:root {
  --bg-top: #fff5eb;
  --bg-bottom: #edf5ff;
  --surface: #ffffff;
  --surface-soft: #fffaf5;
  --text: #1f2430;
  --muted: #5f6676;
  --line: #dfd9d1;
  --line-strong: #c9c0b6;
  --primary: #d66a28;
  --primary-strong: #9f4716;
  --shadow-soft: 0 10px 28px rgba(31, 36, 48, 0.08);
  --radius-lg: 18px;
  --radius-md: 12px;
}

* {
  box-sizing: border-box;
}

html {
  scrollbar-gutter: stable;
}

body {
  margin: 0;
  font-family: "Hiragino Kaku Gothic ProN", "Yu Gothic", "Noto Sans JP", sans-serif;
  color: var(--text);
  background:
    radial-gradient(980px 420px at 0% -10%, rgba(214, 106, 40, 0.17) 0%, rgba(214, 106, 40, 0) 70%),
    radial-gradient(860px 340px at 110% 12%, rgba(70, 130, 180, 0.16) 0%, rgba(70, 130, 180, 0) 68%),
    linear-gradient(155deg, var(--bg-top) 0%, var(--bg-bottom) 100%);
  min-height: 100vh;
}

.container {
  max-width: 1140px;
  margin: 0 auto;
  padding: 26px 16px 44px;
}

.hero {
  background: linear-gradient(140deg, rgba(255, 255, 255, 0.9) 0%, rgba(255, 249, 242, 0.98) 60%);
  border: 1px solid rgba(201, 192, 182, 0.76);
  border-radius: 22px;
  padding: 20px 22px;
  box-shadow: var(--shadow-soft);
}

.hero h1 {
  margin: 0;
  font-size: clamp(1.55rem, 1.1rem + 1.3vw, 2.2rem);
}

.hero p {
  margin: 8px 0 0;
  color: var(--muted);
  line-height: 1.55;
}

.hero code,
.hint code,
.preview-meta dd {
  font-family: "SFMono-Regular", "Consolas", "Menlo", monospace;
}

.panel {
  background: linear-gradient(180deg, var(--surface) 0%, var(--surface-soft) 100%);
  border: 1px solid var(--line);
  border-radius: var(--radius-lg);
  padding: 18px;
  margin-top: 16px;
  box-shadow: var(--shadow-soft);
}

.grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
  gap: 14px;
}

.card {
  border: 1px solid var(--line);
  border-radius: var(--radius-md);
  background: #fff;
  padding: 14px;
}

.card h2 {
  margin: 0;
  color: var(--primary-strong);
  font-size: 1.15rem;
}

.hint {
  margin: 6px 0 10px;
  color: var(--muted);
  font-size: 0.93rem;
  line-height: 1.6;
}

.flow-arrow {
  margin-top: 4px;
  text-align: center;
  font-size: 1.3rem;
  line-height: 1;
  color: #6d4a39;
}

input,
button {
  font: inherit;
}

input {
  width: 100%;
  border: 1px solid var(--line-strong);
  border-radius: 10px;
  padding: 9px 10px;
  color: var(--text);
  background: #fff;
}

button {
  border: 0;
  border-radius: 10px;
  padding: 10px 12px;
  font-weight: 700;
  cursor: pointer;
  background: linear-gradient(180deg, #fff3ea 0%, #f7ddd0 100%);
  color: #6c3211;
  box-shadow: 0 2px 8px rgba(31, 36, 48, 0.12);
}

.output {
  margin: 12px 0 0;
  min-height: 42px;
  overflow-x: auto;
  overflow-y: hidden;
  border: 1px solid var(--line);
  border-radius: 10px;
  background: #fff9f4;
  padding: 10px;
  white-space: nowrap;
  line-height: 1.35;
}

.result-tools {
  margin-top: 10px;
  display: flex;
  gap: 8px;
  flex-wrap: wrap;
}

.compact-button {
  height: 34px;
  padding: 6px 10px;
  font-size: 0.9rem;
}

.preview-card {
  display: grid;
  gap: 14px;
}

.preview-checker {
  padding: 14px;
  border-radius: 14px;
  border: 1px solid var(--line);
  background:
    linear-gradient(45deg, #f1ede6 25%, transparent 25%, transparent 75%, #f1ede6 75%, #f1ede6 100%),
    linear-gradient(45deg, #f1ede6 25%, #fff 25%, #fff 75%, #f1ede6 75%, #f1ede6 100%);
  background-size: 24px 24px;
  background-position: 0 0, 12px 12px;
}

.preview-swatch {
  min-height: 180px;
  border-radius: 12px;
  border: 1px solid rgba(31, 36, 48, 0.12);
  background: linear-gradient(135deg, rgba(214, 106, 40, 0.12), rgba(70, 130, 180, 0.12));
}

.preview-meta {
  margin: 0;
  display: grid;
  gap: 10px;
}

.preview-meta div {
  display: grid;
  grid-template-columns: 64px 1fr;
  gap: 12px;
  align-items: baseline;
}

.preview-meta dt {
  font-weight: 700;
  color: #6d4a39;
}

.preview-meta dd {
  margin: 0;
  color: var(--text);
  word-break: break-all;
}

.copy-toast {
  position: fixed;
  left: 50%;
  bottom: 18px;
  transform: translateX(-50%) translateY(8px);
  background: rgba(31, 36, 48, 0.92);
  color: #fff;
  padding: 8px 12px;
  border-radius: 999px;
  font-size: 0.86rem;
  line-height: 1;
  pointer-events: none;
  opacity: 0;
  transition: opacity 160ms ease, transform 160ms ease;
  z-index: 50;
}

.copy-toast.show {
  opacity: 1;
  transform: translateX(-50%) translateY(0);
}

.guide-content ul {
  margin: 10px 0 0;
  padding-left: 20px;
}