:root {
  --bg: #f7f8fa;
  --surface: #ffffff;
  --line: #e6e8ee;
  --text: #111827;
  --muted: #6b7280;
  --accent: #111827;
  --sidebar-width: 280px;
}

* { box-sizing: border-box; }
html { scrollbar-gutter: stable; }

body {
  margin: 0;
  background: var(--bg);
  color: var(--text);
  font: 16px/1.55 Georgia, "Times New Roman", serif;
}

.app-layout {
  min-height: 100vh;
}

.sidebar {
  position: fixed;
  inset: 0 auto 0 0;
  width: var(--sidebar-width);
  background: var(--surface);
  border-right: 1px solid var(--line);
  padding: 26px 16px;
  overflow-y: auto;
  z-index: 10;
}

.sidebar .brand {
  display: block;
  margin: 0 0 18px;
  text-decoration: none;
  color: var(--text);
  font: 700 40px/1.1 "Segoe UI", Arial, sans-serif;
  letter-spacing: -0.02em;
}

.side-nav {
  display: flex;
  flex-direction: column;
  gap: 6px;
}

.side-link {
  display: block;
  min-height: 40px;
  padding: 10px 12px;
  border: 0;
  border-left: 3px solid transparent;
  border-radius: 10px;
  color: #1f2937;
  text-decoration: none;
  font: 600 14px/1.2 Arial, sans-serif;
  transition: background-color .15s ease, color .15s ease;
}

.side-link:hover {
  background: #f3f4f6;
}

.side-link.is-active {
  background: transparent;
  color: #111827;
  border-left: 3px solid #111827;
  padding-left: 9px;
}

.side-item {
  display: flex;
  flex-direction: column;
  gap: 6px;
}

.side-item-head {
  display: grid;
  grid-template-columns: 1fr auto;
  gap: 6px;
  align-items: center;
}

.side-toggle {
  border: 0;
  background: transparent;
  color: #475569;
  border-radius: 8px;
  width: 26px;
  height: 26px;
  line-height: 1;
  padding: 0;
  cursor: pointer;
  font-size: 14px;
}

.side-item.is-open .side-toggle {
  color: #111827;
  transform: rotate(180deg);
}

.side-submenu {
  display: none;
  margin-left: 8px;
  padding-left: 10px;
  border-left: 2px solid #eceff5;
  flex-direction: column;
  gap: 4px;
}

.side-submenu.is-open {
  display: flex;
}

.side-sublink {
  min-height: 36px;
  padding: 8px 10px;
  font-size: 13px;
  font-weight: 600;
}

.content-area {
  margin-left: var(--sidebar-width);
  min-height: 100vh;
  padding: 28px;
}

.content-shell {
  max-width: 1160px;
}

.content-shell > * + * {
  margin-top: 12px;
}

.section-card,
.post-card,
.article {
  background: var(--surface);
  border: 1px solid var(--line);
  border-radius: 14px;
  padding: 18px;
}

.section-card > :first-child,
.post-card > :first-child,
.article > :first-child {
  margin-top: 0 !important;
}

.section-card > :last-child,
.post-card > :last-child,
.article > :last-child {
  margin-bottom: 0 !important;
}

.hero h1 {
  margin: 0;
  font: 700 36px/1.1 "Segoe UI", Arial, sans-serif;
}

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

.post-card h2 {
  margin: 0 0 8px;
  font: 700 24px/1.2 "Segoe UI", Arial, sans-serif;
}

.post-card a {
  text-decoration: none;
  color: var(--text);
}

time {
  color: var(--muted);
  font-size: 13px;
}

.article h1 {
  margin: 0 0 8px;
  font: 700 32px/1.15 "Segoe UI", Arial, sans-serif;
}

.back,
.admin-link {
  color: var(--accent);
  text-decoration: none;
  font-family: Arial, sans-serif;
}

.admin-link {
  border: 1px solid var(--line);
  border-radius: 999px;
  padding: 6px 12px;
  background: #fff;
  font: 600 13px/1 Arial, sans-serif;
}

.content-shell a:not(.btn):not(.side-link):not(.brand):not(.admin-link) {
  color: #c81e1e;
}

.content-shell a:not(.btn):not(.side-link):not(.brand):not(.admin-link):hover {
  color: #a41515;
}

.post-card h3 a,
.post-card h2 a,
.post-card .h5 a {
  color: var(--text) !important;
}

.post-card h3 a:hover,
.post-card h2 a:hover,
.post-card .h5 a:hover {
  color: #0f172a !important;
}

.alert-wrap .alert,
.alert {
  border: 1px solid var(--line);
  background: #fff;
  border-radius: 10px;
  padding: 8px 10px;
  margin: 0 0 8px;
  font-family: Arial, sans-serif;
  font-size: 14px;
}

.form p {
  margin: 0 0 10px;
}

.form input,
textarea {
  width: 100%;
  border: 1px solid var(--line);
  border-radius: 10px;
  padding: 9px 10px;
  font: 15px/1.4 Arial, sans-serif;
  background: #fff;
}

button,
.btn {
  display: inline-block;
  border: 1px solid var(--line);
  border-radius: 10px;
  padding: 8px 12px;
  text-decoration: none;
  color: var(--text);
  background: #fff;
  font: 600 14px/1 Arial, sans-serif;
  cursor: pointer;
}

.actions {
  display: flex;
  gap: 8px;
  flex-wrap: wrap;
  margin-top: 12px;
}

.qr {
  max-width: 320px;
  width: 100%;
  display: block;
  margin: 10px 0;
  border: 1px solid var(--line);
  border-radius: 10px;
}

@media (max-width: 900px) {
  .sidebar {
    position: static;
    width: auto;
    border-right: 0;
    border-bottom: 1px solid var(--line);
    padding: 12px;
  }

  .content-area {
    margin-left: 0;
    padding: 12px;
  }
}