:root {
    /* Color System */
    --color-primary-900: #0d2b4b;
    --color-primary-800: #1a365d;
    --color-primary-700: #2a4a73;
    --color-primary-600: #385d8a;
    --color-primary-500: #4a72a0;
    --color-primary-400: #6d8cb1;
    --color-primary-300: #91a9c7;
    --color-primary-200: #b6c6dd;
    --color-primary-100: #dce4f0;
    --color-primary-50: #eef3f8;

    --color-accent-900: #1e484b;
    --color-accent-800: #2c7a7b;
    --color-accent-700: #38a89d;
    --color-accent-600: #4fd1c5;
    --color-accent-500: #81e6d9;
    --color-accent-400: #9feeea;
    --color-accent-300: #b2f5ea;
    --color-accent-200: #c4f1f9;
    --color-accent-100: #e6fffa;
    --color-accent-50: #f0ffff;

    --color-highlight-900: #9b1c1c;
    --color-highlight-800: #c53030;
    --color-highlight-700: #e53e3e;
    --color-highlight-600: #f56565;
    --color-highlight-500: #fc8181;
    --color-highlight-400: #feb2b2;
    --color-highlight-300: #fbd5d5;
    --color-highlight-200: #fed7d7;
    --color-highlight-100: #fff5f5;
    --color-highlight-50: #fffafa;

    --color-success: #38a169;
    --color-warning: #d69e2e;
    --color-error: #e53e3e;

    --color-gray-900: #1a202c;
    --color-gray-800: #2d3748;
    --color-gray-700: #4a5568;
    --color-gray-600: #718096;
    --color-gray-500: #a0aec0;
    --color-gray-400: #cbd5e0;
    --color-gray-300: #e2e8f0;
    --color-gray-200: #edf2f7;
    --color-gray-100: #f7fafc;
    --color-white: #ffffff;

    /* Typography */
    --font-family-base: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, Oxygen-Sans, Ubuntu, Cantarell, 'Helvetica Neue', sans-serif;
    --font-family-heading: var(--font-family-base);

    /* Spacing System - based on 8px */
    --space-1: 0.25rem;  /* 4px */
    --space-2: 0.5rem;   /* 8px */
    --space-3: 1rem;     /* 16px */
    --space-4: 1.5rem;   /* 24px */
    --space-5: 2rem;     /* 32px */
    --space-6: 3rem;     /* 48px */
    --space-7: 4rem;     /* 64px */
    --space-8: 6rem;     /* 96px */
    --space-9: 8rem;     /* 128px */

    /* Breakpoints */
    --breakpoint-sm: 640px;
    --breakpoint-md: 768px;
    --breakpoint-lg: 1024px;
    --breakpoint-xl: 1280px;

    /* Base styles */
    --body-bg: var(--color-gray-100);
    --text-color: var(--color-gray-800);
    --link-color: var(--color-primary-700);
    --link-hover-color: var(--color-primary-900);
    --heading-color: var(--color-primary-900);

    /* Container widths */
    --container-max-width: 1200px;
    --container-padding: var(--space-4);

    /* 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);

    /* Border radius */
    --radius-sm: 0.25rem;
    --radius-md: 0.375rem;
    --radius-lg: 0.5rem;
    --radius-xl: 1rem;
    --radius-full: 9999px;

    /* Z-index layers */
    --z-below: -1;
    --z-normal: 1;
    --z-above: 10;
    --z-modal: 100;
    --z-toast: 1000;
    --z-max: 9999;

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

/* Base styles */
@import url('https://fonts.googleapis.com/css2?family=Inter:wght@300;400;500;600;700&display=swap');

*, *::before, *::after {
    box-sizing: border-box;
}

html {
    font-size: 18px;
    scroll-behavior: smooth;
}

body {
    font-family: var(--font-family-base);
    color: var(--text-color);
    background-color: var(--body-bg);
    line-height: 1.5;
    font-weight: 400;
    margin: 0;
    padding: 0;
    min-height: 100vh;
    display: flex;
    flex-direction: column;
}

main {
    flex: 1;
}

/* Typography */
h1, h2, h3, h4, h5, h6 {
    font-family: var(--font-family-heading);
    color: var(--heading-color);
    line-height: 1.2;
    margin-top: 0;
    margin-bottom: var(--space-3);
    font-weight: 700;
}

h1 {
    font-size: 2.25rem;
}

h2 {
    font-size: 1.875rem;
    margin-top: var(--space-6);
}

h3 {
    font-size: 1.5rem;
    margin-top: var(--space-5);
}

h4 {
    font-size: 1.25rem;
}

p {
    margin-top: 0;
    margin-bottom: var(--space-3);
}

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

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

.lead {
    font-size: 1.125rem;
    font-weight: 400;
    color: var(--color-gray-700);
}

ul, ol {
    margin-top: 0;
    margin-bottom: var(--space-3);
    padding-left: var(--space-4);
}

li {
    margin-bottom: var(--space-2);
}

/* Container */
.container {
    width: 100%;
    max-width: var(--container-max-width);
    margin-left: auto;
    margin-right: auto;
    padding-left: var(--container-padding);
    padding-right: var(--container-padding);
}

/* Header */
.site-header {
    background-color: var(--color-white);
    box-shadow: var(--shadow-sm);
    padding: var(--space-3) 0;
    position: sticky;
    top: 0;
    z-index: var(--z-above);
    transition: background-color var(--transition-normal) ease, box-shadow var(--transition-normal) ease;
}

.site-header .container {
    display: flex;
    justify-content: space-between;
    align-items: center;
}

.site-branding {
    display: flex;
    align-items: center;
}

.site-title {
    font-size: 1.5rem;
    font-weight: 700;
    color: var(--color-primary-800);
    letter-spacing: -0.025em;
}

.site-title:hover {
    color: var(--color-primary-900);
}

/* Navigation */
.main-navigation ul {
    display: none;
    list-style: none;
    margin: 0;
    padding: 0;
}

.menu-toggle {
    display: block;
    background: none;
    border: none;
    padding: var(--space-2);
    cursor: pointer;
}

.hamburger {
    display: block;
    position: relative;
    width: 24px;
    height: 2px;
    background-color: var(--color-primary-800);
}

.hamburger::before,
.hamburger::after {
    content: '';
    position: absolute;
    width: 24px;
    height: 2px;
    background-color: var(--color-primary-800);
    transition: transform var(--transition-fast) ease;
}

.hamburger::before {
    top: -8px;
}

.hamburger::after {
    bottom: -8px;
}

.menu-toggle[aria-expanded="true"] .hamburger {
    background-color: transparent;
}

.menu-toggle[aria-expanded="true"] .hamburger::before {
    transform: translateY(8px) rotate(45deg);
}

.menu-toggle[aria-expanded="true"] .hamburger::after {
    transform: translateY(-8px) rotate(-45deg);
}

.menu-toggle .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;
}

.menu-toggle[aria-expanded="true"] + .menu {
    display: flex;
    flex-direction: column;
    position: absolute;
    top: 100%;
    left: 0;
    right: 0;
    background-color: var(--color-white);
    box-shadow: var(--shadow-md);
    padding: var(--space-3);
}

.main-navigation a {
    display: block;
    padding: var(--space-2) var(--space-3);
    color: var(--color-gray-700);
    font-weight: 500;
    transition: color var(--transition-fast) ease;
}

.main-navigation a:hover,
.main-navigation a:focus,
.main-navigation a.active {
    color: var(--color-primary-700);
}

/* Page header */
.page-header {
    background-color: var(--color-primary-800);
    color: var(--color-white);
    padding: var(--space-6) 0;
    text-align: center;
}

.page-header h1 {
    color: var(--color-white);
    margin-bottom: 0;
}

/* Hero */
.hero {
    background-color: var(--color-primary-800);
    color: var(--color-white);
    padding: var(--space-7) 0;
    text-align: center;
}

.hero h1 {
    color: var(--color-white);
    font-size: 2.5rem;
    margin-bottom: var(--space-3);
}

.hero p {
    font-size: 1.25rem;
    max-width: 42rem;
    margin-left: auto;
    margin-right: auto;
    margin-bottom: var(--space-5);
    color: var(--color-gray-100);
}

/* Buttons */
.btn {
    display: inline-block;
    font-weight: 500;
    text-align: center;
    white-space: nowrap;
    vertical-align: middle;
    cursor: pointer;
    user-select: none;
    border: 1px solid transparent;
    padding: var(--space-2) var(--space-4);
    font-size: 1rem;
    line-height: 1.5;
    border-radius: var(--radius-md);
    transition: all var(--transition-fast) ease;
}

.btn-primary {
    background-color: var(--color-primary-700);
    color: var(--color-white);
    border-color: var(--color-primary-700);
}

.btn-primary:hover, 
.btn-primary:focus {
    background-color: var(--color-primary-800);
    color: var(--color-white);
    border-color: var(--color-primary-800);
}

.btn-secondary {
    background-color: var(--color-accent-700);
    color: var(--color-white);
    border-color: var(--color-accent-700);
}

.btn-secondary:hover, 
.btn-secondary:focus {
    background-color: var(--color-accent-800);
    color: var(--color-white);
    border-color: var(--color-accent-800);
}

.btn-tertiary {
    background-color: transparent;
    color: var(--color-primary-700);
    border-color: var(--color-primary-700);
}

.btn-tertiary:hover, 
.btn-tertiary:focus {
    background-color: var(--color-primary-50);
    color: var(--color-primary-800);
    border-color: var(--color-primary-800);
}

/* Forms */
.form-group {
    margin-bottom: var(--space-4);
}

label {
    display: block;
    margin-bottom: var(--space-2);
    font-weight: 500;
    color: var(--color-gray-700);
}

.required {
    color: var(--color-highlight-700);
}

input[type="text"],
input[type="email"],
input[type="password"],
input[type="search"],
input[type="tel"],
input[type="url"],
input[type="number"],
select,
textarea {
    display: block;
    width: 100%;
    padding: var(--space-2) var(--space-3);
    font-size: 1rem;
    line-height: 1.5;
    color: var(--color-gray-900);
    background-color: var(--color-white);
    background-clip: padding-box;
    border: 1px solid var(--color-gray-400);
    border-radius: var(--radius-md);
    transition: border-color var(--transition-fast) ease, box-shadow var(--transition-fast) ease;
}

input:focus,
select:focus,
textarea:focus {
    border-color: var(--color-primary-500);
    outline: 0;
    box-shadow: 0 0 0 3px var(--color-primary-100);
}

textarea {
    resize: vertical;
}

.error-message {
    color: var(--color-error);
    font-size: 0.875rem;
    margin-top: var(--space-1);
    display: none;
}

.form-success,
.form-error {
    padding: var(--space-4);
    margin-top: var(--space-4);
    border-radius: var(--radius-md);
    display: none;
}

.form-success {
    background-color: var(--color-accent-100);
    border: 1px solid var(--color-accent-300);
}

.form-error {
    background-color: var(--color-highlight-100);
    border: 1px solid var(--color-highlight-300);
}

/* Footer */
.site-footer {
    background-color: var(--color-primary-900);
    color: var(--color-gray-300);
    padding: var(--space-6) 0;
    margin-top: var(--space-7);
}

.footer-grid {
    display: grid;
    grid-template-columns: 1fr;
    gap: var(--space-5);
    margin-bottom: var(--space-5);
}

.footer-section h4 {
    color: var(--color-white);
    font-size: 1.125rem;
    margin-bottom: var(--space-3);
}

.footer-menu {
    list-style: none;
    padding: 0;
    margin: 0;
}

.footer-menu li {
    margin-bottom: var(--space-2);
}

.footer-menu a {
    color: var(--color-gray-300);
}

.footer-menu a:hover {
    color: var(--color-white);
}

.copyright {
    border-top: 1px solid var(--color-primary-800);
    padding-top: var(--space-4);
    text-align: center;
    font-size: 0.875rem;
    color: var(--color-gray-400);
}

/* Media Queries */
@media (min-width: 768px) {
    .site-header {
        padding: var(--space-4) 0;
    }
    
    .menu-toggle {
        display: none;
    }
    
    .main-navigation ul {
        display: flex;
    }
    
    .main-navigation li {
        margin-bottom: 0;
        margin-left: var(--space-2);
    }
    
    .hero h1 {
        font-size: 3rem;
    }
    
    .footer-grid {
        grid-template-columns: repeat(2, 1fr);
    }
}

@media (min-width: 1024px) {
    html {
        font-size: 20px;
    }
    
    h1 {
        font-size: 2.5rem;
    }
    
    .hero h1 {
        font-size: 3.5rem;
    }
    
    .footer-grid {
        grid-template-columns: repeat(4, 1fr);
    }
}

/* Search Form */
.search-container {
    margin-top: var(--space-5);
    max-width: 800px;
    margin-left: auto;
    margin-right: auto;
}

.search-form {
    background-color: var(--color-white);
    border-radius: var(--radius-lg);
    box-shadow: var(--shadow-xl);
    padding: var(--space-3);
}

.search-group {
    display: flex;
    flex-direction: column;
    gap: var(--space-3);
}

.search-form select {
    flex: 1;
}

.search-form input {
    flex: 3;
}

@media (min-width: 768px) {
    .search-group {
        flex-direction: row;
        align-items: center;
    }
}

/* General section styling */
section {
    padding: var(--space-6) 0;
}

section h2 {
    text-align: center;
    margin-bottom: var(--space-5);
}

/* Grid layouts */
.brands-grid,
.steps,
.posts-grid,
.resources-grid,
.reasons-grid,
.values-grid,
.categories-grid {
    display: grid;
    grid-template-columns: 1fr;
    gap: var(--space-4);
}

@media (min-width: 768px) {
    .brands-grid,
    .posts-grid,
    .resources-grid,
    .reasons-grid,
    .values-grid,
    .categories-grid {
        grid-template-columns: repeat(2, 1fr);
    }
    
    .steps {
        grid-template-columns: repeat(3, 1fr);
    }
}

@media (min-width: 1024px) {
    .brands-grid,
    .resources-grid,
    .reasons-grid,
    .values-grid {
        grid-template-columns: repeat(3, 1fr);
    }
    
    .posts-grid.large {
        grid-template-columns: repeat(3, 1fr);
    }
    
    .posts-grid.small {
        grid-template-columns: repeat(3, 1fr);
    }
}

/* Cards */
.brand-card,
.post-card,
.resource-card,
.reason-card,
.value-card,
.category-card {
    background-color: var(--color-white);
    border-radius: var(--radius-lg);
    box-shadow: var(--shadow-md);
    padding: var(--space-4);
    transition: transform var(--transition-normal) ease, box-shadow var(--transition-normal) ease;
}

.brand-card:hover,
.post-card:hover,
.resource-card:hover,
.reason-card:hover,
.value-card:hover,
.category-card:hover {
    transform: translateY(-4px);
    box-shadow: var(--shadow-lg);
}

.brand-card h3,
.post-card h3,
.resource-card h3,
.reason-card h3,
.value-card h3,
.category-card h3 {
    margin-top: 0;
}

/* Steps */
.step {
    text-align: center;
}

.step-number {
    display: flex;
    align-items: center;
    justify-content: center;
    width: 60px;
    height: 60px;
    background-color: var(--color-primary-700);
    color: var(--color-white);
    border-radius: 50%;
    font-size: 1.5rem;
    font-weight: 700;
    margin: 0 auto var(--space-3);
}

/* Featured resource */
.featured-resource {
    background-color: var(--color-accent-50);
}

.resource-card {
    text-align: center;
    max-width: 800px;
    margin: 0 auto;
}

/* View all button */
.view-all {
    text-align: center;
    margin-top: var(--space-5);
}

/* Animations */
@keyframes fadeIn {
    from { opacity: 0; }
    to { opacity: 1; }
}

@keyframes slideUp {
    from { transform: translateY(20px); opacity: 0; }
    to { transform: translateY(0); opacity: 1; }
}

.fadeIn {
    animation: fadeIn var(--transition-normal) ease forwards;
}

.slideUp {
    animation: slideUp var(--transition-normal) ease forwards;
}

/* Additional utility classes */
.text-center {
    text-align: center;
}

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

.mb-1 {
    margin-bottom: var(--space-1);
}

.mb-2 {
    margin-bottom: var(--space-2);
}

.mb-3 {
    margin-bottom: var(--space-3);
}

.mb-4 {
    margin-bottom: var(--space-4);
}

.mb-5 {
    margin-bottom: var(--space-5);
}

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

.mt-1 {
    margin-top: var(--space-1);
}

.mt-2 {
    margin-top: var(--space-2);
}

.mt-3 {
    margin-top: var(--space-3);
}

.mt-4 {
    margin-top: var(--space-4);
}

.mt-5 {
    margin-top: var(--space-5);
}