:root {
  --bg: #f8f3e8;
  --bg-2: #f1eadb;
  --panel: rgba(255, 255, 255, 0.82);
  --panel-strong: rgba(255, 255, 255, 0.94);
  --line: rgba(56, 68, 58, 0.12);
  --text: #223126;
  --muted: #5f6f64;
  --muted-2: #7f8b80;
  --accent: #ef8e3a;
  --accent-soft: rgba(239, 142, 58, 0.16);
  --accent-2: #93c97a;
  --accent-2-soft: rgba(147, 201, 122, 0.18);
  --warn: #d3a84f;
  --bad: #dc6f63;
  --shadow: 0 22px 50px rgba(93, 74, 38, 0.12);
  --radius: 24px;
  --radius-sm: 16px;
}

* { box-sizing: border-box; }

html { scroll-behavior: smooth; }

body {
  margin: 0;
  color: var(--text);
  font-family: "Noto Sans JP", "Hiragino Sans", "Yu Gothic UI", sans-serif;
  background:
    radial-gradient(circle at 10% 12%, rgba(239, 142, 58, 0.16), transparent 24%),
    radial-gradient(circle at 86% 16%, rgba(147, 201, 122, 0.18), transparent 22%),
    radial-gradient(circle at 50% 100%, rgba(216, 162, 95, 0.12), transparent 26%),
    linear-gradient(180deg, #fbf6ec 0%, #f6f0e3 50%, #f1eadb 100%);
  min-height: 100vh;
}

body::before {
  content: "";
  position: fixed;
  inset: 0;
  pointer-events: none;
  background:
    linear-gradient(135deg, rgba(255, 255, 255, 0.35), transparent 40%),
    radial-gradient(circle at 14% 80%, rgba(239, 142, 58, 0.06), transparent 16%),
    radial-gradient(circle at 82% 26%, rgba(147, 201, 122, 0.06), transparent 18%);
  opacity: 0.9;
}

.app-shell {
  width: min(1280px, calc(100% - 20px));
  margin: 0 auto;
  padding: 16px 0 28px;
  position: relative;
  z-index: 1;
}

.app-layout {
  display: grid;
  grid-template-columns: minmax(230px, 270px) minmax(0, 1fr);
  gap: 16px;
  align-items: start;
}

.app-sidebar,
.view-panel,
.app-footer {
  background: var(--panel);
  border: 1px solid var(--line);
  border-radius: var(--radius);
  box-shadow: var(--shadow);
  backdrop-filter: blur(14px);
}

.app-sidebar {
  position: sticky;
  top: 14px;
  padding: 15px;
}

.sidebar-brand {
  display: flex;
  align-items: center;
  gap: 12px;
  margin-bottom: 12px;
}

.sidebar-logo {
  width: 42px;
  height: 42px;
  border-radius: 12px;
  background: #fff;
  border: 1px solid rgba(56, 68, 58, 0.10);
  box-shadow: 0 8px 16px rgba(93, 74, 38, 0.08);
}

.eyebrow,
.section-eyebrow {
  margin: 0;
  color: var(--accent);
  text-transform: uppercase;
  letter-spacing: 0.14em;
  font-size: 0.76rem;
  font-weight: 800;
}

.section-eyebrow--study {
  text-transform: none;
  letter-spacing: 0.08em;
  font-size: 0.96rem;
  font-weight: 900;
}

.sidebar-brand h1 {
  margin: 4px 0 0;
  line-height: 1.12;
  font-size: clamp(1.32rem, 2.1vw, 1.85rem);
}

.sidebar-lead {
  margin: 0 0 14px;
  color: var(--muted);
  line-height: 1.7;
  font-size: 0.92rem;
}

.view-tabs {
  display: grid;
  gap: 10px;
  margin-bottom: 14px;
}

.sidebar-stats {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 10px;
  margin-bottom: 14px;
}

.stat-chip,
.summary-mini,
.mini-card,
.toolbar-card,
.filter-panel,
.question-card,
.session-card {
  background: rgba(255, 255, 255, 0.86);
  border: 1px solid rgba(56, 68, 58, 0.10);
}

.stat-chip {
  padding: 11px 12px;
  border-radius: 16px;
}

.stat-label,
.mini-label {
  display: block;
  color: var(--muted);
  font-size: 0.8rem;
}

.stat-chip strong {
  display: block;
  margin-top: 6px;
  font-size: 1.14rem;
}

.sidebar-links {
  display: grid;
  gap: 8px;
  margin-top: 4px;
}

.sidebar-links a,
.footer-note a {
  color: var(--muted);
  text-decoration: none;
  font-size: 0.9rem;
}

.sidebar-links a:hover,
.footer-note a:hover {
  color: var(--accent);
}

.sidebar-footnote {
  margin: 12px 0 0;
  color: var(--muted-2);
  font-size: 0.85rem;
  line-height: 1.6;
}

.app-main {
  display: grid;
  gap: 16px;
}

.view-panel {
  display: none;
  padding: 18px;
}

.view-panel.is-active {
  display: block;
}

.panel-head {
  display: flex;
  justify-content: space-between;
  gap: 14px;
  align-items: end;
  margin-bottom: 16px;
}

.panel-head--register {
  align-items: flex-start;
}

.panel-head__copy {
  display: grid;
  gap: 8px;
  min-width: 0;
}

.panel-head__actions {
  flex: none;
  display: flex;
  align-items: flex-start;
  justify-content: flex-end;
}

.panel-head__actions .secondary-button {
  min-height: 40px;
  padding-inline: 12px;
  white-space: nowrap;
}

.panel-head h1,
.panel-head h2 {
  margin: 0;
  line-height: 1.16;
  font-size: clamp(1.32rem, 1.8vw, 1.7rem);
}

.panel-head h2 {
  margin: 0;
  line-height: 1.14;
}

.panel-note {
  margin: 0;
  color: var(--muted);
  line-height: 1.7;
  max-width: 54ch;
}

.library-toolbar {
  display: grid;
  gap: 14px;
  margin-bottom: 14px;
}

.toolbar-card,
.filter-panel {
  border-radius: 22px;
  box-shadow: 0 14px 26px rgba(93, 74, 38, 0.06);
}

.toolbar-card {
  padding: 15px;
}

.toolbar-card--data {
  background: linear-gradient(180deg, rgba(239, 142, 58, 0.08), rgba(147, 201, 122, 0.08));
}

.toolbar-head h3,
.session-card h3,
.session-card h4 {
  margin: 0;
}

.toolbar-head p {
  margin: 6px 0 0;
  color: var(--muted);
  line-height: 1.6;
}

.filter-panel {
  padding: 16px;
}

.summary-inline {
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: 12px;
  margin-bottom: 14px;
}

.summary-mini {
  padding: 11px 13px;
  border-radius: 18px;
}

.summary-mini strong {
  display: block;
  margin-top: 6px;
  font-size: 1.02rem;
}

.mobile-accordion {
  display: block;
  margin-top: 12px;
}

.mobile-accordion > summary {
  display: none;
  list-style: none;
}

.mobile-accordion > summary::-webkit-details-marker {
  display: none;
}

.mobile-accordion > :not(summary) {
  display: block;
}

.mobile-accordion__label {
  flex: 1 1 auto;
}

.mobile-accordion-toggle {
  display: none;
  flex: 0 0 auto;
  align-items: center;
  justify-content: center;
  width: 1.9rem;
  height: 1.9rem;
  border: 1px solid rgba(118, 93, 52, 0.16);
  border-radius: 999px;
  background: rgba(255, 255, 255, 0.88);
  color: var(--accent);
  font-size: 1rem;
  font-weight: 800;
  line-height: 1;
  cursor: pointer;
}

.mobile-accordion-toggle:hover {
  border-color: rgba(118, 93, 52, 0.24);
}

.mobile-accordion-toggle:focus-visible {
  outline: 2px solid rgba(247, 154, 63, 0.25);
  outline-offset: 2px;
}

.mobile-accordion__body {
  padding-top: 12px;
}

.mobile-accordion__body .helper-row--wide {
  margin-top: 10px;
}

.mobile-accordion__body .form-actions {
  margin-top: 10px;
}

.form-mode {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  padding: 7px 12px;
  border-radius: 999px;
  color: #5e4a23;
  background: rgba(239, 142, 58, 0.14);
  border: 1px solid rgba(239, 142, 58, 0.18);
  font-size: 0.86rem;
  font-weight: 700;
  margin-bottom: 14px;
}

.register-tools {
  display: none;
}

.register-hand-switch {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 8px 10px;
  padding: 10px 12px;
  border-radius: 18px;
  background: rgba(255, 255, 255, 0.72);
  border: 1px solid rgba(56, 68, 58, 0.10);
}

.register-hand-switch__label {
  color: var(--muted);
  font-size: 0.82rem;
  font-weight: 700;
}

.register-hand-switch__buttons {
  display: inline-flex;
  flex-wrap: wrap;
  gap: 8px;
}

.hand-mode-button {
  min-height: 36px;
  padding: 7px 12px;
  border-radius: 999px;
  border: 1px solid rgba(56, 68, 58, 0.12);
  background: rgba(255, 255, 255, 0.92);
  color: var(--text);
  font: inherit;
  font-size: 0.82rem;
  font-weight: 700;
  cursor: pointer;
}

.hand-mode-button.is-current {
  background: linear-gradient(135deg, rgba(239, 142, 58, 0.18), rgba(147, 201, 122, 0.18));
  border-color: rgba(239, 142, 58, 0.26);
  box-shadow: 0 10px 18px rgba(93, 74, 38, 0.08);
}

.register-last-word {
  display: none;
  margin: 0;
  color: var(--muted);
  font-size: 0.8rem;
  line-height: 1.45;
}

.register-last-word strong {
  color: var(--text);
}

.form-grid,
.filter-grid {
  display: grid;
  gap: 12px;
}

.form-grid {
  grid-template-columns: minmax(0, 1.15fr) 260px;
}

.form-grid--main {
  align-items: start;
}

.form-grid--main .field--note {
  grid-column: 1 / -1;
}

.filter-grid {
  grid-template-columns: repeat(3, minmax(0, 1fr));
}

.study-filter-grid {
  grid-template-columns: repeat(4, minmax(0, 1fr));
}

.field {
  display: grid;
  gap: 8px;
}

.field-actions {
  display: flex;
  flex-wrap: wrap;
  gap: 6px;
  margin-top: 2px;
}

.field-actions--term {
  justify-content: flex-start;
}

.field-actions--meaning {
  justify-content: flex-start;
  gap: 8px 12px;
}

.helper-action {
  display: inline-flex;
  align-items: center;
  flex-wrap: wrap;
  gap: 6px 8px;
}

.helper-note {
  color: var(--muted);
  font-size: 0.78rem;
  line-height: 1.35;
  white-space: nowrap;
}

.save-feedback {
  margin: 8px 0 0;
  padding: 8px 10px;
  border-radius: 14px;
  border: 1px solid rgba(147, 201, 122, 0.22);
  background: rgba(147, 201, 122, 0.12);
  color: #355b2b;
  font-size: 0.86rem;
  font-weight: 700;
  line-height: 1.45;
}

.save-feedback[hidden] {
  display: none;
}

.field--full {
  grid-column: 1 / -1;
}

.field--note textarea {
  min-height: 58px;
}

.field-label {
  display: flex;
  justify-content: space-between;
  gap: 12px;
  color: var(--text);
  font-weight: 700;
  font-size: 0.95rem;
}

.field-label em {
  color: var(--muted);
  font-style: normal;
  font-weight: 500;
  font-size: 0.84rem;
}

input,
textarea,
select {
  width: 100%;
  border-radius: 16px;
  border: 1px solid rgba(56, 68, 58, 0.14);
  background: rgba(255, 255, 255, 0.94);
  color: var(--text);
  padding: 10px 12px;
  font: inherit;
  box-shadow: inset 0 1px 0 rgba(255, 255, 255, 0.45);
}

input,
select {
  min-height: 46px;
}

textarea {
  resize: vertical;
  min-height: 64px;
  line-height: 1.48;
}

@media (min-width: 761px) {
  .form-grid--main #meaning-input,
  .form-grid--main #note-input {
    min-height: 46px;
    height: 46px;
  }
}

input::placeholder,
textarea::placeholder {
  color: rgba(95, 111, 100, 0.72);
}

input:focus,
textarea:focus,
select:focus,
button:focus-visible {
  outline: 2px solid rgba(239, 142, 58, 0.40);
  outline-offset: 2px;
}

.field-count {
  color: var(--muted-2);
  font-size: 0.8rem;
}

.helper-row,
.form-actions,
.mode-row,
.study-actions,
.eval-row,
.level-row {
  display: flex;
  flex-wrap: wrap;
  gap: 10px;
}

.helper-row {
  margin-top: 14px;
}

.helper-row--wide {
  margin-top: 12px;
}

.helper-row--register {
  margin-top: 12px;
}

.helper-button,
.primary-button,
.secondary-button,
.danger-button,
.choice-btn,
.eval-button,
.level-pill,
.tab-button {
  font: inherit;
  cursor: pointer;
  transition: transform 0.15s ease, background 0.15s ease, opacity 0.15s ease, box-shadow 0.15s ease;
}

.helper-button,
.secondary-button,
.level-pill,
.tab-button,
.mode-button,
.eval-button {
  min-height: 44px;
}

.helper-button--compact {
  min-height: 36px;
  padding: 7px 10px;
  font-size: 0.78rem;
  width: auto;
}

.tab-button {
  width: 100%;
  display: flex;
  justify-content: flex-start;
  align-items: center;
  gap: 10px;
  padding: 13px 15px;
  border-radius: 18px;
  color: var(--text);
  background: rgba(255, 255, 255, 0.8);
  border: 1px solid rgba(56, 68, 58, 0.10);
  border-left: 4px solid transparent;
  text-decoration: none;
  font-weight: 700;
}

.tab-button.is-active {
  background: linear-gradient(135deg, rgba(239, 142, 58, 0.18), rgba(147, 201, 122, 0.18));
  border-color: rgba(239, 142, 58, 0.24);
  border-left-color: var(--accent);
  box-shadow: 0 10px 18px rgba(93, 74, 38, 0.08);
}

.helper-button,
.secondary-button,
.choice-btn,
.level-pill {
  background: rgba(255, 255, 255, 0.9);
  border: 1px solid rgba(56, 68, 58, 0.12);
  color: var(--text);
}

.primary-button {
  background: linear-gradient(135deg, var(--accent), #f2a454);
  color: #2c1c07;
  font-weight: 800;
  border: 1px solid transparent;
}

.danger-button {
  background: linear-gradient(135deg, #ea8a7f, #d95f53);
  color: #24110f;
  font-weight: 800;
  border: 1px solid transparent;
}

.helper-button:hover,
.tab-button:hover,
.mode-button:hover,
.secondary-button:hover,
.choice-btn:hover,
.eval-button:hover,
.level-pill:hover {
  transform: translateY(-1px);
}

.helper-row--wide {
  margin-top: 12px;
}

.notice,
.save-note {
  margin: 14px 0 0;
  color: var(--muted);
  line-height: 1.75;
}

.save-note {
  font-size: 0.94rem;
}

.library-list {
  display: grid;
  gap: 14px;
}

.top-grid {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 14px;
}

.top-card {
  padding: 18px;
  border-radius: 22px;
  background: rgba(255, 255, 255, 0.9);
  border: 1px solid rgba(56, 68, 58, 0.10);
  box-shadow: 0 16px 28px rgba(93, 74, 38, 0.08);
}

.top-card--lead {
  grid-column: 1 / -1;
  background: linear-gradient(135deg, rgba(255, 244, 225, 0.96), rgba(243, 250, 236, 0.96));
}

.top-card h3 {
  margin: 0 0 10px;
  font-size: 1.02rem;
}

.top-card p {
  margin: 0;
  line-height: 1.78;
  color: var(--muted);
}

.footer-save-link {
  display: none;
  margin: 10px 0 0;
}

.footer-save-link a {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  padding: 9px 14px;
  border-radius: 999px;
  background: rgba(255, 255, 255, 0.84);
  border: 1px solid rgba(56, 68, 58, 0.10);
  color: var(--accent);
  text-decoration: none;
  font-weight: 800;
}

.empty-state {
  padding: 22px;
  border-radius: 20px;
  border: 1px dashed rgba(56, 68, 58, 0.20);
  color: var(--muted);
  line-height: 1.8;
  background: rgba(255, 255, 255, 0.60);
}

.word-grid {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 14px;
}

.library-mobile-shell {
  display: grid;
  gap: 12px;
}

.library-mobile-header {
  display: flex;
  flex-wrap: wrap;
  gap: 10px;
  justify-content: space-between;
  align-items: center;
}

.library-mobile-position {
  display: inline-flex;
  align-items: center;
  padding: 7px 11px;
  border-radius: 999px;
  background: rgba(255, 255, 255, 0.86);
  border: 1px solid rgba(56, 68, 58, 0.10);
  color: var(--muted);
  font-size: 0.84rem;
  font-weight: 800;
}

.library-mobile-nav {
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
  margin-left: auto;
}

.library-mobile-card {
  width: 100%;
}

.library-mobile-stage {
  position: relative;
}

.library-mobile-stage.is-animating {
  overflow: hidden;
  perspective: 1200px;
}

.library-mobile-stage.is-animating .library-mobile-card {
  position: absolute;
  inset: 0;
  width: 100%;
  margin: 0;
  will-change: transform, opacity;
  transform-style: preserve-3d;
  backface-visibility: hidden;
}

.library-mobile-stage.is-animating .library-mobile-card--sizer {
  position: relative;
  inset: auto;
  visibility: hidden;
  pointer-events: none;
}

.library-mobile-stage.is-animating .library-mobile-card--outgoing {
  z-index: 2;
}

.library-mobile-stage.is-animating .library-mobile-card--incoming {
  z-index: 1;
}

.library-mobile-stage.is-motion-next .library-mobile-card--outgoing {
  animation: library-card-out-left 280ms cubic-bezier(0.22, 0.61, 0.36, 1) forwards;
}

.library-mobile-stage.is-motion-next .library-mobile-card--incoming {
  animation: library-card-in-right 280ms cubic-bezier(0.22, 0.61, 0.36, 1) forwards;
}

.library-mobile-stage.is-motion-prev .library-mobile-card--outgoing {
  animation: library-card-out-right 280ms cubic-bezier(0.22, 0.61, 0.36, 1) forwards;
}

.library-mobile-stage.is-motion-prev .library-mobile-card--incoming {
  animation: library-card-in-left 280ms cubic-bezier(0.22, 0.61, 0.36, 1) forwards;
}

.word-meaning--mobile {
  margin-top: 6px;
  color: var(--muted);
  font-size: 0.94rem;
  line-height: 1.65;
}

.word-card {
  padding: 17px;
  border-radius: 22px;
  background: rgba(255, 255, 255, 0.90);
  border: 1px solid rgba(56, 68, 58, 0.10);
  box-shadow: 0 16px 28px rgba(93, 74, 38, 0.08);
}

.word-card__top {
  display: flex;
  justify-content: space-between;
  gap: 10px;
  align-items: start;
  margin-bottom: 12px;
}

.word-term {
  margin: 0;
  font-size: 1.15rem;
  line-height: 1.4;
  word-break: break-word;
}

.word-meta {
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
  margin-top: 10px;
}

.chip {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  padding: 5px 9px;
  border-radius: 999px;
  background: rgba(255, 255, 255, 0.9);
  border: 1px solid rgba(56, 68, 58, 0.10);
  color: var(--text);
  font-size: 0.78rem;
}

.chip.level-a {
  border-color: rgba(95, 174, 99, 0.30);
  color: #477e4b;
}

.chip.level-b {
  border-color: rgba(211, 168, 79, 0.30);
  color: #8d6c26;
}

.chip.level-c {
  border-color: rgba(220, 111, 99, 0.30);
  color: #a24c43;
}

.word-meaning,
.word-note {
  margin: 10px 0 0;
  line-height: 1.75;
  word-break: break-word;
}

.word-meaning { color: var(--muted); }
.word-note { color: #536558; }

.word-actions {
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
  margin-top: 14px;
}

.word-actions button { padding: 9px 11px; font-size: 0.9rem; }

.word-stats {
  margin-top: 12px;
  color: var(--muted);
  font-size: 0.84rem;
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
}

.mode-row { margin-bottom: 14px; }

.mode-button {
  padding: 10px 14px;
  border-radius: 999px;
  background: rgba(255, 255, 255, 0.88);
  color: var(--text);
  border: 1px solid rgba(56, 68, 58, 0.12);
  font-weight: 700;
}

.mode-button.is-active {
  background: linear-gradient(135deg, rgba(239, 142, 58, 0.16), rgba(147, 201, 122, 0.16));
  border-color: rgba(239, 142, 58, 0.24);
  box-shadow: 0 10px 18px rgba(93, 74, 38, 0.08);
}

.study-shell { display: grid; gap: 14px; }

.study-shell.is-study-complete .study-status,
.study-shell.is-study-complete .study-grid {
  display: none;
}

.study-status {
  display: flex;
  flex-wrap: wrap;
  gap: 10px;
  justify-content: space-between;
  align-items: center;
  color: var(--muted);
  padding: 0 4px;
}

.study-status .secondary-button {
  margin-left: auto;
}

.study-complete-card {
  padding: 18px;
  border-radius: 22px;
  box-shadow: 0 14px 26px rgba(93, 74, 38, 0.06);
  background: linear-gradient(180deg, rgba(255, 255, 255, 0.92), rgba(248, 240, 220, 0.92));
  border: 1px solid rgba(56, 68, 58, 0.10);
  margin-bottom: 14px;
}

.study-complete-card__eyebrow,
.study-complete-card__lead {
  margin: 0;
}

.study-complete-card__eyebrow {
  color: var(--accent);
  font-size: 0.82rem;
  text-transform: uppercase;
  letter-spacing: 0.12em;
  font-weight: 800;
}

.study-complete-card h3 {
  margin: 8px 0 6px;
  font-size: clamp(1.4rem, 3vw, 1.8rem);
}

.study-complete-card__lead {
  color: var(--muted);
  line-height: 1.75;
}

.study-complete-stats {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 12px;
  margin-top: 14px;
}

.study-complete-stats article {
  padding: 14px;
  border-radius: 18px;
  background: rgba(255, 255, 255, 0.78);
  border: 1px solid rgba(56, 68, 58, 0.10);
}

.study-complete-stats span {
  display: block;
  color: var(--muted);
  font-size: 0.84rem;
  margin-bottom: 8px;
}

.study-complete-stats strong {
  display: flex;
  align-items: baseline;
  gap: 4px;
  font-size: 1.4rem;
}

.study-complete-actions {
  margin-top: 16px;
}

.study-grid {
  display: grid;
  grid-template-columns: minmax(0, 1.32fr) minmax(240px, 0.68fr);
  gap: 14px;
}

.question-card,
.session-card {
  padding: 17px;
  border-radius: 22px;
  box-shadow: 0 14px 26px rgba(93, 74, 38, 0.06);
}

.question-head {
  display: flex;
  justify-content: space-between;
  gap: 14px;
  align-items: flex-start;
  margin-bottom: 14px;
}

.study-speak-button {
  width: auto;
  min-width: 0;
  align-self: flex-start;
}

.question-head h3 {
  margin: 0;
}

.study-start-rail {
  display: flex;
  justify-content: flex-start;
  margin: 2px 0 12px;
}

.study-start-button {
  min-height: 48px;
  padding: 11px 18px;
  width: auto;
  min-width: 180px;
}

.question-text {
  margin: 0;
  font-size: clamp(1.45rem, 2.8vw, 2rem);
  line-height: 1.42;
  word-break: break-word;
}

.answer-card {
  margin-top: 16px;
  padding: 16px;
  border-radius: 18px;
  background: rgba(255, 255, 255, 0.78);
  border: 1px solid rgba(56, 68, 58, 0.10);
}

.answer-label {
  margin: 0 0 8px;
  color: var(--accent);
  font-size: 0.82rem;
  text-transform: uppercase;
  letter-spacing: 0.12em;
  font-weight: 800;
}

.answer-main { font-size: 1.28rem; line-height: 1.6; }

.answer-sub,
.answer-note {
  margin-top: 8px;
  color: var(--muted);
  line-height: 1.75;
  word-break: break-word;
}

.choice-grid {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 12px;
  margin-top: 16px;
}

.choice-btn {
  min-height: 64px;
  text-align: left;
  line-height: 1.5;
  padding: 14px;
  word-break: break-word;
}

.choice-btn.is-correct {
  background: rgba(95, 174, 99, 0.16);
  border-color: rgba(95, 174, 99, 0.30);
}

.choice-btn.is-wrong {
  background: rgba(220, 111, 99, 0.16);
  border-color: rgba(220, 111, 99, 0.30);
}

.study-actions { margin-top: 16px; }

.eval-row,
.level-row { margin-top: 14px; }

.eval-button.good {
  background: rgba(95, 174, 99, 0.16);
  border: 1px solid rgba(95, 174, 99, 0.26);
}

.eval-button.close {
  background: rgba(211, 168, 79, 0.16);
  border: 1px solid rgba(211, 168, 79, 0.26);
}

.eval-button.bad {
  background: rgba(220, 111, 99, 0.16);
  border: 1px solid rgba(220, 111, 99, 0.26);
}

.level-row { align-items: center; }

.level-row__label {
  color: var(--muted);
  margin-right: 4px;
}

.level-pill.is-current {
  border-color: rgba(239, 142, 58, 0.40);
  box-shadow: 0 0 0 2px rgba(239, 142, 58, 0.12), 0 10px 18px rgba(93, 74, 38, 0.08);
  font-weight: 800;
}

.level-pill[data-level="A"].is-current {
  background: rgba(95, 174, 99, 0.18);
}

.level-pill[data-level="B"].is-current {
  background: rgba(211, 168, 79, 0.18);
}

.level-pill[data-level="C"].is-current {
  background: rgba(220, 111, 99, 0.18);
}

.session-stats {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 12px;
}

.session-stats article {
  padding: 14px;
  border-radius: 16px;
  background: rgba(255, 255, 255, 0.82);
  border: 1px solid rgba(56, 68, 58, 0.08);
}

.session-stats article span {
  display: block;
  color: var(--muted);
  font-size: 0.82rem;
}

.session-stats article strong {
  display: block;
  margin-top: 8px;
  font-size: 1.28rem;
}

.session-history { margin-top: 16px; }

.session-history ul {
  margin: 10px 0 0;
  padding-left: 18px;
  color: var(--muted);
  line-height: 1.8;
  max-height: 8.8em;
  overflow: auto;
  padding-right: 4px;
}

.study-toast {
  position: fixed;
  left: 50%;
  bottom: calc(18px + env(safe-area-inset-bottom) + 58px);
  transform: translateX(-50%) translateY(10px);
  opacity: 0;
  pointer-events: none;
  z-index: 60;
  max-width: min(92vw, 420px);
  padding: 11px 14px;
  border-radius: 999px;
  background: rgba(43, 35, 24, 0.92);
  color: #fff;
  box-shadow: 0 16px 28px rgba(31, 23, 12, 0.24);
  font-size: 0.9rem;
  line-height: 1.45;
  text-align: center;
  transition: opacity 0.18s ease, transform 0.18s ease;
}

.study-toast.is-visible {
  opacity: 1;
  transform: translateX(-50%) translateY(0);
}

.app-footer {
  margin-top: 16px;
  padding: 14px 18px;
  color: var(--muted);
  text-align: center;
  width: min(100%, 920px);
  margin-left: auto;
  margin-right: auto;
}

.mobile-tabbar {
  display: none;
}

.footer-note { margin: 8px 0 0; }

button[hidden] { display: none !important; }

@media (max-width: 767px) {
  .app-layout {
    grid-template-columns: 1fr;
  }

  .app-sidebar {
    position: static;
  }

  .sidebar-stats {
    grid-template-columns: repeat(4, minmax(0, 1fr));
  }

  .summary-inline {
    grid-template-columns: repeat(3, minmax(0, 1fr));
  }

  .form-grid {
    grid-template-columns: minmax(0, 1fr) 240px;
  }

  .filter-grid {
    grid-template-columns: repeat(2, minmax(0, 1fr));
  }

  .study-filter-grid {
    grid-template-columns: repeat(4, minmax(0, 1fr));
  }

  .study-grid,
  .word-grid {
    grid-template-columns: 1fr;
  }
}

@media (max-width: 760px) {
  .app-shell {
    width: min(100% - 12px, 1280px);
    padding-top: 10px;
    padding-bottom: calc(260px + env(safe-area-inset-bottom));
  }

  body.is-register-view .app-shell {
    padding-bottom: calc(112px + env(safe-area-inset-bottom));
  }

  .app-sidebar,
  .view-panel,
  .app-footer,
  .toolbar-card,
  .filter-panel,
  .question-card,
  .session-card {
    border-radius: 20px;
  }

  .app-sidebar,
  .view-panel {
    padding: 11px;
  }

  .sidebar-brand {
    align-items: flex-start;
    margin-bottom: 4px;
    gap: 8px;
  }

  .eyebrow {
    display: none;
  }

  .sidebar-logo {
    width: 36px;
    height: 36px;
    border-radius: 11px;
  }

  .sidebar-brand h1 {
    margin-top: 2px;
    font-size: 1.04rem;
  }

  .sidebar-lead {
    margin-bottom: 5px;
    line-height: 1.22;
    font-size: 0.7rem;
    display: -webkit-box;
    -webkit-line-clamp: 1;
    -webkit-box-orient: vertical;
    overflow: hidden;
  }

  .view-tabs {
    display: none;
  }

  .tab-button {
    justify-content: center;
    padding: 10px 8px;
    font-size: 0.9rem;
  }

  .sidebar-stats,
  .summary-inline {
    grid-template-columns: repeat(4, minmax(0, 1fr));
  }

  .sidebar-stats {
    gap: 4px;
    margin-bottom: 8px;
  }

  .stat-chip {
    padding: 6px 6px;
    border-radius: 12px;
  }

  .stat-label {
    font-size: 0.56rem;
    line-height: 1.1;
  }

  .stat-chip strong {
    margin-top: 2px;
    font-size: 0.78rem;
  }

  .summary-inline {
    grid-template-columns: repeat(3, minmax(0, 1fr));
    gap: 6px;
  }

  .sidebar-links {
    grid-template-columns: 1fr;
    gap: 6px;
  }

  .sidebar-links a {
    font-size: 0.82rem;
  }

  .sidebar-links a[href="./about.html"] {
    display: none;
  }

  .sidebar-footnote {
    display: none;
  }

  body.is-mobile-study-view .sidebar-lead,
  body.is-mobile-study-view .sidebar-stats,
  body.is-mobile-study-view .sidebar-links,
  body.is-mobile-study-view .sidebar-footnote {
    display: none;
  }

  .summary-inline {
    gap: 10px;
  }

  .form-grid,
  .filter-grid,
  .choice-grid {
    grid-template-columns: 1fr;
  }

  .form-grid--main {
    grid-template-columns: repeat(2, minmax(0, 1fr));
  }

  .form-grid--main .field--note {
    grid-column: 1 / -1;
  }

  .form-grid--secondary {
    grid-template-columns: repeat(2, minmax(0, 1fr));
  }

  .form-grid {
    gap: 10px;
  }

  .filter-grid {
    gap: 10px;
  }

  .study-filter-grid {
    grid-template-columns: repeat(2, minmax(0, 1fr));
  }

  .panel-head,
  .question-head,
  .study-status {
    flex-direction: column;
    align-items: flex-start;
  }

  .panel-head--top {
    margin-bottom: 12px;
  }

  .view-panel[data-view-panel="study"].is-mobile-study-active .question-head {
    flex-direction: row;
    align-items: flex-start;
  }

  .view-panel[data-view-panel="study"].is-mobile-study-active .question-head h3 {
    font-size: 1.18rem;
  }

  .view-panel[data-view-panel="study"].is-mobile-study-active .toolbar-card {
    display: none;
  }

  .view-panel[data-view-panel="study"].is-mobile-study-active .session-card {
    display: none;
  }

  .view-panel[data-view-panel="study"].is-mobile-study-setup .study-shell {
    display: none;
  }

  .panel-head {
    margin-bottom: 12px;
  }

  .panel-head--register {
    display: grid;
    grid-template-columns: minmax(0, 1fr) auto;
    gap: 4px 8px;
    align-items: start;
  }

  .panel-head--study {
    margin-bottom: 8px;
  }

  .panel-head__copy {
    gap: 4px;
  }

  .panel-head__copy--study {
    gap: 0;
  }

  .view-panel[data-view-panel="register"] .panel-head__copy {
    grid-column: 1;
    grid-row: 1;
    min-width: 0;
  }

  .view-panel[data-view-panel="register"] .register-last-word {
    display: block;
    grid-column: 1 / -1;
    grid-row: 2;
    width: 100%;
    max-width: 100%;
    min-width: 0;
    margin: 0;
    padding: 5px 8px;
    border-radius: 12px;
    background: rgba(255, 255, 255, 0.74);
    border: 1px solid rgba(56, 68, 58, 0.10);
    color: var(--muted);
    font-size: 0.68rem;
    line-height: 1.25;
    white-space: nowrap;
    overflow: hidden;
    text-overflow: ellipsis;
  }

  .view-panel[data-view-panel="register"] .register-last-word strong {
    color: var(--text);
  }

  .view-panel[data-view-panel="register"] .panel-head__actions {
    grid-column: 2;
    grid-row: 1;
    justify-self: end;
    align-self: start;
  }

  .panel-head__actions .secondary-button {
    min-height: 30px;
    padding: 4px 8px;
    font-size: 0.66rem;
  }

  .view-panel[data-view-panel="register"] .panel-head__actions .secondary-button {
    width: auto;
    white-space: nowrap;
  }

  .panel-head h1,
  .panel-head h2 {
    font-size: 1.02rem;
  }

  .panel-note {
    font-size: 0.74rem;
    line-height: 1.32;
    display: -webkit-box;
    -webkit-line-clamp: 2;
    -webkit-box-orient: vertical;
    overflow: hidden;
  }

  .view-panel[data-view-panel="register"] .panel-note {
    display: none;
  }

  .view-panel[data-view-panel="register"] .panel-head h2 {
    display: none;
  }

  .save-note {
    display: none !important;
  }

  .form-mode {
    display: none;
  }

  .register-tools {
    display: grid;
    gap: 4px;
    margin: 8px 0 10px;
  }

  .register-hand-switch {
    display: grid;
    grid-template-columns: auto minmax(0, 1fr);
    align-items: center;
    gap: 6px 8px;
    padding: 7px 9px;
    border-radius: 12px;
  }

  .register-hand-switch__label {
    font-size: 0.66rem;
  }

  .register-hand-switch__buttons {
    display: grid;
    grid-template-columns: repeat(2, minmax(0, 1fr));
    gap: 6px;
  }

  .hand-mode-button {
    min-height: 30px;
    padding: 5px 8px;
    font-size: 0.68rem;
    width: 100%;
    box-sizing: border-box;
  }

  .register-last-word {
    font-size: 0.7rem;
  }

  .toolbar-card,
  .filter-panel,
  .question-card,
  .session-card {
    padding: 10px;
  }

  .form-mode {
    margin-bottom: 8px;
    padding: 5px 10px;
    font-size: 0.72rem;
  }

  .field {
    gap: 5px;
  }

  .field-actions {
    gap: 5px;
  }

  .field-actions--term {
    justify-content: flex-start;
  }

  .field-actions--term .helper-button {
    width: auto;
    min-width: 0;
  }

  .field-actions--meaning {
    display: grid;
    grid-template-columns: repeat(2, minmax(0, 1fr));
    width: 100%;
    gap: 6px;
  }

  .field-actions--meaning .helper-button {
    width: 100%;
    min-width: 0;
    padding-inline: 8px;
    white-space: nowrap;
  }

  .field-label {
    font-size: 0.78rem;
  }

  .form-grid--main {
    grid-template-columns: minmax(0, 1.35fr) minmax(112px, 0.85fr);
    grid-template-areas:
      "term term-language"
      "meaning meaning-language"
      "category level"
      "note note";
    align-items: start;
  }

  body.is-register-hand-right .view-panel[data-view-panel="register"] .form-grid--main {
    grid-template-columns: minmax(112px, 0.85fr) minmax(0, 1.35fr);
    grid-template-areas:
      "term-language term"
      "meaning-language meaning"
      "category level"
      "note note";
  }

  .view-panel[data-view-panel="register"] .field--term {
    grid-area: term;
  }

  .view-panel[data-view-panel="register"] .field--term-language {
    grid-area: term-language;
  }

  .view-panel[data-view-panel="register"] .field--meaning {
    grid-area: meaning;
  }

  .view-panel[data-view-panel="register"] .field--meaning-language {
    grid-area: meaning-language;
  }

  .view-panel[data-view-panel="register"] .field--category {
    grid-area: category;
  }

  .view-panel[data-view-panel="register"] .field--level {
    grid-area: level;
  }

  .view-panel[data-view-panel="register"] .field--note-area {
    grid-area: note;
  }

  .form-grid--main .field {
    gap: 4px;
  }

  .form-grid--main .field-label {
    flex-direction: row;
    align-items: center;
    justify-content: space-between;
    min-height: 2.35em;
    font-size: 0.72rem;
    line-height: 1.18;
  }

  .form-grid--main .field-label em {
    font-size: 0.66rem;
  }

  .save-feedback {
    margin-top: 6px;
    padding: 7px 9px;
    font-size: 0.76rem;
  }

  .view-panel[data-view-panel="register"] .save-feedback {
    position: fixed;
    left: 50%;
    top: 50%;
    z-index: 99999;
    width: min(calc(100vw - 24px), 380px);
    margin: 0;
    padding: 16px 22px;
    border-radius: 999px;
    text-align: center;
    pointer-events: none;
    transform: translate(-50%, -50%);
    background: rgba(34, 49, 38, 0.94);
    border: 1px solid rgba(255, 255, 255, 0.18);
    color: #fff;
    font-size: 1rem;
    font-weight: 800;
    line-height: 1.3;
    box-shadow: 0 22px 52px rgba(0, 0, 0, 0.28);
    backdrop-filter: blur(10px);
    white-space: nowrap;
    overflow: hidden;
    text-overflow: ellipsis;
  }

  input,
  textarea,
  select {
    border-radius: 14px;
  }

  input,
  select {
    min-height: 34px;
    padding: 6px 8px;
    font-size: 0.8rem;
  }

  textarea {
    min-height: 40px;
    padding: 6px 8px;
    font-size: 0.8rem;
  }

  .form-grid--main #meaning-input,
  .form-grid--main #note-input {
    min-height: 34px;
    height: 34px;
    padding-block: 6px;
    line-height: 1.3;
  }

  .helper-row--wide {
    margin-top: 8px;
    gap: 5px;
  }

  .helper-row--register {
    display: grid;
    grid-template-columns: repeat(3, minmax(0, 1fr));
    gap: 5px;
    margin-top: 8px;
  }

  .helper-button,
  .primary-button,
  .secondary-button,
  .danger-button {
    min-height: 34px;
    padding: 6px 8px;
    font-size: 0.74rem;
  }

  .helper-button--compact {
    min-height: 32px;
    padding: 5px 8px;
    font-size: 0.72rem;
  }

  .field-label {
    flex-direction: column;
    align-items: flex-start;
  }

  .helper-row,
  .form-actions,
  .mode-row,
  .study-actions,
  .eval-row {
    flex-direction: column;
  }

  .level-row {
    display: grid;
    grid-template-columns: repeat(3, minmax(0, 1fr));
    gap: 7px;
    align-items: stretch;
  }

  .level-row__label {
    grid-column: 1 / -1;
  }

  .helper-button,
  .primary-button,
  .secondary-button,
  .danger-button,
  .mode-button,
  .choice-btn,
  .eval-button,
  .level-pill {
    width: 100%;
    justify-content: center;
  }

  .mode-row {
    display: grid;
    grid-template-columns: repeat(3, minmax(0, 1fr));
    gap: 6px;
  }

  .mode-button {
    width: 100%;
    flex: none;
    font-size: 0.72rem;
    padding: 7px 6px;
  }

  .helper-button {
    width: 100%;
  }

  .top-grid {
    grid-template-columns: 1fr;
    gap: 10px;
  }

  .top-card {
    padding: 14px;
    border-radius: 18px;
  }

  .top-card h3 {
    font-size: 0.96rem;
  }

  .top-card p {
    font-size: 0.82rem;
    line-height: 1.72;
  }

  .footer-save-link {
    display: block;
    margin-top: 8px;
  }

  .footer-note {
    display: none !important;
  }

  .study-start-rail {
    margin: 0 0 10px;
  }

  .study-start-button,
  .view-panel[data-view-panel="study"] #study-start-btn {
    width: 100%;
  }

  .word-card__top {
    flex-direction: column;
  }

  .session-stats {
    grid-template-columns: repeat(2, minmax(0, 1fr));
  }

  .session-stats {
    gap: 6px;
  }

  .session-stats article {
    padding: 9px 10px;
  }

  .session-stats article span {
    font-size: 0.72rem;
  }

  .session-stats article strong {
    font-size: 1rem;
  }

  .study-status {
    flex-direction: row;
    gap: 6px;
    font-size: 0.78rem;
  }

  body.is-mobile-study-active .study-status #study-count-label {
    display: none;
  }

  body.is-mobile-study-active .study-status .secondary-button {
    width: auto;
    margin-left: auto;
    flex: 0 0 auto;
  }

  .study-status span {
    white-space: nowrap;
  }

  .choice-grid {
    gap: 8px;
    margin-top: 12px;
  }

  .choice-btn {
    min-height: 52px;
    padding: 10px 11px;
    font-size: 0.82rem;
    line-height: 1.45;
  }

  .study-actions {
    flex-direction: row;
  }

  .study-actions .primary-button,
  .study-actions .secondary-button {
    width: auto;
    flex: 1 1 0;
  }

  .eval-row {
    display: grid;
    grid-template-columns: repeat(3, minmax(0, 1fr));
    gap: 6px;
  }

  .eval-button {
    min-height: 36px;
    padding: 7px 6px;
    font-size: 0.78rem;
  }

  .level-row {
    padding-top: 2px;
  }

  .level-pill {
    min-height: 34px;
    padding: 7px 9px;
    font-size: 0.76rem;
    line-height: 1.22;
    white-space: nowrap;
    min-width: 0;
  }

  .level-pill.is-current {
    box-shadow: 0 0 0 2px rgba(239, 142, 58, 0.14);
  }

  .question-text {
    font-size: 1.24rem;
  }

  .study-speak-button {
    width: auto;
  }

  .library-mobile-shell {
    gap: 10px;
  }

  .library-mobile-header {
    gap: 8px;
  }

  .library-mobile-nav {
    width: 100%;
  }

  .library-mobile-nav .secondary-button {
    width: auto;
    flex: 1 1 0;
  }

  .library-mobile-card .word-card__top {
    margin-bottom: 10px;
  }

  .library-mobile-card .word-meta {
    margin-top: 8px;
  }

  .library-mobile-card .word-actions {
    display: grid;
    grid-template-columns: repeat(2, minmax(0, 1fr));
    gap: 6px;
  }

  .library-mobile-card .word-actions button {
    width: 100%;
    padding: 8px 7px;
    font-size: 0.76rem;
  }

  .session-history ul {
    max-height: 6.6em;
  }

  .study-toast {
    bottom: calc(82px + env(safe-area-inset-bottom));
    width: min(100% - 24px, 420px);
    max-width: none;
    white-space: normal;
  }

  .app-footer {
    width: 100%;
    margin-left: 0;
    margin-right: 0;
    padding-inline: 14px;
    padding-block: 12px;
    font-size: 0.9rem;
  }

  @keyframes library-card-out-left {
    from {
      transform: translateX(0) rotate(0deg) scale(1);
      opacity: 1;
      filter: saturate(1);
    }

    to {
      transform: translateX(-26%) rotate(-8deg) scale(0.97);
      opacity: 0.18;
      filter: saturate(0.92);
    }
  }

  @keyframes library-card-in-right {
    from {
      transform: translateX(18%) rotate(7deg) scale(0.97);
      opacity: 0;
      filter: saturate(0.95);
    }

    to {
      transform: translateX(0) rotate(0deg) scale(1);
      opacity: 1;
      filter: saturate(1);
    }
  }

  @keyframes library-card-out-right {
    from {
      transform: translateX(0) rotate(0deg) scale(1);
      opacity: 1;
      filter: saturate(1);
    }

    to {
      transform: translateX(26%) rotate(8deg) scale(0.97);
      opacity: 0.18;
      filter: saturate(0.92);
    }
  }

  @keyframes library-card-in-left {
    from {
      transform: translateX(-18%) rotate(-7deg) scale(0.97);
      opacity: 0;
      filter: saturate(0.95);
    }

    to {
      transform: translateX(0) rotate(0deg) scale(1);
      opacity: 1;
      filter: saturate(1);
    }
  }

  .mobile-tabbar {
    position: fixed;
    left: 50%;
    bottom: calc(12px + env(safe-area-inset-bottom));
    transform: translateX(-50%);
    width: min(100% - 12px, 560px);
    display: grid;
    grid-template-columns: repeat(4, minmax(0, 1fr));
    gap: 6px;
    padding: 9px;
    border-radius: 24px;
    border: 1px solid rgba(56, 68, 58, 0.14);
    background: rgba(255, 251, 244, 0.98);
    box-shadow: 0 18px 36px rgba(93, 74, 38, 0.18);
    backdrop-filter: blur(14px);
    z-index: 40;
  }

  .mobile-tabbar .mobile-tab-button {
    width: 100%;
    min-height: 48px;
    padding: 10px 6px;
    border-radius: 18px;
    justify-content: center;
    border: 1px solid rgba(56, 68, 58, 0.12);
    background: rgba(255, 255, 255, 0.94);
    font-size: 0.78rem;
    font-weight: 800;
  }

  .mobile-tabbar .mobile-tab-button.is-active {
    background: linear-gradient(135deg, rgba(239, 142, 58, 0.26), rgba(255, 236, 205, 0.98));
    border-color: rgba(239, 142, 58, 0.34);
    color: #2a402d;
    box-shadow: 0 12px 20px rgba(93, 74, 38, 0.12);
  }

  .mobile-accordion {
    margin-top: 10px;
    border: 1px solid rgba(56, 68, 58, 0.10);
    border-radius: 18px;
    background: rgba(255, 255, 255, 0.74);
    box-shadow: 0 12px 24px rgba(93, 74, 38, 0.06);
    overflow: hidden;
  }

  .mobile-accordion > summary {
    display: flex;
    align-items: center;
    justify-content: space-between;
    gap: 10px;
    padding: 10px 12px;
    color: var(--text);
    font-size: 0.82rem;
    font-weight: 800;
    cursor: default;
    background: linear-gradient(135deg, rgba(255, 249, 241, 0.98), rgba(241, 250, 236, 0.98));
  }

  .mobile-accordion-toggle {
    display: inline-flex;
  }

  .mobile-accordion > :not(summary) {
    display: none;
  }

  .mobile-accordion[open] > :not(summary) {
    display: block;
  }

  .mobile-accordion__body {
    padding: 10px 10px 12px;
  }

  .mobile-accordion__body .form-grid {
    gap: 8px;
  }

  .mobile-accordion__body .filter-grid,
  .mobile-accordion__body .study-filter-grid {
    grid-template-columns: repeat(2, minmax(0, 1fr));
    gap: 8px;
  }

  .mobile-accordion__body .summary-inline {
    grid-template-columns: repeat(3, minmax(0, 1fr));
    gap: 6px;
    margin-bottom: 10px;
  }

  .mobile-accordion__body .summary-mini {
    padding: 7px 8px;
    border-radius: 14px;
  }

  .mobile-accordion__body .summary-mini strong {
    margin-top: 3px;
    font-size: 0.78rem;
  }

  .mobile-accordion__body .toolbar-head p {
    font-size: 0.76rem;
    line-height: 1.32;
  }

  .mobile-accordion__body .helper-row {
    margin-top: 10px;
    gap: 6px;
  }

  .mobile-accordion__body .helper-button,
  .mobile-accordion__body .secondary-button,
  .mobile-accordion__body .danger-button {
    min-height: 40px;
    padding: 9px 10px;
  }
}