:root {
  --bg: #0f1115;
  --surface: #171a21;
  --surface-2: #1f2430;
  --border: #2a2f3a;
  --text: #e7e9ee;
  --muted: #8b93a3;
  --accent: #4f8cff;
  --accent-hover: #6fa1ff;
  --danger: #ef5a5a;
  --success: #35c07a;
  --radius: 10px;
}

* { box-sizing: border-box; }

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

a { color: var(--accent); text-decoration: none; }
a:hover { color: var(--accent-hover); }

.container {
  max-width: 960px;
  margin: 0 auto;
  padding: 32px 20px 64px;
}

.topnav {
  display: flex;
  align-items: center;
  gap: 24px;
  padding: 14px 24px;
  background: var(--surface);
  border-bottom: 1px solid var(--border);
  flex-wrap: wrap;
}
.topnav .brand { font-weight: 700; color: var(--text); }
.nav-links { display: flex; gap: 16px; flex: 1; flex-wrap: wrap; }
.nav-links a { color: var(--muted); padding: 4px 0; border-bottom: 2px solid transparent; }
.nav-links a.active, .nav-links a:hover { color: var(--text); border-color: var(--accent); }
.nav-user { display: flex; align-items: center; gap: 10px; color: var(--muted); font-size: 14px; }

h1 { font-size: 1.6rem; margin: 0 0 6px; }
h2 { font-size: 1.1rem; margin: 0 0 6px; }
.muted { color: var(--muted); }
.small { font-size: 0.85rem; }

.grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(220px, 1fr));
  gap: 16px;
  margin: 20px 0;
}

.card {
  display: block;
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 18px;
  color: var(--text);
}
.card:hover { border-color: var(--accent); }
.card p { color: var(--muted); font-size: 0.92rem; margin: 6px 0 12px; }
.card-cta { font-size: 0.85rem; color: var(--accent); }
.card-muted { opacity: 0.7; }
.card-muted .card-cta { color: var(--muted); }

.section-head {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 12px;
  margin-top: 28px;
}

.panel {
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 18px;
  margin-top: 20px;
}

.list-overview { list-style: none; padding: 0; margin: 10px 0; }
.list-overview li {
  padding: 10px 0;
  border-bottom: 1px solid var(--border);
}
.list-overview a { display: flex; justify-content: space-between; gap: 10px; color: var(--text); }

.stack { display: flex; flex-direction: column; gap: 12px; max-width: 360px; }
.stack label { display: flex; flex-direction: column; gap: 6px; font-size: 0.9rem; color: var(--muted); }

input[type=text], input[type=password], select, textarea {
  background: var(--surface-2);
  border: 1px solid var(--border);
  color: var(--text);
  border-radius: 8px;
  padding: 9px 11px;
  font-size: 0.95rem;
  font-family: inherit;
}
input:focus, select:focus, textarea:focus { outline: 2px solid var(--accent); outline-offset: 1px; }

.btn {
  display: inline-block;
  background: var(--surface-2);
  border: 1px solid var(--border);
  color: var(--text);
  padding: 9px 16px;
  border-radius: 8px;
  font-size: 0.9rem;
  cursor: pointer;
}
.btn:hover { border-color: var(--accent); }
.btn-primary { background: var(--accent); border-color: var(--accent); color: #05070c; font-weight: 600; }
.btn-primary:hover { background: var(--accent-hover); }
.btn-small { padding: 6px 12px; font-size: 0.82rem; }
.btn.danger, .linklike.danger { color: var(--danger); }

.linklike {
  background: none; border: none; color: var(--muted); cursor: pointer; padding: 0; font-size: 0.85rem;
  text-decoration: underline;
}
.linklike:hover { color: var(--text); }

.inline-form { display: flex; gap: 10px; margin: 14px 0; flex-wrap: wrap; }
.inline-form input[type=text] { flex: 1; min-width: 200px; }
.inline { display: inline; }

.auth-card {
  max-width: 360px;
  margin: 60px auto;
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 28px;
}

.flash { padding: 10px 14px; border-radius: 8px; margin-bottom: 16px; font-size: 0.9rem; }
.flash-error { background: rgba(239,90,90,0.12); color: #ff8f8f; border: 1px solid rgba(239,90,90,0.3); }
.flash-info { background: rgba(79,140,255,0.12); color: #9dc0ff; border: 1px solid rgba(79,140,255,0.3); }

.table { width: 100%; border-collapse: collapse; margin: 14px 0; }
.table th, .table td { text-align: left; padding: 8px 10px; border-bottom: 1px solid var(--border); font-size: 0.9rem; }
.table th { color: var(--muted); font-weight: 600; }

.todo-list { list-style: none; padding: 0; margin: 16px 0; }
.todo-item {
  display: flex;
  align-items: center;
  gap: 12px;
  padding: 10px 0;
  border-bottom: 1px solid var(--border);
}
.todo-item.done .todo-text { color: var(--muted); text-decoration: line-through; }
.todo-text { flex: 1; }
.checkbox {
  width: 22px; height: 22px; border-radius: 6px; border: 1px solid var(--border);
  background: var(--surface-2); color: var(--success); cursor: pointer; flex-shrink: 0;
  display: flex; align-items: center; justify-content: center; font-size: 0.85rem;
}

.format-tool {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 16px;
  margin-top: 18px;
}
@media (max-width: 700px) {
  .format-tool { grid-template-columns: 1fr; }
}
.format-col-head {
  display: flex;
  justify-content: space-between;
  align-items: center;
  margin-bottom: 8px;
  font-size: 0.85rem;
  color: var(--muted);
}
.format-box {
  width: 100%;
  min-height: 320px;
  background: var(--surface-2);
  border: 1px solid var(--border);
  border-radius: 8px;
  padding: 14px;
  color: var(--text);
  font-family: ui-monospace, SFMono-Regular, Menlo, monospace;
  font-size: 0.88rem;
  white-space: pre-wrap;
  overflow-y: auto;
}
.format-box:empty:before {
  content: attr(data-placeholder);
  color: var(--muted);
}
textarea.format-box { resize: vertical; }