/* =========================================================================
   2026 Agentic Coding Trends · composite
   Claude brand editorial skin layered on the MD3 token system.
   Pure CSS, no preprocessor, no build step.

   The palette mirrors Anthropic's report: warm ivory ground, terracotta /
   clay accent, near-black serif display headings, and four section accents
   (green / blue / purple / pink) echoing the report's category divider pages.
   ========================================================================= */

/* ---- Tokens : LIGHT (default) — warm ivory + terracotta ---- */
:root,
[data-theme="light"] {
  --primary:               #BE5B3A;   /* clay / terracotta */
  --on-primary:            #FFFFFF;
  --primary-container:     #F4DACD;
  --on-primary-container:  #561F0C;
  --secondary:             #6E655A;
  --secondary-container:   #E9E0D2;
  --on-secondary-container:#2A251E;
  --tertiary:              #9A6A4D;
  --tertiary-container:    #F2D9C8;

  --background:            #F3EEE6;   /* Anthropic-ivory ground */
  --on-background:         #201E1A;
  --surface:               #F3EEE6;
  --surface-container:     #FBF8F2;   /* card "paper", lifts off the ground */
  --surface-container-high:#FFFFFF;
  --surface-variant:       #E8E0D2;
  --on-surface:            #201E1A;
  --on-surface-variant:    #5A5249;

  --outline:               #9A9085;
  --outline-variant:       #DCD3C4;
  --error:                 #B3261E;
  --shadow:                rgba(60,42,28,.16);

  /* section accents (echo the report's divider pages) */
  --accent-green:  #5F7A48;
  --accent-blue:   #3F6CA0;
  --accent-purple: #6E5C9C;
  --accent-pink:   #B86C7C;

  --elev-1: 0 1px 2px rgba(60,42,28,.08), 0 1px 3px 1px rgba(60,42,28,.05);
  --elev-2: 0 2px 8px 2px rgba(60,42,28,.09), 0 1px 2px rgba(60,42,28,.10);
  --elev-3: 0 8px 24px 4px rgba(60,42,28,.16), 0 2px 6px rgba(60,42,28,.12);

  --radius-sm: 8px;
  --radius:    16px;
  --radius-lg: 26px;

  --font-serif: "Newsreader", "Noto Serif TC", Georgia, "Times New Roman", serif;
  --font-body:  "Hanken Grotesk", "Noto Sans TC", system-ui, -apple-system, "Segoe UI", sans-serif;
}

/* ---- Tokens : DARK — warm near-black ---- */
[data-theme="dark"] {
  --primary:               #E89A7C;
  --on-primary:            #4A1B0A;
  --primary-container:     #6E3B27;
  --on-primary-container:  #F4DACD;
  --secondary:             #CFC3B2;
  --secondary-container:   #4A4339;
  --on-secondary-container:#EDE3D4;
  --tertiary:              #E0B49B;
  --tertiary-container:    #5A3A28;

  --background:            #1A1714;
  --on-background:         #ECE5DA;
  --surface:               #1A1714;
  --surface-container:     #241F1A;
  --surface-container-high:#2E2823;
  --surface-variant:       #3A332B;
  --on-surface:            #ECE5DA;
  --on-surface-variant:    #C4BAAC;

  --outline:               #8A8073;
  --outline-variant:       #3E372F;
  --error:                 #F2B8B5;
  --shadow:                rgba(0,0,0,.45);

  --accent-green:  #9CB67E;
  --accent-blue:   #82A9DA;
  --accent-purple: #B5A2E2;
  --accent-pink:   #E3A4B1;
}

/* ---- per-section accent (set by app.js from sec.accent) ---- */
[data-accent="green"]  { --section-accent: var(--accent-green);  }
[data-accent="blue"]   { --section-accent: var(--accent-blue);   }
[data-accent="purple"] { --section-accent: var(--accent-purple); }
[data-accent="pink"]   { --section-accent: var(--accent-pink);   }

/* ---- Reset / base ---- */
* { box-sizing: border-box; }
html { scroll-behavior: smooth; }
body {
  margin: 0;
  font-family: var(--font-body);
  background: var(--background);
  color: var(--on-background);
  -webkit-font-smoothing: antialiased;
  text-rendering: optimizeLegibility;
  transition: background .2s, color .2s;
  overflow-x: hidden;
}
a { color: inherit; text-decoration: none; }
.material-symbols-rounded {
  font-variation-settings: "FILL" 0, "wght" 400, "GRAD" 0, "opsz" 24;
  line-height: 1;
  user-select: none;
}

/* ---- App bar ---- */
.appbar {
  position: sticky;
  top: 0;
  z-index: 30;
  background: color-mix(in srgb, var(--background) 85%, transparent);
  backdrop-filter: saturate(150%) blur(10px);
  border-bottom: 1px solid var(--outline-variant);
}
.appbar__inner {
  max-width: 1120px;
  margin: 0 auto;
  padding: 12px 20px;
  display: flex;
  align-items: center;
  gap: 12px;
}
.brand {
  display: flex;
  align-items: center;
  gap: 9px;
  font-family: var(--font-serif);
  font-weight: 600;
  font-size: 1.18rem;
  letter-spacing: -.01em;
  color: var(--on-surface);
  min-width: 0;
  overflow: hidden;
}
.brand__logo { color: var(--primary); flex: 0 0 auto; }
.brand__name { overflow: hidden; text-overflow: ellipsis; white-space: nowrap; }
.appbar__actions { margin-left: auto; display: flex; align-items: center; gap: 6px; flex: 0 0 auto; }

/* ---- Icon button ---- */
.icon-btn {
  display: inline-flex;
  align-items: center;
  gap: 4px;
  border: none;
  background: transparent;
  color: var(--on-surface-variant);
  border-radius: var(--radius-lg);
  padding: 8px 11px;
  cursor: pointer;
  font: inherit;
  transition: background .15s, color .15s;
}
.icon-btn:hover { background: var(--surface-container-high); color: var(--on-surface); }
.icon-btn__txt { font-size: .85rem; font-weight: 600; }

/* ---- Sticky section nav (scrollspy) ---- */
.sectionnav {
  position: sticky;
  top: 57px;
  z-index: 25;
  background: color-mix(in srgb, var(--background) 90%, transparent);
  backdrop-filter: saturate(160%) blur(8px);
  border-bottom: 1px solid var(--outline-variant);
}
.sectionnav__inner {
  max-width: 1120px;
  margin: 0 auto;
  padding: 9px 16px;
  display: flex;
  gap: 8px;
  overflow-x: auto;
  scrollbar-width: none;
}
.sectionnav__inner::-webkit-scrollbar { display: none; }
.navpill {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  flex: 0 0 auto;
  padding: 7px 14px;
  border-radius: var(--radius-lg);
  font-size: .82rem;
  font-weight: 600;
  color: var(--on-surface-variant);
  border: 1px solid var(--outline-variant);
  background: transparent;
  white-space: nowrap;
  cursor: pointer;
  transition: background .15s, color .15s, border-color .15s;
}
.navpill .material-symbols-rounded { font-size: 18px; }
.navpill:hover { background: var(--surface-container-high); color: var(--on-surface); }
.navpill--active {
  background: var(--on-surface);
  color: var(--surface);
  border-color: transparent;
}

/* ---- Section scaffolding ---- */
.section {
  max-width: 1120px;
  margin: 0 auto;
  padding: 64px 20px 16px;
  scroll-margin-top: 116px;
}
.section-head { margin-bottom: 22px; }
.section-head h2 {
  position: relative;
  margin: 0 0 8px;
  padding-top: 16px;
  font-family: var(--font-serif);
  font-size: clamp(1.5rem, 3vw, 1.95rem);
  font-weight: 500;
  letter-spacing: -.015em;
  line-height: 1.18;
  color: var(--on-surface);
}
.section-head h2::before {
  content: "";
  position: absolute;
  top: 0; left: 0;
  width: 38px; height: 3px;
  border-radius: 2px;
  background: var(--section-accent, var(--primary));
}
.section-head__sub {
  margin: 0;
  max-width: 64ch;
  font-size: 1rem;
  line-height: 1.6;
  color: var(--on-surface-variant);
}

/* ---- HERO ---- */
.section--hero { padding-top: 52px; }
.section--hero .section-head h2 {
  padding-top: 0;
  font-size: clamp(2.1rem, 5.6vw, 3.1rem);
  line-height: 1.04;
  letter-spacing: -.025em;
  color: var(--on-background);
}
.section--hero .section-head h2::before { display: none; }
.section--hero .section-head__sub { font-size: 1.08rem; max-width: 70ch; margin-top: 6px; }
.hero__stats {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(150px, 1fr));
  gap: 14px;
  margin-top: 28px;
}
.hero__stat {
  background: var(--surface-container);
  border-radius: var(--radius);
  padding: 22px 20px;
  display: flex;
  flex-direction: column;
  gap: 6px;
  border: 1px solid var(--outline-variant);
}
.hero__stat-value {
  display: inline-flex;
  align-items: baseline;
  gap: 1px;
  font-family: var(--font-serif);
  font-size: 2.4rem;
  font-weight: 500;
  color: var(--section-accent, var(--primary));
  font-variant-numeric: tabular-nums;
  line-height: 1.05;
}
.hero__stat-affix { font-size: 1.5rem; font-weight: 500; }
.hero__stat-label { font-size: .86rem; line-height: 1.4; color: var(--on-surface-variant); }

/* ---- Filter chips ---- */
.chips { display: flex; flex-wrap: wrap; gap: 8px; margin: 0 0 22px; }
.chip {
  font: inherit;
  font-size: .82rem;
  font-weight: 600;
  padding: 7px 16px;
  border-radius: var(--radius-lg);
  cursor: pointer;
  background: transparent;
  color: var(--on-surface-variant);
  border: 1px solid var(--outline-variant);
  transition: background .15s, color .15s, border-color .15s;
}
.chip:hover { background: var(--surface-container-high); color: var(--on-surface); }
.chip--active { color: var(--surface); border-color: transparent; }
.chip--all.chip--active        { background: var(--on-surface); }
.chip--foundation.chip--active { background: var(--accent-green); }
.chip--capability.chip--active { background: var(--accent-blue); }
.chip--impact.chip--active     { background: var(--accent-purple); }

/* ---- CARDS grid ---- */
.grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(280px, 1fr));
  gap: 18px;
}
.card {
  background: var(--surface-container);
  border-radius: var(--radius);
  padding: 22px;
  cursor: pointer;
  border: 1px solid var(--outline-variant);
  transition: box-shadow .18s, transform .18s, border-color .18s;
  display: flex;
  flex-direction: column;
  gap: 10px;
}
/* `.card{display:flex}` would otherwise override the UA [hidden] rule, so the
   category filter could never hide a card. Re-assert hide at higher specificity. */
.card[hidden] { display: none; }
.card:hover,
.card:focus-visible {
  box-shadow: var(--elev-2);
  transform: translateY(-3px);
  border-color: color-mix(in srgb, var(--primary) 40%, var(--outline-variant));
  outline: none;
}
.card__badges { display: flex; flex-wrap: wrap; gap: 6px; }
.card__badge {
  --c: var(--accent-purple);
  font-size: .66rem;
  font-weight: 700;
  letter-spacing: .09em;
  text-transform: uppercase;
  padding: 4px 10px;
  border-radius: 999px;
  color: var(--c);
  background: color-mix(in srgb, var(--c) 14%, var(--surface-container-high));
  border: 1px solid color-mix(in srgb, var(--c) 30%, transparent);
}
.badge--foundation { --c: var(--accent-green); }
.badge--capability { --c: var(--accent-blue); }
.badge--impact     { --c: var(--accent-purple); }
.card__title {
  margin: 0;
  font-size: 1.08rem;
  font-weight: 600;
  line-height: 1.32;
  color: var(--on-surface);
}
.card__summary {
  margin: 0;
  font-size: .92rem;
  line-height: 1.55;
  color: var(--on-surface-variant);
}
.card__tags { margin-top: auto; display: flex; flex-wrap: wrap; gap: 6px; padding-top: 4px; }
.tag {
  font-size: .72rem;
  color: var(--on-surface-variant);
  background: var(--surface-variant);
  padding: 3px 9px;
  border-radius: var(--radius-sm);
}

/* ---- TIMELINE ---- */
.timeline { list-style: none; margin: 0; padding: 0; position: relative; }
.timeline::before {
  content: "";
  position: absolute;
  left: 7px; top: 6px; bottom: 6px;
  width: 2px;
  background: var(--outline-variant);
}
.tl-item { position: relative; padding: 0 0 22px 38px; }
.tl-item:last-child { padding-bottom: 0; }
.tl-dot {
  position: absolute;
  left: 0; top: 6px;
  width: 16px; height: 16px;
  border-radius: 50%;
  background: var(--section-accent, var(--primary));
  border: 3px solid var(--background);
  box-shadow: 0 0 0 2px var(--section-accent, var(--primary));
}
.tl-card {
  background: var(--surface-container);
  border-radius: var(--radius);
  padding: 16px 20px;
  border: 1px solid var(--outline-variant);
}
.tl-date {
  font-size: .76rem;
  font-weight: 700;
  letter-spacing: .05em;
  text-transform: uppercase;
  color: var(--section-accent, var(--primary));
}
.tl-title { margin: 5px 0 7px; font-size: 1.1rem; font-weight: 600; color: var(--on-surface); }
.tl-body { margin: 0; font-size: .92rem; line-height: 1.6; color: var(--on-surface-variant); }

/* ---- BARS (inline SVG) ---- */
.chart-card {
  margin: 0;
  background: var(--surface-container);
  border-radius: var(--radius);
  padding: 24px;
  border: 1px solid var(--outline-variant);
}
.chart-wrap { width: 100%; }
.chart-wrap svg { width: 100%; height: auto; display: block; }
.bar-rect { fill: var(--section-accent, var(--primary)); transition: opacity .15s; }
.bar-rect:hover { opacity: .82; }
.bar-value { fill: var(--on-surface); font-size: 13px; font-weight: 700; font-family: var(--font-body); }
.bar-label { fill: var(--on-surface-variant); font-size: 12px; font-family: var(--font-body); }
.axis-line { stroke: var(--outline-variant); stroke-width: 1.5; }

/* ---- ACCORDION (unused here, kept for completeness) ---- */
.accordion { display: flex; flex-direction: column; gap: 10px; }
.acc-item {
  background: var(--surface-container);
  border-radius: var(--radius);
  border: 1px solid var(--outline-variant);
  overflow: hidden;
}
.acc-q {
  display: flex; align-items: center; justify-content: space-between; gap: 12px;
  padding: 16px 18px; cursor: pointer; font-weight: 600; color: var(--on-surface); list-style: none;
}
.acc-q::-webkit-details-marker { display: none; }
.acc-chevron { transition: transform .2s; color: var(--on-surface-variant); }
.acc-item[open] .acc-chevron { transform: rotate(180deg); }
.acc-a { padding: 0 18px 18px; font-size: .92rem; line-height: 1.6; color: var(--on-surface-variant); }

/* ---- QUOTES ---- */
.quotes-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(260px, 1fr));
  gap: 18px;
}
.quote-card {
  margin: 0;
  position: relative;
  background: var(--surface-container);
  border-radius: var(--radius);
  padding: 26px 24px 20px;
  border: 1px solid var(--outline-variant);
  border-left: 3px solid var(--section-accent, var(--primary));
}
.quote-mark { font-size: 32px; color: var(--section-accent, var(--primary)); opacity: .7; }
.quote-card blockquote {
  margin: 4px 0 14px;
  font-family: var(--font-serif);
  font-size: 1.16rem;
  font-weight: 400;
  line-height: 1.5;
  color: var(--on-surface);
}
.quote-by { font-size: .85rem; font-weight: 600; color: var(--on-surface-variant); }

/* ---- PROSE ---- */
.prose { max-width: 70ch; color: var(--on-surface-variant); font-size: 1.02rem; }
.prose h3 {
  font-family: var(--font-serif);
  color: var(--on-surface);
  font-size: 1.3rem;
  font-weight: 500;
  margin: 26px 0 10px;
}
.prose p { line-height: 1.75; margin: 0 0 16px; }
.prose ul { margin: 0 0 16px; padding-left: 22px; line-height: 1.7; }
.prose li { margin-bottom: 8px; }
.prose li::marker { color: var(--section-accent, var(--primary)); }

/* ---- CTA ---- */
.section--cta { padding-bottom: 28px; }
.cta-card {
  background: linear-gradient(135deg, var(--primary), color-mix(in srgb, var(--primary) 55%, var(--accent-pink)));
  border-radius: var(--radius-lg);
  padding: 48px 32px;
  text-align: center;
  color: #fff;
}
.cta-card h2 { margin: 0 0 10px; font-family: var(--font-serif); font-weight: 500; font-size: 1.9rem; color: #fff; }
.cta-card p { margin: 0 auto 24px; max-width: 54ch; color: rgba(255,255,255,.92); line-height: 1.6; }
.cta-btn {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  background: #fff;
  color: var(--primary);
  padding: 13px 26px;
  border-radius: var(--radius-lg);
  font-weight: 700;
  box-shadow: var(--elev-1);
  transition: box-shadow .15s, transform .15s;
}
.cta-btn:hover { box-shadow: var(--elev-2); transform: translateY(-1px); }

/* ---- Dialog ---- */
.dialog {
  border: none;
  border-radius: var(--radius-lg);
  background: var(--surface-container-high);
  color: var(--on-surface);
  max-width: 640px;
  width: calc(100% - 32px);
  padding: 0;
  box-shadow: var(--elev-3);
}
.dialog::backdrop { background: rgba(40,28,18,.5); }
.dialog__bar {
  display: flex;
  align-items: center;
  padding: 8px 12px;
  border-bottom: 1px solid var(--outline-variant);
  position: sticky;
  top: 0;
  background: var(--surface-container-high);
  z-index: 1;
}
.dialog__spacer { flex: 1; }
.dialog__body { padding: 28px; }
.dialog__body h2 {
  margin-top: 0;
  font-family: var(--font-serif);
  font-weight: 500;
  font-size: 1.5rem;
  line-height: 1.2;
  color: var(--on-surface);
}
.dialog__body > p { color: var(--on-surface-variant); line-height: 1.7; }
.dialog__body .card__tags { margin: 0 0 16px; }
.dialog__body h3 {
  font-family: var(--font-serif);
  font-weight: 500;
  font-size: 1.15rem;
  margin: 22px 0 10px;
  color: var(--on-surface);
}
.dialog__list { margin: 0; padding-left: 20px; }
.dialog__list li { margin-bottom: 9px; line-height: 1.6; color: var(--on-surface-variant); }
.case {
  margin-top: 22px;
  padding: 16px 18px;
  border-radius: var(--radius);
  background: color-mix(in srgb, var(--primary) 8%, var(--surface-container));
  border: 1px solid var(--outline-variant);
}
.case__co {
  margin: 0 0 6px;
  font-size: .76rem;
  font-weight: 700;
  letter-spacing: .06em;
  text-transform: uppercase;
  color: var(--primary);
}
.case p:last-child { margin: 0; line-height: 1.65; color: var(--on-surface-variant); }
.case__link { color: var(--primary); font-weight: 700; }

/* ---- Footer ---- */
.footer {
  text-align: center;
  padding: 36px 20px;
  margin-top: 36px;
  max-width: 720px;
  margin-left: auto;
  margin-right: auto;
  color: var(--on-surface-variant);
  font-size: .84rem;
  line-height: 1.6;
  border-top: 1px solid var(--outline-variant);
}

/* ---- Responsive ---- */
@media (max-width: 600px) {
  .grid, .quotes-grid { grid-template-columns: 1fr; }
  .icon-btn__txt { font-size: .8rem; }
  .section { padding-top: 48px; padding-left: 16px; padding-right: 16px; }
  .dialog__body { padding: 22px; }
}
@media (max-width: 375px) {
  .appbar__inner, .sectionnav__inner, .section { padding-left: 14px; padding-right: 14px; }
  .hero__stats { grid-template-columns: repeat(2, 1fr); }
  .hero__stat-value { font-size: 2rem; }
}

/* Respect reduced-motion: skip smooth scroll + transitions */
@media (prefers-reduced-motion: reduce) {
  html { scroll-behavior: auto; }
  * { transition: none !important; }
}