:root{
  --bg: #0b0c10;
  --panel: #11131a;
  --text: #e7e7ea;
  --muted: #b2b6c2;
  --border: rgba(255,255,255,0.10);
  --link: #7ab7ff;
  --shadow: 0 10px 30px rgba(0,0,0,0.35);
  --radius: 14px;
}

:root[data-theme="light"]{
  --bg: #ffffff;
  --panel: #f6f7fb;
  --text: #11131a;
  --muted: #4c5160;
  --border: rgba(10,20,40,0.12);
  --link: #0b66ff;
  --shadow: 0 10px 30px rgba(20,30,60,0.12);
}

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

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

.container{
  width: min(980px, calc(100% - 32px));
  margin: 0 auto;
}

.site-header{
  position: sticky;
  top: 0;
  z-index: 10;
  background: color-mix(in srgb, var(--bg) 85%, transparent);
  backdrop-filter: blur(10px);
  border-bottom: 1px solid var(--border);
}

.header-row{
  display:flex;
  gap: 16px;
  align-items:center;
  justify-content: space-between;
  padding: 14px 0;
}

.brand{
  font-weight: 700;
  letter-spacing: 0.2px;
  color: var(--text);
}

.nav{
  display:flex;
  gap: 14px;
  flex-wrap: wrap;
  justify-content: center;
}

.nav a{
  padding: 8px 10px;
  border-radius: 10px;
  border: 1px solid transparent;
  color: var(--text);
}
.nav a:hover{
  border-color: var(--border);
  background: color-mix(in srgb, var(--panel) 90%, transparent);
  text-decoration: none;
}

.theme-btn{
  border: 1px solid var(--border);
  background: var(--panel);
  color: var(--text);
  border-radius: 10px;
  padding: 8px 10px;
  cursor: pointer;
  box-shadow: var(--shadow);
}

.hero{
  padding: 30px 0 40px;
}

h1{ margin: 0 0 10px; font-size: 30px; }
h2{ margin: 0 0 6px; font-size: 18px; }
p{ margin: 0 0 12px; }
.muted{ color: var(--muted); }

.grid{
  margin-top: 18px;
  display:grid;
  grid-template-columns: repeat( auto-fit, minmax(220px, 1fr) );
  gap: 14px;
}

.card{
  display:block;
  padding: 16px;
  border-radius: var(--radius);
  background: var(--panel);
  border: 1px solid var(--border);
  box-shadow: var(--shadow);
}
.card:hover{ transform: translateY(-1px); }

.note{
  margin-top: 18px;
  padding: 14px 16px;
  border: 1px solid var(--border);
  background: var(--panel);
  border-radius: var(--radius);
}

.doc{
  padding: 26px 0 50px;
}

.doc h1{ font-size: 28px; margin-bottom: 8px; }
.doc h2{ margin-top: 22px; font-size: 18px; }
.doc ul{ margin: 8px 0 14px 20px; }
.doc li{ margin: 6px 0; }
.box{
  border: 1px solid var(--border);
  background: var(--panel);
  padding: 14px 16px;
  border-radius: var(--radius);
}

.site-footer{
  border-top: 1px solid var(--border);
  padding: 14px 0;
}
.footer-row{
  display:flex;
  justify-content: space-between;
  gap: 12px;
  flex-wrap: wrap;
}