/* css/use-case.css — shell for the use-case pages (/newsletter-for-creators,
   /tw/newsletter). The base rules are the landing's own inline <style> (index.html),
   copied rather than re-invented, so css/landing-editorial.css — loaded AFTER this
   file — dresses these pages exactly as it dresses the landing. Everything new is
   prefixed .uc- so the editorial layer never touches it. */
:root {
  --blue-10:#EDF3FF; --blue-20:#DFEAFF; --blue-30:#CBDEFF; --blue-50:#5090FF; --blue-60:#3A7AEF; --blue-70:#2A63D4; --blue-90:#1E3A5F;
  --purple:#801FF9; --text:#334155; --text-2:#4B5563; --text-3:#6B7280; --border:#E2E8F0; --surface-2:#F7F9FC;
  --green:#47D7AC; --green-deep:#0F8F6B;
  --font:"Inter","Outfit","Noto Sans TC","PingFang TC",sans-serif;
  --font-display:"Outfit","Inter","Noto Sans TC",sans-serif;
  --font-mono:"SF Mono","JetBrains Mono",ui-monospace,Menlo,monospace;
}
* { box-sizing: border-box; }
html { scroll-behavior: smooth; }
html, body { margin: 0; font-family: var(--font); color: var(--text); background: #fff; -webkit-font-smoothing: antialiased; }
body { font-size: 16px; line-height: 1.55; }
a { color: inherit; text-decoration: none; }
img { max-width: 100%; display: block; }
nav.top { position: sticky; top: 0; background: rgba(255,255,255,0.9); backdrop-filter: blur(12px); border-bottom: 1px solid var(--border); z-index: 50; padding: 12px 32px; display: flex; align-items: center; gap: 22px; }
.brand { display: flex; align-items: center; gap: 10px; font-family: var(--font-display); font-weight: 800; font-size: 20px; color: var(--blue-50); flex-shrink: 0; }
.brand small { font-size: 11px; font-weight: 700; color: var(--text-3); letter-spacing: 0.1em; }
.nav-links { display: flex; gap: 20px; font-size: 14px; font-weight: 500; color: var(--text-2); }
.nav-links a:hover { color: var(--blue-60); }
.nav-cta { margin-left: auto; display: flex; gap: 10px; align-items: center; }
.btn { display: inline-flex; align-items: center; gap: 8px; padding: 10px 22px; border-radius: 999px; font-weight: 700; font-size: 14px; transition: all 0.18s; white-space: nowrap; }
.btn-primary { background: var(--blue-50); color: #fff; }
.btn-ghost { color: var(--blue-60); }
.btn-lg { padding: 14px 32px; font-size: 16px; }
.btn-xl { padding: 17px 40px; font-size: 17px; }
.hero { padding: 74px 32px 64px; overflow: hidden; }
.hero-grid { max-width: 1160px; margin: 0 auto; display: grid; grid-template-columns: 1fr; gap: 52px; align-items: center; }
.eyebrow { display: inline-flex; align-items: center; gap: 8px; padding: 6px 14px; background: var(--blue-10); color: var(--blue-70); font-size: 12.5px; font-weight: 700; letter-spacing: 0.08em; border-radius: 999px; margin-bottom: 20px; border: 1px solid var(--blue-20); }
.eyebrow .pulse { width: 6px; height: 6px; border-radius: 50%; background: var(--green); }
h1 { font-family: var(--font-display); font-size: 54px; font-weight: 900; line-height: 1.06; letter-spacing: -0.04em; margin: 0 0 18px; color: var(--blue-90); }
h1 em { font-style: normal; background: linear-gradient(135deg,var(--blue-50),var(--purple)); -webkit-background-clip: text; background-clip: text; color: transparent; }
.lead { font-size: 18.5px; line-height: 1.55; color: var(--text-2); margin: 0 0 30px; max-width: 520px; }
.hero-ctas { display: flex; gap: 12px; flex-wrap: wrap; align-items: center; margin-bottom: 26px; }
.trust-line { display: flex; gap: 18px; color: var(--text-3); font-size: 13px; flex-wrap: wrap; margin-top: 22px; }
.trust-line span { display: flex; align-items: center; gap: 6px; }
.trust-line svg { color: var(--green-deep); flex-shrink: 0; }
section.sect { padding: 96px 32px; }
section.sect.alt { background: var(--surface-2); }
.wrap { max-width: 1080px; margin: 0 auto; }
.sect-head { text-align: center; margin-bottom: 44px; }
.sect-eyebrow { font-size: 13px; font-weight: 700; letter-spacing: 0.14em; color: var(--blue-60); margin-bottom: 14px; }
h2 { font-family: var(--font-display); font-size: 40px; font-weight: 800; letter-spacing: -0.02em; line-height: 1.12; margin: 0 0 12px; color: var(--blue-90); }
.sect-head p { color: var(--text-2); font-size: 17px; max-width: 620px; margin: 0 auto; }
.faq { max-width: 680px; margin: 0 auto; }
details { background: #fff; border: 1px solid var(--border); border-radius: 14px; margin-bottom: 10px; }
summary { cursor: pointer; padding: 16px 20px; font-weight: 700; font-size: 15px; color: var(--blue-90); list-style: none; display: flex; justify-content: space-between; gap: 12px; }
summary::-webkit-details-marker { display: none; }
summary::after { content: "+"; color: var(--blue-50); font-weight: 700; }
details[open] summary::after { content: "\2212"; }
.faq-body { padding: 0 20px 16px; font-size: 14px; color: var(--text-2); line-height: 1.7; }
.faq-body a { color: var(--blue-60); text-decoration: underline; text-underline-offset: 3px; }
.final { text-align: center; padding: 110px 32px; }
.final h2 { font-size: 46px; }
.final p { color: var(--text-2); font-size: 17px; margin: 0 0 32px; }
footer { background: #fff; border-top: 1px solid var(--border); padding: 30px 32px; }
footer .frow { max-width: 1080px; margin: 0 auto; display: flex; justify-content: space-between; gap: 16px; flex-wrap: wrap; font-size: 13px; color: var(--text-3); }
@media (max-width: 900px) {
  h1 { font-size: 38px; } h2 { font-size: 29px; } .final h2 { font-size: 32px; }
  .nav-links, .nav-login { display: none; }
  nav.top { padding: 11px 16px; gap: 10px; }
  .brand small { display: none; }
  .btn { padding: 9px 16px; font-size: 13.5px; }
}

/* ---- use-case components ------------------------------------------------ */
.uc .sect { padding: 104px 32px; }
.uc #how, .uc #fit, .uc #features, .uc #pricing, .uc #limits, .uc #faq, .uc #answer { scroll-margin-top: 104px; }
.uc .hero h1 { max-width: 980px; }
.uc .nav-links a { white-space: nowrap; }
.uc .hero h1:lang(zh-Hant) { word-break: keep-all; overflow-wrap: anywhere; }
.uc-wrap { max-width: var(--cl-content-w, 1200px); margin: 0 auto; }
.uc-narrow { max-width: 900px; margin: 0 auto; }
.uc-updated { margin: 18px 0 0; font-size: 13px; color: var(--cl-fg-3, #6B7280); }

/* The short answer: a paragraph an assistant can quote, then the facts as a list. */
.uc-answer { background: #fff; border: 1px solid var(--cl-border, #E4E4E4); border-radius: var(--cl-radius-l, 32px); box-shadow: var(--cl-shadow-card); padding: 44px 48px; }
.uc-answer > p { margin: 0 0 28px; font-size: var(--cl-para-l, 17.6px); line-height: 1.8; color: var(--cl-fg-1, #222A36); }
.uc-facts { display: grid; grid-template-columns: repeat(2, minmax(0, 1fr)); gap: 0 36px; margin: 0; }
.uc-facts > div { display: grid; grid-template-columns: 112px 1fr; gap: 16px; padding: 14px 0; border-top: 1px solid var(--cl-border-soft, #EEE); }
.uc-facts dt { font-size: 14px; font-weight: 600; color: var(--cl-fg-3, #6B7280); }
.uc-facts dd { margin: 0; font-size: 15px; line-height: 1.6; color: var(--cl-fg-1, #222A36); }

/* Fit / not a fit */
.uc-fit { display: grid; grid-template-columns: repeat(2, minmax(0, 1fr)); gap: 20px; }
.uc-card { background: #fff; border: 1px solid var(--cl-border, #E4E4E4); border-radius: var(--cl-radius-l, 32px); box-shadow: var(--cl-shadow-card); padding: 36px 38px; }
.uc-card h3 { margin: 0 0 18px; font-size: 22px; line-height: 1.35; color: var(--cl-fg-1, #222A36); font-weight: 700; }
.uc-list { list-style: none; margin: 0; padding: 0; display: flex; flex-direction: column; gap: 14px; }
.uc-list li { display: grid; grid-template-columns: 24px 1fr; gap: 10px; font-size: 16px; line-height: 1.65; color: var(--cl-fg-2, #4D5977); }
.uc-list li b { color: var(--cl-fg-1, #222A36); font-weight: 600; }
.uc-mark { width: 22px; height: 22px; margin-top: 3px; border-radius: 50%; display: grid; place-items: center; font-size: 12px; font-weight: 700; line-height: 1; }
.uc-yes .uc-mark { color: #fff; background: var(--cl-blue, #5090FF); }
.uc-no .uc-mark { color: var(--cl-fg-2, #4D5977); background: var(--cl-bg-tint, #F8F9FC); border: 1px solid var(--cl-border, #E4E4E4); }
.uc-list a, .uc-card p a, .uc-note a { color: var(--cl-blue, #5090FF); text-decoration: underline; text-underline-offset: 3px; }

/* Three steps */
.uc-steps { display: grid; grid-template-columns: repeat(3, minmax(0, 1fr)); gap: 20px; counter-reset: uc-step; list-style: none; margin: 0; padding: 0; }
.uc-steps > li { background: #fff; border: 1px solid var(--cl-border, #E4E4E4); border-radius: var(--cl-radius-l, 32px); box-shadow: var(--cl-shadow-card); padding: 36px 34px; }
.uc-steps .uc-n { width: 38px; height: 38px; border-radius: 50%; display: grid; place-items: center; color: #fff; background: var(--cl-gradient-blue-h, #5090FF); font-weight: 700; font-size: 16px; }
.uc-steps h3 { margin: 28px 0 10px; font-size: 22px; line-height: 1.35; color: var(--cl-fg-1, #222A36); font-weight: 700; }
.uc-steps p { margin: 0; font-size: 15.5px; line-height: 1.75; color: var(--cl-fg-2, #4D5977); }
.uc-steps code, .uc-card code, .uc-facts code, .faq-body code { font-family: var(--font-mono); font-size: .88em; background: var(--cl-blue-bg-2, #EEF4FF); border-radius: 6px; padding: 1px 6px; color: var(--cl-fg-1, #222A36); word-break: break-word; }

/* What you get */
.uc-feats { display: grid; grid-template-columns: repeat(3, minmax(0, 1fr)); gap: 20px; }
.uc-feat { background: #fff; border-radius: var(--cl-radius-m, 20px); box-shadow: var(--cl-shadow-card); padding: 30px; }
.uc-feat .cred-mark { margin-bottom: 18px; }
.uc-feat h3 { margin: 0 0 8px; font-size: 18px; line-height: 1.35; color: var(--cl-fg-1, #222A36); font-weight: 700; }
.uc-feat p { margin: 0; font-size: 15px; line-height: 1.7; color: var(--cl-fg-3, #6B7280); }

/* Pricing */
.uc-price { display: grid; grid-template-columns: minmax(0, 1.1fr) minmax(0, .9fr); gap: 20px; align-items: start; }
.uc-table-wrap { background: #fff; border: 1px solid var(--cl-border, #E4E4E4); border-radius: var(--cl-radius-l, 32px); box-shadow: var(--cl-shadow-card); padding: 18px 26px 8px; overflow-x: auto; }
.uc-table { width: 100%; border-collapse: collapse; font-size: 15px; }
.uc-table caption { text-align: left; padding: 12px 0 8px; font-weight: 700; font-size: 17px; color: var(--cl-fg-1, #222A36); }
.uc-table th, .uc-table td { padding: 12px 8px; border-bottom: 1px solid var(--cl-border-soft, #EEE); text-align: left; color: var(--cl-fg-2, #4D5977); }
.uc-table tr:last-child td { border-bottom: 0; }
.uc-table th { font-size: 12.5px; font-weight: 600; letter-spacing: .04em; color: var(--cl-fg-3, #6B7280); }
.uc-table td.n, .uc-table th.n { text-align: right; font-variant-numeric: tabular-nums; }
.uc-table td b { color: var(--cl-fg-1, #222A36); font-weight: 700; }
.uc-side { display: flex; flex-direction: column; gap: 20px; }
.uc-side .uc-card { padding: 30px 32px; }
.uc-side .uc-card h3 { font-size: 19px; margin-bottom: 14px; }
.uc-ex { list-style: none; margin: 0; padding: 0; display: flex; flex-direction: column; gap: 14px; }
.uc-ex li { font-size: 15px; line-height: 1.6; color: var(--cl-fg-2, #4D5977); padding-bottom: 14px; border-bottom: 1px solid var(--cl-border-soft, #EEE); }
.uc-ex li:last-child { border-bottom: 0; padding-bottom: 0; }
.uc-ex b { display: block; color: var(--cl-fg-1, #222A36); font-size: 17px; font-weight: 700; margin-bottom: 2px; }
.uc-note { margin: 0; font-size: 14px; line-height: 1.7; color: var(--cl-fg-3, #6B7280); }
.uc-note + .uc-note { margin-top: 10px; }

/* Honest limits */
.uc-limits { display: grid; grid-template-columns: repeat(2, minmax(0, 1fr)); gap: 16px; }
.uc-limit { background: #fff; border: 1px solid var(--cl-border, #E4E4E4); border-radius: var(--cl-radius-m, 20px); padding: 26px 28px; }
.uc-limit h3 { margin: 0 0 6px; font-size: 17px; line-height: 1.4; color: var(--cl-fg-1, #222A36); font-weight: 700; }
.uc-limit p { margin: 0; font-size: 15px; line-height: 1.7; color: var(--cl-fg-2, #4D5977); }

footer .frow a { color: var(--cl-fg-2, #4D5977); }
footer .frow a:hover { color: var(--cl-blue, #5090FF); }

@media (max-width: 900px) {
  .uc .sect { padding: 84px 24px; }
  .uc-fit, .uc-steps, .uc-feats, .uc-price, .uc-limits { grid-template-columns: 1fr; }
  .uc-facts { grid-template-columns: 1fr; }
  .uc-answer { padding: 32px 28px; }
}
@media (max-width: 560px) {
  .uc .sect { padding: 72px 16px; }
  .uc-answer, .uc-card, .uc-steps > li { padding: 26px 22px; border-radius: 24px; }
  .uc-facts > div { grid-template-columns: 1fr; gap: 4px; }
  .uc-table-wrap { padding: 10px 14px 4px; border-radius: 24px; }
  .uc-table { font-size: 14px; }
  .uc-table th, .uc-table td { padding: 10px 6px; }
  footer { padding: 26px 16px; }
}
@media (max-width: 380px) {
  .uc .hero h1 { font-size: 34px; }
}