.vw-root { --vw-green: #16776c; --vw-ink: #173c37; --vw-muted: #61746f; --vw-border: #d7e5df; box-sizing: border-box; max-width: 1050px; margin: 0 auto; padding: 28px 24px 56px; color: var(--vw-ink); font: 16px/1.65 system-ui, -apple-system, "Segoe UI", "PingFang SC", "Microsoft YaHei", sans-serif; }
.vw-root *, .vw-root *::before, .vw-root *::after { box-sizing: border-box; }
.vw-root h1, .vw-root h2, .vw-root h3, .vw-root p { margin: 0; }
.vw-root h1 { font-size: 24px; letter-spacing: -.5px; }
.vw-root h2 { font-size: clamp(25px, 4vw, 34px); line-height: 1.3; margin: 5px 0 12px; }
.vw-root h3 { font-size: 19px; }
.vw-root button, .vw-root input, .vw-root select { font: inherit; }
.vw-root button { cursor: pointer; }
.vw-root button:disabled { cursor: not-allowed; opacity: .52; }
.vw-root :focus-visible { outline: 3px solid #d39e23; outline-offset: 4px; }
.vw-root [data-focus]:focus:not(:focus-visible) { outline: none; }
.vw-header, .vw-session-top, .vw-library-title { display: flex; justify-content: space-between; align-items: center; gap: 16px; }
.vw-header { padding-bottom: 18px; border-bottom: 1px solid var(--vw-border); }
.vw-eyebrow { color: var(--vw-green); font-size: 12px; font-weight: 700; letter-spacing: 1px; }
.vw-label { display: inline-block; color: var(--vw-green); background: #e5f1ec; padding: 5px 11px; border-radius: 6px; font-size: 13px; }
.vw-save { min-height: 39px; padding-top: 8px; font-size: 13px; color: var(--vw-muted); }
.vw-heading { padding: 22px 0 25px; }
.vw-muted { color: var(--vw-muted); font-size: 14px; }
.vw-books { display: grid; grid-template-columns: 1fr 1fr; gap: 16px; margin-bottom: 20px; }
.vw-book { display: flex; flex-direction: column; align-items: flex-start; gap: 4px; padding: 21px; background: #fff; border: 1px solid var(--vw-border); border-radius: 12px; text-align: left; color: var(--vw-ink); }
.vw-book.is-selected { border: 2px solid var(--vw-green); background: #f2f8f4; padding: 20px; }
.vw-book > span:first-child { font-weight: 700; }
.vw-book strong { font-size: 31px; line-height: 1.5; }
.vw-book small { font-size: 14px; font-weight: 400; }
.vw-panel { background: #fff; border: 1px solid var(--vw-border); border-radius: 12px; padding: 24px; margin-bottom: 20px; }
.vw-stats { display: grid; grid-template-columns: repeat(3, 1fr); gap: 16px; margin-bottom: 23px; }
.vw-stats > div { display: flex; flex-direction: column; padding-right: 10px; }
.vw-stats > div + div { border-left: 1px solid var(--vw-border); padding-left: 22px; }
.vw-stats strong { font-size: 30px; line-height: 1.4; font-weight: 650; }
.vw-stats span { font-size: 14px; color: var(--vw-muted); }
.vw-settings { display: flex; flex-wrap: wrap; gap: 16px; align-items: flex-end; padding-top: 22px; border-top: 1px solid var(--vw-border); }
.vw-settings label { flex: 1; min-width: 160px; font-size: 13px; color: var(--vw-muted); }
.vw-root input:not([type="radio"]), .vw-root select { display: block; width: 100%; min-height: 46px; border: 1px solid #bbcfc5; border-radius: 6px; padding: 9px 12px; background: #fff; color: var(--vw-ink); margin-top: 5px; }
.vw-button { min-height: 46px; padding: 10px 20px; border: 1px solid transparent; border-radius: 7px; font-size: 15px; font-weight: 650; }
.vw-primary { background: var(--vw-green); color: #fff; }
.vw-primary:hover:not(:disabled) { background: #105d54; }
.vw-secondary { background: #fff; color: var(--vw-green); border-color: #a7c7b8; }
.vw-text { background: transparent; color: var(--vw-green); padding-left: 4px; padding-right: 4px; }
.vw-actions { margin-top: 23px; margin-bottom: 10px; }
.vw-actions .vw-button { min-width: 190px; }
.vw-search { display: block; font-size: 13px; color: var(--vw-muted); margin: 18px 0 10px; }
.vw-word-row { display: grid; grid-template-columns: minmax(150px, 1fr) 2fr; gap: 20px; padding: 14px 0; border-bottom: 1px solid #e9f0ec; }
.vw-word-row strong { display: block; font-size: 17px; }
.vw-word-row p { font-size: 14px; white-space: pre-line; }
.vw-phonetic { color: var(--vw-muted); font-size: 14px; }
.vw-word-list + .vw-muted { margin-top: 12px; }
.vw-method { max-width: 760px; color: var(--vw-muted); font-size: 13px; }
.vw-session-top { font-size: 13px; color: var(--vw-muted); padding-top: 10px; }
.vw-timer { display: flex; align-items: center; justify-content: flex-end; gap: 12px; color: var(--vw-muted); font-size: 13px; font-variant-numeric: tabular-nums; }
.vw-timer .vw-button { font-size: 13px; }
.vw-study-duration { font-weight: 650; margin: 16px 0 8px !important; }
.vw-history { margin: 12px 0; padding: 0; list-style: none; }
.vw-history li { display: flex; justify-content: space-between; flex-wrap: wrap; gap: 5px 15px; padding: 12px 0; border-bottom: 1px solid var(--vw-border); font-size: 14px; }
.vw-history span { color: var(--vw-muted); }
.vw-progress { width: 100%; height: 7px; border: 0; margin-bottom: 20px; accent-color: var(--vw-green); }
.vw-progress::-webkit-progress-bar { background: #deebe4; border-radius: 5px; }
.vw-progress::-webkit-progress-value { background: var(--vw-green); border-radius: 5px; }
.vw-study-card { max-width: 740px; margin: 0 auto 24px; padding: 30px; }
.vw-study-card > .vw-label { margin-bottom: 16px; }
.vw-study-card .vw-word { font-size: clamp(34px, 7vw, 48px); line-height: 1.25; overflow-wrap: anywhere; }
.vw-study-card > .vw-phonetic { margin: 7px 0 17px; }
.vw-definition { font-size: 19px; margin: 18px 0 !important; white-space: pre-line; }
.vw-study-card > .vw-muted { margin: 20px 0 14px; }
.vw-study-card > .vw-primary:last-child { display: block; width: 100%; margin-top: 18px; }
.vw-study-card .vw-prompt { font-size: 27px; margin: 7px 0 24px; overflow-wrap: anywhere; white-space: pre-line; }
.vw-options { padding: 0; margin: 0 0 20px; border: 0; display: grid; gap: 12px; }
.vw-option { display: flex; align-items: center; gap: 11px; min-height: 56px; padding: 12px 15px; border: 1px solid var(--vw-border); border-radius: 7px; cursor: pointer; }
.vw-option.is-selected { border-color: var(--vw-green); background: #edf6f0; }
.vw-option.is-correct { border-color: #268350; background: #e9f5e9; }
.vw-option input { accent-color: var(--vw-green); width: 19px; height: 19px; margin: 0; flex-shrink: 0; }
.vw-option-index { color: var(--vw-muted); font-size: 13px; }
.vw-feedback { margin: 22px 0 15px; padding: 17px; border-radius: 7px; background: #eef5e8; border-left: 4px solid #588344; }
.vw-feedback.is-wrong { background: #fbf0e8; border-color: #b46c37; }
.vw-feedback p { font-size: 15px; margin-top: 7px; white-space: pre-line; }
.vw-ratings { display: grid; grid-template-columns: repeat(3, 1fr); gap: 12px; margin-top: 15px; }
.vw-ratings .vw-button { padding-left: 9px; padding-right: 9px; }
.vw-spelling { display: block; color: var(--vw-muted); font-size: 14px; margin-bottom: 20px; }
.vw-spelling input { font-size: 22px !important; }
.vw-next-due { color: var(--vw-green); font-size: 14px; margin-top: 18px !important; }
.vw-error { color: #9b371c; background: #fff0e9; padding: 12px; border-radius: 6px; font-size: 14px; }
.vw-sr-only { position: absolute; width: 1px; height: 1px; margin: -1px; overflow: hidden; clip: rect(0, 0, 0, 0); white-space: nowrap; }
@media (max-width: 620px) {
  .vw-root { padding: 18px 14px 35px; }
  .vw-header { align-items: flex-start; }
  .vw-header > .vw-label { max-width: 110px; text-align: center; font-size: 12px; }
  .vw-books { gap: 10px; }
  .vw-book { padding: 15px; }
  .vw-book.is-selected { padding: 14px; }
  .vw-book .vw-muted { font-size: 12px; }
  .vw-book strong { font-size: 26px; }
  .vw-panel, .vw-study-card { padding: 19px 16px; }
  .vw-stats { gap: 8px; }
  .vw-stats > div + div { padding-left: 12px; }
  .vw-stats strong { font-size: 26px; }
  .vw-stats span { font-size: 12px; }
  .vw-settings { gap: 12px; }
  .vw-settings label { min-width: 110px; }
  .vw-settings .vw-button, .vw-actions .vw-button { width: 100%; }
  .vw-word-row { grid-template-columns: 1fr; gap: 3px; }
  .vw-word-row strong, .vw-word-row .vw-phonetic { display: inline; margin-right: 8px; }
  .vw-library-title { align-items: flex-start; }
  .vw-library-title .vw-muted { font-size: 12px; }
  .vw-ratings { gap: 7px; }
  .vw-ratings .vw-button { font-size: 14px; }
  .vw-study-card .vw-prompt { font-size: 23px; }
  .vw-session-top { gap: 10px; font-size: 12px; }
}