:root {
  --ink: #17313c;
  --blue: #123f56;
  --accent: #d56b3f;
  --paper: #f3efe6;
  --line: rgba(23, 49, 60, .18);
  --muted: #718087;
}

* { box-sizing: border-box; }
html { scroll-behavior: smooth; }
body {
  margin: 0;
  color: var(--ink);
  background:
    linear-gradient(rgba(18, 63, 86, .035) 1px, transparent 1px),
    linear-gradient(90deg, rgba(18, 63, 86, .035) 1px, transparent 1px),
    var(--paper);
  background-size: 32px 32px;
  font-family: "Noto Sans TC", "Microsoft JhengHei", sans-serif;
}

.topbar {
  height: 84px;
  padding: 0 clamp(24px, 5vw, 72px);
  display: flex;
  align-items: center;
  justify-content: space-between;
  border-bottom: 1px solid var(--line);
  background: rgba(243, 239, 230, .9);
  backdrop-filter: blur(14px);
  position: sticky;
  top: 0;
  z-index: 10;
}
.brand { display: flex; align-items: center; gap: 13px; }
.brand-mark {
  width: 42px; height: 42px; display: grid; place-items: center;
  color: var(--paper); background: var(--blue); font: 700 14px/1 Georgia, serif;
}
.brand div { display: grid; gap: 2px; }
.brand strong { font-size: 15px; letter-spacing: .12em; }
.brand div span { color: var(--muted); font-size: 12px; }
.read-only { color: var(--muted); font-size: 12px; display: flex; align-items: center; gap: 8px; }
.read-only span { width: 7px; height: 7px; background: #4d8c6b; border-radius: 50%; box-shadow: 0 0 0 4px rgba(77,140,107,.12); }

main { width: min(1080px, calc(100% - 48px)); margin: 0 auto; }
.intro { padding: 88px 0 72px; display: grid; grid-template-columns: 1fr 1fr; align-items: end; gap: 40px; }
.eyebrow { margin: 0 0 18px; color: var(--accent); font: 700 11px/1.2 Arial, sans-serif; letter-spacing: .18em; }
.intro .eyebrow { grid-column: 1 / -1; margin-bottom: -16px; }
h1 { margin: 0; color: var(--blue); font: 600 clamp(42px, 6.5vw, 78px)/1.08 Georgia, "Noto Serif TC", serif; letter-spacing: -.045em; }
.intro-copy { max-width: 420px; margin: 0 0 8px; color: var(--muted); font-size: 15px; line-height: 1.9; }

.lark-connect {
  margin-bottom: 28px;
  padding: 34px 40px;
  color: white;
  background: var(--blue);
  display: grid;
  grid-template-columns: 1.25fr 1fr auto;
  gap: 32px;
  align-items: end;
}
.lark-copy .eyebrow { margin-bottom: 12px; }
.lark-copy h2 { margin: 0 0 8px; font: 600 24px/1.2 Georgia, "Noto Serif TC", serif; }
.lark-copy > p:last-child { margin: 0; color: rgba(255,255,255,.65); font-size: 12px; }
.lark-fields { display: grid; grid-template-columns: 1fr 1fr; gap: 16px; }
.lark-fields label { color: rgba(255,255,255,.65); }
.lark-fields input { color: white; border-color: rgba(255,255,255,.28); }
.lark-fields input::placeholder { color: rgba(255,255,255,.35); }
.lark-fields input:focus { background: rgba(255,255,255,.07); border-color: var(--accent); }
#lark-generate-button { min-width: 220px; color: var(--blue); background: white; display: flex; justify-content: space-between; align-items: center; }
#lark-generate-button:hover { background: #f4e8dd; }
#lark-generate-button i { font-style: normal; font-size: 20px; }

.workspace { border-top: 2px solid var(--blue); background: rgba(250,248,242,.78); padding: 0 clamp(24px, 5vw, 64px) 56px; box-shadow: 0 18px 60px rgba(22,49,60,.08); }
.section-heading { display: grid; grid-template-columns: 58px 1fr; gap: 18px; padding: 42px 0 28px; }
.section-heading.divider { border-top: 1px solid var(--line); margin-top: 42px; }
.section-heading > span { color: var(--accent); font: 700 12px/1 Arial, sans-serif; padding-top: 7px; }
.section-heading h2 { margin: 0 0 5px; font: 600 24px/1.2 Georgia, "Noto Serif TC", serif; }
.section-heading p { margin: 0; color: var(--muted); font-size: 12px; }
.field-grid { display: grid; grid-template-columns: 1fr 1fr; gap: 24px 28px; padding-left: 76px; }
label { display: grid; gap: 9px; color: var(--muted); font-size: 12px; letter-spacing: .05em; }
label.wide { grid-column: 1 / -1; }
input, textarea {
  width: 100%; border: 0; border-bottom: 1px solid var(--line); border-radius: 0;
  padding: 12px 2px; color: var(--ink); background: transparent; font: 500 15px/1.6 inherit;
  transition: border-color .2s, background .2s;
}
textarea { resize: vertical; padding: 12px; border: 1px solid var(--line); }
input:focus, textarea:focus { outline: 0; border-color: var(--accent); background: rgba(255,255,255,.5); }

.action-row { margin: 56px 0 0 76px; padding-top: 28px; border-top: 1px solid var(--line); display: flex; justify-content: flex-end; gap: 12px; }
button { border: 0; cursor: pointer; font: 700 14px/1 inherit; min-height: 52px; padding: 0 24px; transition: transform .2s, background .2s, opacity .2s; }
button:hover { transform: translateY(-2px); }
button:disabled { cursor: wait; opacity: .62; transform: none; }
#generate-button { min-width: 230px; display: flex; align-items: center; justify-content: space-between; color: white; background: var(--blue); }
#generate-button:hover { background: #0c3347; }
#generate-button i { font-style: normal; font-size: 20px; transition: transform .2s; }
#generate-button:hover i { transform: translateX(5px); }
button.secondary { color: var(--blue); background: transparent; border: 1px solid var(--line); }

.result { margin: 28px 0 80px; padding: 34px 40px; color: white; background: var(--blue); display: grid; grid-template-columns: 1fr 1fr; gap: 32px; animation: result-in .4s ease both; }
.result h2 { margin: 0; font: 600 28px/1.2 Georgia, serif; }
.result p { margin: 0; }
#result-detail { color: rgba(255,255,255,.72); font-size: 13px; line-height: 1.7; }
#result-detail ul { margin: 8px 0 0; padding-left: 18px; }

footer { padding: 24px clamp(24px, 5vw, 72px); border-top: 1px solid var(--line); color: var(--muted); display: flex; justify-content: space-between; font-size: 11px; }
.reveal { animation: reveal .65s cubic-bezier(.2,.7,.2,1) both; }
.workspace.reveal { animation-delay: .12s; }
@keyframes reveal { from { opacity: 0; transform: translateY(18px); } to { opacity: 1; transform: none; } }
@keyframes result-in { from { opacity: 0; transform: translateY(12px) scale(.99); } to { opacity: 1; transform: none; } }

@media (max-width: 720px) {
  .topbar { height: 70px; }
  .read-only { font-size: 0; }
  main { width: min(100% - 28px, 1080px); }
  .intro { padding: 56px 4px 44px; grid-template-columns: 1fr; gap: 24px; }
  .intro .eyebrow { margin-bottom: -4px; }
  h1 { font-size: 45px; }
  .workspace { padding-inline: 20px; }
  .lark-connect { grid-template-columns: 1fr; padding: 28px 22px; gap: 22px; }
  .lark-fields { grid-template-columns: 1fr; }
  #lark-generate-button { width: 100%; }
  .field-grid { grid-template-columns: 1fr; padding-left: 0; }
  label.wide { grid-column: auto; }
  .section-heading { grid-template-columns: 38px 1fr; }
  .action-row { margin-left: 0; flex-direction: column-reverse; }
  #generate-button { width: 100%; }
  .result { grid-template-columns: 1fr; padding: 28px 24px; }
}

@media (prefers-reduced-motion: reduce) {
  *, *::before, *::after { animation: none !important; transition: none !important; scroll-behavior: auto !important; }
}