/* Main CSS - Core Layout and Structure */

/* ===== CSS Variables ===== */
:root {
    /* Colors - Academic Palette */
    --color-primary: #1e3a5f;
    --color-secondary: #8b7355;
    --color-accent: #6b2c3e;
    --color-background: #fafaf8;
    --color-text: #2d2d2d;
    --color-text-light: #5a5a5a;
    --color-border: #d4d4d0;
    --color-card-bg: #ffffff;
    --color-hover: #f0f0ed;
    
    /* Typography */
    --font-serif: Georgia, 'Times New Roman', serif;
    --font-sans: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
    
    /* Spacing */
    --spacing-xs: 0.5rem;
    --spacing-sm: 1rem;
    --spacing-md: 1.5rem;
    --spacing-lg: 2rem;
    --spacing-xl: 3rem;
    
    /* Layout */
    --max-content-width: 75ch;
    --sidebar-width: 280px;
    --header-height: 80px;
    
    /* Shadows */
    --shadow-sm: 0 1px 3px rgba(0, 0, 0, 0.1);
    --shadow-md: 0 4px 6px rgba(0, 0, 0, 0.1);
    --shadow-lg: 0 10px 20px rgba(0, 0, 0, 0.1);
    
    /* Transitions */
    --transition-fast: 0.2s ease;
    --transition-medium: 0.3s ease;
}

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

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

body {
    font-family: var(--font-serif);
    font-size: 1.125rem;
    line-height: 1.8;
    color: var(--color-text);
    background-color: var(--color-background);
    -webkit-font-smoothing: antialiased;
    -moz-osx-font-smoothing: grayscale;
}

/* ===== Typography ===== */
h1, h2, h3, h4, h5, h6 {
    font-family: var(--font-sans);
    font-weight: 600;
    line-height: 1.3;
    color: var(--color-primary);
    margin-bottom: var(--spacing-md);
}

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

h2 {
    font-size: 2rem;
    margin-top: var(--spacing-xl);
}

h3 {
    font-size: 1.5rem;
    margin-top: var(--spacing-lg);
}

h4 {
    font-size: 1.25rem;
}

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

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

a:hover {
    color: var(--color-accent);
    text-decoration: underline;
}

/* ===== Header ===== */
header {
    background-color: var(--color-card-bg);
    border-bottom: 2px solid var(--color-primary);
    box-shadow: var(--shadow-md);
    position: sticky;
    top: 0;
    z-index: 1000;
}

.header-container {
    max-width: 1400px;
    margin: 0 auto;
    padding: var(--spacing-md) var(--spacing-lg);
    display: flex;
    justify-content: space-between;
    align-items: center;
    flex-wrap: wrap;
}

.logo-section {
    flex: 0 0 auto;
}

.site-title {
    font-size: 1.75rem;
    margin: 0;
    color: var(--color-primary);
}

.site-subtitle {
    font-size: 0.875rem;
    color: var(--color-text-light);
    font-family: var(--font-sans);
    margin: 0;
}

/* ===== Navigation ===== */
.main-nav {
    flex: 1 1 auto;
    display: flex;
    justify-content: flex-end;
}

.nav-toggle {
    display: none;
    background: none;
    border: none;
    cursor: pointer;
    padding: var(--spacing-xs);
}

.nav-toggle span {
    display: block;
    width: 25px;
    height: 3px;
    background-color: var(--color-primary);
    margin: 5px 0;
    transition: var(--transition-fast);
}

.nav-menu {
    display: flex;
    list-style: none;
    gap: var(--spacing-xs);
}

.nav-menu li {
    margin: 0;
}

.nav-menu a {
    display: block;
    padding: var(--spacing-xs) var(--spacing-md);
    font-family: var(--font-sans);
    font-size: 0.95rem;
    color: var(--color-text);
    text-decoration: none;
    border-radius: 4px;
    transition: var(--transition-fast);
}

.nav-menu a:hover,
.nav-menu a.active {
    background-color: var(--color-primary);
    color: white;
    text-decoration: none;
}

/* ===== Main Content Areas ===== */
.home-container {
    max-width: 1200px;
    margin: 0 auto;
}

.content-wrapper {
    max-width: 900px;
    margin: 0 auto;
    padding: var(--spacing-xl) var(--spacing-lg);
}

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

.hero-content h1,
.hero-content h2 {
    color: white;
    margin-bottom: var(--spacing-md);
}

.hero-content h1 {
    font-size: 3rem;
}

.hero-content h2 {
    font-size: 1.75rem;
    font-weight: 400;
    margin-top: 0;
}

.lead-text {
    font-size: 1.25rem;
    line-height: 1.6;
    max-width: 800px;
    margin: var(--spacing-lg) auto 0;
}

/* ===== Sections ===== */
.overview-section,
.phases-section,
.navigation-section {
    padding: var(--spacing-xl) var(--spacing-lg);
}

.overview-section {
    background-color: var(--color-card-bg);
}

.section-intro {
    font-size: 1.1rem;
    color: var(--color-text-light);
    margin-bottom: var(--spacing-xl);
}

/* ===== Phase Grid ===== */
.phase-grid {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(300px, 1fr));
    gap: var(--spacing-lg);
    margin-top: var(--spacing-xl);
}

.phase-card {
    background-color: var(--color-card-bg);
    border: 1px solid var(--color-border);
    border-radius: 8px;
    padding: var(--spacing-lg);
    box-shadow: var(--shadow-sm);
    transition: transform var(--transition-medium), box-shadow var(--transition-medium);
}

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

.phase-number {
    display: inline-block;
    width: 50px;
    height: 50px;
    line-height: 50px;
    text-align: center;
    background-color: var(--color-primary);
    color: white;
    font-family: var(--font-sans);
    font-size: 1.5rem;
    font-weight: bold;
    border-radius: 50%;
    margin-bottom: var(--spacing-md);
}

.phase-card h3 {
    font-size: 1.25rem;
    margin-top: var(--spacing-sm);
    margin-bottom: var(--spacing-sm);
}

.phase-card p {
    font-size: 1rem;
    line-height: 1.6;
    color: var(--color-text-light);
}

.phase-link {
    display: inline-block;
    margin-top: var(--spacing-md);
    padding: var(--spacing-xs) var(--spacing-md);
    background-color: var(--color-primary);
    color: white;
    border-radius: 4px;
    font-family: var(--font-sans);
    font-size: 0.95rem;
    transition: background-color var(--transition-fast);
}

.phase-link:hover {
    background-color: var(--color-accent);
    text-decoration: none;
}

/* ===== Navigation Guide ===== */
.navigation-guide {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
    gap: var(--spacing-lg);
    margin-top: var(--spacing-lg);
}

.guide-item {
    padding: var(--spacing-lg);
    background-color: var(--color-card-bg);
    border-left: 4px solid var(--color-secondary);
    border-radius: 4px;
}

.guide-item h4 {
    font-size: 1.1rem;
    color: var(--color-primary);
    margin-bottom: var(--spacing-sm);
}

.guide-item p {
    font-size: 0.95rem;
    margin-bottom: 0;
}

/* ===== Footer ===== */
footer {
    background-color: var(--color-primary);
    color: white;
    padding: var(--spacing-lg);
    text-align: center;
    margin-top: var(--spacing-xl);
}

.footer-container {
    max-width: 1200px;
    margin: 0 auto;
}

footer p {
    margin-bottom: var(--spacing-xs);
    font-family: var(--font-sans);
    font-size: 0.9rem;
}

.footer-note {
    font-size: 0.85rem;
    opacity: 0.8;
}

.footer-contact {
    font-size: 0.85rem;
    margin-top: var(--spacing-xs);
}

.footer-contact a {
    color: white;
    text-decoration: none;
    border-bottom: 1px solid rgba(255, 255, 255, 0.5);
    transition: border-color 0.2s ease;
}

.footer-contact a:hover {
    border-bottom-color: white;
}

/* ===== Responsive Design ===== */
@media (max-width: 1024px) {
    .header-container {
        padding: var(--spacing-sm) var(--spacing-md);
    }
    
    .content-wrapper {
        padding: var(--spacing-lg) var(--spacing-md);
    }
}

@media (max-width: 768px) {
    html {
        font-size: 15px;
    }
    
    .nav-toggle {
        display: block;
    }
    
    .nav-menu {
        display: none;
        position: absolute;
        top: 100%;
        left: 0;
        right: 0;
        background-color: var(--color-card-bg);
        flex-direction: column;
        box-shadow: var(--shadow-md);
        padding: var(--spacing-sm);
    }
    
    .nav-menu.active {
        display: flex;
    }
    
    .nav-menu a {
        padding: var(--spacing-md);
    }
    
    .hero-content h1 {
        font-size: 2rem;
    }
    
    .hero-content h2 {
        font-size: 1.25rem;
    }
    
    .phase-grid {
        grid-template-columns: 1fr;
    }
}

@media (max-width: 480px) {
    html {
        font-size: 14px;
    }
    
    .header-container {
        padding: var(--spacing-sm);
    }
    
    .content-wrapper,
    .hero-section,
    .overview-section,
    .phases-section,
    .navigation-section {
        padding: var(--spacing-md) var(--spacing-sm);
    }
}