/* ============================================================
   rational.business — Executive Briefing Style
   Colors: #ffffff, #f9fafb, #111827, #374151, #6b7280, #d1d5db, #e5e7eb, #1e3a5f
   Fonts: Inter (display/body), Source Code Pro (data/ref)
   ============================================================ */

*, *::before, *::after {
    box-sizing: border-box;
    margin: 0;
    padding: 0;
}

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

body {
    background: #ffffff;
    color: #374151;
    font-family: 'Inter', sans-serif;
    font-size: 0.9rem;
    line-height: 1.7;
    min-height: 100vh;
}

/* ── Navy Authority Bar ── */
#authority-bar {
    width: 100%;
    height: 4px;
    background: #1e3a5f;
    position: fixed;
    top: 0;
    left: 0;
    z-index: 100;
}

/* ── Briefing Header / Hero ── */
#briefing-header {
    padding: 48px 8% 24px;
    margin-top: 4px;
    background: #ffffff;
}

.header-inner {
    display: flex;
    justify-content: space-between;
    align-items: flex-start;
    max-width: 1100px;
    margin: 0 auto;
    gap: 32px;
}

.header-left {
    flex: 1;
}

#site-name {
    font-size: clamp(1.3rem, 3vw, 2.2rem);
    font-weight: 600;
    color: #111827;
    letter-spacing: -0.02em;
    line-height: 1.2;
    margin-bottom: 8px;
}

.header-descriptor {
    font-size: 1rem;
    font-weight: 500;
    color: #374151;
    margin-bottom: 4px;
}

.header-sub {
    font-size: 0.85rem;
    color: #6b7280;
    font-weight: 400;
}

.header-meta {
    display: flex;
    flex-direction: column;
    align-items: flex-end;
    gap: 8px;
    flex-shrink: 0;
}

.header-tag {
    font-family: 'Source Code Pro', monospace;
    font-size: 0.7rem;
    font-weight: 500;
    color: #ffffff;
    background: #1e3a5f;
    padding: 4px 10px;
    letter-spacing: 0.1em;
}

.header-date {
    font-family: 'Source Code Pro', monospace;
    font-size: 0.75rem;
    color: #6b7280;
}

.header-rule {
    max-width: 1100px;
    margin: 24px auto 0;
    border: none;
    border-top: 1px solid #d1d5db;
}

/* ── Insight Banner ── */
#insight-banner {
    background: #1e3a5f;
    padding: 20px 8%;
    margin-top: 0;
}

.banner-inner {
    max-width: 1100px;
    margin: 0 auto;
    display: flex;
    align-items: baseline;
    gap: 20px;
}

.banner-label {
    font-family: 'Source Code Pro', monospace;
    font-size: 0.65rem;
    font-weight: 500;
    color: #d1d5db;
    letter-spacing: 0.12em;
    white-space: nowrap;
    flex-shrink: 0;
}

.banner-text {
    font-size: 0.9rem;
    color: #ffffff;
    line-height: 1.6;
    font-weight: 400;
}

/* ── 2x2 Panel Grid ── */
#panel-grid-section {
    padding: 40px 8%;
}

#panel-grid {
    display: grid;
    grid-template-columns: 1fr 1fr;
    border: 1px solid #e5e7eb;
    max-width: 1000px;
    margin: 0 auto;
}

.panel {
    border: 1px solid #e5e7eb;
    padding: 28px 28px 20px;
    display: flex;
    flex-direction: column;
    background: #ffffff;
    transition: background 0.2s ease;
    position: relative;
}

.panel:hover {
    background: #f9fafb;
}

.panel-header {
    display: flex;
    align-items: baseline;
    gap: 12px;
    margin-bottom: 16px;
    padding-bottom: 12px;
    border-bottom: 1px solid #e5e7eb;
}

.panel-num {
    font-family: 'Source Code Pro', monospace;
    font-size: 0.7rem;
    color: #6b7280;
    font-weight: 500;
    letter-spacing: 0.05em;
}

.panel-title {
    font-size: 0.85rem;
    font-weight: 600;
    color: #111827;
    letter-spacing: 0.02em;
    text-transform: uppercase;
}

.panel-body {
    flex: 1;
}

.panel-list {
    list-style: none;
    padding: 0;
    counter-reset: panel-counter;
}

.panel-list li {
    counter-increment: panel-counter;
    display: flex;
    align-items: flex-start;
    gap: 10px;
    padding: 6px 0;
    border-bottom: 1px solid #f3f4f6;
    font-size: 0.87rem;
    color: #374151;
    line-height: 1.5;
}

.panel-list li::before {
    content: counter(panel-counter, decimal-leading-zero);
    font-family: 'Source Code Pro', monospace;
    font-size: 0.7rem;
    color: #1e3a5f;
    font-weight: 500;
    flex-shrink: 0;
    margin-top: 2px;
    min-width: 22px;
}

.panel-list li:last-child {
    border-bottom: none;
}

.panel-footer {
    margin-top: 16px;
    padding-top: 10px;
    border-top: 1px solid #f3f4f6;
}

.doc-ref {
    font-family: 'Source Code Pro', monospace;
    font-size: 0.65rem;
    color: #6b7280;
    letter-spacing: 0.08em;
}

/* ── Metric Grid (Panel 3) ── */
.metric-grid {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 16px;
    padding: 4px 0;
}

.metric-item {
    display: flex;
    flex-direction: column;
    align-items: flex-start;
    padding: 12px;
    background: #f9fafb;
    border: 1px solid #e5e7eb;
}

.metric-value {
    font-size: 2rem;
    font-weight: 700;
    color: #1e3a5f;
    line-height: 1;
    font-family: 'Inter', sans-serif;
}

.metric-unit {
    font-size: 1rem;
    font-weight: 600;
    color: #1e3a5f;
    margin-left: 1px;
    line-height: 1;
    vertical-align: super;
}

.metric-label {
    font-size: 0.75rem;
    color: #6b7280;
    margin-top: 6px;
    line-height: 1.4;
}

/* ── Methodology Section ── */
#methodology-section {
    background: #f9fafb;
    border-top: 1px solid #e5e7eb;
    border-bottom: 1px solid #e5e7eb;
    padding: 40px 8%;
}

.methodology-inner {
    max-width: 1000px;
    margin: 0 auto;
}

.methodology-label {
    font-family: 'Source Code Pro', monospace;
    font-size: 0.65rem;
    color: #6b7280;
    letter-spacing: 0.15em;
    margin-bottom: 24px;
    font-weight: 500;
}

.methodology-content {
    display: flex;
    align-items: stretch;
    gap: 0;
}

.method-step {
    flex: 1;
    display: flex;
    flex-direction: column;
    align-items: flex-start;
    padding: 0 24px;
    opacity: 0;
    transform: translateY(12px);
    transition: opacity 0.4s ease, transform 0.4s ease;
}

.method-step.visible {
    opacity: 1;
    transform: translateY(0);
}

.method-step:first-child {
    padding-left: 0;
}

.method-divider {
    width: 1px;
    background: #d1d5db;
    flex-shrink: 0;
    align-self: stretch;
    min-height: 80px;
}

.method-num {
    font-family: 'Source Code Pro', monospace;
    font-size: 0.7rem;
    color: #1e3a5f;
    font-weight: 500;
    letter-spacing: 0.08em;
    margin-bottom: 8px;
}

.method-text strong {
    display: block;
    font-size: 0.9rem;
    font-weight: 600;
    color: #111827;
    margin-bottom: 4px;
}

.method-text span {
    font-size: 0.82rem;
    color: #6b7280;
    line-height: 1.5;
}

/* ── Document Reference Footer ── */
#doc-footer {
    background: #f9fafb;
    border-top: 1px solid #e5e7eb;
    padding: 24px 8% 0;
}

.footer-inner {
    max-width: 1100px;
    margin: 0 auto;
    display: flex;
    justify-content: space-between;
    align-items: flex-start;
    gap: 24px;
    padding-bottom: 20px;
}

.footer-left {
    display: flex;
    flex-direction: column;
    gap: 4px;
}

.footer-brand {
    font-size: 0.85rem;
    font-weight: 600;
    color: #111827;
}

.footer-desc {
    font-size: 0.78rem;
    color: #6b7280;
}

.footer-meta {
    display: flex;
    gap: 20px;
    align-items: center;
    flex-wrap: wrap;
    justify-content: flex-end;
}

.doc-meta {
    font-family: 'Source Code Pro', monospace;
    font-size: 0.7rem;
    color: #6b7280;
    letter-spacing: 0.05em;
}

.footer-bar {
    height: 4px;
    background: #1e3a5f;
    margin: 0 -8%;
}

/* ── Responsive ── */
@media (max-width: 768px) {
    #briefing-header {
        padding: 44px 5% 20px;
    }

    .header-inner {
        flex-direction: column;
        gap: 16px;
    }

    .header-meta {
        align-items: flex-start;
    }

    #insight-banner {
        padding: 16px 5%;
    }

    .banner-inner {
        flex-direction: column;
        gap: 8px;
    }

    #panel-grid-section {
        padding: 24px 5%;
    }

    #panel-grid {
        grid-template-columns: 1fr;
    }

    #methodology-section {
        padding: 32px 5%;
    }

    .methodology-content {
        flex-direction: column;
        gap: 20px;
    }

    .method-divider {
        width: 100%;
        height: 1px;
        min-height: unset;
    }

    .method-step {
        padding: 0;
    }

    #doc-footer {
        padding: 20px 5% 0;
    }

    .footer-inner {
        flex-direction: column;
        gap: 16px;
    }

    .footer-meta {
        justify-content: flex-start;
    }

    .footer-bar {
        margin: 0 -5%;
    }

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

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