/* ── Reset & Base ── */
*, *::before, *::after { box-sizing: border-box; margin: 0; padding: 0; }

body {
  font-family: system-ui, -apple-system, sans-serif;
  background: #fff;
  color: #111;
  line-height: 1.6;
}

/* ── Nav ── */
nav {
  padding: 14px 40px;
  border-bottom: 1px solid #e5e5e5;
  font-size: 0.9rem;
}
nav a { color: #444; text-decoration: none; }
nav a:hover { color: #111; text-decoration: underline; }

/* ── Page Header ── */
.page-header {
  background: white;
  border-bottom: 1px solid #e5e5e5;
  padding: 40px 0 32px;
}
.page-header h1 {
  font-size: 1.75rem;
  font-weight: 700;
  margin-bottom: 6px;
}
.subtitle { color: #444; font-size: 1rem; }

/* ── Container ── */
.container {
  max-width: 900px;
  margin: 0 auto;
  padding: 0 40px;
}

/* ── Sections ── */
.section {
  padding: 40px 0 0;
}
.section:last-child { padding-bottom: 60px; }

.section-header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  margin-bottom: 20px;
  flex-wrap: wrap;
  gap: 12px;
}

.section-title {
  font-size: 1.1rem;
  font-weight: 700;
  color: #111;
}

.section-desc {
  color: #444;
  font-size: 0.9rem;
  margin-bottom: 20px;
}

/* ── OS Toggle ── */
.os-toggle {
  display: flex;
  border: 1px solid #e5e5e5;
  border-radius: 8px;
  overflow: hidden;
}
.os-btn {
  padding: 6px 18px;
  font-size: 0.85rem;
  font-family: system-ui, -apple-system, sans-serif;
  background: #fff;
  border: none;
  cursor: pointer;
  color: #444;
  transition: background 0.15s, color 0.15s;
}
.os-btn + .os-btn { border-left: 1px solid #e5e5e5; }
.os-btn.active {
  background: #1a1a1a;
  color: #fff;
}
.os-btn:hover:not(.active) { background: #f8f8f8; }

/* ── Shortcuts Grid ── */
.shortcuts-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 12px;
}

/* ── Shortcut Card ── */
.shortcut-card {
  border: 1px solid #e5e5e5;
  border-radius: 8px;
  padding: 16px;
  cursor: pointer;
  background: #fff;
  text-align: left;
  transition: border-color 0.15s, transform 0.12s, box-shadow 0.12s;
  display: flex;
  flex-direction: column;
  gap: 6px;
  position: relative;
}
.shortcut-card:hover {
  border-color: #2563eb;
  transform: translateY(-2px);
  box-shadow: 0 4px 12px rgba(37,99,235,0.10);
}
.shortcut-card.copied {
  border-color: #16a34a;
  background: #f0fdf4;
}

.shortcut-keys {
  display: flex;
  flex-wrap: wrap;
  gap: 3px;
  align-items: center;
}

kbd {
  font-family: 'Menlo', 'Monaco', monospace;
  font-size: 0.78rem;
  background: #f0f0f0;
  border: 1px solid #ccc;
  border-radius: 4px;
  padding: 2px 6px;
  color: #222;
  display: inline-block;
}

.shortcut-sep {
  font-size: 0.75rem;
  color: #888;
  padding: 0 1px;
}

.shortcut-action {
  font-weight: 600;
  font-size: 0.9rem;
  color: #111;
}

.shortcut-desc {
  font-size: 0.8rem;
  color: #888;
  line-height: 1.4;
}

.copy-flash {
  position: absolute;
  top: 8px;
  right: 10px;
  font-size: 0.72rem;
  color: #16a34a;
  opacity: 0;
  transition: opacity 0.2s;
  pointer-events: none;
}
.shortcut-card.copied .copy-flash { opacity: 1; }

/* ── Extension List ── */
.ext-list {
  display: flex;
  flex-direction: column;
  gap: 12px;
}

.ext-card {
  border: 1px solid #e5e5e5;
  border-radius: 8px;
  padding: 18px 20px;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 16px;
  background: white;
}

.ext-info { flex: 1; }

.ext-name {
  font-weight: 700;
  font-size: 0.95rem;
  margin-bottom: 4px;
}

.ext-desc {
  font-size: 0.85rem;
  color: #444;
}

/* ── Copy Button ── */
.copy-btn {
  font-size: 0.8rem;
  font-family: system-ui, -apple-system, sans-serif;
  padding: 6px 14px;
  border: 1px solid #e5e5e5;
  border-radius: 6px;
  background: #fff;
  color: #444;
  cursor: pointer;
  white-space: nowrap;
  flex-shrink: 0;
  transition: background 0.15s, color 0.15s, border-color 0.15s;
}
.copy-btn:hover { background: #f0f0f0; }
.copy-btn.copied {
  background: #dcfce7;
  border-color: #16a34a;
  color: #16a34a;
}

/* ── Mobile ── */
@media (max-width: 640px) {
  nav { padding: 14px 20px; }
  .container { padding: 0 20px; }
  .shortcuts-grid { grid-template-columns: repeat(2, 1fr); }
  .ext-card { flex-direction: column; align-items: flex-start; }
}

@media (max-width: 480px) {
  .shortcuts-grid { grid-template-columns: 1fr; }
}