:root {
  color-scheme: light;
  --bg: #f7fbf7;
  --panel: #ffffff;
  --panel-soft: #eef6f2;
  --ink: #17231d;
  --muted: #68776f;
  --line: #dce8e1;
  --green: #256f5b;
  --green-dark: #184c3e;
  --amber: #d98f2b;
  --red: #c9534b;
  --blue: #3c67a6;
  --violet: #7562a8;
  --shadow: 0 18px 45px rgba(22, 59, 42, 0.12);
  --radius: 8px;
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", "PingFang SC", "Microsoft YaHei", sans-serif;
}

* {
  box-sizing: border-box;
}

body {
  margin: 0;
  min-height: 100vh;
  background: var(--bg);
  color: var(--ink);
}

button,
input,
select,
textarea {
  font: inherit;
}

button {
  border: 0;
}

button:disabled {
  cursor: not-allowed;
  opacity: 0.55;
}

.shell {
  display: grid;
  grid-template-columns: 272px minmax(0, 1fr);
  min-height: 100vh;
}

.sidebar {
  position: sticky;
  top: 0;
  height: 100vh;
  display: flex;
  flex-direction: column;
  gap: 24px;
  padding: 24px;
  border-right: 1px solid var(--line);
  background: rgba(255, 255, 255, 0.72);
  backdrop-filter: blur(18px);
}

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

.brand-mark {
  display: grid;
  width: 48px;
  height: 48px;
  place-items: center;
  border-radius: 8px;
  background: var(--green);
  color: #fff;
  font-weight: 800;
}

.brand strong,
.brand span,
.sync-panel strong,
.sync-panel span {
  display: block;
}

.brand strong {
  font-size: 17px;
}

.brand span,
.sync-panel span,
.eyebrow,
.muted {
  color: var(--muted);
}

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

.nav-item {
  min-height: 48px;
  padding: 0 14px;
  border-radius: var(--radius);
  background: transparent;
  color: var(--muted);
  text-align: left;
  cursor: pointer;
}

.nav-item.active {
  background: var(--green-dark);
  color: #fff;
  font-weight: 700;
}

.sync-panel {
  display: flex;
  align-items: center;
  gap: 10px;
  margin-top: auto;
  padding: 14px;
  border: 1px solid var(--line);
  border-radius: var(--radius);
  background: #fff;
}

.resume-banner {
  display: grid;
  gap: 8px;
  margin-top: 14px;
  padding: 14px;
  border: 1px solid rgba(37, 111, 91, 0.26);
  border-radius: var(--radius);
  background: rgba(255, 255, 255, 0.7);
}

.resume-banner .secondary-button,
.resume-banner .ghost-button {
  width: fit-content;
}

.app-build-badge {
  position: fixed;
  left: 50%;
  bottom: max(10px, env(safe-area-inset-bottom));
  z-index: 50;
  display: inline-flex;
  align-items: center;
  gap: 8px;
  max-width: calc(100vw - 24px);
  padding: 5px 7px 5px 10px;
  border: 1px solid rgba(24, 82, 66, 0.18);
  border-radius: 999px;
  background: rgba(255, 255, 255, 0.88);
  box-shadow: 0 10px 26px rgba(23, 64, 51, 0.12);
  color: var(--muted);
  font-size: 11px;
  line-height: 1.4;
  backdrop-filter: blur(10px);
}

.app-build-badge[hidden] {
  display: none;
}

.app-build-badge span {
  overflow: hidden;
  text-overflow: ellipsis;
  white-space: nowrap;
}

.manual-update-button {
  min-height: 24px;
  padding: 3px 8px;
  border: 0;
  border-radius: 999px;
  background: var(--green);
  color: #fff;
  font-size: 11px;
  font-weight: 700;
  white-space: nowrap;
  cursor: pointer;
}

.manual-update-button:disabled {
  opacity: 0.6;
  cursor: default;
}

.status-dot {
  width: 10px;
  height: 10px;
  border-radius: 99px;
  background: #38a66c;
  box-shadow: 0 0 0 6px rgba(56, 166, 108, 0.12);
}

.main {
  width: min(1180px, 100%);
  margin: 0 auto;
  padding: 28px;
}

.topbar {
  display: flex;
  align-items: flex-start;
  justify-content: space-between;
  gap: 20px;
  margin-bottom: 22px;
}

.eyebrow {
  margin: 0 0 6px;
  font-weight: 700;
}

h1,
h2,
h3,
p {
  margin-top: 0;
}

h1 {
  margin-bottom: 0;
  font-size: 34px;
  line-height: 1.18;
  letter-spacing: 0;
}

h2 {
  margin-bottom: 14px;
  font-size: 24px;
  line-height: 1.25;
  letter-spacing: 0;
}

h3 {
  margin-bottom: 8px;
  font-size: 18px;
}

.top-actions,
.button-row,
.segmented,
.field-row,
.metric-row,
.chip-row {
  display: flex;
  flex-wrap: wrap;
  gap: 10px;
}

.icon-button {
  display: grid;
  min-width: 46px;
  height: 46px;
  place-items: center;
  border: 1px solid var(--line);
  border-radius: var(--radius);
  background: var(--panel);
  color: var(--ink);
  cursor: pointer;
  box-shadow: 0 8px 22px rgba(22, 59, 42, 0.08);
}

.view {
  display: none;
}

.view.active {
  display: block;
}

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

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

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

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

.panel {
  padding: 20px;
}

.card {
  padding: 18px;
}

.hero-band {
  display: grid;
  grid-template-columns: minmax(0, 1.2fr) minmax(260px, 0.8fr);
  gap: 16px;
  align-items: stretch;
  margin-bottom: 16px;
}

.today-plan {
  min-height: 260px;
  padding: 26px;
  border-radius: var(--radius);
  background: linear-gradient(135deg, #174b3d 0%, #246f59 52%, #f2bd5c 100%);
  color: #fff;
  box-shadow: var(--shadow);
}

.today-plan .muted {
  color: rgba(255, 255, 255, 0.78);
}

.hero-copy {
  max-width: 640px;
  color: rgba(255, 255, 255, 0.86);
  font-size: 17px;
  line-height: 1.65;
}

.task-list {
  display: grid;
  gap: 10px;
  margin: 18px 0;
}

.task-item {
  display: grid;
  grid-template-columns: 34px minmax(0, 1fr) auto;
  gap: 10px;
  align-items: center;
  padding: 10px 12px;
  border-radius: var(--radius);
  background: rgba(255, 255, 255, 0.16);
}

.task-index {
  display: grid;
  width: 30px;
  height: 30px;
  place-items: center;
  border-radius: 99px;
  background: rgba(255, 255, 255, 0.18);
  font-weight: 800;
}

.task-time {
  color: rgba(255, 255, 255, 0.8);
  font-weight: 700;
  white-space: nowrap;
}

.classroom-flow {
  margin-bottom: 16px;
}

.flow-strip,
.mini-flow {
  display: grid;
  gap: 10px;
}

.flow-strip {
  grid-template-columns: repeat(5, minmax(0, 1fr));
}

.mini-flow {
  grid-template-columns: repeat(4, minmax(0, 1fr));
  margin-bottom: 16px;
}

.flow-step {
  display: grid;
  min-height: 118px;
  align-content: start;
  gap: 8px;
  padding: 14px;
  border: 1px solid var(--line);
  border-radius: var(--radius);
  background: linear-gradient(180deg, #ffffff 0%, #f4f8fb 100%);
}

.flow-step span {
  display: grid;
  width: 30px;
  height: 30px;
  place-items: center;
  border-radius: 99px;
  background: #eaf1ff;
  color: var(--blue);
  font-weight: 850;
}

.flow-step strong {
  font-size: 17px;
}

.flow-step small {
  color: var(--muted);
  line-height: 1.45;
}

.support-note {
  margin: 14px 0 0;
  padding: 12px 14px;
  border-radius: var(--radius);
  background: #fff8ea;
  color: #715020;
  line-height: 1.6;
}

.subject-tile {
  display: flex;
  min-height: 132px;
  flex-direction: column;
  justify-content: space-between;
  cursor: pointer;
}

.subject-tile.primary {
  border-color: rgba(37, 111, 91, 0.35);
}

.subject-tile.disabled {
  color: var(--muted);
  box-shadow: none;
  cursor: default;
}

.badge,
.chip,
.pill {
  display: inline-flex;
  align-items: center;
  width: fit-content;
  min-height: 28px;
  padding: 5px 10px;
  border-radius: 999px;
  background: var(--panel-soft);
  color: var(--green-dark);
  font-size: 13px;
  font-weight: 700;
}

.badge.amber {
  background: #fff0d8;
  color: #8a5318;
}

.badge.red {
  background: #fdebe8;
  color: #9f3932;
}

.badge.blue {
  background: #eaf1ff;
  color: #274f8f;
}

.primary-button,
.secondary-button,
.ghost-button,
.danger-button,
.file-label {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  min-height: 48px;
  padding: 0 18px;
  border-radius: var(--radius);
  cursor: pointer;
  font-weight: 800;
}

.primary-button {
  background: var(--green-dark);
  color: #fff;
}

.secondary-button {
  border: 1px solid var(--line);
  background: #fff;
  color: var(--ink);
}

.compact-button {
  min-height: 40px;
  padding: 9px 14px;
  white-space: nowrap;
}

.ghost-button {
  background: var(--panel-soft);
  color: var(--green-dark);
}

.danger-button {
  background: #fdebe8;
  color: #9f3932;
}

.stat-card {
  min-height: 120px;
}

.stat-value {
  display: block;
  margin-top: 8px;
  font-size: 32px;
  font-weight: 850;
}

.unit-row {
  display: grid;
  grid-template-columns: minmax(0, 1fr) auto;
  gap: 12px;
  align-items: center;
  padding: 14px 0;
  border-top: 1px solid var(--line);
}

.unit-row:first-child {
  border-top: 0;
}

.practice-stage {
  display: grid;
  min-height: 520px;
  grid-template-rows: auto minmax(0, 1fr) auto;
  gap: 16px;
}

.question-card {
  display: grid;
  place-items: center;
  min-height: 300px;
  padding: 28px;
  border: 1px solid var(--line);
  border-radius: var(--radius);
  background: #fff;
  text-align: center;
  box-shadow: var(--shadow);
}

.lesson-card {
  align-content: start;
  text-align: left;
}

.lesson-list {
  display: grid;
  width: min(760px, 100%);
  gap: 10px;
  margin: 18px auto 0;
}

.lesson-row {
  display: grid;
  grid-template-columns: minmax(0, 1fr) auto;
  gap: 12px;
  align-items: center;
  min-height: 62px;
  padding: 12px 14px;
  border: 1px solid var(--line);
  border-radius: var(--radius);
  background: #fff;
  color: var(--ink);
  text-align: left;
  cursor: pointer;
}

.lesson-row:hover,
.choice-button:hover,
.secondary-button:hover,
.ghost-button:hover {
  border-color: rgba(37, 111, 91, 0.35);
}

.lesson-row.is-playing {
  border-color: rgba(37, 111, 91, 0.45);
  background: #f7fbf7;
}

.question-word {
  margin-bottom: 10px;
  font-size: 54px;
  line-height: 1.05;
  font-weight: 850;
}

.fill-blank-prompt {
  width: min(760px, 100%);
  margin-inline: auto;
  font-size: 24px;
  line-height: 1.55;
  font-weight: 700;
  text-align: left;
}

.inline-blank {
  display: inline-block;
  width: 128px;
  max-width: 42vw;
  height: 0.9em;
  margin: 0 6px;
  vertical-align: -0.08em;
  border-bottom: 3px solid rgba(20, 83, 70, 0.72);
}

.question-zh {
  color: var(--muted);
  font-size: 22px;
}

.choice-grid {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 12px;
  width: min(640px, 100%);
}

.choice-button {
  min-height: 64px;
  padding: 12px;
  border: 1px solid var(--line);
  border-radius: var(--radius);
  background: #fff;
  cursor: pointer;
  font-weight: 800;
}

.choice-button.correct {
  border-color: #70b98e;
  background: #e9f7ee;
}

.choice-button.wrong {
  border-color: #e2ad5e;
  background: #fff6e6;
}

.choice-button:disabled {
  opacity: 0.88;
}

.answer-feedback {
  min-height: 32px;
  margin-top: 14px;
  color: var(--muted);
  font-weight: 800;
}

.answer-feedback.ok {
  color: var(--green-dark);
}

.answer-feedback.warn {
  color: #9f5f1c;
}

.text-input {
  width: min(460px, 100%);
  height: 58px;
  padding: 0 16px;
  border: 1px solid var(--line);
  border-radius: var(--radius);
  outline: none;
  font-size: 22px;
}

.text-input:focus,
textarea:focus,
select:focus {
  border-color: var(--green);
  box-shadow: 0 0 0 4px rgba(37, 111, 91, 0.12);
}

textarea,
select {
  width: 100%;
  border: 1px solid var(--line);
  border-radius: var(--radius);
  background: #fff;
}

textarea {
  min-height: 92px;
  padding: 12px;
  resize: vertical;
}

select {
  height: 48px;
  padding: 0 12px;
}

.meter {
  overflow: hidden;
  width: 100%;
  height: 10px;
  border-radius: 99px;
  background: var(--panel-soft);
}

.meter span {
  display: block;
  width: var(--value);
  height: 100%;
  border-radius: inherit;
  background: var(--green);
}

.mistake-list,
.report-list {
  display: grid;
  gap: 10px;
}

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

.mistake-category-card {
  display: grid;
  gap: 12px;
  align-content: space-between;
  min-height: 172px;
  padding: 14px;
  border: 1px solid var(--line);
  border-radius: var(--radius);
  background: var(--panel-soft);
}

.mistake-item,
.report-item {
  display: grid;
  grid-template-columns: minmax(0, 1fr) auto;
  gap: 12px;
  align-items: center;
  padding: 12px;
  border: 1px solid var(--line);
  border-radius: var(--radius);
  background: #fff;
}

.letter-answer {
  display: flex;
  align-items: center;
  justify-content: center;
  min-height: 54px;
  margin: 14px auto;
  padding: 10px 14px;
  border: 1px solid var(--line);
  border-radius: var(--radius);
  background: #fff;
  color: var(--ink);
  font-size: 24px;
  font-weight: 800;
  letter-spacing: 0.04em;
  white-space: pre-wrap;
}

.letter-answer:empty::before {
  content: "点下面字母作答";
  color: var(--muted);
  font-size: 16px;
  font-weight: 600;
  letter-spacing: 0;
}

.letter-answer.locked {
  background: var(--panel-soft);
}

.letter-keyboard {
  display: flex;
  flex-direction: column;
  gap: 8px;
  max-width: 620px;
  margin: 0 auto;
}

.keyboard-row {
  display: grid;
  gap: 8px;
}

.keyboard-row-1 {
  grid-template-columns: repeat(10, minmax(0, 1fr));
}

.keyboard-row-2 {
  grid-template-columns: repeat(9, minmax(0, 1fr));
  padding: 0 5%;
}

.keyboard-row-3 {
  grid-template-columns: repeat(7, minmax(0, 1fr));
  padding: 0 14%;
}

.keyboard-symbol-row {
  grid-template-columns: repeat(6, minmax(0, 1fr));
  padding: 0 18%;
}

.keyboard-action-row {
  grid-template-columns: 1.1fr 2fr 1.1fr;
}

.letter-key {
  min-height: 46px;
  border: 1px solid var(--line);
  border-radius: var(--radius);
  background: #fff;
  color: var(--ink);
  font-weight: 800;
  text-transform: uppercase;
  cursor: pointer;
}

.letter-key.utility {
  text-transform: none;
}

.letter-key.symbol {
  text-transform: none;
}

.letter-key.confirm {
  background: var(--green-dark);
  color: #fff;
  text-transform: none;
}

.recording-panel {
  display: grid;
  gap: 16px;
}

.mic-button {
  display: grid;
  width: min(280px, 70vw);
  aspect-ratio: 1;
  place-items: center;
  justify-self: center;
  border-radius: 999px;
  background: var(--green-dark);
  color: #fff;
  cursor: pointer;
  box-shadow: 0 22px 55px rgba(24, 76, 62, 0.25);
}

.mic-button.recording {
  background: var(--red);
}

.mic-button strong {
  font-size: 26px;
}

.score-grid {
  display: grid;
  grid-template-columns: repeat(4, minmax(0, 1fr));
  gap: 10px;
}

.score-box {
  padding: 12px;
  border-radius: var(--radius);
  background: var(--panel-soft);
}

.score-box strong {
  display: block;
  font-size: 28px;
}

.field-row > * {
  flex: 1 1 190px;
}

.field-label {
  display: grid;
  gap: 8px;
  color: var(--muted);
  font-weight: 700;
}

.setting-stack {
  display: grid;
  gap: 14px;
}

.student-settings {
  margin-top: 16px;
  padding-top: 16px;
  border-top: 1px solid var(--line);
}

.export-callout {
  display: grid;
  grid-template-columns: minmax(0, 1fr) auto;
  gap: 14px;
  align-items: center;
  margin-top: 16px;
  padding: 16px;
  border: 1px solid rgba(37, 111, 91, 0.22);
  border-radius: var(--radius);
  background: #f4fbf7;
}

.export-callout strong,
.export-callout span {
  display: block;
}

.export-callout span,
.support-line {
  color: var(--muted);
}

.support-line {
  margin: 12px 0 0;
  line-height: 1.55;
}

.speaking-scope {
  margin-bottom: 14px;
}

.setting-line {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 14px;
}

input[type="range"] {
  width: 100%;
  accent-color: var(--green);
}

.standards-grid {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 10px;
}

.daily-summary-grid {
  display: grid;
  grid-template-columns: repeat(4, minmax(0, 1fr));
  gap: 10px;
  margin-top: 14px;
}

.standard-item {
  min-height: 106px;
  padding: 14px;
  border: 1px solid var(--line);
  border-radius: var(--radius);
  background: var(--panel-soft);
}

.standard-item strong {
  display: block;
  margin: 6px 0;
  font-size: 28px;
}

.toast {
  position: fixed;
  right: 24px;
  bottom: 24px;
  z-index: 20;
  max-width: min(420px, calc(100vw - 48px));
  padding: 13px 16px;
  border-radius: var(--radius);
  background: #17231d;
  color: #fff;
  opacity: 0;
  transform: translateY(10px);
  transition: opacity 0.18s ease, transform 0.18s ease;
}

.toast.show {
  opacity: 1;
  transform: translateY(0);
}

@media (max-width: 860px) {
  .shell {
    grid-template-columns: 1fr;
    align-content: start;
  }

  .sidebar {
    position: static;
    align-self: start;
    height: auto;
    padding: 14px;
    border-right: 0;
    border-bottom: 1px solid var(--line);
  }

  .brand,
  .sync-panel {
    display: none;
  }

  .nav {
    grid-template-columns: repeat(5, 1fr);
  }

  .nav-item {
    text-align: center;
  }

  .main {
    padding: 18px;
  }

  h1 {
    font-size: 27px;
  }

  .hero-band,
  .grid.two,
  .grid.three,
  .flow-strip,
  .mini-flow,
  .mistake-category-grid,
  .score-grid,
  .standards-grid,
  .daily-summary-grid,
  .export-callout {
    grid-template-columns: 1fr;
  }

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

  .letter-keyboard,
  .keyboard-row {
    gap: 6px;
  }

  .keyboard-row-1,
  .keyboard-row-2,
  .keyboard-row-3,
  .keyboard-symbol-row {
    grid-template-columns: repeat(5, minmax(0, 1fr));
    padding: 0;
  }

  .keyboard-action-row {
    grid-template-columns: 1fr;
  }

  .question-word {
    font-size: 42px;
  }

  .fill-blank-prompt {
    font-size: 20px;
    line-height: 1.5;
  }

  .inline-blank {
    width: 96px;
  }
}