/* Screens 05, 06, 07, 08 and 12. Geometry normalized from LayerLab source PNGs to 426px. */
html:has(.study-design) { scrollbar-width: none; }
html:has(.study-design)::-webkit-scrollbar { display: none; }
.study-design {
  --study-blue: #126bff;
  --study-ink: #071138;
  --study-muted: #7b87a7;
  --study-border: #dce7f8;
  box-sizing: border-box;
  position: relative;
  max-width: 426px;
  min-height: 100dvh;
  margin: 0 auto;
  padding: calc(14px + env(safe-area-inset-top)) 18px calc(24px + env(safe-area-inset-bottom));
  overflow: visible;
  color: var(--study-ink);
}
.study-design *, .study-design *::before, .study-design *::after { box-sizing: border-box; }
.study-design button, .study-design input, .study-design textarea { font: inherit; }
.study-design button { cursor: pointer; }
.study-design button:disabled { cursor: default; opacity: .45; }
.study-design h1, .study-design h2, .study-design h3, .study-design p, .study-design figure { margin: 0; }
.study-design h1 { font-size: 24px; font-weight: 780; line-height: 1.35; letter-spacing: -.75px; }
.study-design h2 { font-size: 19px; font-weight: 740; line-height: 1.4; letter-spacing: -.4px; }
.study-design h3 { font-size: 16px; line-height: 1.5; }
.study-design p { line-height: 1.55; }
.study-design .card { border: 1px solid #fff; border-radius: 19px; padding: 17px; margin: 0 0 14px; box-shadow: 0 8px 20px #78b3ec09; background: #fff; }
.study-design .button { display: inline-flex; align-items: center; justify-content: center; gap: 9px; min-height: 48px; padding: 10px 14px; border: 1px solid transparent; border-radius: 12px; font-size: 17px; font-weight: 650; line-height: 1.3; text-align: center; white-space: normal; }
.study-design .button.primary { color: #fff; border-color: #096dff; background: linear-gradient(105deg,#0876ff,#1769ff); box-shadow: 0 5px 13px #2f80ef10; }
.study-design .button.secondary { color: #5d6f94; background: #fff; border-color: #cbdaf2; }
.study-design .button.ghost { color: #6e7fa5; background: transparent; border-color: transparent; }
.study-design .button.full { width: 100%; }
.study-design .field { width: 100%; min-width: 0; border: 1px solid #d1dff4; border-radius: 12px; background: #fff; padding: 14px; color: var(--study-ink); font-size: 16px; line-height: 1.6; resize: vertical; }
.study-design .field::placeholder, .study-design textarea::placeholder { color: #9aa6bf; }
.study-design .rich-text { font-size: inherit; line-height: 1.65; overflow-wrap: anywhere; }
.study-design .rich-text p + p { margin-top: 13px; }
.study-design .rich-text h2, .study-design .rich-text h3, .study-design .rich-text h4 { margin: 16px 0 8px; }
.study-design .authored-content table { max-width: 100%; border-collapse: collapse; font-size: .9em; }
.study-design .authored-content th, .study-design .authored-content td { padding: 6px; border: 1px solid var(--study-border); }
.study-design .authored-content svg, .study-design .authored-content img { display: block; max-width: 100%; height: auto; margin: 12px auto; }
.study-design .study-header { display: grid; grid-template-columns: 29px minmax(0,1fr) 27px; align-items: center; gap: 10px; min-height: 49px; margin: 0 0 21px; }
.study-design .study-header > div { min-width: 0; }
.study-design .study-header h1 { text-align: center; }
.study-design .study-header p { margin-top: 5px; font-size: 12px; color: var(--study-muted); }
.study-design .study-header .study-back { margin-left: -5px; }
.study-design .study-back, .study-design .study-bookmark { display: grid; place-items: center; background: transparent; border: 0; padding: 4px; color: #1b2c5a; min-height: 42px; }
.study-design .study-bookmark.is-bookmarked { color: var(--study-blue); }
.study-design .study-bookmark.is-bookmarked path { fill: #d9eaff; }
.study-design .study-art { width: 25px; height: 25px; object-fit: contain; display: inline-block; flex: 0 0 auto; }
.study-design .study-robot { display: block; flex: 0 0 auto; height: auto; object-fit: contain; }
.study-design .study-chip { display: inline-flex; align-items: center; justify-content: center; width: max-content; padding: 5px 11px; border-radius: 100px; background: #eaf3ff; color: var(--study-blue); font-size: 12px; font-weight: 650; line-height: 1.4; white-space: nowrap; }
.study-design .study-tabs { display: flex; width: 100%; padding: 2px; background: #e8f1fc; border: 1px solid #edf4fe; border-radius: 13px; margin-bottom: 14px; }
.study-design .study-tabs button { flex: 1; min-width: 0; min-height: 40px; padding: 8px 3px; border: 1px solid transparent; border-radius: 11px; color: #6e7da0; font-size: 15px; font-weight: 660; line-height: 1.35; background: transparent; }
.study-design .study-tabs button.selected { color: var(--study-blue); background: #fff; border-color: #4a87ff; box-shadow: 0 2px 5px #67a4f210; }
.study-design .study-actions { display: flex; gap: 13px; }
.study-design .study-actions > * { flex: 1; min-width: 0; }
.study-design progress { -webkit-appearance: none; appearance: none; border: 0; background: #e1ebf8; border-radius: 100px; height: 13px; overflow: hidden; }
.study-design progress::-webkit-progress-bar { background: #e1ebf8; border-radius: 100px; }
.study-design progress::-webkit-progress-value { border-radius: 100px; background: linear-gradient(90deg,#1172ff,#3683ff); }
.study-design progress::-moz-progress-bar { border-radius: 100px; background: #1675ff; }
.study-design .study-bubble { position: relative; background: #eef5fe; border-radius: 19px; padding: 15px 17px; font-size: 16px; line-height: 1.55; }
.study-design .study-bubble::before { content: ""; position: absolute; left: -9px; top: 35%; width: 17px; height: 17px; transform: rotate(45deg); background: inherit; }
.study-design .study-pending { padding: 12px 4px; color: #6d7b9f; font-size: 13px; }
.study-design [data-study-feedback]:empty { display: none; }
.study-design [data-study-feedback] .card { border: 1px solid #dbe7fa; font-size: 13px; padding: 12px; margin: 10px 0; }
/* Shared working composer; labels and input remain editable. */
.study-design .study-composer { display: flex; align-items: center; gap: 9px; width: 100%; }
.study-design .study-composer textarea { display: block; flex: 1; min-width: 0; height: 44px; max-height: 112px; resize: none; scrollbar-width: none; border: 1px solid #d7e5f9; background: #fff; border-radius: 22px; padding: 11px 13px; color: #15234b; font-size: 14px; line-height: 20px; }
.study-design .study-composer textarea::-webkit-scrollbar { display: none; }
.study-design .study-mic, .study-design .study-send { display: grid; place-items: center; flex: 0 0 44px; width: 44px; height: 44px; padding: 0; border: 1px solid #e0ebfc; border-radius: 50%; background: #fff; color: var(--study-blue); }
.study-design .study-mic img { height: 28px; width: 24px; }
.study-design .study-send { background: linear-gradient(130deg,#3787ff,#126bff); border-color: transparent; color: #fff; }
.study-design .study-send[aria-busy="true"] { animation: study-pulse 1s ease-in-out infinite alternate; }
.study-design .study-speech-state { margin: 3px 0 0; font-size: 11px; color: #6b7c9d; min-height: 0; }
.study-design .study-speech-state:empty { display: none; }
@keyframes study-pulse { to { opacity: .5; } }
/* 05: textbook tabs, authored content and the bottom tutor sheet. */
.study-reader { padding-bottom: 223px; }
.study-reader .reader-header { display: flex; gap: 13px; min-height: 38px; margin-bottom: 14px; }
.study-reader .reader-breadcrumb { display: flex; align-items: center; gap: 10px; flex: 1; color: #7c87a6; font-size: 15px; font-weight: 620; }
.study-reader .reader-breadcrumb span { font-size: 23px; line-height: 1; }
.study-reader .reader-title { font-size: 26px; line-height: 1.4; margin: 0 4px 18px; }
.study-reader .reader-progress { display: flex; gap: 13px; align-items: center; margin: 13px 1px 20px; }
.study-reader .reader-progress progress { flex: 1; min-width: 0; }
.study-reader .reader-progress progress::-webkit-progress-value { background: linear-gradient(90deg,#03c476,#1dcc88); }
.study-reader .reader-progress span { color: #7c87a6; font-size: 16px; }
.study-reader .reader-card { padding: 14px 15px 13px; }
.study-reader .reader-card > header { display: flex; align-items: center; gap: 10px; margin-bottom: 15px; }
.study-reader .reader-card > header h2 { flex: 1; min-width: 0; font-size: 19px; }
.study-reader .reader-section-icon { width: 33px; height: 33px; border-radius: 50%; background: #e4fbf1; display: grid; place-items: center; flex: 0 0 auto; }
.study-reader .reader-section-icon img { width: 22px; height: 21px; }
.study-reader .reader-body { line-height: 1.65; }
.study-reader .reader-body .rich-text { font-size: inherit; }
.study-reader .reader-body blockquote { margin: 14px 0; padding: 14px 16px; border-radius: 16px; background: #eff6ff; }
.study-reader .reader-body blockquote h3 { margin: 0 0 9px; }
.study-reader .reader-body blockquote p { margin-top: 8px; color: #5c6f96; }
.study-reader .reader-body blockquote p:has(> i:only-child) { text-align: center; color: var(--study-ink); font-family: Georgia, "Times New Roman", serif; font-size: 28px; }
.study-reader .reader-connection { margin: 16px 0 0; padding: 13px; border-radius: 13px; background: #eef6ff; display: flex; gap: 10px; align-items: flex-start; font-size: .92em; }
.study-reader .reader-connection > span { flex: 0 0 29px; }
.study-reader .reader-connection h3 { margin-bottom: 6px; }
.study-reader .reader-caution { margin-top: 12px; padding: 12px; border-radius: 12px; background: #fff6e8; font-size: .9em; }
.study-reader .reader-pagination { margin: 14px 0; }
.study-reader .reader-settings { color: #7c88a4; font-size: 12px; margin: 16px 0; }
.study-reader .reader-settings summary { cursor: pointer; }
.study-reader .reader-settings .study-actions { margin-top: 9px; flex-wrap: wrap; }
.study-reader .reader-settings .button { min-height: 37px; font-size: 12px; padding: 7px; }
.study-reader .reader-tutor { position: fixed; bottom: 0; left: 50%; transform: translateX(-50%); z-index: 35; width: min(100%,426px); border: 2px solid #e0efff; border-radius: 28px 28px 0 0; background: #fff; padding: 6px 15px calc(13px + env(safe-area-inset-bottom)); box-shadow: 0 -3px 12px #6baaf214; }
.study-reader .drawer-handle { width: 38px; height: 4px; background: #c5cede; border-radius: 9px; margin: 0 auto 7px; }
.study-reader .reader-tutor > header { display: flex; align-items: center; gap: 7px; min-height: 28px; margin-bottom: 6px; }
.study-reader .reader-tutor > header h2 { font-size: 17px; }
.study-reader .reader-tutor > header button { margin-left: auto; color: #7b8dad; display: grid; place-items: center; min-width: 32px; min-height: 32px; }
.study-reader .reader-mic-dot { width: 26px; height: 26px; background: #edf5ff; border-radius: 50%; display: grid; place-items: center; color: var(--study-blue); }
.study-reader .reader-tutor-answer { display: flex; align-items: center; gap: 8px; margin: 0 0 6px; }
.study-reader .reader-tutor-answer .study-robot { width: 71px; height: 65px; object-fit: contain; }
.study-reader .reader-tutor-answer .study-bubble { flex: 1; font-size: 14px; padding: 12px 15px; max-height: 150px; overflow-y: auto; }
.study-reader .reader-tutor-answer .study-bubble::before { display: none; }
.study-reader .reader-tutor .study-composer { gap: 8px; }
.study-reader .reader-tutor .study-mic { order: 2; width: 32px; height: 32px; flex-basis: 32px; border: 0; background: #e9fbf4; }
.study-reader .reader-tutor .study-mic img { width: 16px; height: 23px; }
.study-reader .reader-tutor .study-send { order: 3; }
.study-reader .reader-tutor .study-composer textarea { font-size: 14px; padding-left: 13px; }
.study-reader .reader-tutor.collapsed { padding-bottom: calc(7px + env(safe-area-inset-bottom)); }
.study-reader:has(.reader-tutor.collapsed) { padding-bottom: 90px; }
/* 06: a tall exam page with native interactive answer choices. */
.study-diagnostic .study-header { margin-bottom: 24px; }
.study-design .study-question-progress { display: flex; align-items: center; justify-content: space-between; gap: 12px; margin: 0 2px 26px; }
.study-design .study-question-progress > div:first-child { display: flex; align-items: center; gap: 13px; min-width: 0; }
.study-design .study-question-progress progress { width: 135px; max-width: 31vw; height: 14px; }
.study-design .study-question-progress span { font-size: 18px; color: #647496; }
.study-design .study-timer { display: flex; align-items: center; gap: 8px; }
.study-design .study-timer img { width: 22px; height: 25px; }
.study-design .study-timer span { font-size: 19px; font-variant-numeric: tabular-nums; }
.study-design .study-question-card { min-height: 580px; padding: 18px 16px 22px; display: flex; flex-direction: column; }
.study-diagnostic .study-question-card { min-height: clamp(490px,68dvh,656px); }
.study-design .study-question-card > header { display: flex; align-items: center; gap: 19px; margin-bottom: 28px; }
.study-design .study-question-card > header h2 { font-size: 22px; line-height: 1.5; }
.study-design .question-number { display: grid; place-items: center; width: 42px; height: 42px; flex: 0 0 42px; border-radius: 50%; background: linear-gradient(135deg,#087aff,#225aff); color: #fff; font-size: 25px; font-weight: 650; }
.study-design .study-question-body { font-size: 20px; line-height: 1.6; margin: 0 5px 28px; }
.study-design .study-question-body .authored-content + .authored-content { margin-top: 18px; }
.study-design .question-figure { margin: 16px 0; }
.study-design .study-choices { display: flex; flex-direction: column; gap: 3px; margin: 0 -5px; }
.study-design .study-choice { display: flex; gap: 13px; align-items: center; min-height: 56px; width: 100%; border: 1px solid transparent; border-radius: 15px; background: transparent; padding: 9px 11px; color: #101a3f; text-align: left; font-size: 21px; line-height: 1.45; }
.study-design .study-choice > span:last-child { min-width: 0; overflow-wrap: anywhere; }
.study-design .study-choice.selected { color: #1256ff; background: linear-gradient(110deg,#e7f3ff,#e9f4ff); }
.study-design .choice-radio { flex: 0 0 33px; width: 33px; height: 33px; border: 2px solid #bfcde3; border-radius: 50%; padding: 4px; }
.study-design .study-choice.selected .choice-radio { border-color: #1773ff; background: radial-gradient(circle,#1573ff 0 59%,#fff 62% 100%); box-shadow: 0 0 0 3px #d6e8ff; }
.study-design .choice-number { color: #95a3bf; font-size: 26px; line-height: 1; }
.study-design .study-choice.selected .choice-number { color: #176fff; }
.study-design .study-answer { min-height: 200px; }
.study-design .problem-navigation { margin: 19px 3px 0; }
.study-design .problem-navigation .button { min-height: 58px; font-size: 18px; }
.study-design .study-response-count { margin: 9px 0 0; color: #8693ad; font-size: 11px; text-align: center; }
.study-design .study-grade { margin-top: 16px; padding: 14px; border: 1px solid #c8ebdc; border-radius: 13px; background: #edfbf4; }
.study-design .study-grade.answer-wrong { border-color: #f8d5d7; background: #fff1f2; }
.study-design .study-grade h3 { margin-bottom: 9px; }
.study-design .study-grade .muted { margin-top: 12px; }
.study-design .practice-grade-action { margin-top: 12px; }
/* 07: real photo, annotation canvas and six working drawing tools. */
.study-camera .study-tabs { margin-bottom: 12px; }
.study-camera .photo-stage { position: relative; width: 100%; aspect-ratio: 782 / 948; border-radius: 20px; background: linear-gradient(135deg,#f4f8ff,#e4effa); overflow: hidden; isolation: isolate; }
.study-camera .photo-stage.has-photo { aspect-ratio: auto; max-height: 530px; overflow: auto; }
.study-camera .photo-surface { position: relative; width: 100%; display: block; }
.study-camera .photo-surface > img { display: block; width: 100%; height: auto; }
.study-camera .photo-surface > canvas { position: absolute; left: 0; top: 0; width: 100%; height: 100%; }
.study-camera .photo-empty { display: flex; align-items: center; justify-content: center; flex-direction: column; gap: 12px; position: absolute; inset: 0; cursor: pointer; color: #7b8cad; }
.study-camera .photo-empty img { width: 42px; height: 38px; }
.study-camera .photo-empty strong { color: #566b94; font-size: 17px; }
.study-camera .photo-empty span { font-size: 13px; }
.study-design .study-file-input { position: absolute; inset: 0; width: 100%; height: 100%; opacity: 0; cursor: pointer; }
.study-camera .photo-scan-frame { position: absolute; inset: 17.5% 4.6% 19.5%; pointer-events: none; }
.study-camera .photo-scan-frame i { position: absolute; width: 34px; height: 34px; border: 3px solid #2781ff; filter: drop-shadow(0 0 1px #fff) drop-shadow(0 0 1px #fff); }
.study-camera .photo-scan-frame i:nth-child(1) { left: 0; top: 0; border-right: 0; border-bottom: 0; border-radius: 16px 0 0 0; }
.study-camera .photo-scan-frame i:nth-child(2) { right: 0; top: 0; border-left: 0; border-bottom: 0; border-radius: 0 16px 0 0; }
.study-camera .photo-scan-frame i:nth-child(3) { left: 0; bottom: 0; border-right: 0; border-top: 0; border-radius: 0 0 0 16px; }
.study-camera .photo-scan-frame i:nth-child(4) { right: 0; bottom: 0; border-left: 0; border-top: 0; border-radius: 0 0 16px 0; }
.study-camera .photo-guide { position: absolute; bottom: 26px; left: 50%; transform: translateX(-50%); border-radius: 30px; background: #58617288; color: #fff; padding: 8px 16px; width: max-content; max-width: 86%; font-size: 11px; text-align: center; pointer-events: none; }
.study-camera .photo-status { display: flex; align-items: center; justify-content: center; gap: 13px; padding: 10px 13px; margin: 13px 0 10px; min-height: 63px; }
.study-camera .photo-status p { font-size: 14px; font-weight: 650; }
.study-camera .photo-status-mark { display: grid; place-items: center; flex: 0 0 45px; width: 45px; height: 45px; border-radius: 50%; border: 7px solid #e0fbf1; background: #05c987; color: white; font-size: 25px; line-height: 1; font-weight: 700; }
.study-camera .camera-tools { display: grid; grid-template-columns: repeat(6,minmax(0,1fr)); gap: 2px; padding: 12px 10px; background: #fff; border-radius: 19px; min-height: 99px; }
.study-camera .camera-tools button, .study-camera .camera-color { border: 0; border-radius: 11px; display: flex; flex-direction: column; align-items: center; justify-content: center; gap: 10px; padding: 8px 0; min-width: 0; color: #8493b2; background: transparent; position: relative; }
.study-camera .camera-tools .study-art { width: 27px; height: 27px; }
.study-camera .camera-tools span { font-size: 10px; white-space: nowrap; }
.study-camera .camera-tools button.selected { background: #eaf3ff; color: #126bff; }
.study-camera .camera-color i { display: block; width: 25px; height: 25px; border-radius: 50%; border: 1px solid #e3eaf8; }
.study-camera .camera-color input { position: absolute; inset: 0; width: 100%; height: 100%; opacity: 0; cursor: pointer; }
.study-camera .camera-actions { gap: 10px; margin-top: 12px; }
.study-camera .camera-actions .button { position: relative; min-height: 56px; padding: 10px 7px; font-size: 16px; }
.study-camera .camera-actions img { width: 26px; height: 23px; }
.study-camera .camera-question { margin: 11px 3px 0; font-size: 12px; color: #7a88a6; }
.study-camera .camera-question summary { cursor: pointer; }
.study-camera .camera-question textarea { margin-top: 10px; }
.study-camera .camera-text-question { min-height: 540px; display: flex; flex-direction: column; gap: 20px; }
.study-camera .camera-text-question textarea { flex: 1; }
.study-camera .camera-solution { margin-top: 20px; }
.study-camera .study-play { font-size: 19px; }
/* 08: numbered AI explanation. */
.study-ai { padding-bottom: 112px; }
.study-ai .study-header h1 { text-align: left; }
.study-ai .study-tabs { border-radius: 9px; gap: 1px; margin-bottom: 11px; }
.study-ai .study-tabs button { border-radius: 8px; min-height: 36px; }
.study-ai .ai-welcome { display: flex; align-items: center; gap: 13px; padding: 9px 13px; min-height: 100px; margin-bottom: 10px; }
.study-ai .ai-welcome .study-robot { width: 83px; height: 90px; }
.study-ai .ai-welcome > div { flex: 1; min-width: 0; }
.study-ai .ai-welcome h2 { font-size: 18px; margin-bottom: 4px; }
.study-ai .ai-welcome p { font-size: 14px; color: #526994; line-height: 1.45; }
.study-design .ai-solution { padding: 13px 13px 10px; }
.study-design .ai-solution-step { display: grid; grid-template-columns: 33px minmax(0,1fr); column-gap: 12px; margin: 0 0 20px; }
.study-design .ai-solution-step:last-child { margin-bottom: 0; }
.study-design .ai-step-number { display: grid; place-items: center; width: 33px; height: 33px; border-radius: 50%; color: #fff; font-size: 19px; font-weight: 700; background: linear-gradient(125deg,#1379ff,#0759ff); }
.study-design .ai-solution-step h2 { margin: 0 0 10px; min-height: 28px; padding: 3px 9px; border-radius: 30px; color: #086bff; background: #edf5ff; font-size: 17px; }
.study-design .ai-solution-step .rich-text { color: #243a68; font-size: 15px; line-height: 1.65; }
.study-design .rich-text .katex-display { margin: .5em 0; }
.study-design .ai-start { min-height: 350px; display: flex; flex-direction: column; justify-content: center; align-items: center; gap: 17px; text-align: center; }
.study-design .ai-start p { font-size: 14px; color: #7a89a8; }
.study-design .ai-related { display: flex; flex-direction: column; gap: 13px; }
.study-design .ai-related p { font-size: 14px; color: #7a89a8; }
.study-design .ai-concept-links h2 { margin-bottom: 14px; }
.study-design .ai-concept-links > button { display: flex; align-items: center; justify-content: space-between; gap: 12px; width: 100%; min-height: 44px; padding: 12px 0; color: #276fd9; border-bottom: 1px solid #e8f0fc; text-align: left; }
.study-design .ai-concept-links p { margin: 15px 0; color: #7a89a8; }
.study-design .ai-attachment { color: #7b8aaa; font-size: 12px; margin: 15px 2px; }
.study-design .ai-attachment summary { display: flex; align-items: center; gap: 7px; cursor: pointer; }
.study-design .ai-attachment .button { margin: 12px 0 0; min-height: 37px; font-size: 13px; }
.study-design .study-upload { display: block; position: relative; padding: 15px; margin-top: 10px; color: #1668d7; background: #fff; border: 1px dashed #b9cfee; border-radius: 11px; text-align: center; }
.study-design .ai-attachment-preview { display: block; width: 100%; max-height: 240px; object-fit: contain; border-radius: 12px; margin-top: 12px; }
.study-design .ai-composer-dock { position: fixed; z-index: 35; left: 50%; bottom: 0; transform: translateX(-50%); width: min(100%,426px); padding: 9px 17px calc(10px + env(safe-area-inset-bottom)); border-radius: 16px 16px 0 0; border-top: 1px solid #e5f0fc; background: #fff; }
.study-ai .study-mic { background: linear-gradient(140deg,#438dff,#2065fc); border-color: transparent; }
.study-ai .study-mic svg { color: #fff; }
/* 12: AI tutor, distinct from the human mentor screen. */
.study-tutor { padding: calc(16px + env(safe-area-inset-top)) 20px calc(205px + env(safe-area-inset-bottom)); min-height: 100dvh; }
.study-tutor .study-header { grid-template-columns: 28px minmax(0,1fr) 0; margin-bottom: 22px; }
.study-tutor .study-header h1 { font-size: 24px; text-align: left; }
.study-tutor .study-tabs { border-radius: 15px; padding: 2px; margin-bottom: 26px; }
.study-tutor .study-tabs button { min-height: 48px; border-radius: 14px; font-size: 18px; }
.study-tutor .tutor-chat { display: flex; flex-direction: column; gap: 18px; margin: 0 -3px 23px; }
.study-tutor .tutor-turn { display: flex; gap: 13px; align-items: center; }
.study-tutor .tutor-turn .study-robot { width: 82px; height: 108px; }
.study-tutor .tutor-turn .study-bubble { padding: 15px 16px; border-radius: 21px; background: #fff; font-size: 20px; flex: 0 1 auto; max-width: calc(100% - 93px); line-height: 1.35; }
.study-tutor .tutor-turn .rich-text { line-height: 1.35; }
.study-tutor .tutor-turn.mine { justify-content: flex-end; margin-left: 52px; }
.study-tutor .tutor-turn.mine .study-bubble { max-width: 100%; background: #e4f0ff; font-size: 17px; }
.study-tutor .tutor-turn.mine .study-bubble::before { left: auto; right: -6px; }
.study-tutor .tutor-suggestions { margin: 0 0 28px; padding: 13px 7px 10px; border: 1px solid #dceeff; border-radius: 18px; background: #e3f1ffbb; }
.study-tutor .tutor-suggestions h2 { display: flex; align-items: center; gap: 8px; padding: 0 5px; color: #0869dc; font-size: 15px; margin-bottom: 12px; }
.study-tutor .tutor-suggestions h2 svg { fill: #2682ff; color: #2682ff; }
.study-tutor .tutor-suggestions > div { display: flex; gap: 6px; }
.study-tutor .tutor-suggestions button { flex: 1; min-width: 0; padding: 10px 5px; min-height: 38px; color: #6d7a99; background: #fff; border: 1px solid #d5e2f7; border-radius: 24px; font-size: 11px; letter-spacing: -.5px; line-height: 1.4; white-space: nowrap; }
.study-tutor .tutor-composer-dock { position: fixed; z-index: 35; bottom: 0; left: 50%; transform: translateX(-50%); width: min(100%,426px); padding: 17px 20px calc(19px + env(safe-area-inset-bottom)); background: #fff; border-radius: 29px 29px 0 0; box-shadow: 0 -3px 18px #64a8eb09; }
.study-tutor .study-composer { gap: 10px; }
.study-tutor .study-mic, .study-tutor .study-send { width: 53px; height: 53px; flex-basis: 53px; box-shadow: 0 3px 10px #2074cc15; }
.study-tutor .study-composer textarea { height: 52px; padding: 14px 16px; font-size: 15px; }
.study-tutor .tutor-call { display: flex; justify-content: center; align-items: center; width: 100%; gap: 14px; min-height: 64px; margin: 14px 0 0; color: #fff; border: 0; border-radius: 14px; background: linear-gradient(110deg,#09c58a,#00ba7c); box-shadow: 0 6px 13px #00be8217; font-size: 20px; font-weight: 740; }
.study-tutor .tutor-call .study-art { width: 32px; height: 32px; }
.study-tutor .tutor-voice-hint { margin-top: 8px; font-size: 11px; text-align: center; color: #7788a6; }
@media (max-width: 374px) {
  .study-design { padding-left: 13px; padding-right: 13px; }
  .study-design .study-header h1, .study-reader .reader-title { font-size: 22px; }
  .study-design .study-tabs button { font-size: 13px; }
  .study-design .study-question-body { font-size: 18px; }
  .study-design .study-question-card > header h2 { font-size: 18px; }
  .study-design .study-choice { font-size: 18px; }
  .study-tutor .tutor-turn { gap: 9px; }
  .study-tutor .tutor-turn .study-robot { width: 67px; height: 89px; }
  .study-tutor .tutor-turn .study-bubble { max-width: calc(100% - 76px); font-size: 17px; }
  .study-tutor .tutor-suggestions button { font-size: 9px; padding: 9px 3px; }
  .study-tutor .study-mic, .study-tutor .study-send { width: 45px; height: 45px; flex-basis: 45px; }
  .study-tutor .tutor-call { font-size: 18px; }
}
@media (prefers-reduced-motion: reduce) { .study-design .study-send[aria-busy="true"] { animation: none; } }