.reader-layout {
  position: relative;
  min-height: 100vh;
  padding-top: 64px;
}

.reader-topbar {
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 12px 18px;
  background: color-mix(in srgb, var(--bg), transparent 10%);
  backdrop-filter: blur(10px);
  border-bottom: 1px solid var(--border);
  z-index: 10;
  transition: transform 0.2s ease;
}

.reader-topbar.hidden {
  transform: translateY(-110%);
}

.topbar-group {
  display: flex;
  align-items: center;
  gap: 10px;
}

.h-scroll {
  width: min(360px, 40vw);
  vertical-align: middle;
}

.reader-main {
  display: grid;
  gap: 20px;
  width: min(1200px, 94vw);
  margin: 0 auto;
  padding: 24px 0 48px;
}

@media (min-width: 960px) {
  .reader-main {
    grid-template-columns: 240px 1fr;
    align-items: start;
  }
}

.toc {
  position: sticky;
  top: 84px;
  background: var(--panel);
  border: 1px solid var(--border);
  border-radius: 16px;
  padding: 16px;
  max-height: calc(100vh - 120px);
  overflow: auto;
}

.toc h3 {
  font-size: 16px;
  margin-bottom: 12px;
}

.toc ul {
  list-style: none;
  display: grid;
  gap: 8px;
}

.toc button {
  width: 100%;
  text-align: left;
  background: transparent;
  color: var(--text);
  border: 1px solid transparent;
  padding: 8px 10px;
  border-radius: 10px;
  cursor: pointer;
}

.toc button:hover {
  border-color: var(--border);
  background: color-mix(in srgb, var(--panel), #000 6%);
}

.reader-content {
  background: var(--panel);
  border: 1px solid var(--border);
  border-radius: 18px;
  padding: 24px;
  min-height: 70vh;
  overflow-x: auto;
  overflow-y: hidden;
  column-width: 100vw;
  column-gap: 0;
  scroll-snap-type: x mandatory;
  font-size: calc(var(--font-size) * 1%);
  line-height: var(--line-height);
  letter-spacing: var(--letter-spacing);
}

.reader-content > * {
  scroll-snap-align: start;
}

.reader-title {
  font-size: 18px;
  font-weight: 600;
}

.tap-zone {
  position: fixed;
  inset: 0;
  z-index: 5;
  background: transparent;
  pointer-events: none;
}

.settings-panel {
  position: fixed;
  top: 0;
  right: 0;
  width: min(320px, 92vw);
  height: 100vh;
  background: var(--panel);
  border-left: 1px solid var(--border);
  box-shadow: -10px 0 30px rgba(0, 0, 0, 0.25);
  padding: 20px;
  transform: translateX(100%);
  transition: transform 0.2s ease;
  z-index: 20;
  display: grid;
  gap: 14px;
}

.settings-panel.open {
  transform: translateX(0);
}

.settings-panel header {
  display: flex;
  align-items: center;
  justify-content: space-between;
}

.settings-panel .field {
  display: grid;
  gap: 6px;
}

.settings-panel input[type="range"] {
  width: 100%;
}

.settings-panel select {
  width: 100%;
  padding: 8px 10px;
  border-radius: 8px;
  border: 1px solid var(--border);
  background: transparent;
  color: var(--text);
}