/* ============================================================
   HOLOGRAPHISM — Shared Stylesheet
   holographism.css
   All pages link to this file
   ============================================================ */

/* ── VARIABLES ── */
:root {
  --black: #07080b;
  --deep: #0e1018;
  --surface: #141720;
  --raised: #1c2030;
  --border: rgba(180,160,100,0.15);
  --gold: #c4a265;
  --gold-bright: #e0be84;
  --gold-dim: rgba(196,162,101,0.35);
  --white: #f0ece2;
  --white-dim: rgba(240,236,226,0.6);
  --white-ghost: rgba(240,236,226,0.2);
  --interference: rgba(196,162,101,0.08);

  /* Responsive scale variables — adjusted by media queries */
  --base-font: 16px;
  --section-padding: 5rem 4rem;
  --hero-padding-v: 5rem;
  --hero-padding-h: 3rem;
  --heading-xl: 3.2rem;
  --heading-lg: 2.2rem;
  --heading-md: 1.6rem;
  --max-content: 1200px;
}

/* ── RESET ── */
*, *::before, *::after { box-sizing: border-box; margin: 0; padding: 0; }
html { scroll-behavior: smooth; }

body {
  background: var(--black);
  color: var(--white);
  font-family: 'Spectral', Georgia, serif;
  font-weight: 300;
  font-size: var(--base-font);
  line-height: 1.75;
  overflow-x: hidden;
}

/* ── INTERFERENCE BACKGROUND ── */
body::before {
  content: '';
  position: fixed;
  inset: 0;
  background-image:
    repeating-linear-gradient(0deg, transparent, transparent 79px, rgba(196,162,101,0.03) 80px),
    repeating-linear-gradient(90deg, transparent, transparent 79px, rgba(196,162,101,0.03) 80px);
  pointer-events: none;
  z-index: 0;
}

/* ── NAV ── */
nav {
  position: fixed;
  top: 0; left: 0; right: 0;
  z-index: 100;
  display: flex;
  align-items: stretch;
  justify-content: space-between;
  padding: 0 2rem;
  background: rgba(7,8,11,0.92);
  backdrop-filter: blur(12px);
  border-bottom: 1px solid var(--border);
  min-height: 64px;
}

.nav-logo {
  font-family: 'Cormorant Garamond', serif;
  font-size: 1.35rem;
  font-weight: 600;
  letter-spacing: 0.2em;
  text-transform: uppercase;
  color: var(--gold);
  text-decoration: none;
  display: flex;
  align-items: center;
  padding-right: 2rem;
  border-right: 1px solid var(--border);
}

.nav-center {
  flex: 1;
  display: flex;
  flex-direction: column;
  justify-content: center;
  padding: 0 1.5rem;
}

.nav-row {
  display: flex;
  align-items: center;
  gap: 1.8rem;
  padding: 0.3rem 0;
}

.nav-row a {
  color: var(--white-dim);
  text-decoration: none;
  font-size: 0.68rem;
  letter-spacing: 0.10em;
  text-transform: uppercase;
  font-family: 'Spectral', serif;
  font-weight: 400;
  white-space: nowrap;
  transition: color 0.25s;
}

.nav-row a:hover,
.nav-row a.active { color: var(--gold); }

.nav-instrument {
  display: flex;
  align-items: center;
  justify-content: center;
  padding: 0 2rem;
  border-left: 1px solid var(--border);
  text-decoration: none;
  cursor: pointer;
}

.nav-instrument-box {
  border: 1px solid var(--gold);
  padding: 0.55rem 1.4rem;
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  gap: 0.1rem;
  transition: background 0.25s, border-color 0.25s;
}

.nav-instrument-box:hover {
  background: rgba(196,162,101,0.08);
  border-color: var(--gold-bright);
}

.nav-instrument-line {
  font-family: 'Spectral', serif;
  font-size: 0.72rem;
  letter-spacing: 0.18em;
  text-transform: uppercase;
  color: var(--gold);
  line-height: 1.4;
  white-space: nowrap;
}

/* ── SECTIONS ── */
section {
  position: relative;
  z-index: 1;
  scroll-margin-top: 72px;
}

/* ── SECTION DIVIDER ── */
.section-divider {
  height: 1px;
  background: linear-gradient(90deg, transparent, rgba(196,162,101,0.3), transparent);
  position: relative;
  z-index: 1;
}

/* ── TYPOGRAPHY ── */
.section-eyebrow {
  font-family: 'Spectral', serif;
  font-size: 0.78rem;
  font-weight: 700;
  letter-spacing: 0.22em;
  text-transform: uppercase;
  color: var(--gold);
  margin-bottom: 1rem;
}

.section-heading {
  font-family: 'Cormorant Garamond', serif;
  font-size: calc(var(--heading-xl) * 1.15);
  font-weight: 400;
  line-height: 1.1;
  color: var(--white);
  margin-bottom: 1rem;
}

.section-heading em {
  font-style: italic;
  color: var(--gold);
}

/* ── HERO ── */
#hero {
  min-height: 100vh;
  display: grid;
  grid-template-columns: 1fr 1fr;
  padding-top: 64px;
  position: relative;
}

.hero-canvas {
  position: absolute;
  inset: 0;
  overflow: hidden;
  pointer-events: none;
}

.hero-left {
  padding: var(--hero-padding-v) var(--hero-padding-h) 4rem calc(var(--hero-padding-h) + 1rem);
  display: flex;
  flex-direction: column;
  justify-content: center;
  border-right: 1px solid var(--border);
  position: relative;
}

.hero-right {
  padding: var(--hero-padding-v) calc(var(--hero-padding-h) + 1rem) 4rem var(--hero-padding-h);
  display: flex;
  flex-direction: column;
  justify-content: center;
  position: relative;
}

.register-label {
  font-family: 'Spectral', serif;
  font-size: 0.68rem;
  letter-spacing: 0.22em;
  text-transform: uppercase;
  color: var(--gold);
  margin-bottom: 1.5rem;
  opacity: 0.7;
}

.hero-title {
  font-family: 'Cormorant Garamond', serif;
  font-size: var(--heading-xl);
  font-weight: 300;
  line-height: 1.08;
  color: var(--white);
  margin-bottom: 2rem;
}

.hero-title em { font-style: italic; color: var(--gold); }

.hero-body {
  font-size: 0.95rem;
  line-height: 1.85;
  color: var(--white-dim);
  max-width: 42ch;
  margin-bottom: 2rem;
}

.hero-cta {
  display: inline-flex;
  align-items: center;
  gap: 0.5rem;
  font-family: 'Spectral', serif;
  font-size: 0.78rem;
  letter-spacing: 0.18em;
  text-transform: uppercase;
  color: var(--white);
  text-decoration: none;
  padding: 0.9rem 2rem;
  border: 1px solid rgba(240,236,226,0.3);
  transition: border-color 0.25s, color 0.25s, background 0.25s;
}

.hero-cta:hover {
  color: var(--gold-bright);
  border-color: var(--gold);
  background: rgba(196,162,101,0.06);
}

/* ── ONTOLOGY ── */
#ontology {
  padding: var(--section-padding);
  background: var(--deep);
}

.ontology-inner {
  max-width: var(--max-content);
  margin: 0 auto;
}

.ontology-grid {
  display: grid;
  grid-template-columns: 1fr 1fr 1fr;
  gap: 3rem;
  margin-top: 3rem;
}

.ontology-card {
  padding: 2rem;
  background: var(--surface);
  border: 1px solid var(--border);
  border-top: 2px solid var(--gold-dim);
}

.ontology-card h3 {
  font-family: 'Cormorant Garamond', serif;
  font-size: 1.3rem;
  font-weight: 400;
  color: var(--gold);
  margin-bottom: 1rem;
}

.ontology-card p {
  font-size: 0.88rem;
  line-height: 1.85;
  color: var(--white-dim);
}

.ontology-statement {
  margin-top: 4rem;
  padding: 2.5rem 3rem;
  border-left: 3px solid var(--gold);
  background: var(--interference);
  font-family: 'Cormorant Garamond', serif;
  font-size: 1.25rem;
  font-style: italic;
  line-height: 1.6;
  color: rgba(240,236,226,0.85);
  max-width: 900px;
}

/* ── PRINCIPLES ── */
#principles {
  padding: var(--section-padding);
  background: var(--black);
}

.principles-inner {
  max-width: var(--max-content);
  margin: 0 auto;
}

.principles-header {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 4rem;
  align-items: start;
  margin-bottom: 4rem;
}

.principles-intro {
  font-size: 0.92rem;
  line-height: 1.9;
  color: var(--white-dim);
}

.principles-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 1.5rem;
}

.principle-card {
  padding: 1.5rem;
  background: var(--surface);
  border: 1px solid var(--border);
  cursor: pointer;
  transition: border-color 0.2s, background 0.2s;
  position: relative;
}

.principle-card:hover { border-color: var(--gold-dim); background: var(--raised); }
.principle-card.active { border-color: var(--gold); background: var(--raised); }

.principle-num {
  font-family: 'Spectral', serif;
  font-size: 0.65rem;
  letter-spacing: 0.2em;
  color: var(--gold-dim);
  margin-bottom: 0.5rem;
}

.principle-name {
  font-family: 'Cormorant Garamond', serif;
  font-size: 1.15rem;
  font-weight: 400;
  color: var(--white);
  margin-bottom: 0.5rem;
}

.principle-cat {
  font-size: 0.65rem;
  letter-spacing: 0.15em;
  text-transform: uppercase;
  color: var(--gold-dim);
}

.principle-detail {
  display: none;
  margin-top: 2rem;
  padding: 2rem;
  background: var(--raised);
  border: 1px solid var(--border);
}

.principle-detail.visible { display: grid; grid-template-columns: 1fr 1fr; gap: 3rem; }

.detail-col h4 {
  font-family: 'Spectral', serif;
  font-size: 0.62rem;
  letter-spacing: 0.2em;
  text-transform: uppercase;
  color: var(--gold);
  margin-bottom: 0.8rem;
}

.detail-col p {
  font-size: 0.88rem;
  line-height: 1.85;
  color: var(--white-dim);
}

/* ── INSTRUMENT ── */
#tool {
  padding: var(--section-padding);
  background: var(--deep);
}

.instrument-context {
  max-width: var(--max-content);
  margin: 0 auto;
}

.instrument-columns {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 5rem;
  margin-top: 3.5rem;
}

.instrument-col h3.instrument-col-head {
  font-family: 'Cormorant Garamond', serif;
  font-size: 2.2rem;
  font-weight: 600;
  font-style: italic;
  color: var(--gold);
  margin-bottom: 0.8rem;
  padding-bottom: 0.5rem;
  border-bottom: 1px solid rgba(196,162,101,0.2);
}

.instrument-col p {
  font-size: 0.92rem;
  line-height: 1.9;
  color: rgba(240,236,226,0.75);
  margin-bottom: 1rem;
}

.instrument-downloads {
  display: flex;
  gap: 0.8rem;
  margin-top: 2rem;
  flex-wrap: wrap;
}

.instrument-dl-btn {
  font-family: 'Spectral', serif;
  font-size: 0.68rem;
  letter-spacing: 0.14em;
  text-transform: uppercase;
  color: var(--gold);
  text-decoration: none;
  padding: 0.5rem 1rem;
  border: 1px solid rgba(196,162,101,0.35);
  transition: all 0.2s;
}

.instrument-dl-btn:hover {
  background: rgba(196,162,101,0.08);
  border-color: var(--gold);
}

.instrument-enter {
  margin-top: 4rem;
  display: flex;
  justify-content: center;
}

.instrument-enter-btn {
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  padding: 1.4rem 4rem;
  border: 1px solid var(--gold);
  text-decoration: none;
  gap: 0.1rem;
  transition: background 0.25s, border-color 0.25s;
}

.instrument-enter-btn:hover {
  background: rgba(196,162,101,0.08);
  border-color: var(--gold-bright);
}

.instrument-enter-line {
  font-family: 'Spectral', serif;
  font-size: 0.85rem;
  letter-spacing: 0.22em;
  text-transform: uppercase;
  color: var(--gold);
  line-height: 1.5;
}

/* ── INSTRUMENT WORKSPACE ── */
#instrument {
  padding: var(--section-padding);
  background: var(--black);
}

.instrument-workspace {
  max-width: var(--max-content);
  margin: 0 auto;
  display: grid;
  grid-template-columns: 1fr 2fr;
  gap: 5rem;
  align-items: start;
}

.instrument-workspace-head {
  font-family: 'Cormorant Garamond', serif;
  font-size: 2rem;
  font-weight: 600;
  line-height: 1.25;
  color: var(--white);
  margin-bottom: 1.2rem;
}

.instrument-workspace-body {
  font-size: 0.92rem;
  line-height: 1.85;
  color: rgba(240,236,226,0.85);
  font-weight: 400;
  margin-bottom: 0.8rem;
}

.instrument-code {
  font-family: 'Courier New', monospace;
  font-size: 0.82rem;
  color: var(--gold);
  background: rgba(196,162,101,0.1);
  padding: 0.1rem 0.4rem;
}

.instrument-workspace-commands {
  margin-top: 1.8rem;
  border-top: 1px solid rgba(196,162,101,0.15);
  padding-top: 1.2rem;
}

.instrument-cmd-label {
  font-family: 'Spectral', serif;
  font-size: 0.72rem;
  font-weight: 700;
  letter-spacing: 0.2em;
  text-transform: uppercase;
  color: var(--gold);
  margin-bottom: 0.8rem;
}

.instrument-cmd {
  font-family: 'Spectral', serif;
  font-size: 0.88rem;
  font-weight: 500;
  color: rgba(240,236,226,0.88);
  padding: 0.3rem 0;
  border-bottom: 1px solid rgba(196,162,101,0.15);
}

/* ── TOOL SIDEBAR CONTROLS ── */
.tool-interface-wrapper {
  display: flex;
  flex-direction: row;
  align-items: stretch;
  width: 100%;
  border: 1px solid rgba(138,106,48,0.25);
}

.tool-interface {
  flex: 1;
  min-width: 0;
  background: #F5F0E8;
  border: none;
  display: flex;
  flex-direction: column;
  min-height: 520px;
}

.tool-body-row {
  display: flex;
  flex-direction: row;
  flex: 1;
  min-height: 0;
}

.tool-sidebar {
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 0;
  background: #EDE8DC;
  border: none;
  border-left: 1px solid rgba(138,106,48,0.25);
  padding: 0.5rem 0;
  width: 52px;
  flex-shrink: 0;
  align-self: stretch;
}

.tool-sidebar-btn {
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  width: 100%;
  padding: 0.7rem 0;
  background: none;
  border: none;
  border-bottom: 1px solid rgba(138,106,48,0.12);
  cursor: pointer;
  transition: background 0.2s;
  gap: 0.2rem;
}

.tool-sidebar-btn:last-child { border-bottom: none; }
.tool-sidebar-btn:hover { background: rgba(138,106,48,0.12); }

.sidebar-icon {
  font-size: 1.1rem;
  font-weight: 900;
  color: #4A3010;
  line-height: 1;
}

.sidebar-label {
  font-family: 'Spectral', serif;
  font-size: 0.58rem;
  font-weight: 700;
  letter-spacing: 0.12em;
  text-transform: uppercase;
  color: #4A3010;
}

/* Run button flash on activation */
#tool-submit.running {
  background: #8A6A30;
  animation: runFlash 0.4s ease;
}

@keyframes runFlash {
  0% { background: #C4A265; }
  50% { background: #6A4820; }
  100% { background: #8A6A30; }
}

.tool-topbar {
  padding: 0.8rem 1.5rem;
  border-bottom: 1px solid rgba(138,106,48,0.2);
  display: flex;
  align-items: center;
  gap: 0.6rem;
  background: #EDE8DC;
}

.dot { width: 8px; height: 8px; border-radius: 50%; }
.dot-red { background: #cc4444; }
.dot-yellow { background: #cc8844; }
.dot-green { background: #448844; }

.tool-topbar-title {
  font-family: 'Spectral', serif;
  font-size: 0.82rem;
  font-weight: 700;
  letter-spacing: 0.15em;
  text-transform: uppercase;
  color: #5A4010;
  flex: 1;
}

.tool-output {
  flex: 1;
  min-width: 0;
  padding: 1.5rem;
  font-family: Georgia, 'Cormorant Garamond', serif;
  font-size: 1.05rem;
  font-weight: 600;
  line-height: 1.9;
  color: #12100E;
  background: #F2EBD9;
  overflow-y: auto;
  min-height: 420px;
  white-space: pre-wrap;
  word-break: break-word;
}

.tool-output .welcome {
  color: #4A3010;
  margin-bottom: 1rem;
  font-weight: 700;
  font-size: 0.92rem;
  font-family: 'Courier New', monospace;
}

.tool-output .user-line {
  color: #1A3A6A;
  margin-top: 1.2rem;
  font-weight: 700;
  font-size: 1rem;
}

.tool-output .response-line {
  color: #12100E;
  font-weight: 700;
  font-size: 1.1rem !important;
}

.tool-output .error-line {
  color: #884422;
  font-weight: 600;
}

.tool-input-area {
  border-top: 2px solid rgba(196,162,101,0.5);
  background: #EDE8DC;
  display: flex;
  flex-direction: row;
  align-items: flex-end;
  width: 100%;
  flex-shrink: 0;
}

.tool-prompt-symbol {
  padding: 1.2rem 1rem 1rem 1.5rem;
  font-family: 'Courier New', monospace;
  font-size: 0.85rem;
  color: #8A6A30;
  align-self: flex-start;
}

#tool-input {
  flex: 1;
  min-width: 0;
  width: 100%;
  background: transparent;
  border: none;
  outline: none;
  color: #12100E;
  font-family: Georgia, serif;
  font-size: 1.1rem;
  font-weight: 700;
  padding: 1rem 0.5rem 1rem 0;
  resize: vertical;
  min-height: 80px;
  max-height: 400px;
}

#tool-input::placeholder { color: rgba(26,24,32,0.35); font-style: italic; }

#tool-submit {
  padding: 0 1.8rem;
  background: #C4A265;
  border: none;
  border-left: 1px solid rgba(139,100,40,0.25);
  color: #12151E;
  font-family: 'Spectral', serif;
  font-size: 0.75rem;
  letter-spacing: 0.18em;
  text-transform: uppercase;
  cursor: pointer;
  font-weight: 600;
  align-self: stretch;
  transition: background 0.2s;
}

#tool-submit:hover { background: #D4B275; }

.api-key-notice { display: none; }

/* ── CHARACTERISTICS ── */
#characteristics {
  padding: var(--section-padding);
  background: var(--deep);
  border-top: 1px solid var(--border);
}

.char-inner {
  max-width: var(--max-content);
  margin: 0 auto;
}

.char-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 1.5rem;
  margin-top: 3rem;
}

.char-card {
  padding: 1.5rem;
  background: var(--surface);
  border: 1px solid var(--border);
  border-top: 2px solid var(--gold-dim);
}

.char-num {
  font-family: 'Spectral', serif;
  font-size: 0.62rem;
  letter-spacing: 0.2em;
  color: var(--gold-dim);
  margin-bottom: 0.4rem;
}

.char-name {
  font-family: 'Cormorant Garamond', serif;
  font-size: 1.1rem;
  color: var(--white);
  margin-bottom: 0.6rem;
}

.char-desc {
  font-size: 0.85rem;
  line-height: 1.8;
  color: var(--white-dim);
}

/* ── PUBLICATIONS ── */
#essays {
  padding: var(--section-padding);
  background: var(--black);
}

.essays-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 2rem;
  margin-top: 3rem;
  max-width: var(--max-content);
  margin-left: auto;
  margin-right: auto;
}

.essay-card {
  padding: 2rem;
  background: var(--surface);
  border: 1px solid var(--border);
  border-top: 2px solid var(--gold-dim);
  display: flex;
  flex-direction: column;
}

.essay-type {
  font-family: 'Spectral', serif;
  font-size: 0.62rem;
  letter-spacing: 0.18em;
  text-transform: uppercase;
  color: var(--gold-dim);
  margin-bottom: 0.8rem;
}

.essay-title {
  font-family: 'Cormorant Garamond', serif;
  font-size: 1.2rem;
  font-weight: 400;
  color: var(--white);
  line-height: 1.3;
  margin-bottom: 0.5rem;
}

.essay-subtitle {
  font-family: 'Spectral', serif;
  font-size: 0.78rem;
  font-style: italic;
  color: var(--gold-dim);
  margin-bottom: 1rem;
}

.essay-body {
  font-size: 0.85rem;
  line-height: 1.8;
  color: var(--white-dim);
  flex: 1;
}

/* ── CASE STUDIES ── */
#casestudies {
  padding: var(--section-padding);
  background: var(--deep);
}

/* ── ABOUT ── */
#about {
  padding: var(--section-padding);
  background: var(--black);
}

.about-inner {
  max-width: var(--max-content);
  margin: 0 auto;
  display: grid;
  grid-template-columns: 2fr 1fr;
  gap: 6rem;
  align-items: start;
}

.about-text h2 { margin-bottom: 2.5rem; }

.about-text p {
  font-size: 0.92rem;
  line-height: 1.9;
  color: var(--white-dim);
  margin-bottom: 1.2rem;
}

.about-credentials {
  border-left: 1px solid var(--border);
  padding-left: 3rem;
}

.credential-group {
  margin-bottom: 2rem;
}

.credential-label {
  font-family: 'Spectral', serif;
  font-size: 0.62rem;
  letter-spacing: 0.2em;
  text-transform: uppercase;
  color: var(--gold);
  margin-bottom: 0.6rem;
}

.credential-item {
  font-size: 0.85rem;
  line-height: 1.7;
  color: var(--white-dim);
  padding: 0.3rem 0;
  border-bottom: 1px solid var(--border);
}

/* ── FOOTER ── */
footer {
  padding: 3rem 4rem;
  background: var(--deep);
  border-top: 1px solid var(--border);
  display: flex;
  align-items: center;
  justify-content: space-between;
}

.footer-left {
  font-family: 'Spectral', serif;
  font-size: 0.78rem;
  color: var(--white-ghost);
  line-height: 1.7;
}

.footer-right {
  font-family: 'Spectral', serif;
  font-size: 0.72rem;
  color: var(--white-ghost);
  text-align: right;
  line-height: 1.7;
}

/* ── GRADIENT VIS ── */
.g-axis { margin-bottom: 1.5rem; }
.g-axis-label {
  display: flex;
  justify-content: space-between;
  font-size: 0.72rem;
  color: var(--white-dim);
  margin-bottom: 0.5rem;
}
.g-bar-track {
  height: 4px;
  background: var(--surface);
  border: 1px solid var(--border);
  position: relative;
  border-radius: 2px;
}
.g-bar-fill {
  height: 100%;
  background: linear-gradient(90deg, var(--gold-dim), var(--gold));
  border-radius: 2px;
  transition: width 0.6s ease;
}
.g-bar-marker {
  position: absolute;
  top: -4px;
  width: 12px;
  height: 12px;
  background: var(--gold);
  border-radius: 50%;
  transform: translateX(-50%);
  transition: left 0.6s ease;
}

/* ── LOADING DOTS ── */
.loading-dots::after {
  content: '';
  animation: dots 1.2s steps(4, end) infinite;
}
@keyframes dots {
  0%, 100% { content: ''; }
  25% { content: '.'; }
  50% { content: '..'; }
  75% { content: '...'; }
}

/* ============================================================
   RESPONSIVE BREAKPOINTS
   ============================================================ */

/* ── LARGE MONITORS (1800px+) ── */
@media (min-width: 1800px) {
  :root {
    --base-font: 17px;
    --section-padding: 7rem 6rem;
    --hero-padding-v: 7rem;
    --hero-padding-h: 5rem;
    --heading-xl: 3.8rem;
    --heading-lg: 2.6rem;
    --max-content: 1400px;
  }
  .nav-logo { font-size: 1.55rem; }
  .nav-row { gap: 2.2rem; }
  .nav-row a { font-size: 0.72rem; }
}

/* ── STANDARD LAPTOP (1200px - 1800px) ── */
@media (min-width: 1200px) and (max-width: 1799px) {
  :root {
    --base-font: 16px;
    --section-padding: 5rem 3.5rem;
    --hero-padding-v: 4rem;
    --hero-padding-h: 3rem;
    --heading-xl: 2.8rem;
    --heading-lg: 2rem;
    --max-content: 1100px;
  }
  .nav-logo { font-size: 1.2rem; }
  .nav-row { gap: 1.4rem; }
}

/* ── SMALL LAPTOP (900px - 1200px) ── */
@media (min-width: 900px) and (max-width: 1199px) {
  :root {
    --base-font: 15px;
    --section-padding: 4rem 2.5rem;
    --hero-padding-v: 3rem;
    --hero-padding-h: 2.5rem;
    --heading-xl: 2.4rem;
    --heading-lg: 1.8rem;
    --max-content: 960px;
  }
  .nav-logo { font-size: 1rem; letter-spacing: 0.15em; }
  .nav-row { gap: 1.2rem; }
  .nav-row a { font-size: 0.62rem; }
  .principles-grid { grid-template-columns: repeat(2, 1fr); }
  .char-grid { grid-template-columns: repeat(2, 1fr); }
  .essays-grid { grid-template-columns: repeat(2, 1fr); }
  .instrument-columns { gap: 3rem; }
  .instrument-workspace { gap: 3rem; }
}

/* ── TABLET / MOBILE (below 900px) ── */
@media (max-width: 899px) {
  :root {
    --base-font: 16px;
    --section-padding: 3rem 1.5rem;
    --hero-padding-v: 3rem;
    --hero-padding-h: 1.5rem;
    --heading-xl: 2rem;
    --heading-lg: 1.6rem;
    --max-content: 100%;
  }
  #hero { grid-template-columns: 1fr; }
  .hero-left { border-right: none; border-bottom: 1px solid var(--border); padding: 3rem 1.5rem; }
  .hero-right { padding: 3rem 1.5rem 4rem; }
  .ontology-grid { grid-template-columns: 1fr; }
  .principles-header { grid-template-columns: 1fr; }
  .principles-grid { grid-template-columns: repeat(2, 1fr); }
  .principle-detail.visible { grid-template-columns: 1fr; }
  .instrument-columns { grid-template-columns: 1fr; }
  .instrument-workspace { grid-template-columns: 1fr; }
  .char-grid { grid-template-columns: 1fr 1fr; }
  .essays-grid { grid-template-columns: 1fr; }
  .about-inner { grid-template-columns: 1fr; }
  .about-credentials { border-left: none; border-top: 1px solid var(--border); padding-left: 0; padding-top: 2rem; margin-top: 2rem; }
  .nav-center { display: none; }
  footer { flex-direction: column; gap: 1rem; text-align: center; }
}

/* ── INSTRUMENT LEFT RESIZE ── */
.instrument-workspace-left {
  resize: horizontal;
  overflow: auto;
  min-width: 240px;
  max-width: 50%;
}

/* ── INSTRUMENT SINGLE FLOW ── */
#tool, #instrument {
  scroll-margin-top: 64px;
}