/**
 * Net View Security - Main Stylesheet
 * Design System & Global Styles
 */

/* ===== CSS VARIABLES (Design System) ===== */
:root {
    /* Colors */
    --color-primary: #1E3A8A;
    --color-secondary: #3B82F6;
    --color-accent: #F59E0B;
    --color-dark: #1F2937;
    --color-light: #F9FAFB;
    --color-success: #10B981;
    --color-white: #FFFFFF;
    --color-gray-100: #F3F4F6;
    --color-gray-200: #E5E7EB;
    --color-gray-300: #D1D5DB;
    --color-gray-600: #4B5563;
    --color-gray-800: #1F2937;
    
    /* Typography */
    --font-primary: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', sans-serif;
    --font-heading: 'Poppins', 'Inter', sans-serif;
    
    /* Font Sizes */
    --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 */
    --text-4xl: 2.25rem;    /* 36px */
    --text-5xl: 3rem;       /* 48px */
    --text-6xl: 3.75rem;    /* 60px */
    
    /* Line Heights */
    --leading-tight: 1.25;
    --leading-snug: 1.375;
    --leading-normal: 1.5;
    --leading-relaxed: 1.625;
    --leading-loose: 2;
    
    /* Spacing */
    --spacing-1: 0.25rem;   /* 4px */
    --spacing-2: 0.5rem;    /* 8px */
    --spacing-3: 0.75rem;   /* 12px */
    --spacing-4: 1rem;      /* 16px */
    --spacing-5: 1.25rem;   /* 20px */
    --spacing-6: 1.5rem;    /* 24px */
    --spacing-8: 2rem;      /* 32px */
    --spacing-10: 2.5rem;   /* 40px */
    --spacing-12: 3rem;     /* 48px */
    --spacing-16: 4rem;     /* 64px */
    --spacing-20: 5rem;     /* 80px */
    --spacing-24: 6rem;     /* 96px */
    
    /* Border Radius */
    --radius-sm: 0.25rem;   /* 4px */
    --radius-md: 0.5rem;    /* 8px */
    --radius-lg: 0.75rem;   /* 12px */
    --radius-xl: 1rem;      /* 16px */
    --radius-full: 9999px;
    
    /* Shadows */
    --shadow-sm: 0 1px 2px 0 rgba(0, 0, 0, 0.05);
    --shadow-md: 0 4px 6px -1px rgba(0, 0, 0, 0.07), 0 2px 4px -1px rgba(0, 0, 0, 0.03);
    --shadow-lg: 0 10px 15px -3px rgba(0, 0, 0, 0.08), 0 4px 6px -2px rgba(0, 0, 0, 0.03);
    --shadow-xl: 0 20px 25px -5px rgba(0, 0, 0, 0.1), 0 10px 10px -5px rgba(0, 0, 0, 0.04);
    
    /* Transitions */
    --transition-fast: 150ms ease;
    --transition-base: 200ms ease;
    --transition-slow: 300ms ease;
    
    /* Container */
    --container-max: 1280px;
    --container-padding: var(--spacing-4);
}

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

html {
    scroll-behavior: smooth;
}

body {
    font-family: var(--font-primary);
    font-size: var(--text-base);
    line-height: var(--leading-relaxed);
    color: var(--color-dark);
    background-color: var(--color-white);
    margin: 0;
    padding: 0;
    overflow-x: hidden;
    -webkit-font-smoothing: antialiased;
    -moz-osx-font-smoothing: grayscale;
}

/* Prevent scrolling when mobile menu is open */
body.no-scroll {
    overflow: hidden;
    position: fixed;
    width: 100%;
}

/* ===== TYPOGRAPHY ===== */
h1, h2, h3, h4, h5, h6 {
    font-family: var(--font-heading);
    font-weight: 700;
    line-height: var(--leading-tight);
    margin-bottom: var(--spacing-4);
    color: var(--color-dark);
    letter-spacing: -0.02em;
}

h1 { font-size: var(--text-5xl); }
h2 { font-size: var(--text-4xl); }
h3 { font-size: var(--text-3xl); }
h4 { font-size: var(--text-2xl); }
h5 { font-size: var(--text-xl); }
h6 { font-size: var(--text-lg); }

p {
    margin-bottom: var(--spacing-4);
    line-height: var(--leading-relaxed);
}

p:last-child {
    margin-bottom: 0;
}

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

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

/* ===== UTILITY CLASSES ===== */
.container {
    max-width: var(--container-max);
    margin: 0 auto;
    padding: 0 var(--container-padding);
}

.container-wide {
    max-width: 1440px;
    margin: 0 auto;
    padding: 0 var(--container-padding);
}

.section {
    padding: var(--spacing-20) 0;
}

.section-lg {
    padding: var(--spacing-24) 0;
}

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

.text-primary { color: var(--color-primary); }
.text-secondary { color: var(--color-secondary); }
.text-accent { color: var(--color-accent); }
.text-white { color: var(--color-white); }

.bg-primary { background-color: var(--color-primary); }
.bg-secondary { background-color: var(--color-secondary); }
.bg-light { background-color: var(--color-light); }
.bg-dark { background-color: var(--color-dark); }

/* ===== BUTTONS ===== */
.btn {
    display: inline-block;
    padding: 0.75rem 2rem;
    font-size: var(--text-base);
    font-weight: 600;
    text-align: center;
    border-radius: var(--radius-md);
    border: 2px solid transparent;
    cursor: pointer;
    transition: all var(--transition-base);
    text-decoration: none;
    line-height: 1.5;
    position: relative;
    overflow: hidden;
    white-space: nowrap;
}

.btn::before {
    content: '';
    position: absolute;
    top: 50%;
    left: 50%;
    width: 0;
    height: 0;
    border-radius: 50%;
    background: rgba(255, 255, 255, 0.2);
    transform: translate(-50%, -50%);
    transition: width 0.6s, height 0.6s;
}

.btn:hover::before {
    width: 300px;
    height: 300px;
}

.btn > * {
    position: relative;
    z-index: 1;
}

.btn-primary {
    background-color: var(--color-primary);
    color: #FFFFFF !important;
    border-color: var(--color-primary);
}

.btn-primary:hover {
    background-color: #1e40af;
    border-color: #1e40af;
    transform: translateY(-2px);
    box-shadow: 0 8px 16px rgba(30, 58, 138, 0.25);
}

.btn-primary:active {
    transform: translateY(0);
    box-shadow: 0 4px 8px rgba(30, 58, 138, 0.3);
}

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

.btn-secondary:hover {
    background-color: #2563eb;
    border-color: #2563eb;
    transform: translateY(-2px);
    box-shadow: 0 8px 16px rgba(37, 99, 235, 0.25);
}

.btn-secondary:active {
    transform: translateY(0);
    box-shadow: 0 4px 8px rgba(37, 99, 235, 0.3);
}

.btn-accent {
    background-color: var(--color-accent);
    color: #FFFFFF !important;
    border-color: var(--color-accent);
}

.btn-accent:hover {
    background-color: #d97706;
    border-color: #d97706;
    color: #FFFFFF !important;
    transform: translateY(-2px);
    box-shadow: 0 8px 16px rgba(245, 158, 11, 0.3);
}

.btn-accent:active {
    transform: translateY(0);
    box-shadow: 0 4px 8px rgba(245, 158, 11, 0.3);
    color: #FFFFFF !important;
}

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

.btn-outline:hover {
    background-color: var(--color-primary);
    color: var(--color-white);
    transform: translateY(-2px);
    box-shadow: 0 8px 16px rgba(30, 58, 138, 0.3);
}

.btn-outline:active {
    transform: translateY(0);
}

.btn-lg {
    padding: 1rem 2.5rem;
    font-size: var(--text-lg);
}

/* ===== GRID SYSTEM ===== */
.grid {
    display: grid;
    gap: var(--spacing-6);
}

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

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

.grid-4 {
    grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
}

/* ===== CARDS ===== */
.card {
    background: var(--color-white);
    border-radius: var(--radius-lg);
    padding: var(--spacing-6);
    box-shadow: var(--shadow-md);
    transition: all var(--transition-base);
    border: 1px solid var(--color-gray-200);
}

.card:hover {
    transform: translateY(-4px);
    box-shadow: var(--shadow-xl);
    border-color: var(--color-secondary);
}

/* ===== RESPONSIVE ===== */
@media (max-width: 768px) {
    :root {
        --text-5xl: 2.5rem;     /* 40px on mobile */
        --text-4xl: 2rem;       /* 32px on mobile */
        --text-3xl: 1.5rem;     /* 24px on mobile */
        --spacing-20: 3rem;     /* 48px on mobile */
        --spacing-24: 4rem;     /* 64px on mobile */
    }
    
    .grid-3 {
        grid-template-columns: repeat(2, 1fr);
    }
    
    .grid-2,
    .grid-4 {
        grid-template-columns: 1fr;
    }
}

@media (max-width: 640px) {
    .grid-2,
    .grid-3,
    .grid-4 {
        grid-template-columns: 1fr;
    }
}

@media (max-width: 480px) {
    :root {
        --container-padding: var(--spacing-3);
    }
    
    .btn-lg {
        padding: var(--spacing-3) var(--spacing-6);
        font-size: var(--text-base);
    }
}

/* ===== ANIMATIONS ===== */
@keyframes fadeIn {
    from {
        opacity: 0;
        transform: translateY(20px);
    }
    to {
        opacity: 1;
        transform: translateY(0);
    }
}

.fade-in {
    animation: fadeIn 0.6s ease-out;
}

/* ===== ACCESSIBILITY ===== */
.sr-only {
    position: absolute;
    width: 1px;
    height: 1px;
    padding: 0;
    margin: -1px;
    overflow: hidden;
    clip: rect(0, 0, 0, 0);
    white-space: nowrap;
    border-width: 0;
}

/* Focus styles for keyboard navigation */
a:focus,
button:focus,
input:focus,
textarea:focus {
    outline: 2px solid var(--color-secondary);
    outline-offset: 2px;
}