/* ==========================================================================
   ParallelPilot project page
   Same structural language as longitudinal-workshop.github.io, recolored
   orange for this paper.
   ========================================================================== */

@import url('https://fonts.googleapis.com/css2?family=DM+Sans:opsz,wght@9..40,400;9..40,500;9..40,600;9..40,700&family=JetBrains+Mono:wght@400;500;600&display=swap');

:root {
    --header-height: 96px;
    --text-color: #221a14;
    --light-text-color: #6b5d52;
    --primary-color: #d1490f;
    --primary-color-dark: #a83a0c;
    --highlight-color: 255, 176, 102;   /* rgb triplet used inside gradients */
    --cta-color: #ffb066;
    --cta-color-hover: #d1490f;
    --secondary-color: #fff7f0;
    --border-color: #f1e0cf;
    --mono-font: 'JetBrains Mono', ui-monospace, SFMono-Regular, Menlo, monospace;
    --tint: #fff7f0; --tint-2: #fdece0; --tint-3: #fff1e6; --tint-4: #fbeee1; --tint-5: #fbf3ea; --tint-6: #fffaf5;
    --line: #f0c199; --pill-border: #f6d3ae;
}

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

main { margin-top: -2.5rem; }

html { scroll-behavior: smooth; scroll-padding-top: var(--header-height); }

body {
    font-family: 'DM Sans', sans-serif;
    font-weight: 400;
    line-height: 1.6;
    color: var(--text-color);
    background-color: #FFFFFF;
    padding-top: 96px;
    font-size: 15px;
}

p, li, ul, ol { font-weight: 400; }

h1, h2, h3 { line-height: 1.3; margin-bottom: 20px; }

h1 { font-size: 2.6rem; font-weight: 700; }

h2 {
    font-size: 1.55rem;
    font-weight: 500;
    border-bottom: 2px solid var(--primary-color);
    padding-bottom: 10px;
    display: inline-block;
}

h3 { font-size: 1.12rem; font-weight: 600; margin-top: 30px; }

p { margin-bottom: 15px; color: var(--light-text-color); }

a { color: var(--primary-color); text-decoration: none; }
a:hover { text-decoration: underline; }

.container { max-width: 980px; margin: 0 auto; padding: 0 20px; width: 100%; }

section { padding: 64px 0; position: relative; }
section:nth-child(odd) { background-color: var(--tint); }

.text-secondary { color: rgb(90, 78, 68); }

/* ---------------- Header ---------------- */
header {
    background-color: #FFFFFF;
    border-bottom: 1px solid var(--border-color);
    position: fixed;
    top: 0; left: 0; width: 100%;
    z-index: 1000;
    min-height: 64px;
    display: flex;
    align-items: center;
    box-shadow: 0 2px 12px 0 rgba(0,0,0,0.03);
    padding: 14px 0;
}

header .container {
    display: flex;
    flex-direction: row;
    align-items: center;
    justify-content: space-between;
    gap: 24px;
    width: 100%;
}

.header-left { display: flex; align-items: center; gap: 18px; min-width: 0; }

.back-wrap { position: absolute; left: 22px; top: 50%; transform: translateY(-50%); z-index: 1100; }
.back-link {
    display: inline-flex;
    align-items: center;
    gap: 6px;
    color: var(--text-color);
    white-space: nowrap;
    padding: 4px 12px 4px 6px;
    border-radius: 14px;
    transition: background .2s;
}
.back-link:hover { background: var(--tint-3); text-decoration: none; }
.back-home { position: relative; width: 38px; height: 36px; flex: 0 0 auto; }
.back-house { position: absolute; inset: 0; width: 38px; height: 36px; color: #221a14; transition: opacity .25s ease; }
.back-emoji {
    position: absolute;
    left: 50%; bottom: 4px;
    font-size: 0.95rem;
    line-height: 1;
    transform: translateX(-50%);
    transform-origin: 50% 85%;
    transition: transform .35s cubic-bezier(.34,1.56,.64,1);
    z-index: 2;
}
.back-link:hover .back-emoji, .back-link:focus-visible .back-emoji { transform: translateX(-50%) scale(2.7) rotate(-8deg); }
.back-link:hover .back-house, .back-link:focus-visible .back-house { opacity: 0.18; }
.back-arrow { width: 28px; height: 20px; color: #221a14; flex: 0 0 auto; }
.back-label { display: flex; flex-direction: column; line-height: 1.2; }
.back-title { font-size: 0.84rem; font-weight: 600; color: var(--text-color); }
.back-text { font-size: 0.7rem; font-weight: 500; color: #9c8b7c; }
@media (prefers-reduced-motion: reduce) { .back-emoji, .back-house { transition: none; } }
.back-preview {
    position: absolute;
    top: calc(100% + 12px);
    left: 0;
    width: 340px;
    background: #fff;
    border: 1px solid var(--border-color);
    border-radius: 12px;
    padding: 8px 8px 10px;
    box-shadow: 0 14px 40px rgba(0,0,0,.18);
    opacity: 0;
    visibility: hidden;
    transform: translateY(-6px);
    transition: opacity .2s, transform .2s, visibility .2s;
    pointer-events: none;
    z-index: 3000;
}
.back-preview img { display: block; width: 100%; height: auto; border-radius: 6px; border: 1px solid rgba(0,0,0,.06); }
.back-preview span { display: block; font-size: 0.78rem; color: var(--light-text-color); margin-top: 8px; text-align: center; }
.back-wrap:hover .back-preview, .back-wrap:focus-within .back-preview { opacity: 1; visibility: visible; transform: translateY(0); }
@media (hover: none) { .back-preview { display: none; } }
@media (max-width: 1460px) {
    .back-wrap { position: static; transform: none; margin-left: 4vw; }
    header { justify-content: space-between; }
    header .container { flex: 1; }
}
@media (max-width: 640px) { .back-label { display: none; } .back-wrap { margin-left: 3vw; } }

.logo {
    font-weight: 700;
    font-size: 1.15rem;
    color: var(--text-color);
    text-decoration: none;
    white-space: nowrap;
}
.logo-subtitle { color: #9c8b7c; font-weight: 500; }

nav ul {
    list-style: none;
    display: flex;
    gap: 2px;
    align-items: center;
}

nav a {
    text-decoration: none;
    color: var(--light-text-color);
    font-weight: 500;
    font-size: 0.92rem;
    padding: 8px 14px;
    border-radius: 6px;
    transition: color 0.3s, background 0.3s;
}

nav a.active, nav a:focus { background: var(--tint-4); color: var(--text-color); }
nav a:hover { color: var(--primary-color); background: var(--tint-5); text-decoration: none; }

.hamburger { display: none; flex-direction: column; justify-content: center; width: 34px; height: 34px; cursor: pointer; margin-left: 12px; }
.hamburger span { height: 4px; width: 26px; background: #221a14; margin: 4px 0; border-radius: 2px; display: block; }

/* ---------------- Hero ---------------- */
.hero {
    padding-top: var(--header-height);
    padding-bottom: 60px;
    text-align: center;
    background-color: #FFFFFF;
    position: relative;
    overflow: hidden;
}

/* fixed, low-opacity "fleet of agents" backdrop */
.agent-fleet-backdrop {
    position: fixed;
    top: 0; left: 0;
    width: 100vw; height: 100vh;
    pointer-events: none;
    z-index: -1;
    opacity: 0.05;
    display: flex;
    align-items: center;
    justify-content: center;
}
.agent-fleet-backdrop svg { width: min(1400px, 140vw); height: auto; }

.hero-eyebrow {
    color: rgb(158, 143, 128);
    font-size: 0.95rem;
    margin-bottom: 4px;
}
.hero-eyebrow a { color: rgb(158, 143, 128); }

.hero h1 { max-width: 820px; margin: 10px auto 0; }

.hero-authors {
    font-size: 1.05rem;
    color: var(--light-text-color);
    margin-top: 22px;
    margin-bottom: 6px;
}
.hero-institution { font-size: 0.98rem; color: #9c8b7c; margin-bottom: 14px; }
.hero-affil {
    font-size: 0.95rem;
    color: #9c8b7c;
    margin-bottom: 28px;
}

.hero-visual-container {
    display: flex;
    justify-content: center;
    align-items: center;
    gap: 3rem;
    margin: 2.5rem 0;
    flex-wrap: wrap;
}

.agent-icon-cluster { transform: scale(1); opacity: 0.9; }

.paper-thumb-container { flex: 0 0 auto; display: flex; flex-direction: column; align-items: center; }

.paper-thumb-link { display: block; transition: transform 0.3s ease; }
.paper-thumb-link:hover { transform: scale(1.04); text-decoration: none; }

.paper-thumb {
    width: 200px;
    height: auto;
    border-radius: 6px;
    background: #fff;
    box-shadow: 0 10px 30px rgba(0,0,0,0.14), 0 2px 8px rgba(0,0,0,0.08);
    border: 1px solid rgba(0,0,0,0.08);
}

.paper-thumb-caption { font-size: 13px; color: rgb(120, 105, 92); margin-top: 10px; }

/* Highlight marker effect, orange */
.highlight {
    font-weight: bolder;
    background: linear-gradient(104deg, rgba(var(--highlight-color),0) 0%, rgba(var(--highlight-color),1) 2.4%, rgba(var(--highlight-color),0.5) 5.8%, rgba(var(--highlight-color),0.1) 12%, rgba(var(--highlight-color),0.1) 90%, rgba(var(--highlight-color),0.7) 96%, rgba(var(--highlight-color),0.5) 98.5%, rgba(var(--highlight-color),0) 100%), linear-gradient(183deg, rgba(var(--highlight-color),0) 0%, rgba(var(--highlight-color),0.3) 7.9%, rgba(var(--highlight-color),0) 15%);
    padding: 0 0.18em;
    -webkit-box-decoration-break: clone;
    box-decoration-break: clone;
    border-radius: 7.5px;
}
.highlight-bold { font-weight: bold; color: #1a1310 !important; }

.cta-button {
    display: inline-flex;
    align-items: center;
    gap: 10px;
    background-color: var(--cta-color);
    color: #23150a !important;
    padding: 15px 30px;
    border-radius: 80px;
    text-decoration: none;
    font-weight: 600;
    font-size: 1.08rem;
    font-family: 'DM Sans';
    letter-spacing: 0.02em;
    box-shadow: 0 4px 18px 0 rgba(0,0,0,0.14);
    transition: background-color 0.25s ease, transform 0.2s ease, color .2s ease;
}
.cta-button:hover {
    background-color: var(--cta-color-hover);
    color: #fff !important;
    transform: translateY(-2px);
    text-decoration: none;
}
.cta-button-secondary {
    background-color: #fff;
    border: 1.5px solid var(--border-color);
    color: var(--text-color) !important;
    box-shadow: none;
}
.cta-button-secondary:hover { background-color: var(--secondary-color); color: var(--primary-color) !important; }

.cta-row { display: flex; gap: 14px; justify-content: center; flex-wrap: wrap; margin-top: 6px; }

.hero-note { margin-top: 18px; font-size: 0.92rem; color: rgb(120, 105, 92); }
.hero-note a { color: rgb(90, 78, 68); }

/* status pill */
.status-pill {
    display: inline-flex;
    align-items: center;
    gap: 6px;
    background: var(--tint-2);
    color: var(--primary-color-dark);
    border: 1px solid var(--pill-border);
    font-size: 0.8rem;
    font-weight: 600;
    padding: 5px 12px;
    border-radius: 40px;
    letter-spacing: 0.02em;
}

/* ---------------- Numbered section headers ---------------- */
.section-kicker {
    font-family: var(--mono-font);
    font-size: 0.85rem;
    color: var(--primary-color);
    letter-spacing: 0.04em;
    margin-bottom: 6px;
    display: block;
}
.section-intro { max-width: 760px; }

/* ---------------- Figure stream / connector line ---------------- */
.figure-stream {
    position: relative;
    margin-top: 40px;
    padding-left: 34px;
}
.figure-stream::before {
    content: "";
    position: absolute;
    left: 8px; top: 8px; bottom: 8px;
    width: 0;
    border-left: 2.5px dashed var(--line);
}
.figure-block { position: relative; margin-bottom: 64px; }
.figure-block:last-child { margin-bottom: 0; }
.figure-block::before {
    content: "";
    position: absolute;
    left: -34px; top: 6px;
    width: 15px; height: 15px;
    border-radius: 50%;
    background: var(--cta-color);
    border: 3px solid var(--primary-color);
}

.figure-card { background: transparent; border: none; box-shadow: none; }
.figure-card img {
    display: block; width: 100%; height: auto;
    box-sizing: border-box;
    padding: 36px;
    background: #fff;
    -webkit-mask-image: linear-gradient(to right, transparent 0, #000 36px, #000 calc(100% - 36px), transparent 100%), linear-gradient(to bottom, transparent 0, #000 36px, #000 calc(100% - 36px), transparent 100%);
    -webkit-mask-composite: source-in;
    mask-image: linear-gradient(to right, transparent 0, #000 36px, #000 calc(100% - 36px), transparent 100%), linear-gradient(to bottom, transparent 0, #000 36px, #000 calc(100% - 36px), transparent 100%);
    mask-composite: intersect;
}
.figure-card-pair { display: grid; grid-template-columns: 1.6fr 1fr; gap: 0; align-items: center; }
.figure-card-pair img { height: auto; }

.figure-label {
    font-family: var(--mono-font);
    font-size: 0.78rem;
    color: var(--primary-color);
    text-transform: uppercase;
    letter-spacing: 0.05em;
    margin-bottom: 6px;
    display: block;
}
.figure-title { font-size: 1.2rem; font-weight: 700; margin-bottom: 10px; color: var(--text-color); }
.figure-caption { font-size: 0.95rem; color: var(--light-text-color); margin-bottom: 16px; }

.bullet-list { list-style: none; margin: 0; padding: 0; }
.bullet-list li {
    position: relative;
    padding-left: 24px;
    margin-bottom: 10px;
    color: var(--light-text-color);
    font-size: 0.97rem;
}
.bullet-list li::before {
    content: "";
    position: absolute;
    left: 4px; top: 9px;
    width: 7px; height: 7px;
    border-radius: 50%;
    background: var(--primary-color);
}
.bullet-list strong { color: var(--text-color); }

.figure-meta { padding: 18px 8px 0; }

/* ---------------- Pillar / component grids ---------------- */
.pillar-grid, .component-grid {
    display: grid;
    grid-template-columns: repeat(5, 1fr);
    gap: 14px;
    margin-top: 22px;
}
.component-grid { grid-template-columns: repeat(3, 1fr); gap: 20px; }

.pillar-card, .component-card {
    background: #fff;
    border: 1px solid var(--border-color);
    border-radius: 12px;
    padding: 18px 16px;
    text-align: left;
}
.pillar-card { text-align: center; }
.pillar-letter {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    width: 34px; height: 34px;
    border-radius: 50%;
    background: var(--tint-2);
    color: var(--primary-color-dark);
    font-family: var(--mono-font);
    font-weight: 700;
    margin-bottom: 10px;
}
.pillar-card h4, .component-card h4 { font-size: 0.98rem; margin-bottom: 6px; color: var(--text-color); }
.pillar-card p, .component-card p { font-size: 0.85rem; margin-bottom: 0; }
.component-card .figure-label { margin-bottom: 10px; }

/* ---------------- Summary box ---------------- */
.summary-box {
    margin-top: 36px;
    background: var(--tint-6);
    border: 1px solid var(--border-color);
    border-left: 4px solid var(--primary-color);
    border-radius: 10px;
    padding: 22px 26px;
}
.summary-box h4 { font-size: 0.95rem; text-transform: uppercase; letter-spacing: 0.04em; color: var(--primary-color-dark); margin-bottom: 12px; font-family: var(--mono-font); font-weight: 600; }

/* ---------------- Stat tiles ---------------- */
.stat-grid {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 16px;
    margin-top: 30px;
}
.stat-tile {
    background: #fff;
    border: 1px solid var(--border-color);
    border-radius: 12px;
    padding: 20px 18px;
    text-align: left;
}
.stat-number {
    font-family: var(--mono-font);
    font-size: 1.9rem;
    font-weight: 700;
    color: var(--primary-color);
    font-variant-numeric: tabular-nums;
    display: block;
    margin-bottom: 6px;
}
.stat-label { font-size: 0.88rem; color: var(--light-text-color); }

.callout-box {
    margin-top: 36px;
    background: linear-gradient(180deg, #fff, var(--tint));
    border: 1.5px solid var(--line);
    border-radius: 14px;
    padding: 28px 30px;
}
.callout-box h3 { margin-top: 0; }
.callout-quote {
    font-family: var(--mono-font);
    font-size: 0.92rem;
    color: var(--primary-color-dark);
    border-left: 3px solid var(--primary-color);
    padding-left: 14px;
    margin: 16px 0;
}

/* ---------------- BibTeX ---------------- */
.bibtex-wrap { position: relative; margin-top: 26px; }
.bibtex-box {
    background: #241a12;
    color: #f5e4d3;
    border-radius: 12px;
    padding: 24px 26px;
    font-family: var(--mono-font);
    font-size: 0.85rem;
    line-height: 1.7;
    overflow-x: auto;
    white-space: pre;
}
.bibtex-box .k { color: var(--cta-color); }
.bibtex-box .v { color: #d7e3ff; }

.copy-btn {
    position: absolute;
    top: 14px; right: 14px;
    background: #3a291b;
    color: #f5e4d3;
    border: 1px solid #55402c;
    border-radius: 8px;
    padding: 7px 13px;
    font-family: var(--mono-font);
    font-size: 0.78rem;
    cursor: pointer;
    transition: background .2s;
}
.copy-btn:hover { background: #4a3624; }
.copy-btn.copied { background: var(--primary-color); border-color: var(--primary-color); color: #fff; }

/* ---------------- Footer ---------------- */
footer {
    background-color: #221a14;
    color: #f1e4d8;
    text-align: center;
    padding: 40px 20px;
}
footer p { color: #cbb9a8; margin-bottom: 10px; font-size: 0.9rem; }
footer a { color: var(--cta-color); font-weight: 500; }

/* ---------------- Responsive ---------------- */
@media (max-width: 900px) {
    header .container { padding: 0 6vw; }
    nav ul { flex-direction: column; position: fixed; top: 58px; right: 0; left: 0; background: #fff; max-height: 0; overflow: hidden; transition: max-height .3s; z-index: 2000; box-shadow: none; }
    nav ul.open { max-height: 400px; padding: 10px 0 18px; box-shadow: 0 4px 16px rgba(0,0,0,.08); }
    nav ul li { width: 100%; text-align: right; padding: 0 22px; }
    nav ul li a { display: block; padding: 12px 0; }
    .hamburger { display: flex; }
    .header-left { flex: 1 1 auto; overflow: hidden; }
}

@media (max-width: 768px) {
    h1 { font-size: 2rem; }
    h2 { font-size: 1.6rem; }
    .container { padding-left: 6vw; padding-right: 6vw; }
    .figure-card-pair { grid-template-columns: 1fr; }
    .pillar-grid { grid-template-columns: repeat(2, 1fr); }
    .pillar-grid > *:nth-child(5) { grid-column: 1 / -1; }
    .component-grid { grid-template-columns: 1fr; }
    .stat-grid { grid-template-columns: repeat(2, 1fr); }
    .figure-stream { padding-left: 26px; }
    .figure-block::before { left: -26px; }
}

@media (max-width: 480px) {
    .stat-grid { grid-template-columns: 1fr; }
    .pillar-grid { grid-template-columns: 1fr 1fr; }
    .header-left { gap: 8px; }
    .logo-subtitle { display: none; }
    .logo { font-size: 0.98rem; }
}

/* faint ParallelPilot logos in the hero */
.hero-logos { position: absolute; inset: 0; pointer-events: none; z-index: 0; overflow: hidden; }
.hero .container { position: relative; z-index: 1; }
.hl { position: absolute; mix-blend-mode: multiply; opacity: 0.13; height: auto; }
.hl1 { width: 280px; left: 3%; top: 14%; transform: rotate(-8deg); }
.hl2 { width: 220px; right: 4%; top: 8%; transform: rotate(10deg); }
.hl3 { width: 200px; left: 8%; bottom: 8%; transform: rotate(6deg); }
.hl4 { width: 300px; right: 6%; bottom: 10%; transform: rotate(-5deg); }
@media (max-width: 768px) { .hl { opacity: 0.09; width: 150px; } }

/* ---------------- Hero: one-screen landing ---------------- */
body { padding-top: 64px; }
main { margin-top: 0; }
html { scroll-padding-top: 72px; }
.hero {
    padding: 28px 0 30px;
    min-height: calc(100vh - 64px);
    min-height: calc(100svh - 64px);
    display: flex;
    flex-direction: column;
    justify-content: center;
}
.hero h1 { font-size: 2.1rem; max-width: 1000px; margin: 0 auto; }
.hero h1 .ln { display: block; }
.hero-authors { font-size: 1rem; margin-top: 16px; margin-bottom: 2px; }
.hero-institution { font-size: 0.93rem; margin-bottom: 10px; }
.hero-affil { margin-bottom: 0; }
.hero-visual-container { margin: 18px 0 16px; gap: 2rem; }
.paper-thumb { width: 136px; }
.paper-thumb-caption { font-size: 12px; margin-top: 6px; }
.cta-row { gap: 10px; margin-top: 0; }
.cta-button { padding: 10px 22px; font-size: 0.95rem; gap: 8px; }
.link-row { display: flex; gap: 8px; justify-content: center; flex-wrap: wrap; margin-top: 12px; }
.link-button {
    display: inline-flex;
    align-items: center;
    gap: 5px;
    padding: 5px 14px;
    border-radius: 40px;
    border: 1px solid var(--border-color);
    background: #fff;
    color: var(--light-text-color) !important;
    font-size: 0.82rem;
    font-weight: 500;
    transition: color .2s, border-color .2s, background .2s;
}
.link-button:hover { color: var(--primary-color-dark) !important; border-color: var(--line); background: var(--tint-6); text-decoration: none; }
.hero-note { margin-top: 14px; margin-bottom: 0; font-size: 0.88rem; }
@media (max-width: 768px) {
    .hero h1 { font-size: 1.6rem; }
    .hero { min-height: 0; padding: 28px 0 36px; }
}
@media (max-height: 760px) and (min-width: 769px) {
    .hero h1 { font-size: 1.9rem; }
    .paper-thumb { width: 112px; }
    .hero-visual-container { margin: 12px 0 12px; }
}

/* ---------------- Figure sizes, galleries, quotes ---------------- */
.figure-card img { --fade: 36px; padding: var(--fade);
    -webkit-mask-image: linear-gradient(to right, transparent 0, #000 var(--fade), #000 calc(100% - var(--fade)), transparent 100%), linear-gradient(to bottom, transparent 0, #000 var(--fade), #000 calc(100% - var(--fade)), transparent 100%);
    mask-image: linear-gradient(to right, transparent 0, #000 var(--fade), #000 calc(100% - var(--fade)), transparent 100%), linear-gradient(to bottom, transparent 0, #000 var(--fade), #000 calc(100% - var(--fade)), transparent 100%);
}
.figure-card.fig-md > img { max-width: 760px; margin: 0 auto; }
.figure-card.fig-sm > img { max-width: 580px; margin: 0 auto; }
.figure-card.fig-xs > img { max-width: 440px; margin: 0 auto; }
.figure-gallery { display: grid; grid-template-columns: repeat(var(--cols, 3), minmax(0, 1fr)); gap: 4px; align-items: start; }
.figure-gallery img { --fade: 16px; }
.figure-gallery.gallery-center { align-items: center; }
@media (max-width: 768px) {
    .figure-gallery { grid-template-columns: repeat(2, minmax(0, 1fr)); }
    .figure-card img { --fade: 20px; }
    .figure-gallery img { --fade: 10px; }
}

.quote-grid { display: grid; grid-template-columns: repeat(auto-fit, minmax(250px, 1fr)); gap: 16px; margin-top: 14px; }
.quote-card {
    position: relative;
    background: #fff;
    border: 1px solid var(--border-color);
    border-radius: 12px;
    padding: 22px 20px 16px;
    display: flex;
    flex-direction: column;
    justify-content: space-between;
    gap: 12px;
}
.quote-card::before {
    content: "\201C";
    position: absolute;
    top: 2px; left: 14px;
    font-family: Georgia, 'Times New Roman', serif;
    font-size: 2.8rem;
    line-height: 1;
    color: var(--cta-color);
}
.quote-text { margin: 8px 0 0; font-size: 0.95rem; line-height: 1.55; color: var(--text-color); }
.quote-who { font-family: var(--mono-font); font-size: 0.75rem; color: var(--primary-color); letter-spacing: 0.03em; }

/* ---------------- Type scale below the hero ---------------- */
.logo { font-size: 1.05rem; }
nav a { font-size: 0.86rem; }
.section-kicker { font-size: 0.76rem; }
.section-intro { font-size: 0.95rem; }
.figure-label { font-size: 0.7rem; }
.figure-title { font-size: 1.04rem; }
.figure-caption { font-size: 0.87rem; }
.bullet-list li { font-size: 0.9rem; margin-bottom: 8px; }
.bullet-list li::before { top: 8px; width: 6px; height: 6px; }
.pillar-card h4, .component-card h4 { font-size: 0.9rem; }
.pillar-card p, .component-card p { font-size: 0.8rem; }
.summary-box { padding: 18px 22px; }
.summary-box h4 { font-size: 0.78rem; }
.summary-box p { font-size: 0.92rem; }
.stat-number { font-size: 1.5rem; }
.stat-label { font-size: 0.8rem; }
.stat-tile { padding: 16px 16px; }
.callout-box { padding: 24px 26px; }
.callout-quote { font-size: 0.86rem; }
.quote-text { font-size: 0.88rem; }
.quote-card::before { font-size: 2.3rem; }
.quote-who { font-size: 0.7rem; }
.bibtex-box { font-size: 0.78rem; }
footer p { font-size: 0.84rem; }
@media (max-width: 768px) { h2 { font-size: 1.3rem; } }

/* ---------------- SPEAR visuals (spear.html) ---------------- */
:root { --sp-a: #3f6aa8; --sp-a-tint: #e9f0fa; --sp-r: #7a55a8; --sp-r-tint: #f2ecfa; }
.sp-diagram-wrap { background: #fff; border: 1px solid var(--border-color); border-radius: 14px; padding: 18px 16px 14px; }
.sp-diagram { display: block; width: 100%; height: auto; font-family: 'DM Sans', sans-serif; }
.sp-ring { fill: none; stroke: var(--line); stroke-width: 3; }
.sp-arrow { fill: var(--primary-color); }
.sp-node { fill: var(--primary-color); stroke: #fff; stroke-width: 3; }
.sp-node-t { fill: #fff; font-size: 19px; font-weight: 700; text-anchor: middle; font-family: 'JetBrains Mono', monospace; }
.sp-lbl { fill: var(--text-color); font-size: 15px; font-weight: 600; }
.sp-center { fill: var(--light-text-color); font-size: 12.5px; text-anchor: middle; font-family: 'JetBrains Mono', monospace; }
.sp-center-2 { fill: #9c8b7c; }
.sp-faded { opacity: .55; }
.sp-faded-2 { opacity: .3; }
.sp-dots { fill: var(--light-text-color); font-size: 22px; text-anchor: middle; letter-spacing: 2px; }
.sp-task { fill: var(--light-text-color); font-size: 13px; text-anchor: middle; font-family: 'JetBrains Mono', monospace; }
.sp-link { fill: none; stroke-width: 2.5; stroke-dasharray: 7 6; }
.sp-link-a { stroke: var(--sp-a); }
.sp-link-r { stroke: var(--sp-r); }
.sp-mk-a { fill: var(--sp-a); }
.sp-mk-r { fill: var(--sp-r); }
.sp-badge-a circle { fill: var(--sp-a); stroke: #fff; stroke-width: 3; }
.sp-badge-r circle { fill: var(--sp-r); stroke: #fff; stroke-width: 3; }
.sp-badge-a text, .sp-badge-r text { fill: #fff; font-size: 16px; font-weight: 700; text-anchor: middle; font-family: 'JetBrains Mono', monospace; }
.sp-link-lbl { fill: var(--text-color); font-size: 13.5px; font-weight: 500; }
.sp-legend { display: flex; flex-wrap: wrap; gap: 8px 18px; justify-content: center; margin-top: 6px; font-size: 0.8rem; color: var(--light-text-color); }
.sp-legend span { display: inline-flex; align-items: center; gap: 6px; }
.sp-dot { display: inline-block; width: 10px; height: 10px; border-radius: 50%; }
.sp-dot-core { background: var(--primary-color); }
.sp-dot-a { background: var(--sp-a); }
.sp-dot-r { background: var(--sp-r); }

.sp-group { margin-top: 6px; }
.sp-group + .sp-group { margin-top: 26px; }
.sp-group-h { font-size: 0.9rem; font-weight: 600; color: var(--text-color); margin-bottom: 12px; display: flex; align-items: center; gap: 10px; flex-wrap: wrap; }
.sp-group-tag { font-family: var(--mono-font); font-size: 0.68rem; font-weight: 500; letter-spacing: .04em; text-transform: uppercase; padding: 3px 9px; border-radius: 20px; }
.sp-tag-core { background: var(--tint-2); color: var(--primary-color-dark); }
.sp-tag-across { background: linear-gradient(90deg, var(--sp-a-tint), var(--sp-r-tint)); color: #4b3f6b; }
.sp-grid { display: grid; gap: 14px; }
.sp-grid-3 { grid-template-columns: repeat(3, minmax(0, 1fr)); }
.sp-grid-2 { grid-template-columns: repeat(2, minmax(0, 1fr)); }
.sp-card { --c: var(--primary-color); --ct: var(--tint-6); background: #fff; border: 1px solid var(--border-color); border-top: 3px solid var(--c); border-radius: 12px; padding: 16px 16px 14px; display: flex; flex-direction: column; gap: 10px; }
.sp-card-a { --c: var(--sp-a); --ct: var(--sp-a-tint); }
.sp-card-r { --c: var(--sp-r); --ct: var(--sp-r-tint); }
.sp-head { display: flex; align-items: center; gap: 10px; }
.sp-letter { flex: 0 0 auto; width: 34px; height: 34px; border-radius: 50%; background: var(--c, var(--primary-color)); color: #fff; font-family: var(--mono-font); font-weight: 700; font-size: 1rem; display: inline-flex; align-items: center; justify-content: center; }
.sp-name { font-weight: 700; font-size: 0.98rem; color: var(--text-color); line-height: 1.2; }
.sp-sub { font-family: var(--mono-font); font-size: 0.7rem; color: var(--c); letter-spacing: .03em; }
.sp-q { font-size: 0.88rem; color: var(--text-color); margin: 0; line-height: 1.5; }
.sp-ex { background: var(--ct); border-radius: 9px; padding: 10px 11px; display: flex; flex-direction: column; gap: 6px; margin-top: auto; }
.sp-ex-label { font-family: var(--mono-font); font-size: 0.66rem; color: var(--light-text-color); letter-spacing: .02em; }
.sp-ex-row { display: grid; grid-template-columns: 16px 1fr; gap: 4px; font-size: 0.8rem; line-height: 1.45; color: var(--text-color); }
.sp-ex-row > span:first-child { font-weight: 700; }
.sp-ex-bad > span:first-child { color: #b3413a; }
.sp-ex-bad > span:last-child { color: var(--light-text-color); }
.sp-ex-good > span:first-child { color: #2f8a57; }

.sp-reframe { background: #fff; border: 1px solid var(--border-color); border-radius: 14px; padding: 18px 20px; display: flex; flex-direction: column; gap: 14px; }
.sp-rf-row { display: flex; flex-direction: column; gap: 8px; }
.sp-rf-label { font-family: var(--mono-font); font-size: 0.7rem; text-transform: uppercase; letter-spacing: .05em; color: #9c8b7c; }
.sp-rf-label-new { color: var(--primary-color); }
.sp-chain { display: flex; flex-wrap: wrap; align-items: center; gap: 6px 8px; }
.sp-chain > span { font-size: 0.84rem; padding: 5px 11px; border-radius: 8px; background: #f4f1ee; color: var(--light-text-color); }
.sp-chain > span.sp-chain-end { border: 1px dashed #cbbfb2; background: #fff; }
.sp-chain i { font-style: normal; color: #b8a999; }
.sp-chain-loop > span { background: var(--tint-2); color: var(--primary-color-dark); font-weight: 600; }
.sp-chain-loop > span.sp-chain-note { background: none; font-weight: 400; color: var(--light-text-color); padding-left: 2px; }
.sp-chain-loop i.sp-loopback { color: var(--primary-color); font-size: 1.1rem; }
.sp-definition { font-size: 1.02rem; line-height: 1.6; color: var(--text-color); margin: 6px 0 0; }

.sp-found { display: flex; flex-direction: column; gap: 8px; margin-top: 8px; }
.sp-found-row { --c: var(--primary-color); display: grid; grid-template-columns: 34px 120px 1fr; align-items: center; gap: 12px; background: #fff; border: 1px solid var(--border-color); border-radius: 10px; padding: 8px 12px; }
.sp-found-row.sp-card-a { --c: var(--sp-a); }
.sp-found-row.sp-card-r { --c: var(--sp-r); }
.sp-found-name { font-weight: 600; font-size: 0.9rem; }
.sp-chips { display: flex; flex-wrap: wrap; gap: 6px; }
.sp-chips > span { font-size: 0.78rem; padding: 3px 10px; border-radius: 20px; background: #f4f1ee; color: var(--text-color); }
.sp-chips-lg { margin-top: 8px; gap: 8px; }
.sp-chips-lg > span { font-size: 0.86rem; padding: 6px 14px; background: var(--tint-2); color: var(--primary-color-dark); font-weight: 600; }
.sp-chips-accent > span { background: var(--tint-2); color: var(--primary-color-dark); font-weight: 600; }
.sp-roles { display: grid; grid-template-columns: 1fr auto 1fr; align-items: center; gap: 14px; margin-top: 8px; background: #fff; border: 1px solid var(--border-color); border-radius: 14px; padding: 16px 18px; }
.sp-role-from, .sp-role-to { display: flex; flex-direction: column; gap: 8px; }
.sp-role-arrow { font-style: normal; font-size: 1.4rem; color: var(--primary-color); }
@media (max-width: 768px) {
  .sp-grid-3, .sp-grid-2 { grid-template-columns: 1fr; }
  .sp-found-row { grid-template-columns: 34px 1fr; }
  .sp-found-row .sp-chips { grid-column: 1 / -1; }
  .sp-roles { grid-template-columns: 1fr; }
  .sp-role-arrow { transform: rotate(90deg); justify-self: center; }
  .sp-diagram-wrap { overflow-x: auto; }
  .sp-diagram { min-width: 620px; }
}

/* SPEAR: HCI foundations with short introductions */
.sp-found-row { align-items: start; padding: 12px 14px; }
.sp-found-row > .sp-letter, .sp-found-row > .sp-found-name { margin-top: 2px; }
.sp-found-row > .sp-found-name { line-height: 34px; margin-top: 0; }
.sp-theories { display: grid; grid-template-columns: repeat(auto-fill, minmax(220px, 1fr)); gap: 10px 18px; }
.sp-th { display: flex; flex-direction: column; gap: 2px; }
.sp-th-name { font-weight: 700; font-size: 0.86rem; color: var(--c, var(--primary-color)); }
.sp-th-def { font-size: 0.8rem; line-height: 1.45; color: var(--text-color); }
.sp-th-cite { font-family: var(--mono-font); font-size: 0.66rem; color: var(--light-text-color); }
@media (max-width: 768px) { .sp-theories { grid-template-columns: 1fr; } }