/* ===== Wildtw 前台 — Apple 風極簡 ===== */
:root {
  --bg: #ffffff;
  --bg-alt: #f5f5f7;
  --bg-section: #fbfbfd;
  --fg: #1d1d1f;
  --fg-soft: #515154;
  --fg-muted: #86868b;
  --line: #d2d2d7;
  --line-soft: rgba(0,0,0,0.08);
  --blue: #0071e3;
  --blue-hover: #0077ed;
  --green: #29a96e;
  --orange: #f56300;
  --red: #ff3b30;
  --radius: 12px;
  --radius-lg: 18px;
  --radius-pill: 999px;
}

* { box-sizing: border-box; margin: 0; padding: 0; }
html { scroll-behavior: smooth; -webkit-text-size-adjust: 100%; }
body {
  font-family: -apple-system, BlinkMacSystemFont, "SF Pro Display", "SF Pro Text", "Helvetica Neue", "Noto Sans TC", "PingFang TC", sans-serif;
  font-size: 17px;
  line-height: 1.47;
  color: var(--fg);
  background: var(--bg);
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
  letter-spacing: -0.022em;
}
a { color: inherit; text-decoration: none; }
img, svg { display: block; max-width: 100%; }
button { font: inherit; cursor: pointer; }

[data-icon] { display: inline-flex; align-items: center; justify-content: center; line-height: 1; }
[data-icon] > svg { display: block; }

/* ===== Header ===== */
.nav {
  position: sticky; top: 0; z-index: 100;
  background: rgba(255,255,255,0.72);
  backdrop-filter: saturate(180%) blur(20px);
  -webkit-backdrop-filter: saturate(180%) blur(20px);
  border-bottom: 1px solid var(--line-soft);
}
.nav__inner {
  max-width: 980px; margin: 0 auto;
  height: 44px;
  display: flex; align-items: center; justify-content: space-between;
  padding: 0 22px;
  font-size: 14px;
}
.nav__brand { font-weight: 600; font-size: 17px; letter-spacing: -0.02em; }
.nav__brand small { font-weight: 400; color: var(--fg-muted); margin-left: 8px; font-size: 12px; }
.nav__links { display: flex; gap: 0; list-style: none; }
.nav__links a {
  padding: 0 14px; height: 44px;
  display: flex; align-items: center;
  color: var(--fg); opacity: 0.88;
  transition: opacity 0.2s;
}
.nav__links a:hover { opacity: 1; color: var(--blue); }
.nav__util { display: flex; gap: 4px; align-items: center; }
.nav__util a { padding: 4px 12px; }

/* ===== Layout primitives ===== */
.container { max-width: 980px; margin: 0 auto; padding: 0 22px; }
.container--wide { max-width: 1200px; }
.container--narrow { max-width: 720px; }

.section { padding: 100px 0; }
.section--alt { background: var(--bg-alt); }
.section--dark { background: #000; color: #f5f5f7; }
.section--tight { padding: 60px 0; }
.section--loose { padding: 140px 0; }

/* ===== Typography ===== */
.eyebrow {
  font-size: 14px; font-weight: 500;
  color: var(--blue); letter-spacing: 0;
  margin-bottom: 8px;
}
.section--dark .eyebrow { color: #2997ff; }

h1, .h1 {
  font-size: clamp(48px, 6.5vw, 80px);
  font-weight: 600;
  line-height: 1.05;
  letter-spacing: -0.025em;
}
h2, .h2 {
  font-size: clamp(40px, 5vw, 56px);
  font-weight: 600;
  line-height: 1.07;
  letter-spacing: -0.025em;
}
h3, .h3 {
  font-size: 28px;
  font-weight: 600;
  line-height: 1.14;
  letter-spacing: -0.02em;
}
h4, .h4 {
  font-size: 21px;
  font-weight: 600;
  letter-spacing: -0.016em;
}
.lede {
  font-size: clamp(19px, 1.8vw, 24px);
  font-weight: 400;
  color: var(--fg-soft);
  line-height: 1.42;
  letter-spacing: -0.014em;
  max-width: 640px;
}
.meta {
  font-size: 13px;
  color: var(--fg-muted);
  letter-spacing: -0.008em;
}

p { color: var(--fg-soft); }
p + p { margin-top: 16px; }

/* ===== Buttons ===== */
.btn {
  display: inline-flex; align-items: center; justify-content: center;
  gap: 6px; padding: 12px 22px;
  font-size: 17px; font-weight: 400;
  border: none; border-radius: var(--radius-pill);
  background: var(--blue); color: #fff;
  transition: background 0.2s;
  letter-spacing: -0.016em;
  white-space: nowrap;
}
.btn:hover { background: var(--blue-hover); }
.btn--sm { padding: 8px 16px; font-size: 14px; }
.btn--lg { padding: 14px 28px; font-size: 19px; }
.btn--ghost {
  background: transparent; color: var(--blue);
}
.btn--ghost:hover { background: rgba(0,113,227,0.06); }
.btn--outline {
  background: transparent; color: var(--fg);
  border: 1px solid var(--line);
}
.btn--outline:hover { background: var(--bg-alt); }
.btn--dark {
  background: var(--fg); color: #fff;
}
.btn--dark:hover { background: #000; }

.link {
  color: var(--blue);
  display: inline-flex; align-items: center; gap: 4px;
}
.link:hover { text-decoration: underline; }
.link [data-icon] { transition: transform 0.2s; }
.link:hover [data-icon] { transform: translateX(2px); }

/* ===== Forms ===== */
.field { margin-bottom: 20px; }
.label {
  display: block;
  font-size: 12px;
  color: var(--fg-muted);
  margin-bottom: 8px;
  letter-spacing: -0.005em;
}
.input, .select, .textarea {
  width: 100%;
  padding: 14px 16px;
  font-family: inherit; font-size: 17px;
  background: var(--bg-alt);
  border: 1px solid transparent;
  border-radius: var(--radius);
  color: var(--fg);
  transition: border-color 0.15s, background 0.15s;
  letter-spacing: -0.016em;
}
.textarea { resize: vertical; min-height: 80px; }
.input:focus, .select:focus, .textarea:focus {
  outline: none;
  border-color: var(--blue);
  background: #fff;
}
.input::placeholder { color: var(--fg-muted); }

.check {
  display: inline-flex; align-items: flex-start;
  gap: 10px; cursor: pointer; user-select: none;
  font-size: 15px; color: var(--fg-soft);
  line-height: 1.5;
}
.check input[type="checkbox"], .check input[type="radio"] {
  width: 18px; height: 18px;
  accent-color: var(--blue);
  margin-top: 2px;
}

/* ===== Cards / placeholders ===== */
.ph {
  background: var(--bg-alt);
  border-radius: var(--radius);
  display: flex; align-items: center; justify-content: center;
  color: var(--fg-muted); font-size: 13px; letter-spacing: -0.01em;
  position: relative;
}
.ph::after {
  content: ""; position: absolute; inset: 0;
  background:
    repeating-linear-gradient(45deg, transparent 0 8px, rgba(0,0,0,0.018) 8px 9px);
  border-radius: inherit; pointer-events: none;
}

.divider { height: 1px; background: var(--line-soft); margin: 0 auto; max-width: 980px; }

/* ===== Pill (status) ===== */
.pill {
  display: inline-flex; align-items: center; gap: 4px;
  padding: 4px 10px;
  font-size: 12px; font-weight: 500;
  border-radius: var(--radius-pill);
  background: var(--bg-alt); color: var(--fg-soft);
  letter-spacing: 0;
}
.pill--blue { background: rgba(0,113,227,0.1); color: var(--blue); }
.pill--green { background: rgba(41,169,110,0.12); color: var(--green); }
.pill--orange { background: rgba(245,99,0,0.12); color: var(--orange); }
.pill--red { background: rgba(255,59,48,0.12); color: var(--red); }
.pill--dark { background: var(--fg); color: #fff; }

/* ===== Footer ===== */
.footer {
  background: var(--bg-alt);
  padding: 24px 0 16px;
  font-size: 12px; color: var(--fg-muted);
  border-top: 1px solid var(--line-soft);
  letter-spacing: -0.005em;
}
.footer__inner {
  max-width: 980px; margin: 0 auto; padding: 0 22px;
}
.footer__grid {
  display: grid; grid-template-columns: repeat(4, 1fr); gap: 32px;
  padding-bottom: 24px; border-bottom: 1px solid var(--line);
}
.footer__col h5 { font-size: 12px; font-weight: 600; color: var(--fg); margin-bottom: 10px; }
.footer__col ul { list-style: none; }
.footer__col li { padding: 4px 0; }
.footer__col a:hover { text-decoration: underline; }
.footer__legal {
  padding-top: 16px;
  display: flex; justify-content: space-between; align-items: center;
  flex-wrap: wrap; gap: 8px;
}
.footer__legal small { font-family: ui-monospace, SFMono-Regular, monospace; font-size: 11px; }

/* ===== Responsive ===== */
@media (max-width: 768px) {
  .nav__links { display: none; }
  .section { padding: 64px 0; }
  .footer__grid { grid-template-columns: 1fr 1fr; }
}