/* ============================================================
   ppuzzle.net — Editorial Publication Stylesheet
   Palette: #ffffff, #1a1a1a, #333333, #555555, #dc2626, #3b82f6, #e5e5e5, #f5f5f5
   Fonts: Merriweather (display), Source Sans 3 (body/labels)
   ============================================================ */

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

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

body {
    background: #ffffff;
    font-family: 'Source Sans 3', sans-serif;
    color: #555555;
    line-height: 1.8;
    -webkit-font-smoothing: antialiased;
}

a {
    color: #3b82f6;
    text-decoration: none;
}

a:hover {
    text-decoration: underline;
}

/* --- Masthead / Hero --- */
.masthead {
    background: #ffffff;
    text-align: center;
    padding: 80px 24px 40px;
    border-bottom: 2px solid #1a1a1a;
}

.masthead-inner {
    max-width: 860px;
    margin: 0 auto;
}

.masthead-logo {
    font-family: 'Merriweather', serif;
    font-size: 1rem;
    font-weight: 400;
    color: #555555;
    letter-spacing: 0.25em;
    text-transform: uppercase;
    margin-bottom: 24px;
}

.masthead-headline {
    font-family: 'Merriweather', serif;
    font-size: clamp(1.4rem, 3vw, 2.5rem);
    font-weight: 700;
    color: #1a1a1a;
    line-height: 1.25;
    margin-bottom: 24px;
}

.masthead-rule {
    width: 60px;
    height: 2px;
    background: #1a1a1a;
    margin: 0 auto 16px;
}

.masthead-dateline {
    font-family: 'Source Sans 3', sans-serif;
    font-size: 0.75rem;
    font-weight: 600;
    text-transform: uppercase;
    letter-spacing: 0.1em;
    color: #555555;
    font-variant: small-caps;
}

/* --- Section Navigation --- */
.section-nav {
    background: #f5f5f5;
    border-bottom: 1px solid #e5e5e5;
    position: sticky;
    top: 0;
    z-index: 100;
}

.nav-inner {
    max-width: 1100px;
    margin: 0 auto;
    padding: 0 24px;
    display: flex;
    gap: 0;
    overflow-x: auto;
}

.nav-link {
    font-family: 'Source Sans 3', sans-serif;
    font-size: 0.75rem;
    font-weight: 600;
    text-transform: uppercase;
    letter-spacing: 0.1em;
    color: #555555;
    padding: 14px 20px;
    border-bottom: 2px solid transparent;
    white-space: nowrap;
    transition: color 0.2s, border-color 0.2s;
}

.nav-link:hover {
    color: #1a1a1a;
    text-decoration: none;
    border-bottom-color: #1a1a1a;
}

.nav-link.active {
    color: #1a1a1a;
    border-bottom-color: #3b82f6;
}

/* --- Three-Column Editorial Grid --- */
.editorial-grid {
    display: grid;
    grid-template-columns: 3fr 1fr 1fr;
    gap: 32px;
    max-width: 1100px;
    margin: 0 auto;
    padding: 48px 24px;
}

/* --- Main Feature Column --- */
.main-feature {
    opacity: 0;
    transition: opacity 0.3s ease;
}

.main-feature.visible {
    opacity: 1;
}

.article-label {
    font-family: 'Source Sans 3', sans-serif;
    font-size: 0.75rem;
    font-weight: 600;
    text-transform: uppercase;
    letter-spacing: 0.1em;
    margin-bottom: 12px;
    padding: 4px 0;
    border-top: 2px solid #e5e5e5;
    display: inline-block;
}

.urgent-label {
    color: #dc2626;
    border-top-color: #dc2626;
}

.analysis-label {
    color: #3b82f6;
    border-top-color: #3b82f6;
}

.feature-headline {
    font-family: 'Merriweather', serif;
    font-size: clamp(1.2rem, 2.2vw, 1.75rem);
    font-weight: 700;
    color: #333333;
    line-height: 1.3;
    margin-bottom: 12px;
}

.feature-byline {
    font-family: 'Source Sans 3', sans-serif;
    font-size: 0.75rem;
    font-weight: 600;
    text-transform: uppercase;
    letter-spacing: 0.08em;
    color: #555555;
    margin-bottom: 20px;
    padding-bottom: 16px;
    border-bottom: 1px solid #e5e5e5;
}

.feature-body {
    font-family: 'Source Sans 3', sans-serif;
    font-size: 1rem;
    font-weight: 400;
    color: #555555;
    line-height: 1.8;
    margin-bottom: 16px;
}

.feature-subhead {
    font-family: 'Merriweather', serif;
    font-size: 1rem;
    font-weight: 700;
    color: #333333;
    margin: 28px 0 12px;
}

.read-more-bar {
    margin: 20px 0 0;
    padding-top: 16px;
    border-top: 1px solid #e5e5e5;
}

.read-more-link {
    font-family: 'Source Sans 3', sans-serif;
    font-size: 0.75rem;
    font-weight: 600;
    text-transform: uppercase;
    letter-spacing: 0.1em;
    color: #3b82f6;
}

.read-more-link:hover {
    text-decoration: underline;
}

.secondary-divider {
    height: 1px;
    background: #e5e5e5;
    margin: 40px 0 32px;
}

.secondary-headline {
    font-family: 'Merriweather', serif;
    font-size: clamp(1rem, 1.8vw, 1.4rem);
    font-weight: 700;
    color: #333333;
    line-height: 1.35;
    margin-bottom: 12px;
}

/* --- Sidebar Columns --- */
.sidebar {
    opacity: 0;
    transition: opacity 0.3s ease 0.1s;
}

.sidebar.visible {
    opacity: 1;
}

.sidebar-section-label {
    font-family: 'Source Sans 3', sans-serif;
    font-size: 0.75rem;
    font-weight: 600;
    text-transform: uppercase;
    letter-spacing: 0.1em;
    color: #1a1a1a;
    padding-bottom: 10px;
    border-bottom: 2px solid #1a1a1a;
    margin-bottom: 20px;
}

/* Sidebar Cards */
.sidebar-card {
    border-top: 2px solid #e5e5e5;
    padding: 16px 0;
    margin-bottom: 4px;
}

.sidebar-card.urgent {
    border-top-color: #dc2626;
}

.sidebar-card.analysis {
    border-top-color: #3b82f6;
}

.sidebar-card.archive {
    border-top-color: #e5e5e5;
}

.card-category {
    font-family: 'Source Sans 3', sans-serif;
    font-size: 0.65rem;
    font-weight: 600;
    text-transform: uppercase;
    letter-spacing: 0.12em;
    color: #555555;
    margin-bottom: 6px;
}

.sidebar-card.urgent .card-category {
    color: #dc2626;
}

.sidebar-card.analysis .card-category {
    color: #3b82f6;
}

.card-headline {
    font-family: 'Merriweather', serif;
    font-size: 0.85rem;
    font-weight: 700;
    color: #333333;
    line-height: 1.4;
    margin-bottom: 8px;
}

.card-body {
    font-family: 'Source Sans 3', sans-serif;
    font-size: 0.8rem;
    color: #555555;
    line-height: 1.6;
    margin-bottom: 8px;
}

.card-link {
    font-family: 'Source Sans 3', sans-serif;
    font-size: 0.7rem;
    font-weight: 600;
    text-transform: uppercase;
    letter-spacing: 0.1em;
    color: #3b82f6;
}

.card-link:hover {
    text-decoration: underline;
}

/* Network List */
.network-list {
    list-style: none;
}

.network-list li {
    padding: 6px 0;
    border-bottom: 1px solid #e5e5e5;
    position: relative;
    padding-left: 14px;
}

.network-list li::before {
    content: '';
    position: absolute;
    left: 0;
    top: 50%;
    transform: translateY(-50%);
    width: 4px;
    height: 4px;
    background: #1a1a1a;
}

.network-list li a {
    font-family: 'Source Sans 3', sans-serif;
    font-size: 0.8rem;
    font-weight: 600;
    color: #555555;
    letter-spacing: 0.02em;
}

.network-list li a:hover {
    color: #3b82f6;
    text-decoration: none;
}

/* --- Research Agenda Strip --- */
.strip-section {
    background: #f5f5f5;
    border-top: 1px solid #e5e5e5;
    border-bottom: 1px solid #e5e5e5;
    padding: 32px 24px;
}

.strip-inner {
    max-width: 1100px;
    margin: 0 auto;
}

.strip-label {
    font-family: 'Source Sans 3', sans-serif;
    font-size: 0.75rem;
    font-weight: 600;
    text-transform: uppercase;
    letter-spacing: 0.1em;
    color: #555555;
    margin-bottom: 20px;
}

.strip-items {
    display: grid;
    grid-template-columns: repeat(4, 1fr);
    gap: 24px;
}

.strip-item {
    display: flex;
    align-items: flex-start;
    gap: 12px;
}

.strip-number {
    font-family: 'Merriweather', serif;
    font-size: 1.2rem;
    font-weight: 700;
    color: #e5e5e5;
    line-height: 1;
    flex-shrink: 0;
    margin-top: 2px;
}

.strip-text {
    font-family: 'Source Sans 3', sans-serif;
    font-size: 0.85rem;
    font-weight: 600;
    color: #333333;
    line-height: 1.4;
}

/* --- Footer Network Index --- */
.footer {
    background: #1a1a1a;
    color: #e5e5e5;
    padding: 48px 24px 32px;
}

.footer-inner {
    max-width: 1100px;
    margin: 0 auto;
}

.footer-masthead {
    font-family: 'Merriweather', serif;
    font-size: 1.1rem;
    font-weight: 700;
    color: #ffffff;
    margin-bottom: 6px;
}

.footer-tagline {
    font-family: 'Source Sans 3', sans-serif;
    font-size: 0.75rem;
    font-weight: 400;
    color: #555555;
    text-transform: uppercase;
    letter-spacing: 0.08em;
    margin-bottom: 24px;
}

.footer-rule {
    height: 1px;
    background: #333333;
    margin-bottom: 36px;
}

.footer-columns {
    display: grid;
    grid-template-columns: repeat(4, 1fr);
    gap: 24px;
    margin-bottom: 36px;
}

.footer-col-heading {
    font-family: 'Source Sans 3', sans-serif;
    font-size: 0.7rem;
    font-weight: 600;
    text-transform: uppercase;
    letter-spacing: 0.12em;
    color: #ffffff;
    margin-bottom: 12px;
    padding-bottom: 8px;
    border-bottom: 1px solid #333333;
}

.footer-list {
    list-style: none;
}

.footer-list li {
    position: relative;
    padding-left: 14px;
    margin-bottom: 8px;
}

.footer-list li::before {
    content: '';
    position: absolute;
    left: 0;
    top: 9px;
    width: 4px;
    height: 4px;
    background: #1a1a1a;
    border: 1px solid #555555;
}

.footer-list li a {
    font-family: 'Source Sans 3', sans-serif;
    font-size: 0.8rem;
    color: #e5e5e5;
    transition: color 0.2s;
}

.footer-list li a:hover {
    color: #3b82f6;
    text-decoration: none;
}

.footer-bottom {
    border-top: 1px solid #333333;
    padding-top: 20px;
    display: flex;
    align-items: center;
    gap: 12px;
    flex-wrap: wrap;
}

.footer-copy {
    font-family: 'Source Sans 3', sans-serif;
    font-size: 0.75rem;
    color: #555555;
}

.footer-sep {
    color: #333333;
    font-size: 0.75rem;
}

.footer-legal {
    font-family: 'Source Sans 3', sans-serif;
    font-size: 0.75rem;
    color: #555555;
    transition: color 0.2s;
}

.footer-legal:hover {
    color: #e5e5e5;
    text-decoration: none;
}

/* --- Responsive: Mobile --- */
@media (max-width: 768px) {
    .masthead {
        padding: 48px 20px 32px;
    }

    .editorial-grid {
        grid-template-columns: 1fr;
        gap: 24px;
        padding: 32px 20px;
    }

    .sidebar-left {
        order: 2;
    }

    .sidebar-right {
        order: 3;
    }

    .strip-items {
        grid-template-columns: 1fr 1fr;
        gap: 16px;
    }

    .footer-columns {
        grid-template-columns: 1fr 1fr;
        gap: 20px;
    }

    .nav-inner {
        padding: 0 12px;
    }

    .nav-link {
        padding: 12px 14px;
    }
}

@media (max-width: 480px) {
    .strip-items {
        grid-template-columns: 1fr;
    }

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