/* Responsive rebuild: keeps the 3-column + banner + button-nav + gallery vibe */

:root{
  --page-max: 1100px;
  --gap: 1rem;
  --border: 1px solid rgba(0,0,0,.18);
  --shadow: 0 6px 18px rgba(0,0,0,.10);
  --radius: 10px;
  --bg: #f4f4f4;
  --panel: #ffffff;
  --text: #1a1a1a;
  --muted: #5a5a5a;
  --nav: #e9e9e9;
  --nav-hover: #dcdcdc;
}

*{ box-sizing: border-box; }
html, body{ height: 100%; }
body{
  margin: 0;
  font-family: system-ui, -apple-system, Segoe UI, Roboto, Arial, sans-serif;
  line-height: 1.55;
  color: var(--text);
  background: var(--bg);
}

/* a11y */
.skip-link{
  position: absolute;
  left: -999px;
  top: 0;
  background: #000;
  color: #fff;
  padding: .5rem .75rem;
  z-index: 9999;
}
.skip-link:focus{ left: .75rem; top: .75rem; }

/* header + banner */
.site-header{
  max-width: var(--page-max);
  margin: 0 auto;
  padding: 1rem var(--gap) 0;
}
.banner{
  height: 80px;
  border-radius: var(--radius);
  background: linear-gradient(135deg, rgba(0,0,0,.18), rgba(0,0,0,.05));
  border: var(--border);
  box-shadow: var(--shadow);
}

/* button-nav */
.top-nav{
  margin-top: .75rem;
  display: flex;
  flex-wrap: wrap;
  gap: .5rem;
  justify-content: center;
}
.nav-btn{
  display: inline-block;
  text-decoration: none;
  color: var(--text);
  background: var(--nav);
  border: var(--border);
  border-radius: 999px;
  padding: .45rem .8rem;
  font-size: .95rem;
  white-space: nowrap;
}
.nav-btn:hover,
.nav-btn:focus-visible{
  background: var(--nav-hover);
  outline: none;
}

/* 3-column grid */
.page-grid{
  max-width: var(--page-max);
  margin: 1rem auto 0;
  padding: 0 var(--gap);
  display: grid;
  gap: var(--gap);
  grid-template-columns: 220px 1fr 220px;
  align-items: start;
}

/* sidebars */
.sidebar{
  background: var(--panel);
  border: var(--border);
  border-radius: var(--radius);
  box-shadow: var(--shadow);
  padding: .9rem;
}
.link-list{
  list-style: none;
  padding: 0;
  margin: 0 0 .9rem;
}
.link-list a{
  color: var(--text);
  text-decoration: none;
}
.link-list li + li{ margin-top: .35rem; }
.link-list a:hover{ text-decoration: underline; color: #000; }

.thumb-grid{
  display: grid;
  grid-template-columns: 1fr;
  gap: .6rem;
  justify-items: center;
}
.thumb{
  display: inline-block;
  border-radius: 8px;
  overflow: hidden;
  border: var(--border);
  background: #fff;
}
.thumb img{
  display: block;
  max-width: 100%;
  height: auto;
}
.thumb:hover,
.thumb:focus-visible{
  outline: none;
  box-shadow: 0 0 0 3px rgba(0,0,0,.18);
}

/* content */
.content{
  background: var(--panel);
  border: var(--border);
  border-radius: var(--radius);
  box-shadow: var(--shadow);
  padding: 1.1rem 1.2rem;
}
.content h1{
  margin: 0 0 .75rem;
  font-size: clamp(1.35rem, 2.2vw, 1.85rem);
}
.content p{ color: var(--text); margin: 0 0 1rem; }
.splash{ margin: 0 0 1rem; }
.splash img{
  width: 100%;
  height: auto;
  border-radius: 8px;
  border: var(--border);
}

/* footer */
.site-footer{
  max-width: var(--page-max);
  margin: 1rem auto 2rem;
  padding: 0 var(--gap);
  color: var(--muted);
  text-align: center;
}
.site-footer nav{
  background: transparent;
  padding: .75rem 0 .35rem;
}
.site-footer a{
  color: var(--muted);
  text-decoration: none;
}
.site-footer a:hover{ text-decoration: underline; color: #000; }
copyright{ font-size: .9rem; }

/* responsive: stack columns */
@media (max-width: 920px){
  .page-grid{
    grid-template-columns: 1fr;
  }
  .sidebar{
    order: 2;
  }
  .content{
    order: 1;
  }
  .sidebar-right{ order: 3; }
  .thumb-grid{
    grid-template-columns: repeat(4, minmax(0, 1fr));
  }
}

@media (max-width: 560px){
  .thumb-grid{
    grid-template-columns: repeat(2, minmax(0, 1fr));
  }
  .nav-btn{ font-size: .9rem; }
}