/* 企業 AI 實作課程 — B2B landing (blue / light blue) */
:root {
  --bg: #f0f6ff;
  --surface: #ffffff;
  --border: #cfe0f8;
  --text: #0c1a33;
  --muted: #5b6f8c;
  --primary: #2563eb;
  --primary-hover: #3b82f6;
  --primary-deep: #1d4ed8;
  --primary-soft: #dbeafe;
  --accent: #0ea5e9;
  --radius: 14px;
  --shadow: 0 1px 3px rgba(12, 26, 51, 0.07), 0 1px 2px rgba(12, 26, 51, 0.04);
  --shadow-md: 0 8px 24px rgba(37, 99, 235, 0.14);
  --font: "Noto Sans TC", "PingFang TC", "Microsoft JhengHei", system-ui, sans-serif;
  --max: 1080px;
}

*, *::before, *::after { box-sizing: border-box; }
html { scroll-behavior: smooth; }
body {
  margin: 0;
  font-family: var(--font);
  background: var(--bg);
  color: var(--text);
  line-height: 1.6;
  min-height: 100vh;
}
img { max-width: 100%; }
a { color: var(--primary); }
a:hover { color: var(--primary-hover); }

.skip-link {
  position: absolute;
  left: -9999px;
  top: 0;
  background: var(--primary);
  color: #fff;
  padding: 0.5rem 1rem;
  z-index: 100;
}
.skip-link:focus { left: 0.5rem; top: 0.5rem; }

.inner {
  max-width: var(--max);
  margin: 0 auto;
  padding: 0 1.25rem;
}
.inner.narrow { max-width: 720px; }

/* Header */
.site-header {
  position: sticky;
  top: 0;
  z-index: 40;
  background: rgba(255, 255, 255, 0.92);
  backdrop-filter: blur(10px);
  border-bottom: 1px solid var(--border);
  box-shadow: var(--shadow);
}
.site-header .inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 1rem;
  padding-top: 0.75rem;
  padding-bottom: 0.75rem;
}
.brand {
  display: flex;
  align-items: center;
  gap: 0.7rem;
  text-decoration: none;
  color: inherit;
}
.brand-mark {
  width: 40px;
  height: 40px;
  border-radius: 10px;
  background: linear-gradient(135deg, var(--primary), var(--accent));
  color: #fff;
  font-weight: 700;
  font-size: 0.85rem;
  display: grid;
  place-items: center;
}
.brand-text {
  display: flex;
  flex-direction: column;
  line-height: 1.25;
}
.brand-text strong { font-size: 0.95rem; }
.brand-text span { font-size: 0.75rem; color: var(--muted); }

.nav {
  display: none;
  align-items: center;
  gap: 1.1rem;
}
.nav a {
  text-decoration: none;
  color: var(--text);
  font-size: 0.9rem;
  font-weight: 500;
}
.nav a:hover { color: var(--primary); }
.nav-cta {
  background: var(--primary);
  color: #fff !important;
  padding: 0.4rem 0.9rem;
  border-radius: 999px;
  font-weight: 600 !important;
}
.nav-cta:hover { background: var(--primary-hover); }

.nav-toggle {
  display: flex;
  flex-direction: column;
  gap: 5px;
  background: none;
  border: none;
  padding: 0.4rem;
  cursor: pointer;
}
.nav-toggle span {
  display: block;
  width: 22px;
  height: 2px;
  background: var(--text);
  border-radius: 2px;
}
.mobile-nav {
  display: flex;
  flex-direction: column;
  gap: 0.25rem;
  padding: 0.5rem 1.25rem 1rem;
  border-top: 1px solid var(--border);
  background: var(--surface);
}
.mobile-nav[hidden] { display: none !important; }
.mobile-nav a {
  text-decoration: none;
  color: var(--text);
  padding: 0.65rem 0.25rem;
  font-weight: 500;
  border-bottom: 1px solid var(--border);
}

@media (min-width: 860px) {
  .nav { display: flex; }
  .nav-toggle { display: none; }
  .mobile-nav { display: none !important; }
}

/* Hero */
.hero {
  position: relative;
  padding: 3rem 0 3.5rem;
  overflow: hidden;
}
.hero-bg {
  position: absolute;
  inset: 0;
  background:
    radial-gradient(ellipse 80% 60% at 85% 10%, rgba(14, 116, 144, 0.18), transparent 55%),
    radial-gradient(ellipse 70% 50% at 10% 90%, rgba(15, 118, 110, 0.16), transparent 50%),
    linear-gradient(180deg, #dbeafe 0%, var(--bg) 100%);
  z-index: 0;
}
.hero-grid {
  position: relative;
  z-index: 1;
  display: grid;
  gap: 2rem;
}
@media (min-width: 900px) {
  .hero-grid {
    grid-template-columns: 1.15fr 0.85fr;
    align-items: start;
    gap: 2.5rem;
  }
}
.eyebrow {
  display: inline-block;
  margin: 0 0 0.75rem;
  padding: 0.25rem 0.7rem;
  background: var(--primary-soft);
  color: var(--primary-deep);
  border-radius: 999px;
  font-size: 0.8rem;
  font-weight: 600;
}
.hero h1 {
  margin: 0 0 1rem;
  font-size: clamp(1.75rem, 4.5vw, 2.55rem);
  line-height: 1.25;
  letter-spacing: -0.02em;
}
.lead {
  margin: 0 0 1.5rem;
  font-size: 1.05rem;
  color: var(--muted);
  max-width: 36em;
}
.hero-actions {
  display: flex;
  flex-wrap: wrap;
  gap: 0.75rem;
  margin-bottom: 1.25rem;
}
.hero-meta {
  margin: 0;
  font-size: 0.9rem;
  color: var(--text);
  font-weight: 500;
}
.hero-note {
  margin: 0.4rem 0 0;
  font-size: 0.8rem;
  color: var(--muted);
}
.hero-note code, .cta-note code, .format-block code, .faq-item code {
  background: var(--primary-soft);
  padding: 0.1rem 0.35rem;
  border-radius: 4px;
  font-size: 0.85em;
}

.hero-card {
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 1.35rem 1.4rem;
  box-shadow: var(--shadow-md);
}
.hero-card-title {
  margin: 0 0 1rem;
  font-size: 1.05rem;
  color: var(--primary-deep);
}
.hero-card-list {
  list-style: none;
  margin: 0;
  padding: 0;
}
.hero-card-list li {
  display: grid;
  grid-template-columns: 4.5rem 1fr;
  gap: 0.65rem;
  padding: 0.65rem 0;
  border-bottom: 1px solid var(--border);
  font-size: 0.9rem;
}
.hero-card-list li:last-child { border-bottom: none; }
.hero-card-list span { color: var(--muted); font-size: 0.8rem; }
.hero-card-list strong { font-weight: 600; line-height: 1.4; }

/* Buttons */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  padding: 0.7rem 1.35rem;
  border-radius: 999px;
  font-weight: 600;
  font-size: 0.95rem;
  text-decoration: none;
  border: 2px solid transparent;
  cursor: pointer;
  transition: background 0.15s, color 0.15s, border-color 0.15s;
}
.btn-primary {
  background: var(--primary);
  color: #fff !important;
}
.btn-primary:hover { background: var(--primary-hover); }
.btn-secondary {
  background: var(--surface);
  color: var(--primary-deep) !important;
  border-color: var(--border);
}
.btn-secondary:hover {
  border-color: var(--primary);
  background: var(--primary-soft);
}
.btn-ghost {
  background: transparent;
  color: #fff !important;
  border-color: rgba(255, 255, 255, 0.45);
}
.btn-ghost:hover { background: rgba(255, 255, 255, 0.12); }
.btn-lg { padding: 0.85rem 1.6rem; font-size: 1rem; }

/* Sections */
.section { padding: 3.5rem 0; }
.section-alt { background: var(--surface); border-top: 1px solid var(--border); border-bottom: 1px solid var(--border); }
.section-label {
  margin: 0 0 0.4rem;
  font-size: 0.8rem;
  font-weight: 600;
  letter-spacing: 0.04em;
  text-transform: uppercase;
  color: var(--primary);
}
.section h2 {
  margin: 0 0 0.75rem;
  font-size: clamp(1.4rem, 3vw, 1.85rem);
}
.section-intro {
  margin: 0 0 1.75rem;
  color: var(--muted);
  max-width: 40em;
}

.cards {
  display: grid;
  gap: 1.15rem;
}
.cards-2 { grid-template-columns: 1fr; }
.cards-3 { grid-template-columns: 1fr; }
@media (min-width: 640px) {
  .cards-2 { grid-template-columns: repeat(2, 1fr); }
  .cards-3 { grid-template-columns: repeat(2, 1fr); }
}
@media (min-width: 900px) {
  .cards-3 { grid-template-columns: repeat(3, 1fr); }
}
.card {
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 1.35rem;
  box-shadow: var(--shadow);
}
.section-alt .card { background: var(--bg); }
.card-icon { font-size: 1.5rem; margin-bottom: 0.5rem; }
.card h3 { margin: 0 0 0.5rem; font-size: 1.05rem; }
.card p { margin: 0; color: var(--muted); font-size: 0.92rem; }

/* Outcomes checklist */
.checklist {
  list-style: none;
  margin: 0 0 1.75rem;
  padding: 0;
  display: grid;
  gap: 0.85rem;
}
.checklist li {
  display: flex;
  gap: 0.85rem;
  align-items: flex-start;
  background: var(--bg);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 1rem 1.15rem;
}
.checklist .check { font-size: 1.15rem; line-height: 1.4; flex-shrink: 0; }
.checklist h3 { margin: 0 0 0.25rem; font-size: 1rem; }
.checklist p { margin: 0; color: var(--muted); font-size: 0.9rem; }

.offer-banner {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  justify-content: space-between;
  gap: 0.75rem;
  margin: 0;
  padding: 1.1rem 1.35rem;
  background: linear-gradient(135deg, var(--primary-soft), #e0f2fe);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  color: var(--primary-deep);
}
.offer-banner span {
  font-size: 0.9rem;
  font-weight: 600;
  color: var(--muted);
}

/* Format */
.format-grid {
  display: grid;
  gap: 1.15rem;
}
@media (min-width: 640px) {
  .format-grid { grid-template-columns: repeat(2, 1fr); }
}
.format-block {
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 1.25rem 1.35rem;
  box-shadow: var(--shadow);
}
.format-block h3 { margin: 0 0 0.75rem; font-size: 1rem; }
.format-block ul {
  margin: 0;
  padding-left: 1.1rem;
  color: var(--muted);
  font-size: 0.92rem;
}
.format-block li { margin-bottom: 0.35rem; }
.format-block strong { color: var(--text); }

/* FAQ */
.faq-list { display: grid; gap: 0.65rem; }
.faq-item {
  background: var(--bg);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 0.15rem 1rem;
}
.faq-item summary {
  cursor: pointer;
  font-weight: 600;
  padding: 0.9rem 0;
  list-style: none;
}
.faq-item summary::-webkit-details-marker { display: none; }
.faq-item summary::after {
  content: "+";
  float: right;
  color: var(--primary);
  font-weight: 700;
}
.faq-item[open] summary::after { content: "–"; }
.faq-item p {
  margin: 0 0 1rem;
  color: var(--muted);
  font-size: 0.92rem;
}

/* CTA strip */
.cta-strip {
  background: linear-gradient(135deg, var(--primary-deep), var(--accent));
  color: #fff;
  padding: 3rem 0;
}
.cta-inner {
  display: flex;
  flex-direction: column;
  gap: 1.5rem;
  align-items: flex-start;
}
@media (min-width: 800px) {
  .cta-inner {
    flex-direction: row;
    align-items: center;
    justify-content: space-between;
  }
}
.cta-strip h2 { margin: 0 0 0.5rem; font-size: 1.45rem; color: #fff; }
.cta-strip p { margin: 0; opacity: 0.92; font-size: 0.95rem; }
.cta-note { margin-top: 0.5rem !important; font-size: 0.8rem !important; opacity: 0.8 !important; }
.cta-note code { background: rgba(255,255,255,0.2); color: #fff; }
.cta-actions { display: flex; flex-wrap: wrap; gap: 0.75rem; flex-shrink: 0; }
.cta-strip .btn-primary {
  background: #fff;
  color: var(--primary-deep) !important;
}
.cta-strip .btn-primary:hover { background: var(--primary-soft); }

/* Footer */
.site-footer {
  background: #0b1f3a;
  color: #a8c0e0;
  padding: 2rem 0 2.5rem;
  font-size: 0.85rem;
}
.footer-inner { display: grid; gap: 0.75rem; }
.footer-inner > div {
  display: flex;
  flex-wrap: wrap;
  gap: 0.5rem 1rem;
  align-items: baseline;
}
.footer-inner strong { color: #fff; font-size: 0.95rem; }
.footer-inner p { margin: 0; line-height: 1.5; }
.footer-meta { opacity: 0.75; font-size: 0.8rem; }


/* Signup form */
.signup-section { background: var(--surface); border-top: 1px solid var(--border); border-bottom: 1px solid var(--border); }
.inner.narrow { max-width: 640px; }
.signup-form { margin-top: 1.5rem; display: grid; gap: 1rem; }
.form-row { display: grid; gap: 0.35rem; }
.form-row label, .form-row legend { font-weight: 600; font-size: 0.9rem; color: var(--text); }
.form-row input[type="text"],
.form-row input[type="tel"],
.form-row input[type="email"],
.form-row textarea,
.signup-form select {
  width: 100%;
  padding: 0.7rem 0.85rem;
  border: 1px solid var(--border);
  border-radius: 10px;
  font: inherit;
  background: #fff;
  color: var(--text);
}
.form-row input:focus,
.form-row textarea:focus {
  outline: 2px solid var(--primary-soft);
  border-color: var(--primary);
}
.form-grid-2 { display: grid; gap: 1rem; }
@media (min-width: 640px) {
  .form-grid-2 { grid-template-columns: 1fr 1fr; }
}
.radio-row { display: flex; flex-wrap: wrap; gap: 1rem; }
.radio-row label { font-weight: 500; display: flex; align-items: center; gap: 0.4rem; }
.check-row { display: flex; gap: 0.55rem; align-items: flex-start; font-size: 0.9rem; line-height: 1.45; }
.check-row input { margin-top: 0.2rem; }
.form-hint { margin: 0; font-size: 0.85rem; color: var(--muted); }
.form-status {
  margin: 0;
  padding: 0.75rem 1rem;
  border-radius: 10px;
  background: var(--primary-soft);
  color: var(--primary-deep);
  font-size: 0.95rem;
}
.form-status.error { background: #fee2e2; color: #991b1b; }
.btn-lg { padding: 0.85rem 1.4rem; font-size: 1rem; }
fieldset.form-row { border: 0; padding: 0; margin: 0; }

.section-lead { margin: 0.5rem 0 0; color: var(--muted); max-width: 40rem; line-height: 1.6; }
.radio-row { display: flex; flex-wrap: wrap; gap: 1rem; }
.radio-row label { font-weight: 500; display: inline-flex; align-items: center; gap: 0.4rem; }