:root {
  color-scheme: light dark;
  font-family:
    -apple-system, BlinkMacSystemFont, "Hiragino Kaku Gothic ProN",
    "Yu Gothic UI", Meiryo, sans-serif;
  font-size: 16px;
  line-height: 1.5;
  --canvas: #f5f5f7;
  --surface: #ffffff;
  --surface-soft: #f2f2f7;
  --ink: #1d1d1f;
  --secondary: #626269;
  --line: #d8d8de;
  --accent: #0867d8;
  --accent-soft: #e9f2ff;
  --focus: #0a84ff;
  --danger: #b42318;
  --shadow: 0 12px 34px rgba(26, 39, 59, 0.07);
}
* {
  box-sizing: border-box;
}
html {
  scroll-behavior: smooth;
}
body {
  margin: 0;
  color: var(--ink);
  background: var(--canvas);
}
button,
input,
select {
  font: inherit;
}
button,
a {
  -webkit-tap-highlight-color: transparent;
}
a {
  color: var(--accent);
}
a:focus-visible,
button:focus-visible,
select:focus-visible,
input:focus-visible,
[tabindex]:focus-visible {
  outline: 3px solid var(--focus);
  outline-offset: 3px;
}
button:disabled,
select:disabled {
  opacity: 0.55;
  cursor: not-allowed;
}
[hidden] {
  display: none !important;
}
.skip-link {
  position: absolute;
  top: -100px;
  left: 12px;
  z-index: 100;
  padding: 12px 16px;
  border-radius: 12px;
  background: var(--surface);
}
.skip-link:focus {
  top: 12px;
}
.app-header {
  position: relative;
  z-index: 10;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 24px;
  min-height: 74px;
  padding: 10px max(24px, env(safe-area-inset-right)) 10px
    max(24px, env(safe-area-inset-left));
  border-bottom: 1px solid var(--line);
  background: color-mix(in srgb, var(--surface) 88%, transparent);
  backdrop-filter: blur(18px);
}
.app-brand {
  display: flex;
  align-items: center;
  gap: 10px;
  min-height: 44px;
  color: var(--ink);
  font-size: 19px;
  font-weight: 760;
  letter-spacing: -0.02em;
  text-decoration: none;
  white-space: nowrap;
}
.app-brand-mark {
  display: grid;
  place-items: center;
  width: 42px;
  height: 42px;
  border-radius: 12px;
  color: white;
  background: var(--ink);
  font-size: 17px;
  letter-spacing: -0.05em;
}
.app-brand small {
  color: var(--secondary);
  font-size: 12px;
  font-weight: 560;
  letter-spacing: 0;
}
.app-nav {
  display: flex;
  align-items: center;
  gap: 4px;
}
.app-nav a {
  display: grid;
  place-items: center;
  min-height: 44px;
  padding: 8px 15px;
  border-radius: 12px;
  color: var(--secondary);
  font-size: 14px;
  font-weight: 650;
  text-decoration: none;
  white-space: nowrap;
}
.app-nav a:hover {
  background: var(--surface-soft);
  color: var(--ink);
}
.app-nav a[aria-current="page"] {
  color: var(--accent);
  background: var(--accent-soft);
}
.section-kicker {
  margin: 0 0 8px;
  color: var(--accent);
  font-size: 11px;
  font-weight: 760;
  letter-spacing: 0.13em;
}
.primary-button {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 10px;
  min-height: 48px;
  padding: 12px 20px;
  border: 0;
  border-radius: 12px;
  color: #fff;
  background: var(--accent);
  font-weight: 700;
  cursor: pointer;
}
.primary-button:hover {
  filter: brightness(0.94);
}
.error-message {
  color: var(--danger);
}
@media (max-width: 640px) {
  .app-header {
    flex-wrap: wrap;
    gap: 6px 12px;
    padding: 8px max(16px, env(safe-area-inset-right)) 8px
      max(16px, env(safe-area-inset-left));
  }
  .app-brand {
    font-size: 17px;
  }
  .app-nav {
    width: 100%;
    overflow-x: auto;
    justify-content: space-between;
  }
  .app-nav a {
    flex: 1;
    padding-inline: 8px;
  }
}
@media (prefers-color-scheme: dark) {
  :root {
    --canvas: #111114;
    --surface: #1c1c1e;
    --surface-soft: #2c2c2e;
    --ink: #f5f5f7;
    --secondary: #b3b3bb;
    --line: #3a3a3c;
    --accent: #64a9ff;
    --accent-soft: #173049;
    --focus: #79b8ff;
    --danger: #ff8278;
    --shadow: 0 12px 34px rgba(0, 0, 0, 0.25);
  }
  .primary-button {
    color: #071f3c;
  }
  .app-brand-mark {
    color: #111114;
  }
}
@media (prefers-reduced-motion: reduce) {
  html {
    scroll-behavior: auto;
  }
  *,
  *::before,
  *::after {
    animation-duration: 0.01ms !important;
    transition-duration: 0.01ms !important;
  }
}