/* =====================================================================
 * abt-common.css — Upstream landing pages shared design system
 * Loaded by all 33 pages; cached across sessions.
 * Page-specific styles (calculator, decision engine, stack assessor,
 * widget cards) remain inline per page.
 * ===================================================================== */

/* ===== Base scope ===== */
#abt { font-family: 'Inter', system-ui, sans-serif; color: #0a0a0c; background: #faf8f5; scroll-behavior: smooth; }
#abt * { box-sizing: border-box; }
#abt h1, #abt h2 { font-family: 'Fraunces', 'Inter Tight', serif; letter-spacing: -0.025em; }
#abt h3, #abt h4 { font-family: 'Inter', sans-serif; letter-spacing: -0.015em; }
#abt .font-mono { font-family: 'JetBrains Mono', ui-monospace, monospace; }
#abt .font-display { font-family: 'Fraunces', serif; }
#abt .accent-text { color: #2563eb; }
#abt .accent-bg { background: #2563eb; }
#abt .ink { color: #0a0a0c; }
#abt .muted { color: #57534e; }
#abt .paper { background: #faf8f5; }
#abt .paper-cream { background: #f5f1ea; }

/* Twemoji emoji rendering ===== */
#abt img.emoji { height: 1em; width: auto; display: inline-block; vertical-align: -0.12em; margin: 0 1px; }

/* ===== Buttons ===== */
#abt .btn { display: inline-flex; align-items: center; justify-content: center; gap: 0.5rem; padding: 0.95rem 1.4rem; border-radius: 9999px; font-weight: 600; font-size: 0.95rem; transition: all 0.18s ease; text-decoration: none; }
#abt .btn-dark { background: #0a0a0c; color: white; }
#abt .btn-dark:hover { background: #1c1917; transform: translateY(-1px); }
#abt .btn-line { background: transparent; color: #0a0a0c; border: 1px solid #0a0a0c; }
#abt .btn-line:hover { background: #0a0a0c; color: white; }
#abt .btn-accent { background: #2563eb; color: white; }
#abt .btn-accent:hover { background: #1d4ed8; }

/* ===== Eyebrow / bullet ===== */
#abt .eyebrow { display: inline-flex; align-items: center; gap: 0.5rem; font-size: 0.75rem; font-weight: 600; letter-spacing: 0.08em; text-transform: uppercase; color: #57534e; }
#abt .eyebrow .bullet { width: 6px; height: 6px; border-radius: 999px; background: #2563eb; }

/* ===== Brand / logo ===== */
#abt .abt-brand-logo { height: 56px; width: auto; max-width: 280px; display: block; }
@media (max-width: 640px) { #abt .abt-brand-logo { height: 44px; max-width: 200px; } }
@media (max-width: 380px) { #abt .abt-brand-logo { height: 38px; max-width: 160px; } #abt .abt-header .btn { padding: 0.5rem 0.75rem; font-size: 0.78rem; } }
#abt .abt-brand-mark { width: 30px; height: 30px; background: linear-gradient(135deg, #1d4ed8 0%, #3b82f6 100%); color: white; border-radius: 7px; display: inline-flex; align-items: center; justify-content: center; font-weight: 800; font-size: 0.9rem; }
#abt .abt-brand-name { font-weight: 700; letter-spacing: -0.01em; font-size: 1.05rem; }

/* ===== Header ===== */
#abt .abt-header { position: sticky; top: 0; z-index: 40; background: rgba(250,248,245,0.88); backdrop-filter: blur(12px); -webkit-backdrop-filter: blur(12px); border-bottom: 1px solid rgba(10,10,12,0.06); }
#abt .abt-header-inner { display: flex; align-items: center; justify-content: space-between; padding: 0.9rem 0; }
#abt .abt-brand { display: inline-flex; align-items: center; gap: 0.6rem; text-decoration: none; color: inherit; }
#abt .abt-header .btn { padding: 0.6rem 1.1rem; font-size: 0.85rem; }

/* ===== Footer ===== */
#abt .abt-footer { background: #0a0a0c; color: #d6d3d1; }
#abt .abt-footer h4 { color: #fafaf9; }
#abt .abt-footer a { transition: color 0.15s ease; }
#abt .abt-footer a:hover { color: white; }
#abt .abt-footer .abt-brand-mark { background: white; color: #0a0a0c; }
#abt .abt-footer .abt-brand-name { color: white; }

/* ===== Pricing-tier comparison table (common across most tool pages) ===== */
#abt .ptier { background: white; border: 1px solid rgba(10,10,12,0.1); border-radius: 18px; overflow: hidden; }
#abt .ptier-header { display: grid; grid-template-columns: 1.3fr 1fr 1fr 1fr; gap: 0.8rem; padding: 1rem 1.4rem; background: rgba(10,10,12,0.04); border-bottom: 1px solid rgba(10,10,12,0.08); font-family: 'JetBrains Mono', monospace; font-size: 0.7rem; font-weight: 700; text-transform: uppercase; letter-spacing: 0.06em; color: #57534e; }
@media (max-width: 768px) { #abt .ptier-header { grid-template-columns: 1.3fr 1fr 1fr; } #abt .ptier-header > :nth-child(4) { display: none; } }
#abt .ptier-row { display: grid; grid-template-columns: 1.3fr 1fr 1fr 1fr; gap: 0.8rem; padding: 1rem 1.4rem; border-bottom: 1px solid rgba(10,10,12,0.05); align-items: baseline; }
@media (max-width: 768px) { #abt .ptier-row { grid-template-columns: 1.3fr 1fr 1fr; } #abt .ptier-row > :nth-child(4) { display: none; } }
#abt .ptier-row:last-child { border-bottom: 0; }
#abt .ptier-list { font-weight: 600; color: #0a0a0c; font-size: 0.92rem; }
#abt .ptier-list .sub { display: block; font-family: 'JetBrains Mono', monospace; font-size: 0.7rem; color: #78716c; font-weight: 400; margin-top: 0.15rem; }
#abt .ptier-cost { font-family: 'JetBrains Mono', monospace; font-size: 0.92rem; font-weight: 700; }
#abt .ptier-cost.bad { color: #b91c1c; }
#abt .ptier-cost.good { color: #047857; }
#abt .ptier-saving { font-family: 'JetBrains Mono', monospace; font-size: 1rem; font-weight: 800; color: #047857; }

/* ===== Architecture diagram (common across tool pages) ===== */
#abt .arch-flow { display: grid; grid-template-columns: 1fr; gap: 1rem; align-items: stretch; }
@media (min-width: 768px) { #abt .arch-flow { grid-template-columns: 1fr auto 1fr auto 1fr; gap: 0.5rem; align-items: center; } }
#abt .arch-block { background: white; border: 1px solid rgba(10,10,12,0.1); border-radius: 14px; padding: 1.2rem 1.3rem; }
#abt .arch-block-tag { font-family: 'JetBrains Mono', monospace; font-size: 0.62rem; letter-spacing: 0.1em; text-transform: uppercase; color: #2563eb; font-weight: 700; margin-bottom: 0.4rem; }
#abt .arch-block-h { font-family: 'Fraunces', serif; font-size: 1.05rem; font-weight: 700; color: #0a0a0c; line-height: 1.2; margin-bottom: 0.5rem; letter-spacing: -0.01em; }
#abt .arch-block-list { font-size: 0.78rem; color: #57534e; line-height: 1.55; }
#abt .arch-block-list li { padding: 0.1rem 0; padding-left: 0.9rem; position: relative; list-style: none; }
#abt .arch-block-list li::before { content: '·'; position: absolute; left: 0.2rem; color: #2563eb; font-weight: 800; font-size: 1.2rem; line-height: 1; }
#abt .arch-arrow { display: flex; align-items: center; justify-content: center; font-family: 'JetBrains Mono', monospace; font-size: 1.4rem; color: #2563eb; font-weight: 800; }
@media (max-width: 767px) { #abt .arch-arrow { transform: rotate(90deg); padding: 0.3rem 0; } }

/* ===== Parity matrix (common across tool pages) ===== */
#abt .parity-row { display: grid; grid-template-columns: 1fr 1.2rem; gap: 0.8rem; padding: 0.7rem 0; border-bottom: 1px solid rgba(10,10,12,0.06); align-items: baseline; }
#abt .parity-row:last-child { border-bottom: 0; }
#abt .parity-feature { font-size: 0.92rem; color: #0a0a0c; }
#abt .parity-feature .sub { display: block; font-size: 0.78rem; color: #57534e; margin-top: 0.15rem; line-height: 1.45; }
#abt .parity-mark { font-family: 'JetBrains Mono', monospace; font-weight: 700; font-size: 1rem; }
#abt .parity-mark.yes { color: #047857; }
#abt .parity-mark.partial { color: #b45309; }
#abt .parity-mark.dropped { color: #b91c1c; }

/* ===== Pricing card (common across tool pages) ===== */
#abt .price-card { background: white; border: 2px solid #2563eb; border-radius: 18px; padding: 2rem; box-shadow: 0 0 0 6px rgba(37,99,235,0.05), 0 16px 40px -12px rgba(37,99,235,0.18); }
#abt .price-card-tag { font-family: 'JetBrains Mono', monospace; font-size: 0.65rem; letter-spacing: 0.12em; text-transform: uppercase; color: #2563eb; font-weight: 700; margin-bottom: 0.5rem; }
#abt .price-card-h { font-family: 'Fraunces', serif; font-size: 1.7rem; font-weight: 700; color: #0a0a0c; line-height: 1.15; letter-spacing: -0.02em; margin-bottom: 0.4rem; }
#abt .price-card-amt { font-family: 'JetBrains Mono', monospace; font-size: 2.4rem; font-weight: 800; color: #0a0a0c; line-height: 1; margin: 0.6rem 0 0.3rem; }
#abt .price-card-amt .small { font-size: 1rem; color: #57534e; font-weight: 600; }
#abt .price-card-amt-sub { font-family: 'JetBrains Mono', monospace; font-size: 0.78rem; color: #78716c; margin-bottom: 1.2rem; }
#abt .price-card-includes { font-size: 0.9rem; color: #57534e; line-height: 1.7; padding: 1rem 0; border-top: 1px dashed rgba(10,10,12,0.1); border-bottom: 1px dashed rgba(10,10,12,0.1); margin-bottom: 1.2rem; }
#abt .price-card-includes ul { list-style: none; padding: 0; margin: 0; }
#abt .price-card-includes li { padding: 0.18rem 0; padding-left: 1.4rem; position: relative; }
#abt .price-card-includes li::before { content: '✓'; position: absolute; left: 0; color: #047857; font-family: 'JetBrains Mono', monospace; font-weight: 800; }

/* ===== Alt-path cards (common across tool pages) ===== */
#abt .alt-path { background: rgba(185,28,28,0.04); border: 1px solid rgba(185,28,28,0.18); border-radius: 14px; padding: 1.2rem 1.4rem; }
#abt .alt-path-h { font-family: 'Fraunces', serif; font-size: 1.05rem; font-weight: 700; color: #0a0a0c; margin-bottom: 0.4rem; line-height: 1.2; }
#abt .alt-path-tag { font-family: 'JetBrains Mono', monospace; font-size: 0.62rem; letter-spacing: 0.1em; text-transform: uppercase; color: #b91c1c; font-weight: 700; margin-bottom: 0.4rem; }
#abt .alt-path-body { font-size: 0.85rem; color: #57534e; line-height: 1.55; }
#abt .alt-path-body strong { color: #0a0a0c; }

/* ===== Reveal-on-scroll animation ===== */
#abt .reveal { opacity: 0; transform: translateY(22px); transition: opacity 0.7s cubic-bezier(0.16, 1, 0.3, 1), transform 0.7s cubic-bezier(0.16, 1, 0.3, 1); }
#abt .reveal.in { opacity: 1; transform: translateY(0); }

/* ===== Reading progress bar ===== */
#abt-progress { position: fixed; top: 0; left: 0; height: 3px; width: 0%; background: linear-gradient(90deg, #1d4ed8, #3b82f6); z-index: 100; pointer-events: none; transition: width 0.06s linear; box-shadow: 0 0 8px rgba(37,99,235,0.4); }

/* ===== Tabular numerals for animated counters ===== */
#abt [data-counter] { font-variant-numeric: tabular-nums; }

/* ===== Sticky CTA (floating bottom-right) ===== */
#abt-sticky-cta { position: fixed; bottom: 1.5rem; right: 1.5rem; z-index: 50; opacity: 0; transform: translateY(20px) scale(0.96); pointer-events: none; transition: opacity 0.3s ease, transform 0.3s ease; }
#abt-sticky-cta.visible { opacity: 1; transform: translateY(0) scale(1); pointer-events: auto; }
#abt-sticky-cta a { box-shadow: 0 14px 36px -8px rgba(37,99,235,0.45), 0 4px 12px rgba(0,0,0,0.08); padding: 0.85rem 1.3rem; font-size: 0.88rem; }

/* ===== Hero gradient mesh (used on every page hero) ===== */
#abt .hero-mesh { position: absolute; inset: 0; pointer-events: none; z-index: 0; opacity: 0.85; overflow: hidden; }
#abt .hero-mesh::before, #abt .hero-mesh::after { content: ''; position: absolute; border-radius: 50%; filter: blur(90px); }
#abt .hero-mesh::before { width: 640px; height: 640px; top: -160px; right: -180px; background: radial-gradient(circle, rgba(37,99,235,0.16) 0%, transparent 60%); animation: drift1 22s ease-in-out infinite; }
#abt .hero-mesh::after  { width: 520px; height: 520px; bottom: -140px; left: -120px; background: radial-gradient(circle, rgba(59,130,246,0.12) 0%, transparent 60%); animation: drift2 26s ease-in-out infinite; }
@keyframes drift1 { 0%, 100% { transform: translate(0, 0); } 50% { transform: translate(-50px, 70px); } }
@keyframes drift2 { 0%, 100% { transform: translate(0, 0); } 50% { transform: translate(80px, -50px); } }

/* ===== Details / FAQ ===== */
#abt details > summary { list-style: none; cursor: pointer; }
#abt details > summary::-webkit-details-marker { display: none; }
#abt details[open] summary .chev { transform: rotate(180deg); }
#abt .chev { transition: transform 0.2s ease; display: inline-block; }

/* ===== Cross-link strip / chips ===== */
#abt .xlink-strip { display: flex; gap: 0.5rem; flex-wrap: wrap; align-items: center; }
#abt .xlink-chip { padding: 0.45rem 0.9rem; border-radius: 9999px; font-size: 0.8rem; font-weight: 500; color: #0a0a0c; background: white; border: 1px solid rgba(10,10,12,0.1); transition: all 0.15s; text-decoration: none; }
#abt .xlink-chip:hover { border-color: #2563eb; color: #2563eb; transform: translateY(-1px); }

/* ===== Loss-line annotation ===== */
.loss-line { font-size: 0.78rem; color: #fda4af; margin-top: 0.6rem; line-height: 1.4; }
.loss-line strong { color: #fca5a5; }

/* ===== Mobile responsive overrides (end-of-cascade source-order win) ===== */
@media (max-width: 640px) {
  #abt .abt-header-inner { padding: 0.65rem 0; }
  #abt .abt-header .btn { padding: 0.5rem 0.85rem; font-size: 0.8rem; }
  #abt .abt-brand { gap: 0.5rem; }
}
@media (max-width: 380px) {
  #abt .abt-header .btn { padding: 0.45rem 0.7rem; font-size: 0.75rem; letter-spacing: -0.01em; }
}