/* Base */
html, body {
  padding: 0;
  margin: 0;
  background: #FFFFFF;
  color: #111111;
  font-family: Inter, system-ui, -apple-system, "Segoe UI", Helvetica, Arial, sans-serif;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
  text-rendering: optimizeLegibility;
}

a {
  color: #1F2937;
  text-decoration: none;
}
a:hover {
  opacity: 0.8;
}

/* Container */
.container {
  max-width: 880px;
  margin: 0 auto;
  padding: 0; /* desktop: no side padding */
}

/* Vertical rhythm helpers */
.section {
  margin-top: 72px;
}
.subsection {
  margin-top: 36px;
}
.stack-16 > * + * { margin-top: 16px; }
.para-24 > * + * { margin-top: 18px; }

/* Typography */
h1 {
  font-size: 48px;
  font-weight: 600;
  letter-spacing: -0.02em;
  line-height: 1.15;
  margin: 0 0 24px 0;
  padding-top: 120px;
  color: #111111;
}

h2 {
  font-size: 28px;
  font-weight: 600;
  line-height: 1.25;
  margin: 72px 0 18px 0;
  color: #111111;
}

h3 {
  font-size: 20px;
  font-weight: 600;
  margin: 36px 0 12px 0;
  color: #111111;
}

p, li {
  font-size: 17px;
  line-height: 1.65;
  color: #444444;
  margin: 0 0 0 0;
}

.muted, .muted p, .muted li {
  font-size: 16px;
  line-height: 1.65;
  color: #777777;
}

/* Avoid visual drama */
strong { font-weight: 600; }
em { font-style: normal; }

/* Divider */
.divider {
  height: 1px;
  background: #EAEAEA;
  margin: 72px 0; /* spacing above and below dividers */
}

/* Top Nav */
.topbar {
  position: sticky;
  top: 0;
  background: #FFFFFF;
  border-bottom: 1px solid #E5E7EB;
  z-index: 50;
}
.topbar-inner {
  max-width: 880px;
  margin: 0 auto;
  padding: 14px 0 14px 0; /* desktop: no horizontal padding */
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 16px;
}
.brand {
  display: flex;
  align-items: baseline;
  gap: 10px;
  white-space: nowrap;
}
.brand-mark {
  font-weight: 600;
  letter-spacing: -0.02em;
  color: #111111;
}
.brand-sub {
  font-size: 14px;
  color: #6B7280;
  line-height: 1.2;
}


/* Hamburger Menu & Drawer */
:root {
  --bg: #fff;
  --border: #E5E7EB;
  --primary-soft: #F3F4F6;
  --text: #111;
  --muted-text: #6B7280;
}

.menu-btn{
  appearance:none;
  border:1px solid var(--border);
  background:var(--bg);
  border-radius:10px;
  padding:10px 12px;
  cursor:pointer;
  display:flex;
  align-items:center;
  gap:10px;
}
.menu-btn:focus{outline:2px solid var(--primary-soft); outline-offset:2px}
.hamburger{
  width:18px;
  height:12px;
  display:inline-block;
  position:relative;
}
.hamburger span{
  position:absolute;
  left:0;
  right:0;
  height:2px;
  background:var(--text);
  border-radius:2px;
}
.hamburger span:nth-child(1){top:0}
.hamburger span:nth-child(2){top:5px}
.hamburger span:nth-child(3){top:10px}
.menu-label{
  font-size:13px;
  color:var(--muted-text);
}

/* Drawer */
.drawer-overlay{
  position:fixed;
  inset:0;
  background:rgba(11,18,32,0.22);
  display:none;
  z-index:20;
}
.drawer{
  position:fixed;
  top:0;
  right:0;
  height:100%;
  width:min(360px, 92vw);
  background:var(--bg);
  border-left:1px solid var(--border);
  transform:translateX(100%);
  transition:transform 180ms ease;
  z-index:30;
  display:flex;
  flex-direction:column;
}
.drawer.open{transform:translateX(0)}
.drawer-overlay.open{display:block}
.drawer-header{
  padding:16px 16px 10px;
  border-bottom:1px solid var(--border);
  display:flex;
  align-items:center;
  justify-content:space-between;
}
.drawer-title{
  font-weight:650;
}
.drawer-close{
  appearance:none;
  border:1px solid var(--border);
  background:var(--bg);
  border-radius:50%;
  width:32px;
  height:32px;
  display:flex;
  align-items:center;
  justify-content:center;
  font-size:20px;
  color:var(--text);
  cursor:pointer;
  transition:background 0.15s;
}
.drawer-close:hover, .drawer-close:focus {
  background:var(--primary-soft);
}
.drawer-nav{
  padding:10px 8px 16px;
}
.nav-list{
  list-style:none;
  padding:0;
  margin:0;
}
.nav-list a{
  display:flex;
  align-items:center;
  justify-content:space-between;
  padding:12px 12px;
  border-radius:10px;
  color:var(--text);
}
.nav-list a:hover{
  background:var(--primary-soft);
  text-decoration:none;
}
.nav-list a[aria-current="page"]{
  background:var(--primary-soft);
  border:1px solid var(--border);
}

/* Slide panel (shadow allowed here only) */
.panel-overlay {
  position: fixed;
  inset: 0;
  background: rgba(17, 17, 17, 0.20);
  display: none;
  z-index: 60;
}
.panel {
  position: fixed;
  top: 0;
  right: 0;
  height: 100%;
  width: 320px;
  max-width: 86vw;
  background: #FFFFFF;
  border-left: 1px solid #EAEAEA;
  transform: translateX(100%);
  z-index: 70;
  display: flex;
  flex-direction: column;
  border-radius: 8px 0 0 8px;
}
.panel-header {
  padding: 16px;
  border-bottom: 1px solid #E5E7EB;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 12px;
}
.panel-title {
  font-size: 14px;
  font-weight: 600;
  color: #111111;
  margin: 0;
}
.panel-close {
  font-size: 14px;
  color: #1F2937;
  border: 1px solid #E5E7EB;
  background: #FFFFFF;
  padding: 8px 10px;
  border-radius: 6px;
  cursor: pointer;
}
.panel-links {
  padding: 8px 16px;
  display: flex;
  flex-direction: column;
  gap: 6px;
}
.panel-links a {
  font-size: 14px;
  color: #111111;
  padding: 14px 12px; /* approx 52px item height */
  border-radius: 8px;
  border: 1px solid #EAEAEA;
  text-decoration: none;
  font-weight: 500;
}
.panel-links a.is-active {
  color: #111111;
  font-weight: 600;
  border-color: #1F2937;
}

body.panel-open .panel-overlay { display: block; }
body.panel-open .panel { transform: translateX(0); }

/* Hero */
.hero {
  margin-top: 0;
}
.logo {
  max-width: 100%;
  height: auto;
  max-height: 160px;
  display: block;
  margin: 0 0 24px 0;
  padding-top: 120px;
}
.hero-anchor {
  font-size: 18px;
  font-weight: 500;
  margin: 24px 0 0 0;
  color: #111111;
  line-height: 1.35;
}
.hero-stacked {
  margin: 24px 0 0 0;
  padding-left: 22px;
  list-style: disc;
}
.hero-stacked li {
  margin: 0;
  padding: 0;
  font-size: 18px;
  line-height: 1.35;
  color: #444444;
}
.hero-stacked li + li { margin-top: 12px; }

/* Authority Axiom Block */
.axiom {
  border-left: 4px solid #1F2937;
  padding-left: 18px;
  margin: 48px 0;
  font-weight: 500;
  font-size: 18px;
  line-height: 1.45;
  color: #111111;
}

/* Lists */
ul.bullets {
  margin: 0;
  padding-left: 22px;
  list-style: disc;
}
ul.bullets li {
  font-size: 16px;
  font-weight: 500;
  color: #444444;
}
ul.bullets li + li {
  margin-top: 12px;
}

/* Diagram */
.diagram {
  margin: 24px 0 0 0;
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 14px;
}
.box {
  background: #FFFFFF;
  border: 1px solid #E5E7EB;
  padding: 20px;
  border-radius: 6px;
  width: 100%;
  max-width: 520px;
  text-align: center;
  color: #111111;
  font-size: 16px;
  line-height: 1.5;
}
.arrow {
  color: #1F2A44;
  font-size: 18px;
  line-height: 1;
  user-select: none;
}
.arrow-note {
  font-size: 14px;
  color: #6B7280;
  margin-top: 6px;
}

/* Footer */
footer {
  border-top: 1px solid #EAEAEA;
  padding: 36px 0 36px 0; /* bottom spacing 36px */
  margin-top: 72px; /* spacing above divider */
}
.footer-inner {
  max-width: 880px;
  margin: 0 auto;
  display: flex;
  flex-direction: column;
  gap: 12px;
  text-align: center;
  align-items: center;
}
.footer-links {
  display: flex;
  gap: 24px;
  flex-wrap: wrap;
}
.footer-links a {
  font-size: 14px;
  color: #777777;
  text-decoration: none;
}
.footer-note {
  font-size: 14px;
  color: #777777;
  line-height: 1.6;
  margin: 0;
  max-width: 680px;
}

/* Responsive */

@media (max-width: 720px) {
  .container {
    margin: 0 auto;
    padding: 0 24px; /* mobile horizontal padding */
  }
  h1 {
    font-size: 40px;
    padding-top: 80px;
  }
  .logo {
    padding-top: 80px;
  }
  h2 {
    font-size: 28px;
    margin-top: 56px;
  }
  p, li { font-size: 17px; }

  .section { margin-top: 56px; }
  .subsection { margin-top: 28px; }
  .divider { margin: 56px 0; }
}

@media (max-width: 480px) {
  h1 {
    font-size: 34px;
    padding-top: 60px;
  }
  .logo {
    padding-top: 60px;
  }
}