/* App shell and top-level shared regions */
.app-shell {
  width: min(100%, var(--reading-width));
  margin: 0 auto;
  padding: var(--shell-padding);
}

#infobar,
#app,
#resultView {
  width: 100%;
}

#app {
  max-width: var(--app-max-width);
  margin: 0 auto;
}

.app-main {
  display: grid;
  gap: var(--section-gap);
}

/* Shared panel treatment */
.panel {
  position: relative;
  overflow: hidden;
  border: var(--border-width) solid var(--color-border);
  border-radius: var(--radius-lg);
  background: var(--color-surface);
}

.panel::after {
  content: "";
  position: absolute;
  inset: var(--border-inset-offset);
  pointer-events: none;
  background: transparent;
  border: var(--border-inset-width) solid color-mix(in srgb, var(--color-border-strong) 80%, transparent);
  border-radius: calc(var(--radius-lg) - var(--border-inset-offset));
  opacity: 1;
}

/* Persistent header / navbar */
.hero {
  display: grid;
  gap: var(--section-gap);
  margin: 0 auto var(--section-gap);
  padding: var(--panel-padding);
}

.heroEyebrow {
  position: relative;
  z-index: 1;
  font-family: var(--font-accent);
  font-size: var(--text-small);
  letter-spacing: 0.2em;
  text-transform: uppercase;
  color: var(--color-highlight);
}

.heroHeading,
.heroNotes {
  position: relative;
  z-index: 1;
}

.heroHeading {
  display: grid;
  gap: var(--space-2);
}

.hero h1 {
  font-size: var(--text-title);
}

.heroLead {
  color: var(--color-text-muted);
  max-width: none;
}

.heroNotes {
  display: grid;
  gap: var(--space-3);
  color: var(--color-text-soft);
}

.toolbarHeader {
  position: relative;
  z-index: 1;
}

.toolbarHeader h2 {
  font-size: var(--text-heading);
}

#navbar {
  display: flex;
  flex-flow: row nowrap;
  justify-content: stretch;
  gap: var(--control-gap);
  padding: 0;
}

.button,
button {
  appearance: none;
  -webkit-appearance: none;
  width: 100%;
  min-height: var(--button-height);
  border: var(--border-width) solid var(--color-border);
  border-radius: var(--radius-pill);
  padding: var(--button-padding-y) var(--button-padding-x);
  cursor: pointer;
  color: var(--color-text);
  font-size: var(--button-text-size);
  font-weight: 700;
  letter-spacing: 0.05em;
  transition: border-color 140ms ease, background-color 140ms ease, color 140ms ease;
}

#navbar .button {
  flex: 1 1 0;
  min-width: 0;
  white-space: nowrap;
  background: var(--color-surface-soft) !important;
  background-image: none !important;
  opacity: 1 !important;
}

.button:hover,
button:hover {
  border-color: var(--color-border-strong);
  background-color: color-mix(in srgb, currentColor 8%, transparent);
}

.button:focus-visible,
button:focus-visible,
textarea:focus-visible,
select:focus-visible,
input[type="checkbox"]:focus-visible,
input[type="range"]:focus-visible {
  outline: 2px solid var(--color-highlight);
  outline-offset: 2px;
}

.button-primary {
  background: color-mix(in srgb, var(--accent1) 70%, var(--accent2));;
  color: color-mix(in srgb, var(--main1) 82%, black);
  border-color: color-mix(in srgb, var(--accent1) 60%, var(--main1));
}

.button-primary:hover {
  border-color: color-mix(in srgb, var(--accent2) 78%, white);
  background-color: color-mix(in srgb, var(--accent2) 88%, white);
}

.button-secondary {
  background: var(--color-surface-soft);
}

.button-ghost {
  background: var(--main1-raised);
}

@media (max-width: 720px) {
  .app-shell {
    padding: var(--shell-padding-mobile);
  }

  .hero {
    padding: var(--panel-padding-mobile);
  }

  #navbar {
    flex-wrap: nowrap;
  }
}

@media (max-width: 520px) {
  .app-shell {
    padding: var(--shell-padding-compact);
  }

  #navbar {
    display: grid;
    grid-template-columns: repeat(2, minmax(0, 1fr));
  }
}