/* level2.css — ワイヤーフレーム: 情報構造の骨格 */

/* ===== Base ===== */
* {
  font-family: system-ui, -apple-system, sans-serif !important;
  box-sizing: border-box;
}

body {
  max-width: 72rem;
  margin: 0 auto;
  padding: 2rem;
  color: #333;
  line-height: 1.5;
  background: #fff;
}

/* ===== ALPS ID labels (hover only) ===== */
[class] {
  position: relative;
}
[class]:hover::after {
  content: "." attr(class);
  position: absolute;
  top: -1.25rem;
  left: 0;
  font-size: 0.5625rem;
  font-family: 'SF Mono', Menlo, Consolas, monospace !important;
  color: #fff;
  background: #555;
  padding: 0.125rem 0.375rem;
  border-radius: 2px;
  white-space: nowrap;
  z-index: 1000;
  pointer-events: none;
  line-height: 1.4;
}

/* ===== Typography: hierarchy by size only ===== */
h1 { font-size: 1.75rem; font-weight: 600; margin: 1rem 0; }
h2 { font-size: 1.25rem; font-weight: 600; margin: 0.75rem 0; }
h3 { font-size: 1rem; font-weight: 600; margin: 0.5rem 0; }
p { margin: 0.375rem 0; }

/* ===== Links: underline only, no color ===== */
a {
  color: #555;
  text-decoration: underline;
}
a:hover {
  color: #222;
}

/* ===== Images: X-box placeholder ===== */
img {
  background: #eee;
  background-image:
    linear-gradient(to top right, transparent calc(50% - 1px), #ccc, transparent calc(50% + 1px)),
    linear-gradient(to top left, transparent calc(50% - 1px), #ccc, transparent calc(50% + 1px));
  min-height: 120px;
  min-width: 100px;
  object-position: -9999px;
}

/* ===== Buttons: base ===== */
button, [type="submit"] {
  border: 1px solid #999;
  background: white;
  padding: 0.5rem 1.5rem;
  color: #333;
  cursor: pointer;
  font-size: 0.875rem;
}
button:hover, [type="submit"]:hover {
  background: #f5f5f5;
}

/* ===== Transition type: left border color ===== */
/* safe = green (read-only, no side effects) */
[class^="go"] button,
[class^="go"] [type="submit"] {
  border-left: 3px solid #00A86B;
}
/* unsafe = red (state-changing, non-idempotent) */
[class^="do"] button,
[class^="do"] [type="submit"] {
  border-left: 3px solid #FF4136;
}
/* idempotent = gold (state-changing, idempotent) */
[data-type="idempotent"] button,
[data-type="idempotent"] [type="submit"] {
  border-left: 3px solid #D4A000;
}

/* ===== Form elements ===== */
input, textarea, select {
  border: 1px solid #ccc;
  padding: 0.375rem 0.5rem;
  background: white;
  font-size: 0.875rem;
}
label {
  display: block;
  font-size: 0.8125rem;
  color: #666;
  margin-top: 0.5rem;
  margin-bottom: 0.125rem;
}

/* ===== Block structure: dashed borders ===== */
section, article, aside {
  border: 1px dashed #ddd;
  padding: 1rem;
  margin: 0.75rem 0;
  position: relative;
}

form {
  border: 1px dashed #c8d8e8;
  padding: 0.75rem;
  margin: 0.5rem 0;
}

/* ===== Header / Footer ===== */
header {
  border-bottom: 2px solid #ccc;
  padding-bottom: 0.75rem;
  margin-bottom: 1.5rem;
}
header > div { display: flex; justify-content: space-between; align-items: center; }

footer {
  border-top: 2px solid #ccc;
  padding-top: 0.75rem;
  margin-top: 2rem;
  font-size: 0.75rem;
  color: #999;
}
nav a {
  margin-right: 1rem;
}

/* ===== Table ===== */
table { border-collapse: collapse; width: 100%; }
th, td { padding: 0.5rem; border: 1px solid #ccc; text-align: left; font-size: 0.875rem; }

/* ===== Definition list ===== */
dl { margin: 0.5rem 0; }
dt { font-weight: 600; margin-top: 0.5rem; font-size: 0.875rem; }
dd { margin-left: 0; color: #555; }

/* ===== Breadcrumb: main > nav:first-child ===== */
main > nav:first-child {
  font-size: 0.8125rem;
  color: #888;
  margin-bottom: 1rem;
}
main > nav:first-child a { color: #666; }
main > nav:first-child > span { margin: 0 0.375rem; }

/* ===== Book grid: article containers ===== */
.Catalog > div,
.Category > div,
section > div {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(180px, 1fr));
  gap: 1rem;
}

/* ===== Cart layout: main > div with section + aside ===== */
.ShoppingCart ~ div {
  display: grid;
  grid-template-columns: 2fr 1fr;
  gap: 1.5rem;
}

/* ===== Emoji covers → X-box in wireframe ===== */
.Book > div:first-child,
article > div:first-child {
  width: 80px;
  height: 100px;
  background: #eee;
  background-image:
    linear-gradient(to top right, transparent calc(50% - 1px), #ccc, transparent calc(50% + 1px)),
    linear-gradient(to top left, transparent calc(50% - 1px), #ccc, transparent calc(50% + 1px));
  font-size: 0;
  display: flex;
  align-items: center;
  justify-content: center;
}