/* LOTUS ELECTRONICS - Professional Static Website Styles */
/* Mobile-first responsive design with accessibility features */

/* CSS Reset and Base Styles */
*,
*::before,
*::after {
    box-sizing: border-box;
    margin: 0;
    padding: 0;
}

:root {
    /* Color Palette - Professional Electronics Theme */
    --primary-color: #1e40af; /* Deep blue */
    --primary-dark: #1e3a8a;
    --primary-light: #3b82f6;
    --secondary-color: #059669; /* Green accent */
    --secondary-dark: #047857;
    --accent-color: #f59e0b; /* Amber */
    --accent-dark: #d97706;
    
    /* Neutral Colors */
    --text-primary: #1f2937;
    --text-secondary: #6b7280;
    --text-light: #9ca3af;
    --bg-primary: #ffffff;
    --bg-secondary: #f9fafb;
    --bg-dark: #111827;
    --border-color: #e5e7eb;
    --border-dark: #d1d5db;
    
    /* Typography */
    --font-primary: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
    --font-secondary: Georgia, 'Times New Roman', serif;
    
    /* 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;
    
    /* Layout */
    --container-max: 1200px;
    --border-radius: 0.5rem;
    --border-radius-lg: 1rem;
    --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);
    
    /* Transitions */
    --transition-fast: 0.15s ease-in-out;
    --transition-normal: 0.3s ease-in-out;
    --transition-slow: 0.5s ease-in-out;
}

/* Respect user motion preferences */
@media (prefers-reduced-motion: reduce) {
    *,
    *::before,
    *::after {
        animation-duration: 0.01ms !important;
        animation-iteration-count: 1 !important;
        transition-duration: 0.01ms !important;
    }
}

/* Base Typography */
html {
    font-size: 16px;
    scroll-behavior: smooth;
}

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

/* Skip Link for Accessibility */
.skip-link {
    position: absolute;
    top: -40px;
    left: 6px;
    background: var(--primary-color);
    color: white;
    padding: 8px;
    text-decoration: none;
    border-radius: var(--border-radius);
    z-index: 1000;
    font-weight: 600;
}

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

/* Typography Scale */
h1, h2, h3, h4, h5, h6 {
    font-weight: 700;
    line-height: 1.2;
    margin-bottom: var(--spacing-md);
    color: var(--text-primary);
}

h1 {
    font-size: 2.25rem;
    margin-bottom: var(--spacing-lg);
}

h2 {
    font-size: 1.875rem;
    margin-bottom: var(--spacing-lg);
}

h3 {
    font-size: 1.5rem;
}

h4 {
    font-size: 1.25rem;
}

h5 {
    font-size: 1.125rem;
}

h6 {
    font-size: 1rem;
}

p {
    margin-bottom: var(--spacing-md);
    color: var(--text-secondary);
}

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

a:hover,
a:focus {
    color: var(--primary-dark);
    text-decoration: underline;
}

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

/* Lists */
ul, ol {
    margin-bottom: var(--spacing-md);
    padding-left: var(--spacing-xl);
}

li {
    margin-bottom: var(--spacing-sm);
    color: var(--text-secondary);
}

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

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

.section {
    padding: var(--spacing-3xl) 0;
}

.section-sm {
    padding: var(--spacing-2xl) 0;
}

.section-lg {
    padding: var(--spacing-3xl) 0 calc(var(--spacing-3xl) * 1.5);
}

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

.grid-2 {
    grid-template-columns: 1fr;
}

.grid-3 {
    grid-template-columns: 1fr;
}

.grid-4 {
    grid-template-columns: 1fr;
}

/* Buttons */
.btn {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    padding: var(--spacing-md) var(--spacing-xl);
    font-size: 1rem;
    font-weight: 600;
    text-decoration: none;
    border: none;
    border-radius: var(--border-radius);
    cursor: pointer;
    transition: all var(--transition-fast);
    min-height: 44px; /* Accessibility - minimum touch target */
    gap: var(--spacing-sm);
}

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

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

.btn-primary:hover,
.btn-primary:focus {
    background-color: var(--primary-dark);
    color: white;
    text-decoration: none;
    transform: translateY(-1px);
    box-shadow: var(--shadow-md);
}

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

.btn-secondary:hover,
.btn-secondary:focus {
    background-color: var(--secondary-dark);
    color: white;
    text-decoration: none;
    transform: translateY(-1px);
    box-shadow: var(--shadow-md);
}

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

.btn-outline:hover,
.btn-outline:focus {
    background-color: var(--primary-color);
    color: white;
    text-decoration: none;
}

.btn-lg {
    padding: var(--spacing-lg) var(--spacing-2xl);
    font-size: 1.125rem;
}

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

.card:hover {
    transform: translateY(-4px);
    box-shadow: var(--shadow-lg);
}

.card-header {
    margin-bottom: var(--spacing-lg);
}

.card-title {
    font-size: 1.25rem;
    font-weight: 600;
    margin-bottom: var(--spacing-sm);
}

.card-text {
    color: var(--text-secondary);
    margin-bottom: var(--spacing-lg);
}

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

.header-content {
    display: flex;
    align-items: center;
    justify-content: space-between;
    padding: var(--spacing-md) 0;
}

.logo {
    font-size: 1.5rem;
    font-weight: 700;
    color: var(--primary-color);
    text-decoration: none;
}

.logo:hover,
.logo:focus {
    color: var(--primary-dark);
    text-decoration: none;
}

/* Navigation */
.nav {
    display: flex;
    align-items: center;
    gap: var(--spacing-lg);
}

.nav-menu {
    display: none;
    list-style: none;
    margin: 0;
    padding: 0;
    gap: var(--spacing-lg);
}

.nav-menu.active {
    display: flex;
    position: absolute;
    top: 100%;
    left: 0;
    right: 0;
    background: var(--bg-primary);
    flex-direction: column;
    padding: var(--spacing-lg);
    box-shadow: var(--shadow-md);
    gap: var(--spacing-md);
}

.nav-link {
    color: var(--text-primary);
    font-weight: 500;
    padding: var(--spacing-sm) 0;
    transition: color var(--transition-fast);
}

.nav-link:hover,
.nav-link:focus {
    color: var(--primary-color);
    text-decoration: none;
}

.nav-link.active {
    color: var(--primary-color);
    font-weight: 600;
}

/* Mobile Menu Toggle */
.menu-toggle {
    display: flex;
    flex-direction: column;
    gap: 4px;
    background: none;
    border: none;
    cursor: pointer;
    padding: var(--spacing-sm);
    width: 44px;
    height: 44px;
    align-items: center;
    justify-content: center;
}

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

.menu-toggle span {
    width: 24px;
    height: 3px;
    background: var(--text-primary);
    transition: all var(--transition-fast);
}

.menu-toggle.active span:nth-child(1) {
    transform: rotate(45deg) translate(5px, 5px);
}

.menu-toggle.active span:nth-child(2) {
    opacity: 0;
}

.menu-toggle.active span:nth-child(3) {
    transform: rotate(-45deg) translate(7px, -6px);
}

/* Hero Section */
.hero {
    background: linear-gradient(135deg, var(--primary-color) 0%, var(--primary-dark) 100%);
    color: white;
    text-align: center;
    padding: var(--spacing-3xl) 0;
}

.hero-content {
    max-width: 800px;
    margin: 0 auto;
}

.hero h1 {
    color: white;
    font-size: 2.5rem;
    margin-bottom: var(--spacing-lg);
}

.hero p {
    font-size: 1.25rem;
    color: rgba(255, 255, 255, 0.9);
    margin-bottom: var(--spacing-2xl);
}

.hero-cta {
    display: flex;
    flex-direction: column;
    gap: var(--spacing-md);
    align-items: center;
}

/* Features/Services Grid */
.features {
    background: var(--bg-secondary);
}

.feature-card {
    text-align: center;
    padding: var(--spacing-2xl) var(--spacing-lg);
}

.feature-icon {
    width: 64px;
    height: 64px;
    background: var(--primary-color);
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    margin: 0 auto var(--spacing-lg);
    font-size: 1.5rem;
    color: white;
}

/* Testimonials */
.testimonial {
    background: var(--bg-primary);
    border-radius: var(--border-radius-lg);
    padding: var(--spacing-xl);
    text-align: center;
    box-shadow: var(--shadow-sm);
}

.testimonial-text {
    font-style: italic;
    font-size: 1.125rem;
    margin-bottom: var(--spacing-lg);
    color: var(--text-secondary);
}

.testimonial-author {
    font-weight: 600;
    color: var(--text-primary);
}

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

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

.form-label.required::after {
    content: " *";
    color: #dc2626;
}

.form-input,
.form-select,
.form-textarea {
    width: 100%;
    padding: var(--spacing-md);
    border: 2px solid var(--border-color);
    border-radius: var(--border-radius);
    font-size: 1rem;
    font-family: inherit;
    transition: border-color var(--transition-fast);
    min-height: 44px;
}

.form-input:focus,
.form-select:focus,
.form-textarea:focus {
    outline: none;
    border-color: var(--primary-color);
    box-shadow: 0 0 0 3px rgba(59, 130, 246, 0.1);
}

.form-input.error,
.form-select.error,
.form-textarea.error {
    border-color: #dc2626;
}

.form-textarea {
    resize: vertical;
    min-height: 120px;
}

.form-error {
    color: #dc2626;
    font-size: 0.875rem;
    margin-top: var(--spacing-xs);
    display: none;
}

.form-error.show {
    display: block;
}

/* Checkbox styling */
.checkbox-group {
    display: flex;
    align-items: flex-start;
    gap: var(--spacing-sm);
    margin-bottom: var(--spacing-md);
}

.checkbox-input {
    width: auto;
    min-height: auto;
    margin: 0;
}

.checkbox-label {
    font-weight: normal;
    margin: 0;
    font-size: 0.875rem;
    line-height: 1.4;
    cursor: pointer;
}

/* Footer */
.footer {
    background: var(--bg-dark);
    color: white;
    padding: var(--spacing-3xl) 0 var(--spacing-xl);
}

.footer-content {
    display: grid;
    gap: var(--spacing-2xl);
    margin-bottom: var(--spacing-2xl);
}

.footer-section h3 {
    color: white;
    margin-bottom: var(--spacing-lg);
}

.footer-section p,
.footer-section li {
    color: rgba(255, 255, 255, 0.8);
}

.footer-section a {
    color: rgba(255, 255, 255, 0.8);
}

.footer-section a:hover,
.footer-section a:focus {
    color: white;
}

.footer-bottom {
    border-top: 1px solid rgba(255, 255, 255, 0.1);
    padding-top: var(--spacing-lg);
    text-align: center;
    color: rgba(255, 255, 255, 0.6);
}

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

.mb-0 { margin-bottom: 0; }
.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); }

.mt-0 { margin-top: 0; }
.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); }

.hidden { display: none; }
.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;
}

/* Loading States */
.loading {
    opacity: 0.6;
    pointer-events: none;
}

.spinner {
    display: inline-block;
    width: 20px;
    height: 20px;
    border: 2px solid rgba(255, 255, 255, 0.3);
    border-radius: 50%;
    border-top-color: white;
    animation: spin 1s ease-in-out infinite;
}

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

/* Success/Error Messages */
.alert {
    padding: var(--spacing-md);
    border-radius: var(--border-radius);
    margin-bottom: var(--spacing-lg);
    font-weight: 500;
}

.alert-success {
    background-color: #d1fae5;
    color: #065f46;
    border: 1px solid #a7f3d0;
}

.alert-error {
    background-color: #fee2e2;
    color: #991b1b;
    border: 1px solid #fca5a5;
}

/* Responsive Design - Tablet */
@media (min-width: 768px) {
    .container {
        padding: 0 var(--spacing-xl);
    }
    
    .grid-2 {
        grid-template-columns: repeat(2, 1fr);
    }
    
    .grid-3 {
        grid-template-columns: repeat(2, 1fr);
    }
    
    .hero h1 {
        font-size: 3rem;
    }
    
    .hero-cta {
        flex-direction: row;
        justify-content: center;
    }
    
    .nav-menu {
        display: flex;
        position: static;
        background: none;
        flex-direction: row;
        padding: 0;
        box-shadow: none;
    }
    
    .menu-toggle {
        display: none;
    }
    
    .footer-content {
        grid-template-columns: repeat(2, 1fr);
    }
}

/* Responsive Design - Desktop */
@media (min-width: 1024px) {
    .grid-3 {
        grid-template-columns: repeat(3, 1fr);
    }
    
    .grid-4 {
        grid-template-columns: repeat(4, 1fr);
    }
    
    .hero h1 {
        font-size: 3.5rem;
    }
    
    .footer-content {
        grid-template-columns: repeat(4, 1fr);
    }
    
    .section {
        padding: calc(var(--spacing-3xl) * 1.5) 0;
    }
}

/* High Contrast Mode Support */
@media (prefers-contrast: high) {
    :root {
        --border-color: #000000;
        --text-secondary: #000000;
    }
}

/* Print Styles */
@media print {
    .header,
    .footer,
    .btn,
    .menu-toggle {
        display: none;
    }
    
    .section {
        padding: var(--spacing-lg) 0;
    }
    
    a {
        text-decoration: underline;
    }
    
    .card {
        box-shadow: none;
        border: 1px solid var(--border-color);
    }
}