem;
    --radius-xl: 1rem;
    
    /* Transitions */
    --transition-fast: 150ms ease-in-out;
    --transition-base: 250ms ease-in-out;
    --transition-slow: 350ms ease-in-out;
}

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

body {
    font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
    font-size: 16px;
    line-height: 1.6;
    color: var(--text-primary);
    background-color: var(--bg-secondary);
    min-height: 100vh;
}

a {
    text-decoration: none;
    color: var(--primary-color);
    transition: color var(--transition-fast);
}

a:hover {
    color: var(--primary-dark);
}

img {
    max-width: 100%;
    height: auto;
    display: block;
}

/* ============================================
   Layout Components
   ============================================ */
.container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 var(--spacing-md);
}

.main-wrapper {
    display: flex;
    min-height: 100vh;
}

.content-wrapper {
    flex: 1;
    padding: var(--spacing-xl);
    margin-left: 0;
    transition: margin-left var(--transition-base);
}

/* ============================================
   Header & Navigation
   ============================================ */
.header {
    background: var(--bg-primary);
    box-shadow: var(--shadow-md);
    position: sticky;
    top: 0;
    z-index: 100;
}

.navbar {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: var(--spacing-md) var(--spacing-xl);
}

.logo {
    font-size: 1.5rem;
    font-weight: 700;
    color: var(--primary-color);
    display: flex;
    align-items: center;
    gap: var(--spacing-sm);
}

.logo-icon {
    font-size: 2rem;
}

.nav-menu {
    display: flex;
    list-style: none;
    gap: var(--spacing-lg);
    align-items: center;
}

.nav-link {
    color: var(--text-primary);
    font-weight: 500;
    padding: var(--spacing-sm) var(--spacing-md);
    border-radius: var(--radius-md);
    transition: all var(--transition-fast);
    position: relative;
}

.nav-link:hover {
    background: var(--bg-tertiary);
    color: var(--primary-color);
}

.nav-link.active {
    color: var(--primary-color);
    background: var(--bg-tertiary);
}

.notification-badge {
    position: absolute;
    top: -5px;
    right: -5px;
    background: var(--danger-color);
    color: white;
    font-size: 0.7rem;
    padding: 2px 6px;
    border-radius: 10px;
    font-weight: 600;
}

.mobile-menu-toggle {
    display: none;
    background: none;
    border: none;
    font-size: 1.5rem;
    cursor: pointer;
    color: var(--text-primary);
}

/* ============================================
   Cards & Containers
   ============================================ */
.card {
    background: var(--bg-primary);
    border-radius: var(--radius-lg);
    box-shadow: var(--shadow-md);
    padding: var(--spacing-xl);
    margin-bottom: var(--spacing-lg);
    transition: transform var(--transition-fast), box-shadow var(--transition-fast);
}

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

.card-header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    margin-bottom: var(--spacing-lg);
    padding-bottom: var(--spacing-md);
    border-bottom: 2px solid var(--border-color);
}

.card-title {
    font-size: 1.5rem;
    font-weight: 700;
    color: var(--text-primary);
}

.card-body {
    padding: var(--spacing-md) 0;
}

/* ============================================
   Buttons
   ============================================ */
.btn {
    display: inline-flex;
    align-items: center;
    gap: var(--spacing-sm);
    padding: var(--spacing-sm) var(--spacing-lg);
    font-size: 0.95rem;
    font-weight: 600;
    border: none;
    border-radius: var(--radius-md);
    cursor: pointer;
    transition: all var(--transition-fast);
    text-align: center;
    text-decoration: none;
}

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

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

.btn-primary:hover:not(:disabled) {
    background: var(--primary-dark);
    transform: translateY(-1px);
    box-shadow: var(--shadow-md);
}

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

.btn-success:hover:not(:disabled) {
    background: var(--secondary-dark);
    transform: translateY(-1px);
    box-shadow: var(--shadow-md);
}

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

.btn-danger:hover:not(:disabled) {
    background: #dc2626;
    transform: translateY(-1px);
    box-shadow: var(--shadow-md);
}

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

.btn-warning:hover:not(:disabled) {
    background: #d97706;
    transform: translateY(-1px);
    box-shadow: var(--shadow-md);
}

.btn-secondary {
    background: var(--bg-tertiary);
    color: var(--text-primary);
}

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

.btn-sm {
    padding: var(--spacing-xs) var(--spacing-md);
    font-size: 0.875rem;
}

.btn-lg {
    padding: var(--spacing-md) var(--spacing-xl);
    font-size: 1.1rem;
}

/* ============================================
   Forms
   ============================================ */
.form-group {
    margin-bottom: var(--spacing-lg);
}

.form-label {
    display: block;
    margin-bottom: var(--spacing-sm);
    font-weight: 600;
    color: var(--text-primary);
}

.form-label.required::after {
    content: ' *';
    color: var(--danger-color);
}

.form-control {
    width: 100%;
    padding: var(--spacing-sm) var(--spacing-md);
    font-size: 1rem;
    border: 2px solid var(--border-color);
    border-radius: var(--radius-md);
    background: var(--bg-primary);
    color: var(--text-primary);
    transition: all var(--transition-fast);
}

.form-control:focus {
    outline: none;
    border-color: var(--primary-color);
    box-shadow: 0 0 0 3px rgba(37, 99, 235, 0.1);
}

.form-control:disabled {
    background: var(--bg-tertiary);
    cursor: not-allowed;
}

textarea.form-control {
    resize: vertical;
    min-height: 100px;
}

select.form-control {
    cursor: pointer;
}

.form-error {
    color: var(--danger-color);
    font-size: 0.875rem;
    margin-top: var(--spacing-xs);
}

.form-help {
    color: var(--text-secondary);
    font-size: 0.875rem;
    margin-top: var(--spacing-xs);
}

/* ============================================
   Tables
   ============================================ */
.table-wrapper {
    overflow-x: auto;
    border-radius: var(--radius-lg);
    box-shadow: var(--shadow-md);
}

.table {
    width: 100%;
    border-collapse: collapse;
    background: var(--bg-primary);
}

.table thead {
    background: var(--bg-tertiary);
}

.table th {
    padding: var(--spacing-md);
    text-align: left;
    font-weight: 700;
    color: var(--text-primary);
    border-bottom: 2px solid var(--border-color);
}

.table td {
    padding: var(--spacing-md);
    border-bottom: 1px solid var(--border-color);
}

.table tbody tr {
    transition: background var(--transition-fast);
}

.table tbody tr:hover {
    background: var(--bg-secondary);
}

.table tbody tr:last-child td {
    border-bottom: none;
}

/* ============================================
   Badges & Status
   ============================================ */
.badge {
    display: inline-block;
    padding: var(--spacing-xs) var(--spacing-sm);
    font-size: 0.75rem;
    font-weight: 600;
    border-radius: var(--radius-sm);
    text-transform: uppercase;
    letter-spacing: 0.5px;
}

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

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

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

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

.in-stock {
    color: var(--success-color);
    font-weight: 600;
}

.low-stock {
    color: var(--warning-color);
    font-weight: 600;
}

.out-of-stock {
    color: var(--danger-color);
    font-weight: 600;
}

/* ============================================
   Alerts & Notifications
   ============================================ */
.alert {
    padding: var(--spacing-md) var(--spacing-lg);
    border-radius: var(--radius-md);
    margin-bottom: var(--spacing-lg);
    display: flex;
    align-items: center;
    gap: var(--spacing-md);
}

.alert-success {
    background: #d1fae5;
    color: #065f46;
    border-left: 4px solid var(--success-color);
}

.alert-warning {
    background: #fef3c7;
    color: #92400e;
    border-left: 4px solid var(--warning-color);
}

.alert-danger {
    background: #fee2e2;
    color: #991b1b;
    border-left: 4px solid var(--danger-color);
}

.alert-info {
    background: #dbeafe;
    color: #1e40af;
    border-left: 4px solid var(--info-color);
}

/* Toast Notifications */
.toast {
    position: fixed;
    top: 20px;
    right: 20px;
    min-width: 300px;
    padding: var(--spacing-md) var(--spacing-lg);
    background: var(--bg-primary);
    border-radius: var(--radius-md);
    box-shadow: var(--shadow-xl);
    z-index: 1000;
    animation: slideInRight 0.3s ease-out;
}

@keyframes slideInRight {
    from {
        transform: translateX(400px);
        opacity: 0;
    }
    to {
        transform: translateX(0);
        opacity: 1;
    }
}

/* ============================================
   Pagination
   ============================================ */
.pagination {
    display: flex;
    gap: var(--spacing-sm);
    justify-content: center;
    margin-top: var(--spacing-xl);
}

.page-link {
    padding: var(--spacing-sm) var(--spacing-md);
    border: 2px solid var(--border-color);
    border-radius: var(--radius-md);
    color: var(--text-primary);
    transition: all var(--transition-fast);
}

.page-link:hover {
    background: var(--primary-color);
    color: white;
    border-color: var(--primary-color);
}

.page-link.active {
    background: var(--primary-color);
    color: white;
    border-color: var(--primary-color);
}

/* ============================================
   Utility Classes
   ============================================ */
.text-center { text-align: center; }
.text-right { text-align: right; }
.text-left { text-align: left; }

.mt-1 { margin-top: var(--spacing-sm); }
.mt-2 { margin-top: var(--spacing-md); }
.mt-3 { margin-top: var(--spacing-lg); }
.mt-4 { margin-top: var(--spacing-xl); }

.mb-1 { margin-bottom: var(--spacing-sm); }
.mb-2 { margin-bottom: var(--spacing-md); }
.mb-3 { margin-bottom: var(--spacing-lg); }
.mb-4 { margin-bottom: var(--spacing-xl); }

.p-1 { padding: var(--spacing-sm); }
.p-2 { padding: var(--spacing-md); }
.p-3 { padding: var(--spacing-lg); }
.p-4 { padding: var(--spacing-xl); }

.d-flex { display: flex; }
.flex-column { flex-direction: column; }
.align-items-center { align-items: center; }
.justify-content-between { justify-content: space-between; }
.justify-content-center { justify-content: center; }
.gap-1 { gap: var(--spacing-sm); }
.gap-2 { gap: var(--spacing-md); }
.gap-3 { gap: var(--spacing-lg); }

.w-100 { width: 100%; }
.h-100 { height: 100%; }

/* ============================================
   Responsive Design
   ============================================ */
@media (max-width: 768px) {
    .navbar {
        padding: var(--spacing-md);
    }
    
    .mobile-menu-toggle {
        display: block;
    }
    
    .nav-menu {
        position: absolute;
        top: 100%;
        left: 0;
        right: 0;
        background: var(--bg-primary);
        flex-direction: column;
        padding: var(--spacing-md);
        box-shadow: var(--shadow-lg);
        display: none;
    }
    
    .nav-menu.active {
        display: flex;
    }
    
    .content-wrapper {
        padding: var(--spacing-md);
    }
    
    .card {
        padding: var(--spacing-md);
    }
    
    .card-header {
        flex-direction: column;
        align-items: flex-start;
        gap: var(--spacing-md);
    }
    
    .table-wrapper {
        font-size: 0.875rem;
    }
    
    .table th,
    .table td {
        padding: var(--spacing-sm);
    }
    
    .btn {
        width: 100%;
        justify-content: center;
    }
    
    .toast {
        left: 20px;
        right: 20px;
        min-width: auto;
    }
}

@media (max-width: 480px) {
    .logo {
        font-size: 1.2rem;
    }
    
    .card-title {
        font-size: 1.2rem;
    }
    
    .table {
        font-size: 0.8rem;
    }
}