:root {
  --ink: #14213d;
  --ink-soft: #46516b;
  --line: #dfe5ee;
  --bg: #ffffff;
  --bg-tint: #f4f7fb;
  --brand: #1f5eff;
  --brand-deep: #123a9c;
  --accent: #12b3a6;
  --dark: #0d1730;
  --on-dark: #e7ecf7;
  --radius: 16px;
  --wrap: 1120px;
  --header-h: 64px;
}

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

html {
  scroll-behavior: smooth;
  scroll-padding-top: var(--header-h);
  -webkit-text-size-adjust: 100%;
}

body {
  margin: 0;
  background: var(--bg);
  color: var(--ink);
  font-family: "PingFang TC", "Noto Sans TC", "Microsoft JhengHei", system-ui, -apple-system, sans-serif;
  font-size: 17px;
  line-height: 1.8;
}

h1,
h2,
h3,
p {
  margin: 0;
}

a {
  color: inherit;
}

.wrap {
  width: 100%;
  max-width: var(--wrap);
  margin: 0 auto;
  padding: 0 20px;
}

.narrow {
  max-width: 760px;
}

.center {
  text-align: center;
}

.skip {
  position: absolute;
  left: -9999px;
  top: 0;
  padding: 8px 16px;
  background: var(--ink);
  color: #fff;
  z-index: 20;
}

.skip:focus {
  left: 8px;
  top: 8px;
}

/* Header */
.site-header {
  position: sticky;
  top: 0;
  z-index: 10;
  background: rgba(255, 255, 255, 0.92);
  backdrop-filter: blur(8px);
  border-bottom: 1px solid var(--line);
}

.header-inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 16px;
  min-height: var(--header-h);
}

.brand {
  display: inline-flex;
  align-items: center;
  gap: 10px;
  text-decoration: none;
  font-weight: 700;
  font-size: 18px;
  letter-spacing: 0.04em;
  white-space: nowrap;
}

.brand-mark {
  width: 26px;
  height: 26px;
  border-radius: 8px;
  background: linear-gradient(135deg, var(--brand), var(--accent));
}

.nav {
  display: flex;
  align-items: center;
  gap: 4px;
  font-size: 15px;
}

.nav a {
  padding: 8px 12px;
  border-radius: 999px;
  text-decoration: none;
  color: var(--ink-soft);
  white-space: nowrap;
}

.nav a:hover {
  color: var(--ink);
  background: var(--bg-tint);
}

.nav .nav-cta {
  color: #fff;
  background: var(--brand);
}

.nav .nav-cta:hover {
  color: #fff;
  background: var(--brand-deep);
}

/* Hero */
.hero {
  background: linear-gradient(180deg, var(--bg-tint), var(--bg));
  padding: 56px 0 48px;
}

.hero-inner {
  display: grid;
  gap: 32px;
  align-items: center;
}

.eyebrow {
  color: var(--brand);
  font-size: 14px;
  font-weight: 700;
  letter-spacing: 0.14em;
  margin-bottom: 12px;
}

h1 {
  font-size: clamp(32px, 6.4vw, 54px);
  line-height: 1.3;
  letter-spacing: 0.01em;
}

.accent {
  color: var(--brand);
}

.lead {
  margin-top: 20px;
  color: var(--ink-soft);
  font-size: clamp(16px, 2.2vw, 19px);
  max-width: 34em;
}

.hero-actions {
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
  margin-top: 28px;
}

.btn {
  display: inline-block;
  padding: 12px 24px;
  border-radius: 999px;
  border: 1px solid transparent;
  font-weight: 700;
  font-size: 16px;
  text-decoration: none;
  transition: background-color 0.15s, border-color 0.15s, color 0.15s;
}

.btn-primary {
  background: var(--brand);
  color: #fff;
}

.btn-primary:hover {
  background: var(--brand-deep);
}

.btn-ghost {
  border-color: var(--line);
  background: #fff;
  color: var(--ink);
}

.btn-ghost:hover {
  border-color: var(--brand);
  color: var(--brand);
}

.btn-light {
  background: #fff;
  color: var(--dark);
  word-break: break-all;
}

.btn-light:hover {
  background: var(--on-dark);
}

.hero-art img {
  display: block;
  width: 100%;
  height: auto;
  border-radius: var(--radius);
  box-shadow: 0 20px 48px rgba(20, 33, 61, 0.14);
}

/* Sections */
.section {
  padding: 64px 0;
}

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

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

h2 {
  font-size: clamp(26px, 4.4vw, 36px);
  line-height: 1.4;
}

h3 {
  font-size: 20px;
  line-height: 1.5;
}

.narrow h2 + p,
.narrow p + p {
  margin-top: 18px;
}

.narrow p {
  color: var(--ink-soft);
}

.cards {
  display: grid;
  gap: 20px;
}

.card {
  padding: 28px 24px;
  background: #fff;
  border: 1px solid var(--line);
  border-radius: var(--radius);
}

.card-num {
  display: block;
  color: var(--accent);
  font-weight: 700;
  font-size: 15px;
  letter-spacing: 0.1em;
  margin-bottom: 8px;
}

.card p,
.principles p {
  margin-top: 10px;
  color: var(--ink-soft);
  font-size: 16px;
}

.principles {
  list-style: none;
  margin: 0;
  padding: 0;
  display: grid;
  gap: 24px;
}

.principles li {
  padding-left: 20px;
  border-left: 3px solid var(--brand);
}

.section-dark {
  background: var(--dark);
  color: #fff;
}

.section-dark .eyebrow {
  color: var(--accent);
}

.section-dark p {
  color: var(--on-dark);
}

.section-dark .btn {
  margin-top: 28px;
}

/* Footer */
.site-footer {
  background: var(--dark);
  color: var(--on-dark);
  border-top: 1px solid rgba(255, 255, 255, 0.12);
  font-size: 14px;
}

.footer-inner {
  display: flex;
  flex-wrap: wrap;
  justify-content: space-between;
  gap: 8px 16px;
  padding-top: 20px;
  padding-bottom: 20px;
}

@media (max-width: 640px) {
  .nav a:not(.nav-cta) {
    display: none;
  }
}

@media (min-width: 860px) {
  .hero {
    padding: 96px 0 88px;
  }

  .hero-inner {
    grid-template-columns: 1.15fr 0.85fr;
    gap: 48px;
  }

  .section {
    padding: 96px 0;
  }

  .cards,
  .principles {
    grid-template-columns: repeat(3, 1fr);
  }
}

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