:root {
  --bg: #1b1f24;
  --bg-soft: #23282f;
  --panel: #20252c;
  --panel-alt: #262c34;
  --border: rgba(255, 255, 255, 0.08);
  --text: #f3f7fb;
  --muted: #9ca9b8;
  --accent: #62c4ff;
  --accent-strong: #31afff;
  --accent-soft: rgba(98, 196, 255, 0.14);
  --shadow: 0 22px 60px rgba(0, 0, 0, 0.28);
  --radius-xl: 24px;
  --radius-lg: 18px;
  --radius-md: 14px;
}

* {
  box-sizing: border-box;
}

body {
  margin: 0;
  min-height: 100vh;
  font-family: "Segoe UI", Tahoma, Geneva, Verdana, sans-serif;
  color: var(--text);
  background:
    radial-gradient(circle at top, rgba(98, 196, 255, 0.08), transparent 28%),
    linear-gradient(180deg, #15181d 0%, var(--bg) 100%);
}

button,
input,
textarea {
  font: inherit;
}

button,
input,
textarea,
dialog {
  color: inherit;
}

.app-shell,
input,
textarea,
button,
.ghost-upload-button {
  -webkit-tap-highlight-color: transparent;
}

.app-shell {
  max-width: 1240px;
  margin: 0 auto;
  padding: max(16px, env(safe-area-inset-top)) max(16px, env(safe-area-inset-right))
    max(24px, env(safe-area-inset-bottom)) max(16px, env(safe-area-inset-left));
}

.topbar {
  display: flex;
  justify-content: space-between;
  align-items: end;
  gap: 20px;
  margin-bottom: 24px;
  position: sticky;
  top: 0;
  z-index: 20;
  padding: 12px 0 8px;
  background: linear-gradient(180deg, rgba(27, 31, 36, 0.96), rgba(27, 31, 36, 0.82));
  backdrop-filter: blur(12px);
}

.eyebrow,
.section-kicker {
  margin: 0 0 8px;
  letter-spacing: 0.14em;
  text-transform: uppercase;
  font-size: 0.75rem;
  color: var(--accent);
  font-weight: 700;
}

.topbar h1,
.hero-panel h2 {
  margin: 0;
  letter-spacing: -0.03em;
}

.topbar h1 {
  max-width: 16ch;
  font-size: clamp(1.9rem, 3vw, 3.25rem);
}

.nav-tabs {
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
}

.nav-tab,
button {
  border: none;
  border-radius: 999px;
  cursor: pointer;
  transition: background-color 140ms ease, transform 140ms ease, color 140ms ease;
}

.nav-tab {
  padding: 12px 18px;
  background: var(--accent-soft);
  color: var(--accent);
  font-weight: 700;
}

.nav-tab.active,
.nav-tab:hover {
  background: var(--accent);
  color: #042033;
}

.main-content {
  display: grid;
}

.view {
  display: none;
  gap: 20px;
}

.view.active {
  display: grid;
}

.panel {
  background: var(--panel);
  border: 1px solid var(--border);
  border-radius: var(--radius-xl);
  box-shadow: var(--shadow);
}

.hero-panel {
  display: grid;
  gap: 18px;
  padding: 28px;
}

.hero-panel p {
  margin: 0;
  max-width: 72ch;
  color: var(--muted);
  line-height: 1.6;
}

.search-row {
  display: grid;
  grid-template-columns: minmax(0, 1fr) auto;
  gap: 12px;
}

input,
textarea {
  width: 100%;
  padding: 14px 16px;
  font-size: 16px;
  border-radius: 14px;
  border: 1px solid var(--border);
  background: var(--panel-alt);
  resize: vertical;
}

input:focus,
textarea:focus {
  outline: 2px solid rgba(98, 196, 255, 0.18);
  border-color: var(--accent);
}

button {
  padding: 14px 18px;
  background: var(--accent);
  color: #062538;
  font-weight: 800;
}

button:hover {
  transform: translateY(-1px);
}

.ghost-button {
  background: transparent;
  color: var(--muted);
  border: 1px solid var(--border);
}

.ghost-upload-button {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  padding: 14px 18px;
  border-radius: 999px;
  background: transparent;
  color: var(--muted);
  border: 1px solid var(--border);
  cursor: pointer;
  transition: background-color 140ms ease, transform 140ms ease, color 140ms ease;
}

.ghost-upload-button:hover {
  background: rgba(255, 255, 255, 0.04);
  color: var(--text);
  transform: translateY(-1px);
}

.ghost-button:hover {
  background: rgba(255, 255, 255, 0.04);
  color: var(--text);
}

.small-button {
  padding: 9px 13px;
  font-size: 0.92rem;
}

.install-row {
  display: flex;
  align-items: center;
  gap: 12px;
  flex-wrap: wrap;
}

.install-status,
.generation-status {
  margin: 0;
  color: var(--muted);
  min-height: 1.4em;
}

.dictionary-layout,
.library-layout {
  display: grid;
  grid-template-columns: minmax(320px, 420px) minmax(0, 1fr);
  gap: 20px;
}

.panel {
  padding: 22px;
}

.panel-header,
.dictionary-card-header,
.document-card-top,
.document-actions,
.button-row,
.library-header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 12px;
}

.stack {
  display: grid;
  gap: 16px;
}

label span {
  display: inline-block;
  margin-bottom: 8px;
  font-weight: 700;
}

.count-pill {
  margin: 0;
  padding: 8px 12px;
  border-radius: 999px;
  background: var(--accent-soft);
  color: var(--accent);
  font-weight: 700;
  white-space: nowrap;
}

.empty-state {
  padding: 16px;
  border-radius: var(--radius-lg);
  background: rgba(255, 255, 255, 0.03);
  color: var(--muted);
}

.card-list,
.library-groups {
  display: grid;
  gap: 14px;
  margin-top: 18px;
}

.dictionary-card,
.document-card,
.subject-group {
  padding: 18px;
  border-radius: var(--radius-lg);
  border: 1px solid var(--border);
  background: var(--panel-alt);
}

.dictionary-card h4,
.document-card h4,
.subject-group h4,
.dictionary-detail h5 {
  margin: 0;
}

.term-category,
.document-meta {
  margin: 6px 0 0;
  color: var(--accent);
  font-weight: 600;
}

.term-description,
.term-explanation,
.term-example,
.document-note {
  margin-bottom: 0;
  color: var(--muted);
  line-height: 1.6;
}

.dictionary-detail {
  margin-top: 16px;
}

.dictionary-detail h5 {
  margin-bottom: 6px;
  font-size: 0.82rem;
  text-transform: uppercase;
  letter-spacing: 0.08em;
  color: var(--accent);
}

.subject-group {
  display: grid;
  gap: 14px;
}

.subject-group-header {
  display: flex;
  justify-content: space-between;
  align-items: baseline;
  gap: 12px;
}

.subject-group-count {
  color: var(--muted);
  font-size: 0.9rem;
}

.hidden {
  display: none;
}

.preview-dialog {
  width: min(1000px, calc(100vw - 32px));
  border: none;
  padding: 0;
  border-radius: var(--radius-xl);
  background: transparent;
}

.preview-dialog::backdrop {
  background: rgba(0, 0, 0, 0.6);
}

.preview-dialog-inner {
  background: #161a1f;
  border-radius: var(--radius-xl);
  padding: 24px;
  min-height: 70vh;
  border: 1px solid var(--border);
}

.preview-content {
  height: calc(70vh - 60px);
  margin-top: 16px;
  border-radius: var(--radius-lg);
  overflow: hidden;
  background: #101418;
  border: 1px solid var(--border);
}

.preview-content iframe {
  width: 100%;
  height: 100%;
  border: none;
}

.preview-fallback {
  display: grid;
  place-items: center;
  height: 100%;
  padding: 24px;
  text-align: center;
  color: var(--muted);
}

.sr-only {
  position: absolute;
  width: 1px;
  height: 1px;
  padding: 0;
  margin: -1px;
  overflow: hidden;
  clip: rect(0, 0, 0, 0);
  border: 0;
}

@media (max-width: 920px) {
  .topbar,
  .dictionary-layout,
  .library-layout {
    grid-template-columns: 1fr;
    display: grid;
    align-items: start;
  }

  .topbar {
    top: max(0px, env(safe-area-inset-top));
  }
}

@media (max-width: 640px) {
  .app-shell {
    padding: 16px;
  }

  .hero-panel,
  .panel {
    padding: 18px;
  }

  .search-row,
  .panel-header,
  .dictionary-card-header,
  .document-card-top,
  .document-actions,
  .button-row,
  .subject-group-header,
  .library-header {
    display: grid;
  }

  .topbar h1 {
    max-width: none;
    font-size: 1.8rem;
  }

  .nav-tabs {
    display: grid;
    grid-template-columns: 1fr 1fr;
    width: 100%;
  }

  .nav-tab,
  button,
  .ghost-upload-button {
    min-height: 48px;
  }

  .install-row {
    display: grid;
    grid-template-columns: 1fr 1fr;
    align-items: stretch;
  }

  .install-status,
  .generation-status {
    grid-column: 1 / -1;
  }

  .count-pill {
    justify-self: start;
  }
}