:root{
  --container: 1100px;
  --pad: 18px;
  --text: #111;
  --muted: #666;
  --bg: #fff;
  --line: #e9e9e9;
  --shadow: 0 8px 30px rgba(0,0,0,.08);
}

*{box-sizing:border-box}
body{
  margin:0;
  font-family: system-ui, -apple-system, Segoe UI, Roboto, Arial, sans-serif;
  color:var(--text);
  background:var(--bg);
}
a{color:inherit}
.container{
  max-width: var(--container);
  margin: 0 auto;
  padding: 0 var(--pad);
}

.site-header{
  border-bottom:1px solid var(--line);
  background:var(--bg);
}
.header-top{
  padding: 22px 0 14px;
}
.brand-link{
  text-decoration:none;
}
.brand-text{
  font-size: 28px;
  font-weight: 700;
  letter-spacing:.2px;
}
.brand-subtitle{
  margin-top:6px;
  color:var(--muted);
  font-size: 14px;
}

.nav-wrap{
  border-top:1px solid var(--line);
  border-bottom:1px solid var(--line);
  position: sticky;
  top: 0;
  z-index: 50;
  background: var(--bg);
}
.nav-inner{
  display:flex;
  align-items:center;
  justify-content:space-between;
  min-height: 54px;
}

/* Desktop Nav */
.site-nav{width:100%}
.nav-list{
  list-style:none;
  margin:0;
  padding:0;
  display:flex;
  gap: 18px;
  align-items:center;
}
.nav-item{position:relative}
.nav-link{
  text-decoration:none;
  padding: 12px 6px;
  display:inline-block;
  color: var(--text);
}
.nav-item.is-active > .nav-link{
  font-weight:700;
  border-bottom:2px solid var(--text);
}

.nav-sublist{
  display:none;
  position:absolute;
  top: 100%;
  left:0;
  min-width: 220px;
  background:var(--bg);
  border:1px solid var(--line);
  box-shadow: var(--shadow);
  padding: 8px 0;
  list-style:none;
  margin:0;
}
.nav-item:hover .nav-sublist{display:block}
.nav-subitem{}
.nav-sublink{
  display:block;
  padding: 10px 14px;
  text-decoration:none;
  color: var(--text);
}
.nav-sublink:hover{background:#f7f7f7}

.nav-item--meta{margin-left:auto}
.nav-item--meta + .nav-item--meta{margin-left:0}

/* Toggle button: hidden by default */
.nav-toggle{
  display:none;
  border:1px solid var(--line);
  background: var(--bg);
  border-radius: 10px;
  padding: 10px 12px;
  cursor:pointer;
}
.nav-toggle-lines{
  display:block;
  width: 22px;
  height: 2px;
  background: var(--text);
  position:relative;
}
.nav-toggle-lines::before,
.nav-toggle-lines::after{
  content:"";
  position:absolute;
  left:0;
  width: 22px;
  height: 2px;
  background: var(--text);
}
.nav-toggle-lines::before{top:-7px}
.nav-toggle-lines::after{top:7px}
.sr-only{
  position:absolute;
  left:-9999px;
}

/* Burger mode only when body has .is-scrolled OR small screens */
body.is-scrolled .nav-toggle{display:inline-flex}
body.is-scrolled .site-nav{display:none}

/* Mobile: always burger */
@media (max-width: 820px){
  .nav-toggle{display:inline-flex}
  .site-nav{display:none}
  .nav-item--meta{margin-left:0}
}

/* Open state */
body.nav-open .site-nav{
  display:block;
  width:100%;
}
body.nav-open .nav-list{
  flex-direction:column;
  align-items:flex-start;
  gap:0;
  padding: 10px 0;
}
body.nav-open .nav-link{
  width:100%;
  padding: 12px 0;
}
body.nav-open .nav-sublist{
  position:static;
  box-shadow:none;
  border:0;
  padding:0 0 10px 0;
}
body.nav-open .nav-item:hover .nav-sublist{display:block}

/* Content */
.site-main{padding: 28px 0 40px}
.page-title{margin: 0 0 16px}
.content{line-height:1.65}
.meta{color:var(--muted); margin: 6px 0 18px}

/* Cards */
.cards{
  display:grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 16px;
  margin-top: 18px;
}
.card{
  border:1px solid var(--line);
  border-radius: 14px;
  padding: 16px;
  background: var(--bg);
}
.card-title{margin:0 0 8px; font-size: 18px}
.card-meta{color:var(--muted); font-size: 13px; margin-bottom: 10px}
.card-excerpt{color: #222}

@media (max-width: 980px){
  .cards{grid-template-columns: repeat(2, 1fr)}
}
@media (max-width: 620px){
  .cards{grid-template-columns: 1fr}
}

/* Footer */
.site-footer{
  border-top:1px solid var(--line);
  padding: 22px 0;
  color: var(--muted);
}
.footer-inner{
  display:flex;
  gap: 14px;
  align-items:center;
  justify-content:space-between;
  flex-wrap:wrap;
}
.footer-right a{
  text-decoration:none;
}
.sep{margin: 0 8px; color: #bbb}
.hint{
  margin-top: 18px;
  padding: 12px 14px;
  border: 1px solid var(--line);
  border-radius: 12px;
  color: var(--muted);
}