:root {
    --bg-ink: #0f1318;
    --bg-deep: #1a2129;
    --bg-panel: rgba(35, 43, 53, 0.9);
    --bg-panel-strong: rgba(25, 32, 40, 0.96);
    --text-main: #e7ebee;
    --text-soft: #c7cdd2;
    --steel: #8f9ba6;
    --steel-bright: #dce2e7;
    --signal: #8ea1ae;
    --warning: #9b4b3f;
    --line: rgba(167, 181, 194, 0.22);
    --line-soft: rgba(167, 181, 194, 0.12);
    --shadow: rgba(0, 0, 0, 0.45);
    --font-display: 'Pathway Gothic One', sans-serif;
    --font-logo: 'Fascinate', serif;
    --font-body: 'IBM Plex Sans', sans-serif;
    --font-mono: 'IBM Plex Mono', monospace;
}

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

html {
    scroll-behavior: smooth;
}

body {
    min-height: 100vh;
    color: var(--text-main);
    font-family: var(--font-body);
    line-height: 1.45;
    background:
        radial-gradient(circle at top, rgba(142, 161, 174, 0.14), transparent 30%),
        radial-gradient(circle at 80% 20%, rgba(220, 226, 231, 0.07), transparent 25%),
        linear-gradient(180deg, #1d242c 0%, #12181f 40%, #0d1116 100%);
    letter-spacing: 0.01em;
}

body::before {
    content: "";
    position: fixed;
    inset: 0;
    pointer-events: none;
    background:
        linear-gradient(rgba(255, 255, 255, 0.015), rgba(0, 0, 0, 0.03)),
        repeating-linear-gradient(0deg, transparent 0 5px, rgba(255, 255, 255, 0.01) 5px 6px);
    opacity: 0.65;
}

.page-shell {
    position: relative;
}

.container {
    width: min(1180px, calc(100% - 2.25rem));
    margin: 0 auto;
}

.site-header {
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    z-index: 10;
    backdrop-filter: blur(8px);
    background: rgba(14, 18, 24, 0.84);
    border-bottom: 1px solid var(--line);
    box-shadow: 0 8px 24px rgba(0, 0, 0, 0.16);
}

.nav-bar {
    display: flex;
    justify-content: space-between;
    align-items: center;
    gap: 1.5rem;
    min-height: 72px;
    padding: 0.75rem 0;
}

main {
    padding-top: 180px;
}

.masthead-mark {
    display: flex;
    flex-direction: column;
    gap: 0.08rem;
}

.mark-kicker,
.section-kicker,
.eyebrow,
.signal-label,
.readout-label {
    font-family: var(--font-mono);
    font-size: 0.74rem;
    text-transform: uppercase;
    letter-spacing: 0.16em;
    color: var(--signal);
    display: flex;
    align-items: center;
    gap: 0.5rem;
}

.section-kicker::before,
.eyebrow::before {
    content: "//";
    opacity: 0.5;
}

.mark-name,
.plate-logo {
    font-family: var(--font-logo);
    color: var(--steel-bright);
}

h1,
h2,
h3,
.diagram-title,
.diagram-box-title {
    font-family: var(--font-display);
    letter-spacing: 0.02em;
}

.mark-name {
    font-size: var(--logo-size, 5rem);
    letter-spacing: 0.06em;
}

.mark-acronym {
    font-family: var(--font-mono);
    font-size: 0.72rem;
    text-transform: uppercase;
    letter-spacing: 0.13em;
    color: var(--signal);
    opacity: var(--acronym-opacity, 1);
    white-space: nowrap;
    overflow: hidden;
    line-height: 1.4;
}

.mark-kicker {
    max-width: 24ch;
}

.nav-links {
    list-style: none;
    display: flex;
    gap: 1.1rem;
    align-items: center;
}

.nav-links a,
.site-footer a {
    color: var(--text-soft);
    text-decoration: none;
    font-size: 1rem;
}

.nav-links a:hover,
.site-footer a:hover {
    color: var(--steel-bright);
}

.hero,
.principles,
.apparatus,
.instruments {
    position: relative;
    padding: 5rem 0;
}

.hero {
    padding-top: 5.75rem;
}

.hero-grid {
    display: grid;
    grid-template-columns: minmax(0, 1.2fr) minmax(300px, 0.9fr);
    gap: 1.5rem;
    align-items: stretch;
}

.hero > .container > .hero-copy {
    max-width: 72rem;
}

.hero-copy,
.hero-plate,
.principle-card,
.diagram-shell,
.apparatus-notes article,
.instrument-panel {
    position: relative;
    background: linear-gradient(180deg, rgba(41, 50, 60, 0.9), rgba(24, 31, 39, 0.98));
    border: 1px solid var(--line);
    box-shadow: 0 12px 28px var(--shadow), inset 0 1px 0 rgba(255, 255, 255, 0.03);
}

.hero-copy,
.hero-plate,
.instrument-panel,
.diagram-shell {
    border-radius: 14px;
}

.hero-copy {
    padding: 2rem;
}

.hero-copy::before,
.hero-plate::before,
.diagram-shell::before,
.instrument-panel::before {
    content: "";
    position: absolute;
    inset: 10px;
    border: 1px solid rgba(167, 181, 194, 0.14);
    border-radius: 10px;
    pointer-events: none;
}

.eyebrow {
    margin-bottom: 0.85rem;
}

h1 {
    font-size: clamp(2.6rem, 7vw, 4.6rem);
    line-height: 1.08;
    margin-bottom: 1rem;
    color: var(--text-main);
    max-width: 20ch;
}

.hero-lead {
    font-size: clamp(1.1rem, 2vw, 1.35rem);
    color: var(--text-soft);
    max-width: 34rem;
    margin-bottom: 1.4rem;
}

.hero-actions {
    display: flex;
    gap: 0.85rem;
    flex-wrap: wrap;
    margin-bottom: 1.5rem;
}

.btn {
    display: inline-flex;
    align-items: center;
    gap: 0.55rem;
    padding: 0.75rem 1.2rem;
    border-radius: 999px;
    border: 1px solid var(--line);
    text-decoration: none;
    font-weight: 600;
    font-size: 0.95rem;
    transition: transform 180ms ease, border-color 180ms ease, background-color 180ms ease;
}

.btn:hover {
    transform: translateY(-2px);
}

.btn-primary {
    background: linear-gradient(180deg, #dfe5ea, #98a5b1);
    color: #151a20;
}

.btn-secondary {
    background: rgba(142, 161, 174, 0.14);
    color: var(--text-main);
}

.btn-secondary:hover {
    border-color: rgba(142, 161, 174, 0.55);
}

.hero-facts {
    display: grid;
    grid-template-columns: repeat(3, minmax(0, 1fr));
    gap: 0.65rem;
}

.hero-facts div {
    padding: 0.8rem 0.9rem;
    border-radius: 10px;
    background: rgba(0, 0, 0, 0.16);
    border: 1px solid var(--line-soft);
}

.hero-facts dt {
    font-family: var(--font-mono);
    font-size: 0.74rem;
    color: var(--signal);
    text-transform: uppercase;
    letter-spacing: 0.14em;
    margin-bottom: 0.3rem;
}

.hero-facts dd {
    font-size: 0.98rem;
}

.hero-plate {
    display: flex;
    align-items: center;
    justify-content: center;
    padding: 1rem;
    background:
        radial-gradient(circle at top, rgba(184, 195, 205, 0.08), transparent 40%),
        linear-gradient(180deg, rgba(38, 46, 55, 0.98), rgba(23, 29, 36, 0.98));
}

.plate-frame {
    width: 100%;
    padding: 1.35rem;
    border-radius: 12px;
    border: 1px solid rgba(167, 181, 194, 0.22);
    background: linear-gradient(180deg, rgba(31, 38, 47, 0.96), rgba(20, 25, 31, 0.98));
}

.plate-header,
.plate-readout {
    display: grid;
    gap: 0.6rem;
}

.plate-header {
    grid-template-columns: repeat(2, minmax(0, 1fr));
    font-family: var(--font-mono);
    font-size: 0.74rem;
    color: var(--signal);
    text-transform: uppercase;
    letter-spacing: 0.16em;
}

.plate-header span:last-child {
    text-align: right;
}

.plate-logo {
    margin: 1.35rem 0 0.55rem;
    font-size: clamp(2.6rem, 8vw, 5rem);
    text-align: center;
    letter-spacing: 0.06em;
}

.plate-subtitle {
    text-align: center;
    font-size: 1.05rem;
    color: var(--text-soft);
}

.plate-rule {
    height: 1px;
    margin: 1.1rem 0;
    background: linear-gradient(90deg, transparent, rgba(167, 181, 194, 0.7), transparent);
}

.plate-readout {
    grid-template-columns: 1fr;
}

.plate-readout div {
    display: flex;
    justify-content: space-between;
    gap: 1rem;
    padding: 0.7rem 0;
    border-bottom: 1px solid var(--line-soft);
}

.readout-value {
    font-family: var(--font-mono);
    color: var(--steel-bright);
    font-size: 0.84rem;
}

.section-heading {
    max-width: 50rem;
    margin: 0 auto 2rem;
    text-align: center;
}

.section-heading .section-kicker {
    margin-bottom: 0.45rem;
}

h2 {
    font-size: clamp(1.9rem, 4vw, 3rem);
    line-height: 1.12;
    color: var(--text-main);
}

.principles-grid,
.apparatus-notes,
.instruments-grid {
    display: grid;
    gap: 1rem;
}

.principles-grid {
    grid-template-columns: repeat(2, minmax(0, 1fr));
}

.principle-card {
    border-radius: 12px;
    padding: 1.25rem;
}

.card-index {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    width: 1.9rem;
    height: 1.9rem;
    margin-bottom: 0.8rem;
    border-radius: 50%;
    border: 1px solid rgba(167, 181, 194, 0.28);
    color: var(--steel-bright);
    font-family: var(--font-display);
}

h3 {
    font-size: 1.25rem;
    margin-bottom: 0.5rem;
    color: var(--text-main);
}

.principle-card p,
.apparatus-notes p,
.instrument-panel li,
.site-footer p {
    font-size: 1rem;
    color: var(--text-soft);
}

code {
    padding: 0.08rem 0.35rem;
    border-radius: 6px;
    background: rgba(142, 161, 174, 0.12);
    color: var(--steel-bright);
    font-family: var(--font-mono);
    font-weight: 500;
    font-size: 0.9em;
}

.diagram-shell {
    padding: 0.9rem;
    overflow: hidden;
}

.apparatus-diagram {
    width: 100%;
    height: auto;
    display: block;
    border-radius: 8px;
}

.diagram-boundary {
    fill: none;
    stroke-width: 1.6;
}

.outer-shell {
    stroke: rgba(184, 195, 205, 0.34);
}

.inner-shell,
.container-zone,
.ward-zone {
    stroke: rgba(184, 195, 205, 0.18);
}

.container-zone {
    fill: rgba(24, 32, 41, 0.24);
}

.ward-zone {
    fill: rgba(142, 161, 174, 0.08);
}

.diagram-title {
    fill: var(--text-main);
    font-family: var(--font-display);
    font-size: 22px;
    letter-spacing: 0.08em;
}

.diagram-title.small {
    font-size: 17px;
}

.diagram-caption,
.diagram-box-text {
    fill: var(--text-soft);
    font-family: var(--font-body);
    font-size: 15px;
}

.diagram-box {
    fill: rgba(26, 33, 41, 0.92);
    stroke-width: 1.1;
}

.keeper-box,
.ctl-box,
.audit-box {
    stroke: rgba(184, 195, 205, 0.5);
}

.ward-box,
.chrome-box,
.llm-box {
    stroke: rgba(142, 161, 174, 0.42);
}

.diagram-box-title {
    fill: var(--steel-bright);
    font-family: var(--font-display);
    font-size: 20px;
    letter-spacing: 0.08em;
}

.diagram-box-text.tight {
    font-size: 14px;
}

.signal-line {
    fill: none;
    stroke: #b8c3cd;
    stroke-width: 2;
}

.signal-line.soft {
    stroke: rgba(142, 161, 174, 0.8);
    stroke-dasharray: 7 7;
}

.signal-label {
    fill: var(--signal);
    font-family: var(--font-mono);
    font-size: 11px;
    letter-spacing: 0.14em;
    text-transform: uppercase;
}

.apparatus-notes {
    margin-top: 1rem;
    grid-template-columns: repeat(3, minmax(0, 1fr));
}

.apparatus-notes article,
.instrument-panel {
    border-radius: 12px;
    padding: 1.15rem;
}

.instruments-grid {
    grid-template-columns: repeat(2, minmax(0, 1fr));
}

.instrument-panel.dark {
    background: linear-gradient(180deg, rgba(22, 28, 35, 0.98), rgba(16, 21, 27, 0.98));
}

.instrument-list {
    list-style: none;
    display: grid;
    gap: 0.75rem;
    margin-top: 1rem;
}

.instrument-list li {
    display: flex;
    align-items: baseline;
    gap: 0.7rem;
    padding-bottom: 0.7rem;
    border-bottom: 1px solid var(--line-soft);
}

.instrument-list span {
    min-width: 1.8rem;
    font-family: var(--font-mono);
    color: var(--steel-bright);
    font-size: 0.8rem;
}

.instrument-list.muted span {
    color: var(--warning);
}

.site-footer {
    padding: 2.5rem 0 3rem;
    border-top: 1px solid var(--line);
}

.footer-content {
    display: flex;
    justify-content: space-between;
    align-items: center;
    gap: 1rem;
}

.footer-logo {
    display: flex;
    flex-direction: column;
    gap: 0.2rem;
    margin-bottom: 0.6rem;
}

.footer-mark {
    font-family: var(--font-logo);
    font-size: 2.4rem;
    color: var(--steel-bright);
    letter-spacing: 0.06em;
    line-height: 1;
}

.footer-acronym {
    font-family: var(--font-mono);
    font-size: 0.68rem;
    text-transform: uppercase;
    letter-spacing: 0.13em;
    color: var(--signal);
}

.footer-tagline {
    font-size: 1rem;
    color: var(--text-soft);
}

@media (max-width: 980px) {
    .hero-grid,
    .principles-grid,
    .apparatus-notes,
    .instruments-grid,
    .hero-facts {
        grid-template-columns: 1fr;
    }

    .nav-bar,
    .footer-content {
        flex-direction: column;
        align-items: flex-start;
    }

    .nav-links {
        flex-wrap: wrap;
    }

    .diagram-shell {
        padding: 0.7rem;
    }

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

@media (max-width: 680px) {
    .hero,
    .principles,
    .apparatus,
    .instruments {
        padding: 4rem 0;
    }

    .container {
        width: min(100% - 1.3rem, 1180px);
    }

    .hero-copy,
    .hero-plate,
    .principle-card,
    .apparatus-notes article,
    .instrument-panel {
        padding: 1rem;
    }

    .btn {
        width: 100%;
        justify-content: center;
    }

    .plate-header,
    .plate-readout div {
        grid-template-columns: 1fr;
    }

    .plate-header span:last-child {
        text-align: left;
    }

    .nav-links {
        gap: 0.7rem;
    }

    .nav-links a {
        font-size: 0.95rem;
    }

    .hero-facts {
        grid-template-columns: 1fr;
    }

    .why-section {
        padding: 4rem 0;
    }
}

.why-section {
    position: relative;
    padding: 5rem 0;
}

.why-grid {
    display: grid;
    grid-template-columns: repeat(2, minmax(0, 1fr));
    gap: 1rem;
}

.why-card {
    position: relative;
    background: linear-gradient(180deg, rgba(41, 50, 60, 0.9), rgba(24, 31, 39, 0.98));
    border: 1px solid var(--line);
    border-left: 3px solid rgba(155, 75, 63, 0.7);
    box-shadow: 0 12px 28px var(--shadow), inset 0 1px 0 rgba(255, 255, 255, 0.03);
    border-radius: 12px;
    padding: 1.25rem;
}

.why-card h3 {
    color: var(--text-main);
    margin-bottom: 0.5rem;
}

.why-card p {
    font-size: 1rem;
    color: var(--text-soft);
}

/* ── Capabilities section ─────────────────────────────────────────────────── */

.capabilities-section {
    position: relative;
    padding: 5rem 0;
}

.cap-intro,
.cap-note {
    max-width: 68rem;
    margin: 0 auto 2rem;
    text-align: center;
    font-size: 1rem;
    color: var(--text-soft);
}

.cap-note {
    margin-top: 2rem;
    margin-bottom: 0;
}

.cap-grid {
    display: grid;
    grid-template-columns: repeat(3, minmax(0, 1fr));
    gap: 1rem;
}

.cap-card {
    position: relative;
    background: linear-gradient(180deg, rgba(41, 50, 60, 0.9), rgba(24, 31, 39, 0.98));
    border: 1px solid var(--line);
    border-radius: 12px;
    padding: 1.25rem;
    box-shadow: 0 12px 28px var(--shadow), inset 0 1px 0 rgba(255, 255, 255, 0.03);
    display: flex;
    flex-direction: column;
    gap: 0.75rem;
}

.cap-head {
    display: flex;
    align-items: baseline;
    flex-wrap: wrap;
    gap: 0.5rem;
}

.cap-name {
    font-family: var(--font-mono);
    font-size: 0.88rem;
    color: var(--steel-bright);
    background: rgba(142, 161, 174, 0.12);
    padding: 0.15rem 0.45rem;
    border-radius: 5px;
    letter-spacing: 0.02em;
}

.cap-category {
    font-family: var(--font-mono);
    font-size: 0.72rem;
    text-transform: uppercase;
    letter-spacing: 0.14em;
    color: var(--signal);
}

.cap-risk {
    font-family: var(--font-mono);
    font-size: 0.7rem;
    text-transform: uppercase;
    letter-spacing: 0.1em;
    padding: 0.1rem 0.4rem;
    border-radius: 4px;
    margin-left: auto;
}

.cap-risk--low      { color: #6aab79; background: rgba(106, 171, 121, 0.1); border: 1px solid rgba(106, 171, 121, 0.25); }
.cap-risk--medium   { color: #c9a84c; background: rgba(201, 168, 76, 0.1);  border: 1px solid rgba(201, 168, 76, 0.25); }
.cap-risk--high     { color: #c97a5a; background: rgba(201, 122, 90, 0.1);  border: 1px solid rgba(201, 122, 90, 0.25); }
.cap-risk--critical { color: #c94f4f; background: rgba(201, 79, 79, 0.12);  border: 1px solid rgba(201, 79, 79, 0.35); }

.cap-desc {
    font-size: 0.95rem;
    color: var(--text-soft);
}

.cap-fields {
    list-style: none;
    display: flex;
    flex-direction: column;
    gap: 0.3rem;
    flex: 1;
}

.cap-fields li {
    display: flex;
    align-items: baseline;
    gap: 0.45rem;
    font-size: 0.84rem;
    padding: 0.25rem 0;
    border-bottom: 1px solid var(--line-soft);
}

.field-name {
    font-family: var(--font-mono);
    color: var(--steel-bright);
    min-width: 8ch;
}

.field-type {
    font-family: var(--font-mono);
    font-size: 0.78rem;
    color: var(--signal);
}

.field-req {
    font-size: 0.76rem;
    color: rgba(201, 122, 90, 0.85);
    margin-left: auto;
}

.field-opt {
    font-size: 0.76rem;
    color: var(--steel);
    margin-left: auto;
}

.cap-returns {
    font-family: var(--font-mono);
    font-size: 0.8rem;
    color: var(--signal);
    padding-top: 0.25rem;
}

.cap-returns span {
    color: var(--steel-bright);
}

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

    .capabilities-section {
        padding: 4rem 0;
    }
}