:root {
    --bg: #e8ece7;
    --bg-deep: #dce4de;
    --panel: #f9fbf8;
    --panel-strong: #eef3ee;
    --ink: #1d2b2a;
    --muted: #536565;
    --line: #c8d2cb;
    --accent: #1f5a52;
    --accent-strong: #143f3a;
    --warning: #805a16;
    --warning-bg: #faf3de;
    --alert: #7d2b22;
    --alert-bg: #fae8e5;
    --shadow: 0 14px 34px rgba(18, 43, 39, 0.08);
    --app-height: 100vh;
}

* {
    box-sizing: border-box;
}

html {
    scroll-behavior: smooth;
}

body {
    margin: 0;
    color: var(--ink);
    font-family: "Avenir Next", "Segoe UI", sans-serif;
    background:
        linear-gradient(180deg, rgba(31, 90, 82, 0.07), transparent 18%),
        linear-gradient(180deg, var(--bg) 0%, var(--bg-deep) 100%);
}

body.has-overlay {
    overflow: hidden;
    overscroll-behavior: none;
}

a {
    color: var(--accent-strong);
}

.site-shell {
    display: grid;
    grid-template-columns: 300px 1fr;
    min-height: 100vh;
}

.sidebar {
    padding: 2rem 1.5rem;
    border-right: 1px solid var(--line);
    background: rgba(248, 251, 248, 0.92);
    position: sticky;
    top: 0;
    height: 100vh;
    overflow-y: auto;
}

.brand {
    display: inline-block;
    font-size: 1.55rem;
    font-weight: 700;
    text-decoration: none;
    line-height: 1.1;
}

.brand-subtitle {
    margin: 0.7rem 0 0;
    color: var(--ink);
    font-size: 0.95rem;
    line-height: 1.4;
}

.site-status-badge {
    display: inline-flex;
    flex-wrap: wrap;
    gap: 0.45rem;
    margin-top: 0.9rem;
    margin-bottom: 0.4rem;
}

.site-status-badge span {
    display: inline-flex;
    align-items: center;
    padding: 0.3rem 0.6rem;
    border-radius: 999px;
    border: 1px solid rgba(31, 90, 82, 0.16);
    background: rgba(31, 90, 82, 0.08);
    color: var(--accent-strong);
    font-size: 0.78rem;
    font-weight: 700;
    letter-spacing: 0.04em;
}

.brand-copy,
.sidebar-nav a,
.sidebar-list a,
.panel-heading p,
.topic-card p,
.reference-card p,
dd,
.lede,
.topic-subcategory,
.timestamp {
    color: var(--muted);
}

.sidebar-nav {
    display: flex;
    flex-direction: column;
    gap: 0.55rem;
    margin: 1.5rem 0;
}

.sidebar-nav a,
.sidebar-list a {
    text-decoration: none;
}

.feedback-link {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    padding: 0.75rem 0.95rem;
    border-radius: 12px;
    border: 1px solid rgba(20, 63, 58, 0.16);
    background: rgba(31, 90, 82, 0.08);
    color: var(--accent-strong);
    font-weight: 700;
    transition: background-color 140ms ease, border-color 140ms ease, transform 140ms ease;
}

.feedback-link:hover,
.feedback-link:focus-visible {
    background: rgba(31, 90, 82, 0.12);
    border-color: rgba(20, 63, 58, 0.24);
    transform: translateY(-1px);
    outline: none;
}

.sidebar-section {
    margin-top: 1.5rem;
}

.sidebar-section h2,
.panel h2,
.info-card h2,
.reference-card h2,
.guidance-banner h2 {
    margin: 0 0 0.8rem;
    font-size: 1rem;
    letter-spacing: 0.01em;
}

.sidebar-list {
    list-style: none;
    padding: 0;
    margin: 0;
    display: grid;
    gap: 0.7rem;
}

.content {
    padding: 2rem;
}

.site-footer {
    margin-top: 2rem;
    padding: 1.2rem 0 0.2rem;
    border-top: 1px solid var(--line);
    color: var(--muted);
    display: grid;
    gap: 0.35rem;
    font-size: 0.92rem;
}

.site-footer p {
    margin: 0;
}

.footer-note {
    max-width: 52ch;
}

.footer-links {
    display: flex;
    flex-wrap: wrap;
    gap: 0.9rem;
}

.footer-links a {
    text-decoration: none;
}

.breadcrumbs {
    display: flex;
    flex-wrap: wrap;
    gap: 0.55rem;
    margin-bottom: 1rem;
    font-size: 0.9rem;
    color: var(--muted);
}

.breadcrumbs > * + *::before {
    content: "/";
    margin-right: 0.55rem;
    color: rgba(83, 101, 101, 0.65);
}

.breadcrumbs a {
    color: var(--accent-strong);
    text-decoration: none;
}

.breadcrumbs span {
    color: var(--muted);
}

.sticky-context-bar {
    position: sticky;
    top: 0.75rem;
    z-index: 20;
    display: grid;
    gap: 0.15rem;
    margin-bottom: 1rem;
    padding: 0.8rem 1rem;
    border: 1px solid rgba(20, 63, 58, 0.14);
    border-radius: 16px;
    background: rgba(249, 251, 248, 0.94);
    box-shadow: 0 10px 24px rgba(18, 43, 39, 0.08);
    backdrop-filter: blur(10px);
}

.sticky-context-meta {
    display: flex;
    flex-wrap: wrap;
    gap: 0.4rem;
    align-items: center;
    font-size: 0.8rem;
    color: var(--muted);
    text-transform: uppercase;
    letter-spacing: 0.08em;
    font-weight: 700;
}

.sticky-context-kicker {
    color: var(--accent);
}

.sticky-context-divider {
    color: rgba(83, 101, 101, 0.65);
}

.sticky-context-bar h2 {
    margin: 0;
    font-size: clamp(1rem, 2.2vw, 1.25rem);
    line-height: 1.1;
}

.hero,
.panel,
.topic-header,
.guidance-banner {
    background: var(--panel);
    border: 1px solid rgba(20, 63, 58, 0.1);
    border-radius: 18px;
    box-shadow: var(--shadow);
}

.hero {
    padding: 2rem;
    display: grid;
    gap: 1.4rem;
    margin-bottom: 1.3rem;
}

.beta-notice {
    margin-bottom: 1.3rem;
    padding: 0.95rem 1rem;
    border-radius: 14px;
    border: 1px solid rgba(20, 63, 58, 0.12);
    background: rgba(249, 251, 248, 0.78);
    color: var(--muted);
}

.beta-notice p {
    margin: 0;
}

.active-filter-banner {
    margin-bottom: 1.3rem;
    padding: 1rem 1.1rem;
    border-radius: 16px;
    border: 1px solid rgba(20, 63, 58, 0.14);
    background: rgba(249, 251, 248, 0.92);
    box-shadow: var(--shadow);
    display: flex;
    flex-wrap: wrap;
    justify-content: space-between;
    gap: 1rem;
    align-items: center;
}

.active-filter-banner h2,
.active-filter-banner p {
    margin: 0;
}

.hero h1,
.panel h1,
.topic-header h1 {
    margin: 0.2rem 0 0.6rem;
    font-size: clamp(2rem, 4vw, 3rem);
    line-height: 1.04;
}

.hero-copy {
    max-width: 68ch;
    font-size: 1.02rem;
}

.hero-subtitle {
    margin: 0 0 0.9rem;
    max-width: 50ch;
    color: var(--accent-strong);
    font-size: 1.08rem;
    line-height: 1.35;
    font-weight: 600;
}

.eyebrow,
.topic-category,
dt,
.reference-org,
.inline-link-card span {
    text-transform: uppercase;
    letter-spacing: 0.08em;
    font-size: 0.73rem;
    font-weight: 700;
    color: var(--accent);
}

.search-form {
    padding: 1rem;
    background: var(--panel-strong);
    border-radius: 14px;
}

.search-form label {
    display: block;
    margin-bottom: 0.45rem;
    font-weight: 600;
}

.search-row,
.filter-row {
    display: flex;
    gap: 0.75rem;
    align-items: center;
}

.filter-row {
    margin-top: 0.75rem;
}

input[type="search"],
select,
textarea {
    width: 100%;
    padding: 0.95rem 1rem;
    border: 1px solid var(--line);
    border-radius: 12px;
    background: #fff;
    font: inherit;
    color: var(--ink);
}

textarea {
    resize: vertical;
}

button {
    border: 0;
    border-radius: 12px;
    padding: 0.95rem 1.15rem;
    background: var(--accent-strong);
    color: white;
    cursor: pointer;
    font: inherit;
    font-weight: 600;
}

.panel {
    padding: 1.4rem;
    margin-bottom: 1.3rem;
}

.compact-panel {
    margin-bottom: 0;
}

.panel-heading {
    display: flex;
    flex-wrap: wrap;
    align-items: baseline;
    justify-content: space-between;
    gap: 0.9rem;
    margin-bottom: 1rem;
}

.category-tiles,
.topic-grid,
.quick-link-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(220px, 1fr));
    gap: 1rem;
    margin-bottom: 1.3rem;
}

.reference-reading-stack,
.reference-group-section {
    display: grid;
    gap: 1rem;
}

.reference-group-section + .reference-group-section {
    margin-top: 1.5rem;
    padding-top: 1.2rem;
    border-top: 1px solid rgba(20, 63, 58, 0.1);
}

.compact-heading {
    margin-bottom: 0;
}

.category-tile,
.topic-card,
.info-card,
.reference-card,
.inline-link-card,
.reference-snippet {
    background: rgba(255, 255, 255, 0.78);
    border: 1px solid var(--line);
    border-radius: 16px;
}

.category-tile,
.inline-link-card {
    display: flex;
    flex-direction: column;
    gap: 0.3rem;
    text-decoration: none;
    transition: transform 140ms ease, box-shadow 140ms ease, border-color 140ms ease;
}

.category-tile {
    padding: 1.1rem;
}

.category-tile span {
    color: var(--muted);
}

.topic-card,
.reference-card,
.reference-snippet {
    padding: 1rem;
}

.topic-card-link {
    cursor: pointer;
    transition: transform 140ms ease, box-shadow 140ms ease, border-color 140ms ease;
}

.topic-card-link:hover,
.topic-card-link:focus-visible {
    transform: translateY(-2px);
    border-color: rgba(20, 63, 58, 0.22);
    box-shadow: 0 16px 34px rgba(18, 43, 39, 0.12);
    outline: none;
}

.topic-card-link:active {
    transform: translateY(0);
}

.topic-card h3,
.reference-snippet h3 {
    margin: 0.35rem 0 0.45rem;
}

.topic-page {
    display: grid;
    gap: 1.3rem;
}

.topic-header {
    padding: 1.6rem;
}

.topic-subcategory {
    margin: 0 0 0.5rem;
    font-size: 0.95rem;
}

.topic-header .tag-row {
    margin-top: 0.9rem;
}

.guidance-banner {
    padding: 1.35rem 1.5rem;
    border-left: 6px solid var(--accent);
    display: grid;
    gap: 0.8rem;
}

.topic-layout {
    display: grid;
    grid-template-columns: minmax(0, 1.75fr) minmax(280px, 0.9fr);
    gap: 1.25rem;
}

.topic-main,
.topic-side {
    display: grid;
    gap: 1.25rem;
}

.compact-summary-panel {
    margin-bottom: 0;
}

.summary-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(220px, 1fr));
    gap: 1rem;
}

.topic-utility-bar {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(220px, 1fr));
    gap: 0.8rem;
    margin-top: -0.2rem;
}

.site-overlay {
    position: fixed;
    inset: 0;
    z-index: 1000;
    display: grid;
    place-items: center;
    padding:
        max(1rem, env(safe-area-inset-top))
        1rem
        max(1rem, env(safe-area-inset-bottom))
        1rem;
    background: rgba(10, 22, 21, 0.62);
    backdrop-filter: blur(4px);
    overflow: auto;
    overscroll-behavior: contain;
}

.site-overlay[hidden],
.cookie-banner[hidden] {
    display: none !important;
}

.consent-dialog {
    width: min(720px, 100%);
    border-radius: 18px;
    background: var(--panel);
    border: 1px solid rgba(20, 63, 58, 0.14);
    box-shadow: 0 18px 44px rgba(18, 43, 39, 0.24);
    display: flex;
    flex-direction: column;
    max-height: min(90dvh, calc(var(--app-height, 100vh) - 2rem));
    max-height: min(90svh, calc(var(--app-height, 100vh) - 2rem));
    overflow: hidden;
}

.consent-dialog-header,
.consent-dialog-footer {
    flex: 0 0 auto;
    padding: 1.25rem 1.25rem 1rem;
}

.consent-dialog-header {
    padding-bottom: 0.85rem;
}

.consent-dialog-body {
    flex: 1 1 auto;
    overflow-y: auto;
    -webkit-overflow-scrolling: touch;
    overscroll-behavior: contain;
    padding: 0 1.25rem 1rem;
}

.consent-dialog-footer {
    padding-top: 0.95rem;
    padding-bottom: calc(1rem + env(safe-area-inset-bottom));
    border-top: 1px solid rgba(20, 63, 58, 0.1);
    background: rgba(249, 251, 248, 0.96);
}

.consent-dialog h2 {
    margin: 0;
    font-size: 1.5rem;
}

.consent-dialog p {
    margin: 0;
    color: var(--muted);
}

.consent-dialog-body > * + * {
    margin-top: 0.9rem;
}

.consent-actions,
.cookie-actions {
    display: flex;
    flex-wrap: wrap;
    gap: 0.75rem;
    align-items: center;
}

.consent-actions > * {
    min-height: 48px;
}

.secondary-button {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    padding: 0.95rem 1.15rem;
    border-radius: 12px;
    border: 1px solid var(--line);
    background: rgba(255, 255, 255, 0.7);
    color: var(--ink);
    text-decoration: none;
    font-weight: 600;
}

.cookie-banner {
    position: fixed;
    left: 1rem;
    right: 1rem;
    bottom: 1rem;
    z-index: 900;
    display: flex;
    flex-wrap: wrap;
    justify-content: space-between;
    gap: 1rem;
    padding: 1rem 1.1rem;
    border-radius: 16px;
    border: 1px solid rgba(20, 63, 58, 0.14);
    background: rgba(249, 251, 248, 0.97);
    box-shadow: 0 16px 34px rgba(18, 43, 39, 0.16);
}

.cookie-banner p,
.cookie-banner strong {
    margin: 0;
}

.cookie-banner p {
    color: var(--muted);
    max-width: 70ch;
}

@media (max-width: 720px) {
    .consent-dialog {
        width: 100%;
        border-radius: 16px;
    }

    .consent-actions {
        display: grid;
        grid-template-columns: 1fr;
        width: 100%;
    }

    .consent-actions > * {
        width: 100%;
        justify-content: center;
    }
}

.accordion-stack {
    display: grid;
    gap: 0.9rem;
}

.accordion-card {
    background: var(--panel);
    border: 1px solid rgba(20, 63, 58, 0.1);
    border-radius: 16px;
    box-shadow: var(--shadow);
    overflow: hidden;
    transition: border-color 180ms ease, box-shadow 180ms ease, background-color 180ms ease;
}

.accordion-card summary {
    list-style: none;
    cursor: pointer;
    padding: 1rem 1.15rem;
    font-weight: 700;
    background: rgba(20, 63, 58, 0.05);
    display: flex;
    align-items: center;
    gap: 0.75rem;
    width: 100%;
    user-select: none;
    transition: background-color 180ms ease, color 180ms ease;
}

.accordion-card summary::-webkit-details-marker {
    display: none;
}

.accordion-card summary::before {
    content: "▶";
    font-size: 0.78rem;
    color: var(--accent-strong);
    transform: rotate(0deg);
    transition: transform 180ms ease;
    flex: 0 0 auto;
}

.accordion-card[open] summary {
    border-bottom: 1px solid var(--line);
}

.accordion-card[open] summary::before {
    transform: rotate(90deg);
}

.accordion-card:hover {
    border-color: rgba(20, 63, 58, 0.2);
    box-shadow: 0 16px 36px rgba(18, 43, 39, 0.12);
}

.accordion-card:hover summary {
    background: rgba(20, 63, 58, 0.08);
}

.accordion-body {
    padding: 1rem 1.15rem 1.15rem;
    display: grid;
    gap: 1rem;
    opacity: 1;
    animation: accordion-fade 220ms ease;
}

@keyframes accordion-fade {
    from {
        opacity: 0;
        transform: translateY(-4px);
    }
    to {
        opacity: 1;
        transform: translateY(0);
    }
}

.engineering-assist-panel {
    border-top: 5px solid var(--accent-strong);
    background:
        linear-gradient(180deg, rgba(31, 90, 82, 0.05), transparent 24%),
        var(--panel);
}

.assist-grid {
    display: grid;
    gap: 1rem;
}

.assist-section {
    display: grid;
    gap: 0.75rem;
}

.assist-section h3,
.assist-section h4,
.decision-item h4,
.reference-snippet h4 {
    margin: 0;
}

.assist-subgrid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(220px, 1fr));
    gap: 1rem;
}

.decision-checklist {
    display: grid;
    gap: 0.8rem;
}

.decision-item {
    padding: 1rem;
    border-radius: 14px;
    border: 1px solid var(--line);
    background: rgba(20, 63, 58, 0.04);
}

.topic-sections {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(260px, 1fr));
    gap: 1rem;
}

.focused-sections .full-span {
    grid-column: 1 / -1;
}

.info-card {
    padding: 1.1rem 1.15rem;
}

.warning-callout {
    padding: 1rem;
    border-radius: 14px;
    border: 1px solid rgba(128, 90, 22, 0.18);
    background: var(--warning-bg);
}

.nested-card {
    margin-top: 1rem;
}

.single-column-mobile h3 {
    margin-top: 0;
}

.warning-card {
    background: var(--warning-bg);
    border-color: rgba(128, 90, 22, 0.18);
}

.alert-card {
    background: var(--alert-bg);
    border-color: rgba(125, 43, 34, 0.18);
}

.split-panel {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 1.2rem;
}

.link-list,
.reference-snippets,
.reference-list,
.tag-cloud {
    display: grid;
    gap: 0.75rem;
}

.inline-link-card {
    padding: 0.9rem 1rem;
}

.utility-link {
    display: flex;
    flex-direction: column;
    gap: 0.2rem;
    padding: 0.8rem 0.95rem;
    border: 1px solid rgba(20, 63, 58, 0.12);
    border-radius: 14px;
    background: rgba(249, 251, 248, 0.72);
    color: var(--ink);
    text-decoration: none;
    transition: border-color 140ms ease, background-color 140ms ease, transform 140ms ease, box-shadow 140ms ease;
}

.utility-link strong {
    font-size: 0.95rem;
}

.utility-link span {
    color: var(--muted);
    font-size: 0.84rem;
    letter-spacing: normal;
    text-transform: none;
    font-weight: 500;
}

.inline-link-card:hover,
.inline-link-card:focus-visible,
.utility-link:hover,
.utility-link:focus-visible,
.category-tile:hover,
.category-tile:focus-visible {
    border-color: rgba(20, 63, 58, 0.22);
    box-shadow: 0 16px 34px rgba(18, 43, 39, 0.12);
    transform: translateY(-2px);
    outline: none;
}

.tag-row,
.tag-cloud {
    display: flex;
    gap: 0.45rem;
    flex-wrap: wrap;
}

.tag-pill {
    display: inline-flex;
    align-items: center;
    padding: 0.35rem 0.65rem;
    border-radius: 999px;
    border: 1px solid rgba(31, 90, 82, 0.16);
    background: rgba(31, 90, 82, 0.08);
    color: var(--accent-strong);
    text-decoration: none;
    font-size: 0.82rem;
}

.link-pill {
    display: inline-flex;
    align-items: center;
    padding: 0.35rem 0.65rem;
    border-radius: 999px;
    border: 1px solid rgba(20, 63, 58, 0.12);
    background: rgba(20, 63, 58, 0.05);
    color: var(--accent-strong);
    text-decoration: none;
    font-size: 0.82rem;
}

.tag-pill:hover,
.tag-pill:focus-visible,
.link-pill:hover,
.link-pill:focus-visible {
    background: rgba(31, 90, 82, 0.12);
    border-color: rgba(20, 63, 58, 0.22);
    outline: none;
}

.bullet-list {
    margin: 0;
    padding-left: 1.1rem;
    display: grid;
    gap: 0.55rem;
}

.bullet-list li::marker {
    color: var(--accent);
}

.highlight-list li::marker {
    color: var(--accent-strong);
}

dl {
    margin: 0;
    display: grid;
    gap: 0.45rem;
}

dd {
    margin: 0 0 0.6rem;
}

.notes-form {
    display: grid;
    gap: 0.7rem;
}

.notes-guidance,
.notes-status {
    margin: 0;
    color: var(--muted);
    font-size: 0.9rem;
}

.notes-actions {
    display: flex;
    flex-wrap: wrap;
    gap: 0.75rem;
}

.save-message {
    margin-top: 0;
    padding: 0.7rem 0.8rem;
    border-radius: 12px;
    background: rgba(31, 90, 82, 0.09);
    color: var(--accent-strong);
}

.empty-state {
    padding: 1.4rem;
    border-radius: 16px;
    border: 1px dashed var(--line);
    background: rgba(255, 255, 255, 0.5);
}

@media (max-width: 980px) {
    .site-shell {
        grid-template-columns: 1fr;
    }

    .sidebar {
        position: static;
        height: auto;
        border-right: 0;
        border-bottom: 1px solid var(--line);
    }

    .content {
        padding: 1rem;
    }

    .breadcrumbs {
        margin-bottom: 0.8rem;
    }

    .sticky-context-bar {
        top: 0.5rem;
    }

    .topic-layout,
    .split-panel {
        grid-template-columns: 1fr;
    }

    .topic-utility-bar {
        grid-template-columns: 1fr;
    }

    .cookie-banner {
        left: 0.75rem;
        right: 0.75rem;
        bottom: 0.75rem;
    }
}

@media (max-width: 640px) {
    .search-row,
    .filter-row {
        flex-direction: column;
        align-items: stretch;
    }

    .hero,
    .panel,
    .topic-header,
    .guidance-banner {
        padding: 1.1rem;
        border-radius: 16px;
    }
}