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

body {
    font-family: var(--font-body);
    background-color: var(--color-bg-page);
    color: var(--color-text-primary);
    line-height: var(--line-height-body);
}

.container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 20px;
}

/* ===== HEADER & NAVIGATION ===== */
.main-header {
    background-color: var(--color-bg-surface);
    border-bottom: 1px solid var(--color-border);
    padding: 1.1rem 0;
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    z-index: 300;
    transition: transform var(--transition-base), box-shadow var(--transition-base);
}

.main-header.scrolled {
    box-shadow: 0 2px 10px rgba(0, 0, 0, 0.4);
}

.main-header.header-hidden {
    transform: translateY(-100%);
}

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

/* ===== HAMBURGER BUTTON ===== */
.nav-toggle {
    display: none;
    background: none;
    border: none;
    cursor: pointer;
    padding: 0.4rem;
    flex-direction: column;
    gap: 5px;
    flex-shrink: 0;
}

.nav-toggle span {
    display: block;
    width: 24px;
    height: 2px;
    background: var(--color-text-primary);
    border-radius: 2px;
    transition: transform var(--transition-base), opacity var(--transition-base);
}

/* Animate to X when open */
.nav-toggle.open span:nth-child(1) { transform: translateY(7px) rotate(45deg); }
.nav-toggle.open span:nth-child(2) { opacity: 0; transform: scaleX(0); }
.nav-toggle.open span:nth-child(3) { transform: translateY(-7px) rotate(-45deg); }

.logo a {
    text-decoration: none;
    color: inherit;
}

.logo h1 {
    font: 700 var(--font-logo-size)/1 var(--font-heading);
    letter-spacing: 2px;
}

.logo .accent {
    font-weight: 300;
    color: var(--color-text-secondary);
}

.main-nav ul {
    display: flex;
    list-style: none;
    gap: 2rem;
}

.nav-link {
    color: var(--color-text-primary);
    text-decoration: none;
    font-weight: 500;
    transition: color var(--transition-base);
}

.nav-link:hover { color: var(--color-text-secondary); }
.nav-link.active { color: var(--color-accent); }

/* ===== MAIN LAYOUT ===== */
.main-content {
    min-height: calc(100vh - 200px);
    padding: 2rem 0;
}

.main-footer {
    background-color: var(--color-bg-surface);
    border-top: 1px solid var(--color-border);
    padding: 1.5rem 0;
    margin-top: 3rem;
}

.main-footer p {
    text-align: center;
    color: var(--color-text-muted);
    font-size: var(--font-size-footer);
}

/* ===== CHART SUBTITLE ===== */
.chart-subtitle {
    color: var(--color-text-muted);
    font-size: var(--font-size-sm);
    margin: -0.5rem 0 1rem;
}

/* ===== CHART EXPAND / DOWNLOAD ROW ===== */
.chart-expand-row {
    display: flex;
    justify-content: center;
    align-items: center;
    gap: 0.75rem;
    margin-top: 0.75rem;
    position: relative;
}

.chart-expand-btn {
    background: none;
    border: 1px solid var(--color-border-control);
    border-radius: var(--radius-sm);
    color: var(--color-text-secondary);
    font-size: var(--font-size-sm);
    padding: 0.35rem 1.1rem;
    cursor: pointer;
    transition: border-color var(--transition-fast), color var(--transition-fast);
}

.chart-expand-btn:hover {
    border-color: var(--color-accent);
    color: var(--color-accent);
}

.chart-download-btn {
    position: absolute;
    right: 0;
    background: none;
    border: 1px solid var(--color-border-control);
    border-radius: var(--radius-sm);
    color: var(--color-text-muted);
    font-size: var(--font-size-xs);
    padding: 0.35rem 0.8rem;
    text-decoration: none;
    cursor: pointer;
    transition: border-color var(--transition-fast), color var(--transition-fast);
}

.chart-download-btn:hover {
    border-color: var(--color-accent);
    color: var(--color-accent);
}

/* ===== PAGE HEADERS ===== */
.visualization-section {
    text-align: center;
    margin-bottom: 2rem;
    max-width: 1035px;
    margin-left: auto;
    margin-right: auto;
}

.page-header {
    text-align: center;
    margin-bottom: 2rem;
    max-width: 900px;
    margin-left: auto;
    margin-right: auto;
}

.viz-header h2,
.page-header h2 {
    font: var(--font-heading-weight) var(--font-heading-size-xl)/1.2 var(--font-heading);
    margin-bottom: 1rem;
}

.viz-header p,
.page-header p {
    font-size: var(--font-size-lg);
    color: var(--color-text-secondary);
    max-width: 800px;
    margin: 0 auto;
}

/* ===== RESPONSIVE BASE ===== */
@media (max-width: 768px) {
    .viz-header h2, .page-header h2 { font-size: 2rem; }

    /* Show hamburger, hide inline nav */
    .nav-toggle { display: flex; }

    .main-nav {
        display: none;
        position: absolute;
        top: 100%;
        left: 0;
        right: 0;
        background: var(--color-bg-surface);
        border-bottom: 1px solid var(--color-border);
        z-index: 200;
    }

    .main-nav.open { display: block; }

    .main-nav ul {
        flex-direction: column;
        gap: 0;
        padding: 0.5rem 0;
    }

    .main-nav ul li { width: 100%; }

    .nav-link {
        display: block;
        padding: 0.75rem 1.5rem;
    }
}

/* ===== DIRECTORY GRID STYLES ===== */
.directory-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(400px, 1fr));
    gap: 2rem;
    margin: 2rem 0;
}

.directory-group {
    background: var(--color-bg-surface);
    border: 1px solid var(--color-border);
    border-radius: var(--radius-md);
    padding: 1.5rem;
}

.directory-group h3 {
    margin: 0 0 1rem 0;
    font-size: var(--font-heading-size-sm);
    color: var(--color-directory-group-heading);
}

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

.asset-list li {
    margin: 0.5rem 0;
}

.asset-link {
    color: var(--color-text-primary);
    text-decoration: none;
    padding: 0.25rem 0;
    display: block;
    transition: color var(--transition-base);
    cursor: pointer;
}

.asset-link:hover {
    color: var(--color-accent);
}

/* Responsive adjustment for smaller screens */
@media (max-width: 768px) {
    .directory-grid {
        grid-template-columns: 1fr;
        gap: 1rem;
    }
}

/* ===== ABOUT PAGE STYLES ===== */
.about-content {
    max-width: 800px;
    margin: 0 auto;
    padding: 2rem 0;
}

.about-section {
    background: var(--color-bg-surface);
    border: 1px solid var(--color-border);
    border-radius: var(--radius-lg);
    padding: 2.5rem;
    margin-bottom: 2rem;
}

.about-section h3 {
    color: var(--color-accent);
    font-size: var(--font-heading-size-lg);
    margin-bottom: 1.2rem;
    border-bottom: 1px solid var(--color-border);
    padding-bottom: 0.5rem;
}

.about-section p {
    margin-bottom: 1.5rem;
    font-size: var(--font-size-md);
    line-height: var(--line-height-relaxed);
    color: var(--color-text-secondary);
}

.about-section ul {
    margin: 1.5rem 0;
    padding-left: 1.5rem;
}

.about-section li {
    margin-bottom: 0.8rem;
    color: var(--color-text-primary);
}

.about-section a {
    color: var(--color-accent);
    text-decoration: none;
    font-weight: 500;
}

.about-section a:hover {
    text-decoration: underline;
}

/* Featured Quote or Mission Highlight */
.mission-highlight {
    font-style: italic;
    font-size: var(--font-size-xl);
    color: var(--color-text-primary);
    border-left: 4px solid var(--color-accent);
    padding-left: 1.5rem;
    margin: 2rem 0;
}

/* Responsive adjustment */
@media (max-width: 768px) {
    .about-section {
        padding: 1.5rem;
    }
}