*, *::before, *::after { box-sizing: border-box; }
html, body { margin: 0; padding: 0; height: 100%; }
body {
  font-family: var(--font);
  font-size: var(--text-base);
  line-height: 1.55;
  background: var(--bg);
  color: var(--ink);
  -webkit-font-smoothing: antialiased;
}
a { color: var(--accent); text-decoration: none; }
a:hover { text-decoration: underline; }
.skip-link {
  position: absolute; left: -9999px; z-index: 9999;
  padding: var(--space-2) var(--space-4);
  background: var(--siemens); color: #000;
}
.skip-link:focus { left: var(--space-4); top: var(--space-4); }

#app { min-height: 100vh; }
#app.landing-mode { display: block; }

.shell {
  display: grid;
  grid-template-columns: var(--sidebar-w) 1fr;
  min-height: 100vh;
}
@media (max-width: 900px) {
  .shell { grid-template-columns: 1fr; }
  .sidebar { display: none; }
  .sidebar.open { display: flex; position: fixed; inset: 0; z-index: 200; width: min(280px, 85vw); }
}

.sidebar {
  background: var(--bg-elevated);
  border-right: 1px solid var(--border);
  display: flex;
  flex-direction: column;
  padding: var(--space-4);
  overflow-y: auto;
}
.sidebar-brand {
  display: flex;
  align-items: center;
  gap: var(--space-3);
  width: 100%;
  margin: 0 0 var(--space-3);
  padding: var(--space-2) var(--space-3);
  border: 1px solid var(--border);
  border-radius: var(--radius-sm);
  background: linear-gradient(135deg, rgba(0, 150, 150, 0.12) 0%, rgba(0, 190, 220, 0.06) 100%);
  color: var(--ink);
  text-decoration: none;
  cursor: pointer;
  transition: border-color var(--transition), background var(--transition), box-shadow var(--transition);
}
.sidebar-brand:hover {
  border-color: rgba(0, 190, 220, 0.45);
  background: linear-gradient(135deg, rgba(0, 150, 150, 0.2) 0%, rgba(0, 190, 220, 0.1) 100%);
  box-shadow: 0 4px 16px rgba(0, 0, 0, 0.25);
  text-decoration: none;
}
.sidebar-brand:focus-visible {
  outline: 2px solid var(--siemens-bright);
  outline-offset: 2px;
}
.sidebar-brand-icon {
  flex-shrink: 0;
  color: var(--siemens-bright);
  line-height: 0;
}
.sidebar-brand-lockup {
  display: flex;
  flex-direction: column;
  align-items: flex-start;
  gap: 2px;
  min-width: 0;
}
.sidebar-brand-line {
  display: flex;
  align-items: baseline;
  flex-wrap: wrap;
  gap: 0.2em;
  font-size: var(--text-sm);
  font-weight: 700;
  line-height: 1.2;
  letter-spacing: 0.03em;
}
.brand-hedera { color: var(--siemens-bright); }
.brand-x {
  color: var(--ink-muted);
  font-weight: 500;
  font-size: 0.85em;
}
.brand-siemens { color: var(--ink); }
.sidebar-brand-tag {
  font-size: 9px;
  font-weight: 600;
  text-transform: uppercase;
  letter-spacing: 0.14em;
  color: var(--ink-muted);
}
.sidebar-progress {
  font-size: var(--text-xs);
  color: var(--ink-muted);
  margin-bottom: var(--space-4);
}
.progress-ring {
  height: 4px;
  background: var(--panel);
  border-radius: 2px;
  overflow: hidden;
  margin-top: var(--space-2);
}
.progress-ring-fill {
  height: 100%;
  background: linear-gradient(90deg, var(--siemens), var(--siemens-bright));
  transition: width var(--transition);
}
.nav-list { list-style: none; margin: 0; padding: 0; flex: 1; }
.nav-list li { margin-bottom: 2px; }
.nav-list a {
  display: flex;
  align-items: center;
  gap: var(--space-2);
  padding: var(--space-2) var(--space-3);
  border-radius: var(--radius-sm);
  color: var(--ink-muted);
  font-size: var(--text-sm);
  text-decoration: none;
  transition: background var(--transition), color var(--transition);
}
.nav-list a:hover { background: var(--panel); color: var(--ink); text-decoration: none; }
.nav-list a.active { background: rgba(0, 150, 150, 0.15); color: var(--siemens-bright); }
.nav-list a.done::before {
  content: "✓";
  font-size: 10px;
  color: var(--success);
  width: 14px;
}
.sidebar-footer {
  margin-top: auto;
  padding-top: var(--space-4);
  border-top: 1px solid var(--border);
  font-size: var(--text-xs);
  color: var(--ink-dim);
}
.sidebar-controls { display: flex; flex-wrap: wrap; gap: var(--space-2); margin-top: var(--space-3); }
.sidebar-controls label { font-size: var(--text-xs); color: var(--ink-muted); display: flex; align-items: center; gap: 4px; cursor: pointer; }

.main {
  display: flex;
  flex-direction: column;
  min-width: 0;
}
.topbar {
  height: var(--header-h);
  border-bottom: 1px solid var(--border);
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 0 var(--space-5);
  background: rgba(11, 29, 46, 0.92);
  backdrop-filter: blur(8px);
  position: sticky;
  top: 0;
  z-index: 50;
}
.topbar-title { font-size: var(--text-lg); font-weight: 600; }
.topbar-actions { display: flex; gap: var(--space-3); align-items: center; }
.menu-toggle { display: none; background: none; border: 1px solid var(--border); color: var(--ink); padding: 6px 10px; border-radius: var(--radius-sm); cursor: pointer; }
@media (max-width: 900px) { .menu-toggle { display: block; } }

.content {
  flex: 1;
  padding: var(--space-5) var(--space-6) var(--space-8);
  max-width: 1100px;
}
.content.presenter { font-size: 1.12em; max-width: 1200px; }

.watermark {
  position: fixed;
  bottom: calc(64px + var(--space-2));
  right: var(--space-4);
  font-size: 10px;
  color: var(--ink-dim);
  letter-spacing: 0.15em;
  text-transform: uppercase;
  pointer-events: none;
  opacity: 0.5;
}

.landing-page {
  min-height: 100vh;
  display: flex;
  flex-direction: column;
  background: linear-gradient(160deg, #061018 0%, var(--bg) 40%, #0a2838 100%);
}
.landing-hero {
  flex: 1;
  display: flex;
  flex-direction: column;
  justify-content: center;
  padding: var(--space-8) var(--space-6);
  max-width: 720px;
  margin: 0 auto;
  text-align: center;
}
.landing-eyebrow {
  font-size: var(--text-xs);
  text-transform: uppercase;
  letter-spacing: 0.2em;
  color: var(--siemens-bright);
  margin-bottom: var(--space-4);
}
.landing-title {
  font-size: clamp(var(--text-xl), 5vw, var(--text-2xl));
  font-weight: 700;
  line-height: 1.15;
  margin: 0 0 var(--space-4);
}
.landing-subtitle { color: var(--ink-muted); font-size: var(--text-lg); margin-bottom: var(--space-5); }
.landing-message {
  background: var(--panel);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: var(--space-4) var(--space-5);
  margin-bottom: var(--space-6);
  font-size: var(--text-lg);
  border-left: 3px solid var(--siemens);
}
.landing-ctas { display: flex; flex-wrap: wrap; gap: var(--space-3); justify-content: center; }
.landing-footer {
  text-align: center;
  padding: var(--space-4);
  font-size: var(--text-xs);
  color: var(--ink-dim);
}