:root {
  --dev-bg: #f4f7f4;
  --dev-surface: rgba(255, 255, 255, 0.86);
  --dev-surface-strong: #ffffff;
  --dev-text: #18201c;
  --dev-muted: #607066;
  --dev-border: #cad8cf;
  --dev-accent: #245946;
  --dev-accent-strong: #173d30;
  --dev-accent-soft: rgba(36, 89, 70, 0.12);
  --dev-highlight: #dcece4;
  --dev-shadow: 0 1.5rem 3rem rgba(20, 36, 28, 0.08);
  --dev-radius: 1.5rem;
}

:root[data-theme="dark"] {
  --dev-bg: #101927;
  --dev-surface: rgba(25, 35, 53, 0.84);
  --dev-surface-strong: #182336;
  --dev-text: #f3f7fc;
  --dev-muted: #c3cddd;
  --dev-border: #33455f;
  --dev-accent: #7fb4a0;
  --dev-accent-strong: #5b8d7c;
  --dev-accent-soft: rgba(127, 180, 160, 0.16);
  --dev-highlight: #24364b;
  --dev-shadow: 0 1.6rem 3rem rgba(0, 0, 0, 0.35);
}

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

html {
  color-scheme: light;
}

:root[data-theme="dark"] {
  color-scheme: dark;
}

body {
  margin: 0;
  background:
    linear-gradient(rgba(36, 89, 70, 0.04) 1px, transparent 1px),
    linear-gradient(90deg, rgba(36, 89, 70, 0.04) 1px, transparent 1px),
    radial-gradient(circle at top left, rgba(186, 221, 204, 0.45), transparent 30%),
    linear-gradient(180deg, #fbfdfb 0%, var(--dev-bg) 100%);
  background-size: 1.5rem 1.5rem, 1.5rem 1.5rem, auto, auto;
  color: var(--dev-text);
  font-family:
    "Noto Sans JP",
    "Hiragino Sans",
    "Yu Gothic",
    sans-serif;
  line-height: 1.7;
}

:root[data-theme="dark"] body {
  background:
    linear-gradient(rgba(127, 180, 160, 0.06) 1px, transparent 1px),
    linear-gradient(90deg, rgba(127, 180, 160, 0.06) 1px, transparent 1px),
    radial-gradient(circle at top left, rgba(64, 92, 138, 0.28), transparent 30%),
    linear-gradient(180deg, #132033 0%, var(--dev-bg) 100%);
}

a {
  color: inherit;
}

a:focus-visible,
button:focus-visible,
textarea:focus-visible,
input:focus-visible {
  outline: none;
  box-shadow:
    0 0 0 0.125rem rgba(10, 132, 255, 0.9),
    0 0 0 0.35rem rgba(10, 132, 255, 0.22);
}

.dev-shell {
  width: min(72rem, calc(100% - 2rem));
  margin: 0 auto;
  padding: 1.5rem 0 4.5rem;
}

.dev-topbar {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 1rem;
  padding: 0 0 1.4rem;
}

.dev-brand {
  display: inline-flex;
  align-items: center;
  gap: 0.65rem;
  text-decoration: none;
  font-family:
    ui-monospace,
    SFMono-Regular,
    Menlo,
    Consolas,
    monospace;
  font-size: 1rem;
  font-weight: 700;
  letter-spacing: 0.08em;
  text-transform: uppercase;
}

.dev-brand__dot {
  width: 0.9rem;
  height: 0.9rem;
  border-radius: 0.25rem;
  background: linear-gradient(135deg, var(--dev-accent) 0%, #5d8f7a 100%);
  box-shadow: 0 0 0 0.35rem var(--dev-accent-soft);
}

.dev-backlink {
  display: inline-flex;
  align-items: center;
  gap: 0.45rem;
  padding: 0.72rem 1.05rem;
  border: 1px solid var(--dev-border);
  border-radius: 0.85rem;
  background: color-mix(in srgb, var(--dev-surface-strong) 78%, transparent);
  text-decoration: none;
  color: var(--dev-muted);
  font-size: 0.88rem;
  font-weight: 700;
  letter-spacing: 0.06em;
  text-transform: uppercase;
  transition:
    background-color 0.16s ease,
    border-color 0.16s ease,
    color 0.16s ease;
}

.dev-backlink:hover {
  background: var(--dev-surface-strong);
  border-color: var(--dev-accent);
  color: var(--dev-text);
}

.dev-page-backlink {
  margin: 0 0 1rem;
}

.dev-page-backlink a {
  display: inline-flex;
  align-items: center;
  gap: 0.45rem;
  padding: 0.72rem 1.05rem;
  border: 1px solid var(--dev-border);
  border-radius: 0.85rem;
  background: color-mix(in srgb, var(--dev-surface-strong) 78%, transparent);
  color: var(--dev-muted);
  text-decoration: none;
  font-size: 0.88rem;
  font-weight: 700;
  letter-spacing: 0.06em;
  text-transform: uppercase;
  transition:
    background-color 0.16s ease,
    border-color 0.16s ease,
    color 0.16s ease;
}

.dev-page-backlink a:hover {
  background: var(--dev-surface-strong);
  border-color: var(--dev-accent);
  color: var(--dev-text);
}

.dev-card {
  background: var(--dev-surface);
  border: 1px solid var(--dev-border);
  border-radius: var(--dev-radius);
  box-shadow: var(--dev-shadow);
  backdrop-filter: blur(14px);
}

.dev-hero {
  position: relative;
  overflow: hidden;
  padding: clamp(1.9rem, 3vw, 3.25rem);
}

.dev-hero::before {
  content: "";
  position: absolute;
  inset: 0;
  background:
    radial-gradient(circle at top right, rgba(36, 89, 70, 0.15), transparent 30%),
    linear-gradient(135deg, rgba(255, 255, 255, 0.4), transparent 60%);
  pointer-events: none;
}

:root[data-theme="dark"] .dev-hero::before {
  background:
    radial-gradient(circle at top right, rgba(127, 180, 160, 0.14), transparent 30%),
    linear-gradient(135deg, rgba(255, 255, 255, 0.03), transparent 60%);
}

.dev-eyebrow {
  position: relative;
  margin: 0;
  color: var(--dev-accent);
  font-family:
    ui-monospace,
    SFMono-Regular,
    Menlo,
    Consolas,
    monospace;
  font-size: 0.82rem;
  font-weight: 700;
  letter-spacing: 0.12rem;
  text-transform: uppercase;
}

.dev-hero h1 {
  position: relative;
  margin: 0.75rem 0 1rem;
  font-family:
    ui-monospace,
    SFMono-Regular,
    Menlo,
    Consolas,
    monospace;
  font-size: clamp(2rem, 4.6vw, 3.35rem);
  line-height: 1.08;
  letter-spacing: -0.04em;
}

.dev-lead {
  position: relative;
  max-width: 46rem;
  margin: 0;
  color: var(--dev-muted);
  font-size: clamp(1rem, 2vw, 1.1rem);
  line-height: 1.85;
}

.dev-section {
  margin-top: 1.6rem;
  padding: clamp(1.3rem, 2.5vw, 2.15rem);
}

.dev-grid {
  display: grid;
  gap: 1rem;
  grid-template-columns: repeat(auto-fit, minmax(14rem, 1fr));
}

.dev-linkcard {
  display: block;
  position: relative;
  padding: 1.15rem 1.2rem 1.2rem;
  border: 1px solid color-mix(in srgb, var(--dev-accent) 24%, var(--dev-border));
  border-radius: 1.15rem;
  background: var(--dev-surface-strong);
  text-decoration: none;
  transition:
    border-color 0.16s ease,
    box-shadow 0.16s ease,
    transform 0.16s ease;
}

.dev-linkcard:hover {
  border-color: color-mix(in srgb, var(--dev-accent) 56%, var(--dev-border));
  box-shadow: 0 1rem 1.8rem rgba(20, 36, 28, 0.09);
  transform: translateY(-0.16rem);
}

.dev-linkcard::after {
  content: "";
  position: absolute;
  inset: auto 1.2rem 0.95rem auto;
  width: 0.65rem;
  height: 0.65rem;
  border-top: 2px solid color-mix(in srgb, var(--dev-accent) 72%, transparent);
  border-right: 2px solid color-mix(in srgb, var(--dev-accent) 72%, transparent);
  transform: rotate(45deg);
}

.dev-linkcard__eyebrow {
  margin: 0 0 0.55rem;
  color: var(--dev-accent);
  font-size: 0.74rem;
  font-weight: 700;
  letter-spacing: 0.14em;
  text-transform: uppercase;
}

.dev-linkcard h2,
.dev-linkcard h3 {
  margin: 0;
  max-width: calc(100% - 1.5rem);
  font-size: 1.16rem;
  line-height: 1.42;
  letter-spacing: -0.02em;
}

.dev-linkcard p {
  margin: 0.65rem 0 0;
  color: var(--dev-muted);
  font-size: 0.94rem;
  line-height: 1.7;
}

.dev-note {
  margin-top: 0.9rem;
  color: var(--dev-muted);
  font-size: 0.92rem;
}

.dev-meta {
  display: inline-flex;
  align-items: center;
  gap: 0.45rem;
  margin-top: 1rem;
  padding: 0.55rem 0.8rem;
  border: 1px solid color-mix(in srgb, var(--dev-accent) 28%, var(--dev-border));
  border-radius: 999px;
  background: color-mix(in srgb, var(--dev-accent) 10%, transparent);
  color: var(--dev-accent);
  font-size: 0.9rem;
}

.dev-tool h1 {
  margin: 0.75rem 0 0.7rem;
  font-size: clamp(1.95rem, 4vw, 2.9rem);
  line-height: 1.1;
}

.dev-tool__lead {
  margin: 0;
  color: var(--dev-muted);
  max-width: 44rem;
  font-size: 1.02rem;
}

.dev-toolbar {
  display: flex;
  flex-wrap: wrap;
  gap: 0.75rem;
  align-items: center;
  justify-content: space-between;
  margin-bottom: 1.25rem;
}

.dev-button,
.dev-button-secondary {
  appearance: none;
  border: 1px solid transparent;
  border-radius: 999px;
  padding: 0.78rem 1.2rem;
  font: inherit;
  font-weight: 700;
  cursor: pointer;
  transition:
    transform 0.16s ease,
    box-shadow 0.16s ease,
    background-color 0.16s ease,
    border-color 0.16s ease;
}

.dev-button {
  background: linear-gradient(135deg, var(--dev-accent) 0%, var(--dev-accent-strong) 100%);
  color: #fff;
  box-shadow: 0 0.9rem 1.6rem rgba(41, 95, 78, 0.18);
}

.dev-button:hover {
  transform: translateY(-0.0625rem);
}

.dev-button-secondary {
  background: var(--dev-surface-strong);
  color: var(--dev-text);
  border-color: var(--dev-border);
}

.dev-button-secondary:hover {
  border-color: var(--dev-accent);
}

.dev-textarea,
.dev-input,
.dev-output {
  width: 100%;
  border: 1px solid var(--dev-border);
  border-radius: 1rem;
  background: color-mix(in srgb, var(--dev-surface-strong) 96%, transparent);
  color: var(--dev-text);
  font: inherit;
}

.dev-textarea,
.dev-input {
  padding: 1rem 1.05rem;
}

.dev-textarea {
  min-height: 12rem;
  resize: vertical;
}

.dev-output {
  padding: 0.85rem 1rem;
  white-space: pre-wrap;
  word-break: break-word;
  font-family:
    ui-monospace,
    SFMono-Regular,
    Menlo,
    Consolas,
    monospace;
  font-size: 0.9rem;
  line-height: 1.65;
  background: linear-gradient(
    180deg,
    color-mix(in srgb, var(--dev-surface-strong) 98%, transparent) 0%,
    color-mix(in srgb, var(--dev-surface) 98%, transparent) 100%
  );
}

.dev-output--dense {
  font-size: 0.82rem;
  line-height: 1.8;
}

.dev-label {
  display: block;
  margin-bottom: 0.55rem;
  font-weight: 700;
  font-size: 0.95rem;
}

.dev-form-grid {
  display: grid;
  gap: 1rem;
  grid-template-columns: minmax(0, 1.1fr) minmax(0, 1fr);
}

.dev-output-list {
  display: grid;
  gap: 0.9rem;
}

.dev-output-card {
  display: grid;
  gap: 0.55rem;
}

.dev-output-head {
  display: flex;
  justify-content: space-between;
  gap: 1rem;
  align-items: center;
}

.dev-output-head h2,
.dev-output-head h3,
.dev-section h2 {
  margin: 0;
  font-size: 1.1rem;
  line-height: 1.35;
}

.dev-muted {
  color: var(--dev-muted);
}

.dev-preview {
  min-height: 12rem;
  padding: 1rem;
  border: 1px solid var(--dev-border);
  border-radius: 1rem;
  background:
    radial-gradient(circle, color-mix(in srgb, var(--dev-border) 66%, transparent) 1px, rgba(0, 0, 0, 0) 1px),
    color-mix(in srgb, var(--dev-surface-strong) 98%, transparent);
  background-size: 1rem 1rem;
  overflow: auto;
}

.dev-stats {
  display: grid;
  gap: 0.75rem;
  grid-template-columns: repeat(auto-fit, minmax(10rem, 1fr));
}

.dev-stat {
  padding: 0.95rem 1rem;
  border: 1px solid var(--dev-border);
  border-radius: 1rem;
  background: linear-gradient(
    180deg,
    color-mix(in srgb, var(--dev-surface-strong) 98%, transparent) 0%,
    color-mix(in srgb, var(--dev-surface) 98%, transparent) 100%
  );
}

.dev-stat__label {
  margin: 0 0 0.25rem;
  color: var(--dev-muted);
  font-size: 0.84rem;
}

.dev-stat__value {
  margin: 0;
  font-size: 1.2rem;
  font-weight: 700;
}

.dev-stat__value--small {
  font-size: 0.83rem;
  line-height: 1.7;
  word-break: break-word;
}

.dev-copy-state {
  color: var(--dev-accent);
  font-size: 0.84rem;
  font-weight: 700;
}

.dev-footer {
  margin-top: 1.5rem;
  color: var(--dev-muted);
  font-size: 0.9rem;
  text-align: center;
}

.dev-embed {
  width: 100%;
  min-height: min(80vh, 72rem);
  border: 1px solid var(--dev-border);
  border-radius: 1rem;
  background: var(--dev-surface-strong);
}

.dev-fontsize-list {
  display: grid;
  gap: 0.25rem;
}

.dev-fontsize-item {
  padding: 0.3rem 0.45rem;
  border-radius: 0.55rem;
  cursor: pointer;
}

.dev-fontsize-item:hover {
  background: color-mix(in srgb, var(--dev-highlight) 82%, transparent);
}

.dev-inline-code {
  padding: 0.1rem 0.35rem;
  border-radius: 0.35rem;
  background: color-mix(in srgb, var(--dev-accent) 10%, transparent);
  font-family:
    ui-monospace,
    SFMono-Regular,
    Menlo,
    Consolas,
    monospace;
  font-size: 0.92em;
}

@media (max-width: 48rem) {
  .dev-shell {
    width: min(100% - 1rem, 72rem);
  }

  .dev-topbar {
    padding-bottom: 1.05rem;
  }

  .dev-page-backlink {
    margin-bottom: 0.9rem;
  }

  .dev-form-grid {
    grid-template-columns: 1fr;
  }

  .dev-toolbar {
    align-items: stretch;
  }

  .dev-output-head {
    flex-direction: column;
    align-items: flex-start;
  }
}