:root {
  --primary: #dc2626;
  --primary-dark: #b91c1c;
  --ink: #1f2430;
  --muted: #667085;
  --bg: #f7f7f9;
  --card: #ffffff;
  --border: #e5e7eb;
  --success-bg: #ecfdf3;
  --success-text: #036b26;
  --error-bg: #fef3f2;
  --error-text: #b42318;
  --radius: 12px;
}

* { box-sizing: border-box; }

body {
  margin: 0;
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, Helvetica, Arial, sans-serif;
  background: var(--bg);
  color: var(--ink);
  line-height: 1.5;
}

.container { max-width: 1100px; margin: 0 auto; padding: 0 20px; }

.topbar { background: var(--card); border-bottom: 1px solid var(--border); position: sticky; top: 0; z-index: 10; }
.topbar-inner { display: flex; align-items: center; justify-content: space-between; height: 64px; }
.brand { font-weight: 700; font-size: 1.15rem; color: var(--ink); text-decoration: none; display: flex; align-items: center; gap: 8px; }
.brand-icon { font-size: 1.3rem; }
.topnav a { margin-left: 20px; color: var(--muted); text-decoration: none; font-size: 0.92rem; }
.topnav a:hover { color: var(--primary); }

.page { padding: 36px 20px 60px; min-height: 60vh; }

.hero { text-align: center; margin-bottom: 36px; }
.hero h1 { font-size: 2.1rem; margin-bottom: 8px; }
.hero p { color: var(--muted); font-size: 1.05rem; max-width: 640px; margin: 0 auto; }

.tool-search { max-width: 480px; margin: 24px auto 0; }
.tool-search input {
  width: 100%; padding: 12px 16px; border-radius: 999px; border: 1px solid var(--border);
  font-size: 0.95rem; outline: none;
}
.tool-search input:focus { border-color: var(--primary); }

.category { margin-top: 40px; }
.category h2 { font-size: 1.1rem; text-transform: uppercase; letter-spacing: 0.04em; color: var(--muted); margin-bottom: 14px; }

.grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(220px, 1fr));
  gap: 16px;
}

.tool-card {
  background: var(--card);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 18px;
  text-decoration: none;
  color: var(--ink);
  display: block;
  transition: transform .12s ease, box-shadow .12s ease, border-color .12s ease;
}
.tool-card:hover { transform: translateY(-2px); box-shadow: 0 8px 20px rgba(0,0,0,0.06); border-color: #d1d5db; }
.tool-card .icon { font-size: 1.6rem; display: block; margin-bottom: 10px; }
.tool-card h3 { margin: 0 0 4px; font-size: 1.02rem; }
.tool-card p { margin: 0; font-size: 0.85rem; color: var(--muted); }
.tool-card.disabled { opacity: 0.5; cursor: not-allowed; }
.badge { display: inline-block; font-size: 0.68rem; padding: 2px 8px; border-radius: 999px; background: #eef2ff; color: #3730a3; margin-left: 6px; vertical-align: middle; }
.badge.warn { background: #fff7ed; color: #9a3412; }

.card {
  background: var(--card);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 28px;
  max-width: 720px;
  margin: 0 auto;
}
.card h1 { margin-top: 0; font-size: 1.5rem; }
.card .tool-desc { color: var(--muted); margin-bottom: 24px; }

.field { margin-bottom: 18px; }
.field label { display: block; font-weight: 600; margin-bottom: 6px; font-size: 0.92rem; }
.field .hint { color: var(--muted); font-size: 0.82rem; margin-top: 4px; }

input[type=file], input[type=text], input[type=number], input[type=password], select, textarea {
  width: 100%; padding: 10px 12px; border: 1px solid var(--border); border-radius: 8px;
  font-size: 0.95rem; font-family: inherit; background: #fff; color: var(--ink);
}
textarea { resize: vertical; min-height: 90px; }
input[type=range] { width: 100%; }

.row { display: flex; gap: 14px; flex-wrap: wrap; }
.row .field { flex: 1; min-width: 160px; }

.checkbox-row { display: flex; align-items: center; gap: 8px; margin-bottom: 12px; }
.checkbox-row input { width: auto; }

.btn {
  display: inline-block; background: var(--primary); color: #fff; border: none;
  padding: 12px 22px; border-radius: 8px; font-size: 0.95rem; font-weight: 600;
  cursor: pointer; text-decoration: none;
}
.btn:hover { background: var(--primary-dark); }
.btn-sm { padding: 8px 14px; font-size: 0.85rem; }
.btn-secondary { background: #fff; color: var(--ink); border: 1px solid var(--border); }
.btn-secondary:hover { background: #f3f4f6; }

.alert { padding: 14px 16px; border-radius: 10px; margin-bottom: 20px; font-size: 0.92rem; }
.alert-success { background: var(--success-bg); color: var(--success-text); }
.alert-error { background: var(--error-bg); color: var(--error-text); }
.alert-info { background: #eff6ff; color: #1d4ed8; }

.footer { border-top: 1px solid var(--border); padding: 24px 0; margin-top: 40px; }
.footer p { color: var(--muted); font-size: 0.82rem; text-align: center; }

.file-drop {
  border: 2px dashed var(--border); border-radius: 10px; padding: 26px; text-align: center;
  cursor: pointer; transition: border-color .12s ease, background .12s ease;
}
.file-drop.dragover { border-color: var(--primary); background: #fef2f2; }
.file-drop .file-list { margin-top: 10px; font-size: 0.85rem; color: var(--muted); text-align: left; }

.spinner-overlay {
  display: none; position: fixed; inset: 0; background: rgba(255,255,255,0.75);
  align-items: center; justify-content: center; z-index: 50; flex-direction: column; gap: 12px;
}
.spinner-overlay.active { display: flex; }
.spinner { width: 42px; height: 42px; border: 4px solid #e5e7eb; border-top-color: var(--primary); border-radius: 50%; animation: spin 0.8s linear infinite; }
@keyframes spin { to { transform: rotate(360deg); } }

.back-link { display: inline-block; margin-bottom: 18px; color: var(--muted); text-decoration: none; font-size: 0.88rem; }
.back-link:hover { color: var(--primary); }

table.info-table { width: 100%; border-collapse: collapse; margin-top: 10px; }
table.info-table td { padding: 8px 10px; border-bottom: 1px solid var(--border); font-size: 0.9rem; }
table.info-table td:first-child { color: var(--muted); width: 40%; }