/* 基礎樣式：色票、字型、版面、按鈕。視覺方向依 handoff docs/07（白／淺藍底、深藍字與 CTA）。 */
:root {
  --blue-950: #0b1f4d;
  --blue-900: #12306e;
  --blue-800: #1e40af;
  --blue-700: #1d4ed8;
  --blue-200: #bfdbfe;
  --blue-100: #dbeafe;
  --blue-50: #eff6ff;
  --slate-900: #0f172a;
  --slate-700: #334155;
  --slate-600: #475569;
  --slate-500: #64748b;
  --slate-300: #cbd5e1;
  --slate-200: #e2e8f0;
  --slate-100: #f1f5f9;
  --slate-50: #f8fafc;
  --amber-500: #d97706;
  --amber-800: #92400e;
  --amber-50: #fffbeb;
  --green-700: #15803d;
  --red-700: #b91c1c;
  --white: #ffffff;

  --font-sans: 'Inter', 'Noto Sans TC', 'Microsoft JhengHei', 'PingFang TC', system-ui, sans-serif;
  --container: 1200px;
  --gutter: 16px;
  --radius-sm: 8px;
  --radius: 12px;
  --radius-lg: 20px;
  --shadow-sm: 0 1px 2px rgb(15 23 42 / 0.06);
  --shadow: 0 8px 24px rgb(15 42 95 / 0.08);
  --shadow-lg: 0 20px 48px rgb(15 42 95 / 0.16);
  --header-height: 68px;
  --focus-ring: 0 0 0 3px var(--white), 0 0 0 5px var(--blue-700);
}

*,
*::before,
*::after {
  box-sizing: border-box;
}

html {
  scroll-behavior: smooth;
  scroll-padding-top: calc(var(--header-height) + 16px);
  -webkit-text-size-adjust: 100%;
}

body {
  margin: 0;
  background: var(--white);
  color: var(--slate-700);
  font-family: var(--font-sans);
  font-size: 16px;
  line-height: 1.75;
  -webkit-font-smoothing: antialiased;
}

body.is-locked {
  overflow: hidden;
}

h1,
h2,
h3,
h4 {
  margin: 0 0 0.75rem;
  color: var(--blue-950);
  line-height: 1.3;
  letter-spacing: 0.01em;
}

h1 {
  font-size: clamp(2.125rem, 5vw, 3.5rem);
}

h2 {
  font-size: clamp(1.625rem, 3.2vw, 2.25rem);
}

h3 {
  font-size: 1.1875rem;
}

p {
  margin: 0 0 1rem;
}

a {
  color: var(--blue-700);
}

img,
svg {
  max-width: 100%;
}

:focus-visible {
  outline: none;
  box-shadow: var(--focus-ring);
  border-radius: 6px;
}

.skip-link {
  position: absolute;
  left: 16px;
  top: -48px;
  z-index: 100;
  padding: 8px 16px;
  background: var(--blue-900);
  color: var(--white);
  border-radius: var(--radius-sm);
}

.skip-link:focus {
  top: 12px;
}

.visually-hidden {
  position: absolute;
  width: 1px;
  height: 1px;
  overflow: hidden;
  clip: rect(0 0 0 0);
  white-space: nowrap;
}

.container {
  width: 100%;
  max-width: var(--container);
  margin: 0 auto;
  padding: 0 var(--gutter);
}

.container.narrow {
  max-width: 840px;
}

.section {
  padding: 88px 0;
}

.section.tint {
  background: var(--blue-50);
}

.section.muted {
  background: var(--slate-50);
}

.section-head {
  max-width: 720px;
  margin: 0 auto 48px;
  text-align: center;
}

.section-head p {
  color: var(--slate-600);
  font-size: 1.0625rem;
}

.eyebrow {
  display: inline-block;
  margin-bottom: 12px;
  color: var(--blue-700);
  font-size: 0.875rem;
  font-weight: 700;
  letter-spacing: 0.08em;
}

.lead {
  font-size: 1.125rem;
  color: var(--slate-600);
}

/* 按鈕：主要 CTA 一律 btn-primary，次要 btn-secondary，文字連結 btn-link */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 8px;
  min-height: 44px;
  padding: 10px 20px;
  border: 1.5px solid transparent;
  border-radius: var(--radius-sm);
  font: inherit;
  font-size: 0.9375rem;
  font-weight: 700;
  line-height: 1.2;
  text-decoration: none;
  white-space: nowrap;
  cursor: pointer;
  transition: background-color 0.15s, border-color 0.15s, color 0.15s;
}

.btn-lg {
  min-height: 52px;
  padding: 14px 28px;
  font-size: 1.0625rem;
}

.btn-block {
  width: 100%;
}

.btn-primary {
  background: var(--blue-700);
  color: var(--white);
}

.btn-primary:hover {
  background: var(--blue-800);
}

.btn-secondary {
  background: var(--white);
  border-color: var(--blue-700);
  color: var(--blue-700);
}

.btn-secondary:hover {
  background: var(--blue-50);
}

.btn-ghost {
  background: transparent;
  color: var(--slate-700);
}

.btn-ghost:hover {
  background: var(--slate-100);
}

.btn-link {
  padding: 0;
  min-height: 44px;
  background: none;
  border: 0;
  color: var(--blue-700);
  font-weight: 700;
  text-decoration: underline;
  text-underline-offset: 4px;
}

.btn[disabled] {
  opacity: 0.55;
  cursor: not-allowed;
}

.arrow::after {
  content: '→';
  font-weight: 400;
}

.pending-note {
  display: inline-block;
  padding: 2px 8px;
  border-radius: 999px;
  background: var(--amber-50);
  color: var(--amber-800);
  font-size: 0.8125rem;
  font-weight: 700;
  vertical-align: middle;
}

.fine-print {
  color: var(--slate-500);
  font-size: 0.8125rem;
}

@media (max-width: 720px) {
  .section {
    padding: 64px 0;
  }

  .section-head {
    margin-bottom: 32px;
    text-align: left;
  }

  .btn-lg {
    width: 100%;
  }
}

@media (prefers-reduced-motion: reduce) {
  html {
    scroll-behavior: auto;
  }

  * {
    transition: none !important;
    animation: none !important;
  }
}