/**
 * BuyNiger AI - Multi-Vendor E-Commerce Platform
 * Written by Shuaibu Abdulmumin (08122598372, 07049906420)
 * 
 * Main CSS Design System - Premium Blue Theme
 */

/* =====================================================
   CSS CUSTOM PROPERTIES (DESIGN TOKENS)
   ===================================================== */
:root {
    /* Primary Colors - BuyNiger Blue */
    --primary-50: #eff6ff;
    --primary-100: #dbeafe;
    --primary-200: #bfdbfe;
    --primary-300: #93c5fd;
    --primary-400: #60a5fa;
    --primary-500: #3b82f6;
    --primary-600: #2563eb;
    --primary-700: #1d4ed8;
    --primary-800: #1e40af;
    --primary-900: #1e3a8a;

    /* Secondary Colors */
    --secondary-50: #f8fafc;
    --secondary-100: #f1f5f9;
    --secondary-200: #e2e8f0;
    --secondary-300: #cbd5e1;
    --secondary-400: #94a3b8;
    --secondary-500: #64748b;
    --secondary-600: #475569;
    --secondary-700: #334155;
    --secondary-800: #1e293b;
    --secondary-900: #0f172a;

    /* Accent Colors */
    --success: #10b981;
    --success-light: #d1fae5;
    --warning: #f59e0b;
    --warning-light: #fef3c7;
    --danger: #ef4444;
    --danger-light: #fee2e2;
    --info: #06b6d4;
    --info-light: #cffafe;

    /* Gradients */
    --gradient-primary: linear-gradient(135deg, var(--primary-600) 0%, var(--primary-800) 100%);
    --gradient-hero: linear-gradient(135deg, var(--primary-700) 0%, var(--secondary-900) 100%);
    --gradient-glass: linear-gradient(135deg, rgba(255,255,255,0.1) 0%, rgba(255,255,255,0.05) 100%);

    /* Typography */
    --font-primary: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, sans-serif;
    --font-display: 'Outfit', var(--font-primary);

    /* Spacing */
    --spacing-xs: 0.25rem;
    --spacing-sm: 0.5rem;
    --spacing-md: 1rem;
    --spacing-lg: 1.5rem;
    --spacing-xl: 2rem;
    --spacing-2xl: 3rem;
    --spacing-3xl: 4rem;

    /* Border Radius */
    --radius-sm: 0.375rem;
    --radius-md: 0.5rem;
    --radius-lg: 0.75rem;
    --radius-xl: 1rem;
    --radius-2xl: 1.5rem;
    --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), 0 2px 4px -2px rgb(0 0 0 / 0.1);
    --shadow-lg: 0 10px 15px -3px rgb(0 0 0 / 0.1), 0 4px 6px -4px rgb(0 0 0 / 0.1);
    --shadow-xl: 0 20px 25px -5px rgb(0 0 0 / 0.1), 0 8px 10px -6px rgb(0 0 0 / 0.1);
    --shadow-2xl: 0 25px 50px -12px rgb(0 0 0 / 0.25);
    --shadow-glow: 0 0 40px rgba(59, 130, 246, 0.3);

    /* Transitions */
    --transition-fast: 150ms ease;
    --transition-normal: 300ms ease;
    --transition-slow: 500ms ease;

    /* Z-Index */
    --z-dropdown: 100;
    --z-sticky: 200;
    --z-modal: 300;
    --z-toast: 400;
}

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

html {
    scroll-behavior: smooth;
    font-size: 16px;
}

body {
    font-family: var(--font-primary);
    font-size: 1rem;
    line-height: 1.6;
    color: var(--secondary-800);
    background-color: var(--secondary-50);
    -webkit-font-smoothing: antialiased;
    -moz-osx-font-smoothing: grayscale;
}

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

a {
    color: var(--primary-600);
    text-decoration: none;
    transition: color var(--transition-fast);
}

a:hover {
    color: var(--primary-700);
}

/* =====================================================
   TYPOGRAPHY
   ===================================================== */
h1, h2, h3, h4, h5, h6 {
    font-family: var(--font-display);
    font-weight: 700;
    line-height: 1.2;
    color: var(--secondary-900);
}

h1 { font-size: 2.5rem; }
h2 { font-size: 2rem; }
h3 { font-size: 1.5rem; }
h4 { font-size: 1.25rem; }
h5 { font-size: 1.125rem; }
h6 { font-size: 1rem; }

.text-gradient {
    background: var(--gradient-primary);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
}

/* =====================================================
   BUTTONS
   ===================================================== */
.btn {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    gap: var(--spacing-sm);
    padding: 0.75rem 1.5rem;
    font-family: var(--font-primary);
    font-size: 0.9375rem;
    font-weight: 600;
    line-height: 1;
    text-align: center;
    white-space: nowrap;
    border: none;
    border-radius: var(--radius-lg);
    cursor: pointer;
    transition: all var(--transition-fast);
}

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

.btn-primary {
    background: var(--gradient-primary);
    color: white;
    box-shadow: var(--shadow-md), 0 0 0 0 rgba(59, 130, 246, 0.5);
}

.btn-primary:hover:not(:disabled) {
    transform: translateY(-2px);
    box-shadow: var(--shadow-lg), 0 0 20px rgba(59, 130, 246, 0.4);
}

.btn-primary:active:not(:disabled) {
    transform: translateY(0);
}

.btn-secondary {
    background: white;
    color: var(--secondary-700);
    border: 1px solid var(--secondary-200);
    box-shadow: var(--shadow-sm);
}

.btn-secondary:hover:not(:disabled) {
    background: var(--secondary-50);
    border-color: var(--secondary-300);
}

.btn-outline {
    background: transparent;
    color: var(--primary-600);
    border: 2px solid var(--primary-600);
}

.btn-outline:hover:not(:disabled) {
    background: var(--primary-600);
    color: white;
}

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

.btn-success:hover:not(:disabled) {
    background: #059669;
}

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

.btn-danger:hover:not(:disabled) {
    background: #dc2626;
}

.btn-lg {
    padding: 1rem 2rem;
    font-size: 1rem;
}

.btn-sm {
    padding: 0.5rem 1rem;
    font-size: 0.875rem;
}

.btn-full {
    width: 100%;
}

.btn-icon {
    padding: 0.75rem;
    border-radius: var(--radius-md);
}

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

.form-label {
    display: block;
    margin-bottom: var(--spacing-sm);
    font-size: 0.875rem;
    font-weight: 600;
    color: var(--secondary-700);
}

.form-input,
.form-select,
.form-textarea {
    width: 100%;
    padding: 0.875rem 1rem;
    font-family: var(--font-primary);
    font-size: 1rem;
    color: var(--secondary-800);
    background: white;
    border: 1.5px solid var(--secondary-200);
    border-radius: var(--radius-lg);
    transition: all var(--transition-fast);
}

.form-input:focus,
.form-select:focus,
.form-textarea:focus {
    outline: none;
    border-color: var(--primary-500);
    box-shadow: 0 0 0 4px rgba(59, 130, 246, 0.1);
}

.form-input::placeholder {
    color: var(--secondary-400);
}

.form-input.error {
    border-color: var(--danger);
}

.form-input.error:focus {
    box-shadow: 0 0 0 4px rgba(239, 68, 68, 0.1);
}

.form-error {
    margin-top: var(--spacing-xs);
    font-size: 0.8125rem;
    color: var(--danger);
}

.form-help {
    margin-top: var(--spacing-xs);
    font-size: 0.8125rem;
    color: var(--secondary-500);
}

.form-checkbox {
    display: flex;
    align-items: center;
    gap: var(--spacing-sm);
    cursor: pointer;
}

.form-checkbox input[type="checkbox"] {
    width: 1.25rem;
    height: 1.25rem;
    accent-color: var(--primary-600);
    cursor: pointer;
}

/* =====================================================
   CARDS
   ===================================================== */
.card {
    background: white;
    border-radius: var(--radius-xl);
    box-shadow: var(--shadow-md);
    overflow: hidden;
}

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

.card-header {
    padding: var(--spacing-lg) var(--spacing-xl);
    border-bottom: 1px solid var(--secondary-100);
}

.card-footer {
    padding: var(--spacing-lg) var(--spacing-xl);
    border-top: 1px solid var(--secondary-100);
    background: var(--secondary-50);
}

.card-glass {
    background: var(--gradient-glass);
    backdrop-filter: blur(12px);
    border: 1px solid rgba(255, 255, 255, 0.2);
}

/* =====================================================
   AUTH LAYOUT
   ===================================================== */
.auth-container {
    min-height: 100vh;
    display: flex;
}

.auth-left {
    flex: 1;
    display: flex;
    align-items: center;
    justify-content: center;
    padding: var(--spacing-2xl);
    background: white;
}

.auth-right {
    flex: 1;
    display: none;
    background: var(--gradient-hero);
    position: relative;
    overflow: hidden;
}

@media (min-width: 1024px) {
    .auth-right {
        display: flex;
        align-items: center;
        justify-content: center;
    }
}

.auth-right-content {
    position: relative;
    z-index: 1;
    text-align: center;
    color: white;
    padding: var(--spacing-2xl);
    max-width: 500px;
}

.auth-right-content h2 {
    color: white;
    font-size: 2.5rem;
    margin-bottom: var(--spacing-lg);
}

.auth-right-content p {
    font-size: 1.125rem;
    opacity: 0.9;
    line-height: 1.7;
}

/* Animated background shapes */
.auth-right::before {
    content: '';
    position: absolute;
    width: 400px;
    height: 400px;
    background: rgba(255, 255, 255, 0.1);
    border-radius: 50%;
    top: -100px;
    right: -100px;
    animation: float 8s ease-in-out infinite;
}

.auth-right::after {
    content: '';
    position: absolute;
    width: 300px;
    height: 300px;
    background: rgba(255, 255, 255, 0.05);
    border-radius: 50%;
    bottom: -50px;
    left: -50px;
    animation: float 10s ease-in-out infinite reverse;
}

@keyframes float {
    0%, 100% { transform: translateY(0) rotate(0deg); }
    50% { transform: translateY(-30px) rotate(5deg); }
}

.auth-box {
    width: 100%;
    max-width: 440px;
}

.auth-logo {
    text-align: center;
    margin-bottom: var(--spacing-2xl);
}

.auth-logo img {
    height: 48px;
    margin: 0 auto;
}

.auth-logo h1 {
    font-size: 1.75rem;
    color: var(--primary-700);
    margin-top: var(--spacing-md);
}

.auth-title {
    text-align: center;
    margin-bottom: var(--spacing-xl);
}

.auth-title h2 {
    font-size: 1.75rem;
    margin-bottom: var(--spacing-sm);
}

.auth-title p {
    color: var(--secondary-500);
}

.auth-divider {
    display: flex;
    align-items: center;
    text-align: center;
    margin: var(--spacing-xl) 0;
    color: var(--secondary-400);
    font-size: 0.875rem;
}

.auth-divider::before,
.auth-divider::after {
    content: '';
    flex: 1;
    height: 1px;
    background: var(--secondary-200);
}

.auth-divider::before {
    margin-right: var(--spacing-md);
}

.auth-divider::after {
    margin-left: var(--spacing-md);
}

.auth-footer {
    text-align: center;
    margin-top: var(--spacing-xl);
    font-size: 0.9375rem;
    color: var(--secondary-600);
}

.auth-footer a {
    font-weight: 600;
}

/* =====================================================
   ALERTS
   ===================================================== */
.alert {
    display: flex;
    align-items: flex-start;
    gap: var(--spacing-md);
    padding: var(--spacing-md) var(--spacing-lg);
    border-radius: var(--radius-lg);
    margin-bottom: var(--spacing-lg);
    font-size: 0.9375rem;
}

.alert-success {
    background: var(--success-light);
    color: #065f46;
    border: 1px solid #a7f3d0;
}

.alert-error {
    background: var(--danger-light);
    color: #991b1b;
    border: 1px solid #fca5a5;
}

.alert-warning {
    background: var(--warning-light);
    color: #92400e;
    border: 1px solid #fcd34d;
}

.alert-info {
    background: var(--info-light);
    color: #0e7490;
    border: 1px solid #67e8f9;
}

/* =====================================================
   UTILITIES
   ===================================================== */
.container {
    width: 100%;
    max-width: 1280px;
    margin: 0 auto;
    padding: 0 var(--spacing-lg);
}

.text-center { text-align: center; }
.text-right { text-align: right; }

.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); }

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

.hidden { display: none; }

@media (min-width: 768px) {
    .md\:flex { display: flex; }
    .md\:hidden { display: none; }
}

/* =====================================================
   LOADING SPINNER
   ===================================================== */
.spinner {
    width: 24px;
    height: 24px;
    border: 3px solid rgba(255, 255, 255, 0.3);
    border-top-color: white;
    border-radius: 50%;
    animation: spin 0.8s linear infinite;
}

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

/* =====================================================
   PASSWORD TOGGLE
   ===================================================== */
.password-wrapper {
    position: relative;
}

.password-toggle {
    position: absolute;
    right: 1rem;
    top: 50%;
    transform: translateY(-50%);
    background: none;
    border: none;
    color: var(--secondary-400);
    cursor: pointer;
    padding: 0.25rem;
    transition: color var(--transition-fast);
}

.password-toggle:hover {
    color: var(--secondary-600);
}