/* =============================================================
   Vibe Research tutorial — Kami palette adapted from ahu-talk.
   Parchment surface, single ink-blue accent, serif-led, no italic.
   ============================================================= */

:root {
  --paper-base:    #f5f4ed;
  --paper-ivory:   #faf9f5;
  --paper-sand:    #e8e6dc;
  --paper-deep:    #efece1;

  --ink-blue:      #1B365D;
  --ink-blue-light:#2D5A8A;
  --ink-tint:      #E4ECF5;

  --near-black:    #141413;
  --dark-warm:     #3d3d3a;
  --charcoal:      #4d4c48;
  --olive:         #5e5d59;
  --stone:         #87867f;

  --border-cream:  #e8e5da;
  --border-warm:   #e0ddd2;
  --border-soft:   #e5e3d8;

  --ring-warm:     #d1cfc5;
  --ring-deep:     #c2c0b6;

  --color-gap:        #b53333;
  --color-gap-bg:     #f3e6e0;
  --color-idea:       var(--ink-blue);
  --color-idea-bg:    var(--ink-tint);
  --color-evidence:   #4a6b3a;
  --color-evidence-bg:#e9ead9;
  --color-purple:     #6b4a7a;

  --serif: "Newsreader", "Source Serif 4", "TsangerJinKai02",
           "Source Han Serif SC", "Songti SC", Georgia, serif;
  --sans:  "Inter", -apple-system, BlinkMacSystemFont, "PingFang SC",
           "Microsoft YaHei", sans-serif;
  --mono:  "JetBrains Mono", "SF Mono", Consolas, monospace;
}

* { box-sizing: border-box; }

html, body {
  margin: 0;
  padding: 0;
  background: var(--paper-base);
  color: var(--near-black);
  font-family: var(--serif);
  line-height: 1.6;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
  scroll-behavior: smooth;
}

a { color: var(--ink-blue); text-decoration: none; border-bottom: 1px solid var(--ink-blue-light); }
a:hover { color: var(--ink-blue-light); }

strong { color: var(--ink-blue); font-weight: 500; }

code, kbd, pre {
  font-family: var(--mono);
  font-size: 0.92em;
}
code {
  background: var(--paper-sand);
  padding: 0.08em 0.4em;
  border-radius: 3px;
}

::selection { background: var(--ink-tint); color: var(--ink-blue); }

/* ============= NAV ============= */
.nav {
  position: sticky;
  top: 0;
  z-index: 50;
  background: rgba(245, 244, 237, 0.92);
  backdrop-filter: blur(8px);
  border-bottom: 1px solid var(--border-soft);
}
.nav-inner {
  max-width: 1100px;
  margin: 0 auto;
  padding: 0.85rem 1.5rem;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 1rem;
  flex-wrap: wrap;
}
.brand {
  font-family: var(--serif);
  font-weight: 500;
  font-size: 1rem;
  color: var(--near-black);
  border: none;
  letter-spacing: 0.01em;
}
.brand-dot { color: var(--ink-blue); margin: 0 0.2em; }
.nav-links {
  display: flex;
  gap: 1.4rem;
  font-family: var(--sans);
  font-size: 0.82rem;
  letter-spacing: 0.04em;
}
.nav-links a {
  color: var(--olive);
  border: none;
  text-transform: uppercase;
  font-weight: 500;
  white-space: nowrap;
}
.nav-links a:hover { color: var(--ink-blue); }

/* ============= LAYOUT ============= */
.section {
  padding: 5.5rem 1.5rem;
  border-bottom: 1px solid var(--border-soft);
  scroll-margin-top: 92px;
}
.section-alt { background: var(--paper-deep); }
.section-hero { padding-top: 4rem; padding-bottom: 4rem; }
.section-terminal { background: var(--paper-deep); }

.container {
  max-width: 1100px;
  margin: 0 auto;
}
.container.narrow { max-width: 760px; }

.eyebrow {
  font-family: var(--sans);
  text-transform: uppercase;
  font-size: 0.72rem;
  font-weight: 500;
  letter-spacing: 0.14em;
  color: var(--olive);
  margin-bottom: 0.7rem;
}

h1, h2, h3 {
  font-family: var(--serif);
  font-weight: 500;
  letter-spacing: 0;
  color: var(--near-black);
  line-height: 1.2;
}
h2 {
  font-size: 1.85rem;
  border-left: 3px solid var(--ink-blue);
  padding-left: 0.7rem;
  margin: 0 0 1.2rem;
}
.lede {
  font-size: 1.05rem;
  color: var(--charcoal);
  max-width: 720px;
  line-height: 1.65;
  margin: 0 0 2rem;
}
.dim { color: var(--stone); }

/* ============= HERO ============= */
.hero-title {
  font-size: 2.7rem;
  line-height: 1.16;
  margin: 0.4rem 0 1.2rem;
  font-weight: 500;
}
.hero-sub {
  font-size: 1.1rem;
  color: var(--charcoal);
  max-width: 680px;
  margin: 0 0 2.4rem;
}

.comparison {
  display: grid;
  grid-template-columns: 1fr auto 1fr;
  gap: 1.4rem;
  align-items: stretch;
  margin: 0 0 2rem;
}
.card {
  background: var(--paper-ivory);
  border: 1px solid var(--border-cream);
  border-left: 3px solid var(--ink-blue);
  border-radius: 4px;
  padding: 1.2rem 1.4rem;
  box-shadow: 0 0 0 1px var(--ring-warm);
  display: flex;
  flex-direction: column;
}
.card-red   { border-left-color: var(--color-gap); }
.card-blue  { border-left-color: var(--ink-blue); }
.card-tag {
  font-family: var(--sans);
  font-size: 0.72rem;
  text-transform: uppercase;
  letter-spacing: 0.1em;
  color: var(--olive);
  font-weight: 500;
}
.card-num {
  font-family: var(--serif);
  font-size: 4.3rem;
  font-weight: 500;
  line-height: 1;
  color: var(--ink-blue);
  margin: 0.7rem 0 0.6rem;
  font-feature-settings: "tnum";
}
.card-num .unit {
  font-size: 1.4rem;
  margin-left: 0.3rem;
  color: var(--charcoal);
  font-weight: 400;
}
.card-meta { color: var(--charcoal); margin: 0.2rem 0 0.6rem; font-size: 0.96rem;}
.card-cite { font-size: 0.78rem; color: var(--stone); margin-top: auto; }

.vs {
  align-self: center;
  font-family: var(--sans);
  text-transform: uppercase;
  letter-spacing: 0.2em;
  font-size: 0.78rem;
  color: var(--stone);
  font-weight: 500;
}

.hero-callout {
  background: var(--ink-tint);
  border-left: 3px solid var(--ink-blue);
  padding: 1rem 1.3rem;
  border-radius: 3px;
  font-size: 1.08rem;
  margin: 1.6rem 0 2rem;
}

.papers-strip { margin-top: 2.4rem; }
.papers-strip-label {
  font-family: var(--sans);
  font-size: 0.74rem;
  text-transform: uppercase;
  letter-spacing: 0.12em;
  color: var(--olive);
  margin-bottom: 0.6rem;
}
.papers-strip-track {
  display: grid;
  grid-template-columns: repeat(16, 1fr);
  gap: 4px;
}
.paper-tile {
  height: 64px;
  background: var(--paper-ivory);
  border: 1px solid var(--border-cream);
  border-radius: 3px;
  padding: 5px 6px;
  font-size: 0.62rem;
  line-height: 1.15;
  color: var(--charcoal);
  position: relative;
  cursor: default;
  transition: transform 0.18s, box-shadow 0.18s;
}
.paper-tile:hover {
  transform: translateY(-2px);
  box-shadow: 0 4px 12px rgba(27, 54, 93, 0.12);
  border-color: var(--ink-blue-light);
}
.paper-tile.starred { border-left: 3px solid var(--ink-blue); }
.paper-tile .pt-month {
  font-family: var(--sans);
  color: var(--stone);
  font-size: 0.6rem;
}
.paper-tile .pt-title { font-weight: 500; color: var(--ink-blue); margin-top: 2px; }
.paper-tile .pt-venue { color: var(--olive); margin-top: 1px; }

/* ============= PHILOSOPHY BAR ============= */
.bar-widget {
  background: var(--paper-ivory);
  border: 1px solid var(--border-cream);
  border-radius: 6px;
  padding: 1.6rem 1.8rem;
  margin: 1.6rem 0;
  box-shadow: 0 0 0 1px var(--ring-warm);
}
.bar-track {
  height: 28px;
  display: flex;
  border-radius: 4px;
  overflow: hidden;
  border: 1px solid var(--border-warm);
}
.bar-impl    { background: var(--color-gap-bg); transition: width 0.18s; }
.bar-physics { background: var(--ink-tint); transition: width 0.18s; }
.bar-impl::before, .bar-physics::before {
  content: '';
}
.bar-labels {
  display: flex;
  justify-content: space-between;
  margin-top: 0.7rem;
  font-family: var(--sans);
  font-size: 0.85rem;
  color: var(--charcoal);
}
.bar-labels strong { font-feature-settings: "tnum"; margin-left: 0.3rem; }
.dot {
  display: inline-block;
  width: 0.7rem;
  height: 0.7rem;
  border-radius: 2px;
  margin-right: 0.4rem;
  vertical-align: middle;
}
.dot-red  { background: var(--color-gap); }
.dot-blue { background: var(--ink-blue); }

#bar-slider {
  width: 100%;
  margin: 1rem 0 0;
  accent-color: var(--ink-blue);
}
.bar-help {
  font-family: var(--sans);
  font-size: 0.8rem;
  color: var(--olive);
  margin-top: 0.5rem;
}

.bar-output {
  background: var(--paper-base);
  border-left: 3px solid var(--ink-blue);
  padding: 0.9rem 1.1rem;
  margin-top: 1.2rem;
  font-size: 1.05rem;
  border-radius: 3px;
}
.bar-output strong {
  font-size: 1.6rem;
  font-feature-settings: "tnum";
  margin: 0 0.2em;
}
.bar-output-sub {
  font-size: 0.86rem;
  color: var(--olive);
  margin-top: 0.3rem;
  font-family: var(--sans);
}

.callout {
  border-left: 3px solid var(--ink-blue);
  background: var(--ink-tint);
  padding: 1.1rem 1.3rem;
  border-radius: 3px;
  margin-top: 1.4rem;
  font-size: 1rem;
  line-height: 1.6;
}
.callout-idea { background: var(--ink-tint); border-left-color: var(--ink-blue); }
.callout-warn { background: var(--color-gap-bg); border-left-color: var(--color-gap); }

.footnote {
  margin-top: 0.9rem;
  font-size: 0.78rem;
  color: var(--stone);
  font-family: var(--sans);
  line-height: 1.55;
}
.disclaimer {
  background: var(--color-gap-bg);
  border-left: 3px solid var(--color-gap);
  padding: 0.8rem 1.1rem;
  border-radius: 3px;
  color: var(--dark-warm);
  margin-top: 1.6rem;
}

/* ============= TERMINAL ============= */
.demo-tabs {
  display: flex;
  gap: 0.5rem;
  flex-wrap: wrap;
  margin: 1.5rem 0 1rem;
}
.demo-tab {
  background: var(--paper-ivory);
  border: 1px solid var(--border-warm);
  border-radius: 3px;
  padding: 0.55rem 1rem;
  font-family: var(--sans);
  font-size: 0.86rem;
  color: var(--charcoal);
  cursor: pointer;
  transition: all 0.16s;
}
.demo-tab:hover { border-color: var(--ink-blue-light); color: var(--ink-blue); }
.demo-tab.active {
  background: var(--ink-blue);
  color: var(--paper-ivory);
  border-color: var(--ink-blue);
}
.demo-tab .tab-sub {
  display: block;
  font-size: 0.74rem;
  color: inherit;
  opacity: 0.78;
  margin-top: 1px;
}

.terminal-shell {
  background: #1c1d1a;
  border-radius: 8px;
  box-shadow:
    0 0 0 1px var(--ring-warm),
    0 18px 48px -16px rgba(20, 20, 19, 0.45);
  overflow: hidden;
  margin: 1rem 0 1rem;
}
.terminal-titlebar {
  background: #2a2b27;
  padding: 0.65rem 1rem;
  display: flex;
  align-items: center;
  gap: 0.4rem;
}
.terminal-titlebar .dot {
  width: 0.72rem;
  height: 0.72rem;
  border-radius: 50%;
  margin: 0;
}
.terminal-titlebar .d-red { background: #ff5f56; }
.terminal-titlebar .d-yel { background: #ffbd2e; }
.terminal-titlebar .d-grn { background: #27c93f; }
.terminal-title {
  margin-left: 0.8rem;
  font-family: var(--mono);
  font-size: 0.78rem;
  color: #b8b6a8;
}

.terminal-body {
  padding: 1.4rem 1.5rem 1.6rem;
  min-height: 460px;
  max-height: 600px;
  overflow-y: auto;
  font-family: var(--mono);
  font-size: 0.84rem;
  line-height: 1.62;
  color: #e0ddd2;
  scroll-behavior: smooth;
}
.terminal-body:focus { outline: none; }

/* terminal step types */
.t-step { margin: 0 0 1.2rem; animation: fadein 0.3s; }
@keyframes fadein {
  from { opacity: 0; transform: translateY(4px); }
  to   { opacity: 1; transform: none; }
}

.t-prompt { color: #5db8ff; font-weight: 500; }
.t-user {
  background: rgba(93, 184, 255, 0.06);
  border-left: 2px solid #5db8ff;
  padding: 0.6rem 0.9rem;
  border-radius: 3px;
  white-space: pre-wrap;
  word-break: break-word;
}
.t-user::before {
  content: "> ";
  color: #5db8ff;
  font-weight: 500;
  margin-right: 0.2rem;
}

.t-thinking {
  color: #9a9787;
  font-style: italic;
  font-family: var(--mono);
  border-left: 2px solid #5e5d59;
  padding: 0.4rem 0.9rem;
  font-size: 0.78rem;
  white-space: pre-wrap;
}
.t-thinking::before {
  content: "✺ thinking · ";
  font-style: normal;
  color: #6e6c64;
  font-size: 0.74rem;
}

.t-tool {
  background: rgba(255, 255, 255, 0.04);
  border: 1px solid #3a3b36;
  border-left: 2px solid #d8b86a;
  border-radius: 3px;
  padding: 0.55rem 0.85rem;
  font-size: 0.8rem;
}
.t-tool-name { color: #d8b86a; font-weight: 500; }
.t-tool-args { color: #c4c1b3; margin-left: 0.4rem; }
.t-tool-result { color: #9a9787; font-size: 0.76rem; margin-top: 0.3rem; white-space: pre-wrap; }

.t-output {
  white-space: pre-wrap;
  color: #e8e5da;
}

.t-result {
  background: #0f1010;
  border: 1px solid #2a2b27;
  border-left: 2px solid #6db66d;
  border-radius: 3px;
  padding: 0.7rem 0.9rem;
  white-space: pre-wrap;
  color: #b6c4a8;
  font-size: 0.78rem;
}
.t-result.warn { border-left-color: #d97755; color: #d4a392; }

.t-note {
  color: #8a8779;
  font-style: italic;
  font-family: var(--serif);
  font-size: 0.95rem;
  text-align: center;
  padding: 0.6rem 1.4rem;
  border-top: 1px dashed #3a3b36;
  border-bottom: 1px dashed #3a3b36;
}
.t-note::before { content: "—— "; }
.t-note::after  { content: " ——"; }

/* Filter modal */
.t-filter {
  background: var(--paper-base);
  color: var(--near-black);
  border: 1px solid var(--color-gap);
  border-left: 3px solid var(--color-gap);
  padding: 1.2rem 1.4rem;
  border-radius: 4px;
  font-family: var(--serif);
  font-size: 0.94rem;
  margin: 0.4rem 0;
  box-shadow: 0 0 0 1px var(--ring-warm);
}
.t-filter-title {
  font-weight: 500;
  color: var(--color-gap);
  font-size: 0.88rem;
  text-transform: uppercase;
  letter-spacing: 0.06em;
  margin-bottom: 0.5rem;
  font-family: var(--sans);
}
.t-filter-body { white-space: pre-wrap; line-height: 1.55; }
.t-filter-confirm {
  margin-top: 0.9rem;
  background: var(--color-gap);
  color: var(--paper-ivory);
  border: none;
  padding: 0.5rem 1.1rem;
  border-radius: 3px;
  font-family: var(--sans);
  font-weight: 500;
  font-size: 0.84rem;
  cursor: pointer;
  letter-spacing: 0.02em;
}
.t-filter-confirm:hover { background: #962727; }
.t-filter.consumed { opacity: 0.55; }
.t-filter.consumed .t-filter-confirm { display: none; }

.terminal-controls {
  background: #2a2b27;
  padding: 0.65rem 1rem;
  display: flex;
  align-items: center;
  gap: 0.6rem;
  flex-wrap: wrap;
  border-top: 1px solid #3a3b36;
}
.ctrl {
  background: #1c1d1a;
  color: #d8d6c8;
  border: 1px solid #3a3b36;
  border-radius: 3px;
  padding: 0.35rem 0.85rem;
  font-family: var(--sans);
  font-size: 0.8rem;
  cursor: pointer;
  letter-spacing: 0.02em;
}
.ctrl:hover { border-color: var(--ink-blue-light); color: #fff; }
.ctrl-primary {
  background: var(--ink-blue);
  border-color: var(--ink-blue);
  color: #fff;
}
.ctrl-primary:hover { background: var(--ink-blue-light); }
.ctrl:disabled { opacity: 0.4; cursor: default; }

.ctrl-progress {
  margin-left: auto;
  font-family: var(--mono);
  font-size: 0.76rem;
  color: #9a9787;
  font-feature-settings: "tnum";
}
.ctrl-speed {
  font-family: var(--sans);
  font-size: 0.78rem;
  color: #9a9787;
}
.ctrl-speed select {
  background: #1c1d1a;
  color: #d8d6c8;
  border: 1px solid #3a3b36;
  border-radius: 3px;
  padding: 0.18rem 0.4rem;
  font-family: var(--sans);
  font-size: 0.78rem;
  margin-left: 0.3rem;
}

.demo-summary {
  background: var(--paper-ivory);
  border: 1px solid var(--border-cream);
  border-left: 3px solid var(--color-evidence);
  border-radius: 3px;
  padding: 0.9rem 1.2rem;
  margin-top: 1rem;
  font-size: 0.95rem;
  color: var(--charcoal);
}

/* ============= SKILL GALLERY ============= */
.stage-tabs {
  display: flex;
  gap: 0.4rem;
  flex-wrap: wrap;
  margin: 1.4rem 0 1.4rem;
}
.stage-tab {
  background: transparent;
  border: 1px solid var(--border-warm);
  border-radius: 999px;
  padding: 0.4rem 0.95rem;
  font-family: var(--sans);
  font-size: 0.84rem;
  color: var(--charcoal);
  cursor: pointer;
  transition: all 0.16s;
}
.stage-tab:hover { border-color: var(--ink-blue-light); color: var(--ink-blue); }
.stage-tab.active {
  background: var(--ink-blue);
  color: #fff;
  border-color: var(--ink-blue);
}
.stage-tab .stage-hint {
  display: inline-block;
  margin-left: 0.4rem;
  opacity: 0.7;
  font-size: 0.76rem;
}

.skill-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(280px, 1fr));
  gap: 1rem;
}
.skill-card {
  background: var(--paper-ivory);
  border: 1px solid var(--border-cream);
  border-left: 3px solid var(--ink-blue);
  border-radius: 4px;
  padding: 1.1rem 1.2rem;
  box-shadow: 0 0 0 1px var(--ring-warm);
  cursor: pointer;
  transition: transform 0.16s, box-shadow 0.16s;
  position: relative;
}
.skill-card:hover {
  transform: translateY(-2px);
  box-shadow:
    0 0 0 1px var(--ring-deep),
    0 8px 22px -10px rgba(27, 54, 93, 0.18);
}
.skill-card.color-blue   { border-left-color: var(--ink-blue); }
.skill-card.color-red    { border-left-color: var(--color-gap); }
.skill-card.color-green  { border-left-color: var(--color-evidence); }
.skill-card.color-purple { border-left-color: var(--color-purple); }

.skill-name {
  font-family: var(--mono);
  font-size: 0.86rem;
  color: var(--ink-blue);
  font-weight: 500;
}
.skill-cn {
  font-family: var(--serif);
  font-size: 1rem;
  color: var(--near-black);
  margin: 0.2rem 0 0.6rem;
  font-weight: 500;
}
.skill-row {
  font-size: 0.82rem;
  color: var(--charcoal);
  margin: 0.3rem 0;
  font-family: var(--sans);
}
.skill-row b {
  color: var(--olive);
  font-weight: 500;
  text-transform: uppercase;
  letter-spacing: 0.06em;
  font-size: 0.7rem;
  margin-right: 0.4rem;
}
.skill-invoke {
  margin-top: 0.7rem;
  background: var(--paper-sand);
  font-family: var(--mono);
  font-size: 0.78rem;
  padding: 0.4rem 0.6rem;
  border-radius: 3px;
  color: var(--dark-warm);
  white-space: nowrap;
  overflow: hidden;
  text-overflow: ellipsis;
}
.skill-card .copy-hint {
  position: absolute;
  top: 0.6rem;
  right: 0.7rem;
  font-family: var(--sans);
  font-size: 0.64rem;
  text-transform: uppercase;
  letter-spacing: 0.08em;
  color: var(--stone);
  opacity: 0;
  transition: opacity 0.16s;
}
.skill-card:hover .copy-hint { opacity: 1; }

/* ============= COOKBOOK ============= */
.cookbook {
  display: grid;
  gap: 1.4rem;
  margin-top: 1.5rem;
}
.cookbook-cat {
  background: var(--paper-ivory);
  border: 1px solid var(--border-cream);
  border-radius: 4px;
  padding: 1.2rem 1.4rem;
  box-shadow: 0 0 0 1px var(--ring-warm);
}
.cookbook-cat-title {
  font-family: var(--sans);
  font-weight: 600;
  text-transform: uppercase;
  letter-spacing: 0.1em;
  font-size: 0.82rem;
  color: var(--ink-blue);
  margin-bottom: 1rem;
  border-bottom: 1px solid var(--border-soft);
  padding-bottom: 0.4rem;
}
.cookbook-item {
  margin-bottom: 1.2rem;
}
.cookbook-item:last-child { margin-bottom: 0; }
.cookbook-item-title {
  font-family: var(--serif);
  font-weight: 500;
  font-size: 1rem;
  margin-bottom: 0.5rem;
  color: var(--near-black);
}
.cookbook-item pre {
  background: var(--paper-base);
  border: 1px solid var(--border-warm);
  border-left: 3px solid var(--ink-blue);
  padding: 0.9rem 1.1rem;
  border-radius: 3px;
  font-family: var(--mono);
  font-size: 0.82rem;
  color: var(--dark-warm);
  white-space: pre-wrap;
  margin: 0;
  overflow-x: auto;
}
.copy-btn {
  margin-top: 0.5rem;
  background: var(--paper-base);
  border: 1px solid var(--border-warm);
  border-radius: 3px;
  font-family: var(--sans);
  font-size: 0.78rem;
  padding: 0.35rem 0.8rem;
  color: var(--ink-blue);
  cursor: pointer;
}
.copy-btn:hover { border-color: var(--ink-blue-light); background: var(--ink-tint); }

/* ============= CHECKLIST ============= */
.checklist {
  margin: 1.6rem 0;
}
.check-item {
  display: flex;
  gap: 0.8rem;
  align-items: flex-start;
  background: var(--paper-ivory);
  border: 1px solid var(--border-cream);
  border-radius: 4px;
  padding: 0.9rem 1.1rem;
  margin-bottom: 0.6rem;
  cursor: pointer;
  transition: all 0.18s;
}
.check-item:hover { border-color: var(--ink-blue-light); }
.check-item.checked { background: var(--ink-tint); border-color: var(--ink-blue); }
.check-box {
  flex: 0 0 1.2rem;
  height: 1.2rem;
  border: 1.5px solid var(--ring-deep);
  border-radius: 3px;
  margin-top: 0.18rem;
  display: flex;
  align-items: center;
  justify-content: center;
  font-family: var(--sans);
  color: transparent;
  transition: all 0.18s;
}
.check-item.checked .check-box {
  background: var(--ink-blue);
  border-color: var(--ink-blue);
  color: #fff;
}
.check-content {
  flex: 1;
}
.check-q { font-size: 0.98rem; line-height: 1.5; color: var(--near-black); }
.check-why {
  font-size: 0.82rem;
  color: var(--olive);
  margin-top: 0.3rem;
  font-family: var(--sans);
  display: none;
}
.check-item.checked .check-why,
.check-item:hover .check-why { display: block; }

.checklist-cta {
  margin: 1.6rem 0 0.4rem;
  text-align: center;
}
.cta {
  background: var(--ink-blue);
  color: #fff;
  border: none;
  border-radius: 4px;
  padding: 0.8rem 2rem;
  font-family: var(--sans);
  font-weight: 500;
  font-size: 1rem;
  letter-spacing: 0.04em;
  cursor: pointer;
  transition: background 0.18s, opacity 0.18s;
}
.cta:disabled {
  background: var(--ring-deep);
  cursor: not-allowed;
  opacity: 0.6;
}
.cta:not(:disabled):hover { background: var(--ink-blue-light); }
.cta-hint {
  margin-top: 0.6rem;
  font-family: var(--sans);
  font-size: 0.84rem;
  color: var(--olive);
}

/* ============= FOOTER ============= */
.footer {
  background: var(--paper-deep);
  padding: 2rem 1.5rem;
  font-family: var(--sans);
  font-size: 0.82rem;
  color: var(--charcoal);
  border-top: 1px solid var(--border-soft);
}
.footer .container > div { margin-bottom: 0.4rem; }

/* ============= TOAST ============= */
.toast {
  position: fixed;
  bottom: 2rem;
  left: 50%;
  transform: translateX(-50%) translateY(20px);
  background: var(--ink-blue);
  color: #fff;
  padding: 0.5rem 1rem;
  border-radius: 4px;
  font-family: var(--sans);
  font-size: 0.86rem;
  opacity: 0;
  pointer-events: none;
  transition: opacity 0.2s, transform 0.2s;
  z-index: 100;
}
.toast.show { opacity: 1; transform: translateX(-50%) translateY(0); }

/* ============= RESPONSIVE ============= */
@media (max-width: 760px) {
  .hero-title { font-size: 2rem; }
  .comparison { grid-template-columns: 1fr; }
  .vs { display: none; }
  .papers-strip-track { grid-template-columns: repeat(8, 1fr); }
  .nav-links { gap: 0.9rem; font-size: 0.74rem; }
  h2 { font-size: 1.5rem; }
  .terminal-body { font-size: 0.78rem; padding: 1rem; }
  .section { padding: 3.5rem 1.2rem; }
}

/* =============================================================
   Visual refresh with generated illustrations.
   ============================================================= */

:root {
  --paper-base:    #f4f6f4;
  --paper-ivory:   #ffffff;
  --paper-sand:    #e6ecea;
  --paper-deep:    #eef3f4;

  --ink-blue:      #183a5a;
  --ink-blue-light:#227486;
  --ink-tint:      #e3f2f4;

  --near-black:    #111827;
  --dark-warm:     #26313a;
  --charcoal:      #4a5562;
  --olive:         #5b6868;
  --stone:         #7b868d;

  --border-cream:  #dce4e2;
  --border-warm:   #ccd8d5;
  --border-soft:   #dfe7e5;

  --ring-warm:     rgba(24, 58, 90, 0.08);
  --ring-deep:     rgba(24, 58, 90, 0.16);

  --color-gap:        #ba493f;
  --color-gap-bg:     #f8e7e3;
  --color-idea:       #183a5a;
  --color-idea-bg:    #e3f2f4;
  --color-evidence:   #3e7a62;
  --color-evidence-bg:#e7f1eb;
  --color-purple:     #755a95;

  --shadow-soft: 0 18px 48px -28px rgba(17, 24, 39, 0.38);
  --shadow-card: 0 14px 36px -26px rgba(24, 58, 90, 0.45);
}

html, body {
  background:
    linear-gradient(180deg, #f7f8f6 0%, var(--paper-base) 34%, #eef3f4 100%);
  color: var(--near-black);
  font-family: var(--sans);
  line-height: 1.62;
}

body::before {
  content: "";
  position: fixed;
  inset: 0;
  pointer-events: none;
  background-image:
    linear-gradient(rgba(24, 58, 90, 0.035) 1px, transparent 1px),
    linear-gradient(90deg, rgba(24, 58, 90, 0.028) 1px, transparent 1px);
  background-size: 44px 44px;
  mask-image: linear-gradient(to bottom, transparent 0, black 18%, black 74%, transparent 100%);
  z-index: -1;
}

a {
  color: var(--ink-blue-light);
  border-bottom-color: rgba(34, 116, 134, 0.35);
}

strong {
  color: var(--ink-blue);
  font-weight: 650;
}

code {
  background: rgba(24, 58, 90, 0.08);
  border: 1px solid rgba(24, 58, 90, 0.08);
  color: #13344f;
}

.nav {
  background: rgba(255, 255, 255, 0.82);
  border-bottom: 1px solid rgba(24, 58, 90, 0.12);
  box-shadow: 0 12px 34px -30px rgba(17, 24, 39, 0.55);
}

.nav-inner {
  max-width: 1180px;
  padding: 0.78rem 1.4rem;
}

.brand {
  font-family: var(--sans);
  font-size: 0.95rem;
  font-weight: 700;
}

.nav-links {
  gap: 1rem;
  font-size: 0.76rem;
  letter-spacing: 0.08em;
}

.nav-links a {
  padding: 0.28rem 0;
}

.section {
  padding: 6.2rem 1.5rem;
  border-bottom: 1px solid rgba(24, 58, 90, 0.1);
}

.section-alt {
  background: rgba(232, 240, 239, 0.68);
}

.section-terminal {
  background:
    radial-gradient(circle at 18% 8%, rgba(34, 116, 134, 0.12), transparent 30%),
    linear-gradient(180deg, #eef3f4, #e7eeee);
}

.container {
  max-width: 1180px;
}

.container.narrow,
.narrow-block {
  max-width: 780px;
  margin-left: auto;
  margin-right: auto;
}

.eyebrow {
  color: var(--ink-blue-light);
  font-weight: 700;
  letter-spacing: 0.16em;
}

h1, h2, h3 {
  font-family: var(--serif);
  font-weight: 600;
  color: var(--near-black);
}

h2 {
  border-left: 0;
  padding-left: 0;
  font-size: clamp(2rem, 3vw, 3rem);
  margin-bottom: 1rem;
}

h2::after {
  content: "";
  display: block;
  width: 4rem;
  height: 3px;
  margin-top: 0.75rem;
  background: linear-gradient(90deg, var(--ink-blue), var(--ink-blue-light), #3e7a62);
  border-radius: 999px;
}

.lede {
  color: var(--charcoal);
  font-size: 1.04rem;
}

.section-grid {
  display: grid;
  grid-template-columns: minmax(0, 0.98fr) minmax(340px, 0.82fr);
  gap: clamp(1.6rem, 4vw, 4rem);
  align-items: center;
  margin-bottom: 2rem;
}

.section-visual,
.paper-visual {
  margin: 0;
  overflow: hidden;
  border-radius: 8px;
  border: 1px solid rgba(24, 58, 90, 0.14);
  background: var(--paper-ivory);
  box-shadow: var(--shadow-soft);
}

.section-visual img,
.paper-visual img {
  display: block;
  width: 100%;
  height: 100%;
  object-fit: cover;
}

.section-visual {
  aspect-ratio: 16 / 10;
}

.section-visual-wide {
  aspect-ratio: 21 / 8;
  margin: 1.2rem 0 1.8rem;
}

.visual-pair {
  display: grid;
  grid-template-columns: 1.08fr 0.92fr;
  gap: 1rem;
  margin: 1.6rem 0 1.7rem;
}

.visual-pair .section-visual {
  aspect-ratio: 16 / 8.6;
}

/* Hero */
.section-hero {
  position: relative;
  isolation: isolate;
  min-height: calc(100vh - 62px);
  padding-top: 6.2rem;
  padding-bottom: 4.2rem;
  overflow: hidden;
  color: #f8fbfb;
  background: #07131e;
}

.section-hero::before,
.section-hero::after {
  content: "";
  position: absolute;
  inset: 0;
  z-index: -2;
}

.section-hero::before {
  background-image: url("assets/hero-research-workstation.webp");
  background-size: cover;
  background-position: center;
  transform: scale(1.015);
}

.section-hero::after {
  z-index: -1;
  background:
    linear-gradient(90deg, rgba(6, 16, 26, 0.92) 0%, rgba(6, 16, 26, 0.76) 40%, rgba(6, 16, 26, 0.34) 100%),
    linear-gradient(180deg, rgba(6, 16, 26, 0.22), rgba(6, 16, 26, 0.82));
}

.hero-stack {
  position: relative;
}

.hero-copy {
  max-width: 760px;
  padding-top: 1rem;
}

.section-hero .eyebrow {
  color: #8ed3df;
}

.hero-title {
  font-size: clamp(2.35rem, 3.8vw, 3.85rem);
  line-height: 1.14;
  color: #f8fbfb;
  max-width: 980px;
  text-wrap: balance;
  text-shadow: 0 18px 42px rgba(0, 0, 0, 0.36);
}

.hero-sub {
  color: rgba(248, 251, 251, 0.84);
  font-family: var(--sans);
  font-size: 1.08rem;
  max-width: 650px;
}

.comparison {
  max-width: 930px;
  margin-top: 1.7rem;
  gap: 1rem;
}

.card {
  border-radius: 8px;
  background: rgba(255, 255, 255, 0.92);
  border: 1px solid rgba(255, 255, 255, 0.58);
  border-top: 4px solid var(--ink-blue);
  border-left: 1px solid rgba(255, 255, 255, 0.58);
  box-shadow: var(--shadow-card);
  backdrop-filter: blur(14px);
}

.card-red {
  border-top-color: var(--color-gap);
}

.card-blue {
  border-top-color: #2a8796;
}

.card-tag {
  color: var(--olive);
  letter-spacing: 0.08em;
}

.card-num {
  font-family: var(--sans);
  font-weight: 800;
  color: var(--ink-blue);
  margin: 0.45rem 0 0.45rem;
}

.vs {
  color: rgba(255, 255, 255, 0.76);
}

.hero-callout {
  max-width: 790px;
  background: rgba(255, 255, 255, 0.9);
  border: 1px solid rgba(255, 255, 255, 0.58);
  border-left: 4px solid #65c5c4;
  color: var(--near-black);
  border-radius: 8px;
  box-shadow: var(--shadow-card);
  backdrop-filter: blur(14px);
}

.section-hero .hero-callout .dim {
  color: var(--olive);
}

.paper-visual {
  max-width: 920px;
  aspect-ratio: 21 / 7.2;
  margin: 1.55rem 0 1.05rem;
  opacity: 0.96;
}

.papers-strip {
  max-width: 1020px;
}

.papers-strip-label {
  color: rgba(248, 251, 251, 0.72);
}

.paper-tile {
  height: 76px;
  background: rgba(255, 255, 255, 0.9);
  border: 1px solid rgba(255, 255, 255, 0.56);
  border-radius: 6px;
  box-shadow: 0 10px 22px -20px rgba(0, 0, 0, 0.6);
}

.paper-tile:hover {
  box-shadow: 0 12px 28px -18px rgba(50, 195, 200, 0.55);
}

/* Widgets and content blocks */
.bar-widget,
.cookbook-cat,
.skill-card,
.check-item,
.demo-summary {
  border-radius: 8px;
  border: 1px solid rgba(24, 58, 90, 0.12);
  box-shadow: var(--shadow-card);
}

.bar-widget {
  padding: 1.8rem;
}

.bar-track {
  height: 34px;
  border-radius: 7px;
}

.bar-impl {
  background: linear-gradient(90deg, #f5c5bc, #f8ded9);
}

.bar-physics {
  background: linear-gradient(90deg, #b8e3df, #dff3ef);
}

.bar-output {
  background: #f8fbfb;
  border: 1px solid rgba(24, 58, 90, 0.1);
  border-left: 4px solid var(--ink-blue-light);
  border-radius: 8px;
}

.callout {
  border-radius: 8px;
  border: 1px solid rgba(24, 58, 90, 0.12);
  border-left: 4px solid var(--ink-blue-light);
  background: #edf7f7;
}

/* Workflow */
.mini-dashboard {
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: 0.8rem;
  margin: -0.4rem 0 1.2rem;
}

.mini-metric {
  background: rgba(255, 255, 255, 0.88);
  border: 1px solid rgba(24, 58, 90, 0.12);
  border-radius: 8px;
  padding: 1rem 1.1rem;
  box-shadow: var(--shadow-card);
}

.mini-metric span {
  display: block;
  font-family: var(--sans);
  font-size: 0.72rem;
  letter-spacing: 0.12em;
  text-transform: uppercase;
  color: var(--ink-blue-light);
  margin-bottom: 0.35rem;
}

.mini-metric strong {
  color: var(--near-black);
  font-size: 1.08rem;
}

.workflow-board {
  display: grid;
  grid-template-columns: minmax(260px, 0.38fr) minmax(0, 1fr);
  gap: 1rem;
  align-items: start;
}

.workflow-rail {
  display: grid;
  gap: 0.65rem;
}

.workflow-step {
  display: grid;
  grid-template-columns: 2.2rem 1fr;
  gap: 0.6rem 0.75rem;
  align-items: center;
  text-align: left;
  min-height: 78px;
  background: rgba(255, 255, 255, 0.78);
  border: 1px solid rgba(24, 58, 90, 0.12);
  border-radius: 8px;
  padding: 0.75rem;
  cursor: pointer;
  color: var(--near-black);
  box-shadow: 0 10px 28px -26px rgba(17, 24, 39, 0.5);
}

.workflow-step:hover,
.workflow-step.active {
  border-color: rgba(29, 120, 140, 0.5);
  background: #ffffff;
}

.workflow-phase {
  width: 2.15rem;
  height: 2.15rem;
  display: inline-flex;
  align-items: center;
  justify-content: center;
  background: #e3f2f4;
  color: var(--ink-blue);
  border-radius: 8px;
  font-family: var(--mono);
  font-weight: 700;
  font-size: 0.9rem;
  grid-row: span 2;
}

.workflow-phase.big {
  width: 3rem;
  height: 3rem;
  font-size: 1.15rem;
}

.workflow-step-title {
  font-weight: 750;
  font-size: 0.96rem;
}

.workflow-step-meta {
  color: var(--olive);
  font-size: 0.78rem;
}

.workflow-detail {
  min-height: 560px;
  background: rgba(255, 255, 255, 0.92);
  border: 1px solid rgba(24, 58, 90, 0.12);
  border-radius: 8px;
  padding: 1.4rem;
  box-shadow: var(--shadow-card);
}

.workflow-detail-head {
  display: flex;
  gap: 1rem;
  align-items: center;
  margin-bottom: 0.9rem;
}

.workflow-detail h3,
.failure-detail h3,
.session-card h3,
.launch-brief h3 {
  margin: 0;
  font-family: var(--serif);
  font-size: 1.35rem;
  line-height: 1.2;
}

.workflow-chips {
  display: flex;
  gap: 0.45rem;
  flex-wrap: wrap;
  margin-top: 0.45rem;
}

.workflow-chips span,
.session-meta {
  background: #edf3f2;
  border: 1px solid rgba(24, 58, 90, 0.08);
  border-radius: 7px;
  padding: 0.22rem 0.55rem;
  color: var(--olive);
  font-size: 0.76rem;
}

.workflow-aim {
  color: var(--charcoal);
  margin: 0 0 0.9rem;
}

.workflow-list {
  margin: 0 0 1rem;
  padding-left: 1.25rem;
  color: var(--dark-warm);
}

.workflow-list li {
  margin: 0.45rem 0;
}

.workflow-checkpoint {
  display: grid;
  gap: 0.35rem;
  background: #f8e7e3;
  border-left: 4px solid var(--color-gap);
  border-radius: 8px;
  padding: 0.9rem 1rem;
  color: var(--dark-warm);
  margin: 1rem 0;
}

.workflow-checkpoint b {
  color: var(--color-gap);
  font-family: var(--sans);
  text-transform: uppercase;
  font-size: 0.72rem;
  letter-spacing: 0.12em;
}

.workflow-prompt,
.failure-prompt,
.launch-brief pre,
.production-brief pre {
  background: #0d1720;
  color: #e7f1ef;
  border: 1px solid rgba(24, 58, 90, 0.2);
  border-left: 4px solid #2b95a6;
  border-radius: 8px;
  padding: 1rem;
  white-space: pre-wrap;
  overflow-x: auto;
  font-size: 0.82rem;
  line-height: 1.58;
}

/* Validation */
.validation-grid {
  display: grid;
  grid-template-columns: repeat(4, minmax(0, 1fr));
  gap: 1rem;
}

.validation-card,
.production-card,
.paperflow-card {
  background: rgba(255, 255, 255, 0.94);
  border: 1px solid rgba(24, 58, 90, 0.12);
  border-radius: 8px;
  padding: 1.15rem;
  box-shadow: var(--shadow-card);
}

.validation-card {
  display: flex;
  flex-direction: column;
  min-height: 330px;
}

.validation-tag,
.paperflow-tag {
  align-self: flex-start;
  background: #e3f2f4;
  border: 1px solid rgba(29, 120, 140, 0.14);
  border-radius: 7px;
  color: var(--ink-blue-light);
  font-family: var(--sans);
  font-size: 0.72rem;
  letter-spacing: 0.1em;
  text-transform: uppercase;
  padding: 0.24rem 0.55rem;
  margin-bottom: 0.8rem;
}

.validation-card h3,
.production-card h3,
.paperflow-card h3 {
  margin: 0 0 0.65rem;
  font-size: 1.18rem;
}

.validation-card p,
.production-card p,
.paperflow-card p {
  color: var(--charcoal);
  margin: 0 0 0.9rem;
}

.validation-row,
.production-row {
  display: grid;
  gap: 0.25rem;
  padding: 0.65rem 0;
  border-top: 1px solid rgba(24, 58, 90, 0.08);
  font-size: 0.9rem;
}

.validation-row b,
.production-row b {
  color: var(--ink-blue-light);
  font-size: 0.72rem;
  letter-spacing: 0.1em;
  text-transform: uppercase;
}

.validation-card .copy-btn {
  margin-top: auto;
}

/* Production */
.production-grid {
  display: grid;
  grid-template-columns: repeat(5, minmax(0, 1fr));
  gap: 0.85rem;
  margin-bottom: 1rem;
}

.production-card {
  position: relative;
  min-height: 300px;
  padding-top: 3.7rem;
}

.production-index {
  position: absolute;
  top: 1rem;
  left: 1rem;
  width: 2.2rem;
  height: 2.2rem;
  display: inline-flex;
  align-items: center;
  justify-content: center;
  background: #e3f2f4;
  color: var(--ink-blue);
  border-radius: 8px;
  font-family: var(--mono);
  font-weight: 700;
}

.production-danger {
  margin-top: 0.75rem;
  background: #f8e7e3;
  border-left: 4px solid var(--color-gap);
  border-radius: 8px;
  padding: 0.72rem 0.8rem;
  color: var(--dark-warm);
  font-size: 0.88rem;
}

.production-brief {
  background: rgba(255, 255, 255, 0.94);
  border: 1px solid rgba(24, 58, 90, 0.12);
  border-radius: 8px;
  padding: 1.2rem;
  box-shadow: var(--shadow-card);
}

/* Paper pipeline */
.paperflow-grid {
  display: grid;
  grid-template-columns: repeat(4, minmax(0, 1fr));
  gap: 1rem;
}

.paperflow-card {
  min-height: 300px;
  display: flex;
  flex-direction: column;
}

.paperflow-proof {
  background: #edf7f7;
  border-left: 4px solid var(--ink-blue-light);
  border-radius: 8px;
  padding: 0.8rem;
  color: var(--dark-warm);
  font-size: 0.9rem;
  margin: 0.4rem 0 0.9rem;
}

.paperflow-proof b {
  display: block;
  color: var(--ink-blue-light);
  font-size: 0.72rem;
  letter-spacing: 0.1em;
  text-transform: uppercase;
  margin-bottom: 0.25rem;
}

.paperflow-card .copy-btn {
  margin-top: auto;
}

/* Paradigm explainer */
.paradigm-comparison {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 1rem;
  margin: 1.4rem 0 2.6rem;
}

.paradigm-card,
.principle-card {
  background: rgba(255, 255, 255, 0.94);
  border: 1px solid rgba(24, 58, 90, 0.12);
  border-radius: 8px;
  box-shadow: var(--shadow-card);
  overflow: hidden;
}

.paradigm-card img {
  display: block;
  width: 100%;
  aspect-ratio: 16 / 8.6;
  object-fit: cover;
  border-bottom: 1px solid rgba(24, 58, 90, 0.1);
}

.paradigm-card-body {
  padding: 1.2rem;
}

.paradigm-card h3,
.principle-card h3 {
  margin: 0 0 0.6rem;
  font-size: 1.35rem;
}

.paradigm-card p,
.principle-card p {
  color: var(--charcoal);
  margin: 0 0 0.9rem;
}

.paradigm-card ul {
  margin: 0;
  padding-left: 1.1rem;
  color: var(--dark-warm);
}

.paradigm-card li {
  margin: 0.42rem 0;
}

.paradigm-definition {
  margin-top: 1.2rem;
}

.principle-grid {
  display: grid;
  grid-template-columns: repeat(4, minmax(0, 1fr));
  gap: 1rem;
  margin-top: 1.2rem;
}

.principle-card {
  padding: 1.1rem;
}

.principle-card span {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  width: 2.3rem;
  height: 2.3rem;
  margin-bottom: 0.9rem;
  background: #e3f2f4;
  color: var(--ink-blue);
  border-radius: 8px;
  font-family: var(--mono);
  font-weight: 700;
}

/* Tool comparison */
.tool-compare {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 1rem;
  margin: 1.4rem 0 1.4rem;
}

.tool-card {
  position: relative;
  background: rgba(255, 255, 255, 0.94);
  border: 1px solid rgba(24, 58, 90, 0.12);
  border-radius: 8px;
  padding: 1.2rem;
  box-shadow: var(--shadow-card);
  overflow: hidden;
}

.tool-card::before {
  content: "";
  position: absolute;
  inset: 0 0 auto;
  height: 4px;
  background: linear-gradient(90deg, var(--ink-blue), var(--ink-blue-light));
}

.tool-card-claude::before {
  background: linear-gradient(90deg, #a8453e, #e3a092);
}

.tool-label {
  display: inline-flex;
  align-items: center;
  height: 1.7rem;
  padding: 0 0.62rem;
  margin-bottom: 0.8rem;
  border-radius: 7px;
  background: #e3f2f4;
  color: var(--ink-blue-light);
  font-family: var(--sans);
  font-size: 0.72rem;
  font-weight: 700;
  letter-spacing: 0.1em;
  text-transform: uppercase;
}

.tool-card-claude .tool-label {
  background: #f8e7e3;
  color: #a8453e;
}

.tool-card h3 {
  margin: 0 0 0.65rem;
  font-size: 1.32rem;
}

.tool-card p {
  margin: 0 0 0.85rem;
  color: var(--charcoal);
}

.tool-card ul {
  margin: 0;
  padding-left: 1.1rem;
  color: var(--dark-warm);
}

.tool-card li {
  margin: 0.45rem 0;
}

.decision-table {
  margin: 1.2rem 0 1.4rem;
  border: 1px solid rgba(24, 58, 90, 0.12);
  border-radius: 8px;
  overflow: hidden;
  background: rgba(255, 255, 255, 0.9);
  box-shadow: var(--shadow-card);
}

.decision-row {
  display: grid;
  grid-template-columns: minmax(0, 1.2fr) minmax(180px, 0.62fr) minmax(0, 1.25fr);
  gap: 1rem;
  align-items: start;
  padding: 0.92rem 1rem;
  border-top: 1px solid rgba(24, 58, 90, 0.08);
  color: var(--dark-warm);
}

.decision-row:first-child {
  border-top: 0;
}

.decision-head {
  background: #0f3554;
  color: #f8fbfb;
  font-family: var(--sans);
  font-size: 0.76rem;
  font-weight: 700;
  letter-spacing: 0.1em;
  text-transform: uppercase;
}

.decision-row:not(.decision-head) span:nth-child(2) {
  color: var(--ink-blue);
  font-weight: 750;
}

/* Failure modes */
.failure-panel {
  display: grid;
  grid-template-columns: minmax(250px, 0.34fr) minmax(0, 1fr);
  gap: 1rem;
}

.failure-tabs {
  display: grid;
  gap: 0.65rem;
}

.failure-tab {
  min-height: 68px;
  text-align: left;
  border: 1px solid rgba(24, 58, 90, 0.12);
  border-radius: 8px;
  background: rgba(255, 255, 255, 0.82);
  padding: 0.8rem;
  cursor: pointer;
  color: var(--near-black);
}

.failure-tab:hover,
.failure-tab.active {
  background: #ffffff;
  border-color: rgba(186, 73, 63, 0.5);
}

.failure-tab-title {
  display: block;
  font-weight: 750;
}

.failure-tab-badge {
  display: block;
  margin-top: 0.25rem;
  color: var(--olive);
  font-size: 0.76rem;
}

.failure-detail {
  background: rgba(255, 255, 255, 0.94);
  border: 1px solid rgba(24, 58, 90, 0.12);
  border-radius: 8px;
  padding: 1.4rem;
  box-shadow: var(--shadow-card);
}

.failure-detail-head,
.launch-head {
  display: flex;
  justify-content: space-between;
  gap: 1rem;
  align-items: flex-start;
  margin-bottom: 1rem;
}

.failure-row {
  display: grid;
  grid-template-columns: 4rem minmax(0, 1fr);
  gap: 0.8rem;
  padding: 0.85rem 0;
  border-top: 1px solid rgba(24, 58, 90, 0.08);
}

.failure-row b {
  color: var(--ink-blue-light);
  font-family: var(--sans);
  font-size: 0.78rem;
  letter-spacing: 0.08em;
  text-transform: uppercase;
}

.failure-row p {
  margin: 0;
  color: var(--dark-warm);
}

/* Session protocol */
.session-grid {
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: 1rem;
  margin-bottom: 1.2rem;
}

.session-card,
.launch-brief {
  background: rgba(255, 255, 255, 0.92);
  border: 1px solid rgba(24, 58, 90, 0.12);
  border-radius: 8px;
  padding: 1.2rem;
  box-shadow: var(--shadow-card);
}

.session-index {
  width: 2.2rem;
  height: 2.2rem;
  display: inline-flex;
  align-items: center;
  justify-content: center;
  background: #e3f2f4;
  color: var(--ink-blue);
  border-radius: 8px;
  font-family: var(--mono);
  font-weight: 700;
  margin-bottom: 0.8rem;
}

.session-card p {
  color: var(--charcoal);
  margin: 0.8rem 0;
}

.session-card ul {
  padding-left: 1.1rem;
  margin: 0.8rem 0 0;
}

.session-card li {
  margin: 0.45rem 0;
  color: var(--dark-warm);
}

/* Terminal */
.demo-tabs {
  gap: 0.7rem;
}

.demo-tab {
  border-radius: 8px;
  background: rgba(255, 255, 255, 0.86);
  box-shadow: 0 10px 28px -26px rgba(17, 24, 39, 0.5);
}

.demo-tab.active {
  background: linear-gradient(135deg, var(--ink-blue), #206f82);
}

.terminal-shell {
  border-radius: 8px;
  border: 1px solid rgba(6, 16, 26, 0.35);
  box-shadow: 0 32px 72px -34px rgba(6, 16, 26, 0.72);
}

.terminal-titlebar,
.terminal-controls {
  background: #17212c;
}

.terminal-body {
  background:
    radial-gradient(circle at 80% 0%, rgba(89, 213, 221, 0.06), transparent 34%),
    #0c1218;
}

.t-thinking {
  font-style: normal;
}

.t-note {
  font-style: normal;
  color: #aab4b5;
}

.t-filter {
  border-radius: 8px;
  box-shadow: 0 18px 40px -28px rgba(0, 0, 0, 0.7);
}

.ctrl,
.ctrl-speed select {
  border-radius: 7px;
}

.ctrl-primary {
  background: #1d788c;
  border-color: #1d788c;
}

.demo-summary {
  background: #ffffff;
}

/* Skills and prompts */
.stage-tab {
  border-radius: 7px;
  background: rgba(255, 255, 255, 0.68);
}

.stage-tab.active {
  background: #1d788c;
  border-color: #1d788c;
}

.skill-card {
  border-left-width: 0;
  border-top: 4px solid var(--ink-blue);
  min-height: 210px;
}

.skill-card.color-blue { border-top-color: var(--ink-blue); }
.skill-card.color-red { border-top-color: var(--color-gap); }
.skill-card.color-green { border-top-color: var(--color-evidence); }
.skill-card.color-purple { border-top-color: var(--color-purple); }

.skill-invoke {
  background: #edf3f2;
  border: 1px solid rgba(24, 58, 90, 0.09);
}

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

.cookbook-cat {
  padding: 1.3rem;
}

.cookbook-item pre {
  border-radius: 8px;
  border-left: 4px solid var(--ink-blue-light);
  background: #f8fbfb;
}

.copy-btn {
  border-radius: 7px;
}

/* Checklist */
.check-item {
  background: rgba(255, 255, 255, 0.92);
  align-items: stretch;
}

.check-item.checked {
  background: #e7f4f2;
  border-color: rgba(29, 120, 140, 0.45);
}

.check-box {
  border-radius: 6px;
}

.cta {
  border-radius: 8px;
  background: linear-gradient(135deg, var(--ink-blue), #1d788c);
}

.cta:not(:disabled):hover {
  background: linear-gradient(135deg, #102c45, #176477);
}

.disclaimer {
  border-radius: 8px;
}

.footer {
  background: #e8eeee;
}

.toast {
  border-radius: 8px;
  box-shadow: 0 18px 42px -22px rgba(6, 16, 26, 0.65);
}

@media (max-width: 920px) {
  .section-grid,
  .visual-pair,
  .cookbook,
  .workflow-board,
  .failure-panel,
  .session-grid,
  .validation-grid,
  .production-grid,
  .paperflow-grid,
  .paradigm-comparison,
  .principle-grid,
  .tool-compare {
    grid-template-columns: 1fr;
  }

  .section-visual-wide,
  .visual-pair .section-visual {
    aspect-ratio: 16 / 9;
  }

  .section-hero {
    min-height: auto;
  }

  .workflow-detail {
    min-height: auto;
  }

  .workflow-rail,
  .failure-tabs {
    grid-template-columns: repeat(2, minmax(0, 1fr));
  }

  .mini-dashboard {
    grid-template-columns: 1fr;
  }
}

@media (max-width: 760px) {
  .section {
    padding: 4rem 1rem;
  }

  .section-hero {
    padding-top: 4.8rem;
  }

  .section-hero::before {
    background-position: 58% center;
  }

  .section-hero::after {
    background:
      linear-gradient(90deg, rgba(6, 16, 26, 0.94), rgba(6, 16, 26, 0.68)),
      linear-gradient(180deg, rgba(6, 16, 26, 0.3), rgba(6, 16, 26, 0.9));
  }

  .hero-title {
    font-size: clamp(2.35rem, 14vw, 3.3rem);
  }

  .hero-sub {
    font-size: 1rem;
  }

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

  .vs {
    display: none;
  }

  .card-num {
    font-size: 3.5rem;
  }

  .paper-visual {
    aspect-ratio: 16 / 8.5;
  }

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

  .paper-tile {
    height: 84px;
  }

  .nav-inner {
    align-items: flex-start;
  }

  .nav-links {
    width: 100%;
    overflow-x: auto;
    padding-bottom: 0.1rem;
    flex-wrap: nowrap;
    gap: 0.75rem;
    font-size: 0.7rem;
  }

  .nav-links a {
    flex: 0 0 auto;
    letter-spacing: 0.04em;
  }

  h2 {
    font-size: 1.95rem;
  }

  .bar-labels {
    display: grid;
    gap: 0.45rem;
  }

  .terminal-body {
    min-height: 420px;
    max-height: 560px;
  }

  .workflow-rail,
  .failure-tabs {
    grid-template-columns: 1fr;
  }

  .workflow-detail,
  .failure-detail,
  .session-card,
  .launch-brief,
  .production-brief,
  .validation-card,
  .production-card,
  .paperflow-card,
  .paradigm-card-body,
  .principle-card,
  .tool-card {
    padding: 1rem;
  }

  .decision-row {
    grid-template-columns: 1fr;
    gap: 0.35rem;
  }

  .decision-head {
    display: none;
  }

  .failure-detail-head,
  .launch-head {
    display: grid;
  }

  .failure-row {
    grid-template-columns: 1fr;
    gap: 0.25rem;
  }

  .production-card {
    min-height: auto;
    padding-top: 3.6rem;
  }

  .validation-card,
  .paperflow-card {
    min-height: auto;
  }
}