:root{--primary:#173e47;--accent:#db8053;--ink:#182c33;--muted:#67767b;--paper:#fffefb;--soft:#f5f7f5;--line:#e5e9e8;--shadow:0 18px 46px rgba(28,59,62,.08)}
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7px}.fraction-show span:last-child{padding-top:7px}.equation{font-size:30px;color:var(--accent);margin:0 2px}.fraction-tiles{display:flex;gap:4px;position:absolute;bottom:23px}.fraction-tiles span{width:42px;height:13px;border-radius:2px;background:#dbe5d7}.fraction-tiles span:nth-child(-n+2){background:#e5a581}.math-card-two{width:263px;left:0;bottom:60px;padding:29px 30px}.math-card-two small{color:var(--accent);font-size:10px;letter-spacing:.15em;font-weight:800}.math-card-two strong{font-family:Georgia,serif;display:block;color:var(--primary);font-size:24px;font-weight:500;line-height:1.25;margin:11px 0 19px}.bar-set{display:flex;gap:5px;align-items:end;height:30px}.bar-set i{display:block;width:19px;height:16px;background:#bacfc8;border-radius:2px}.bar-set i:nth-child(2){height:27px;background:#dca383}.bar-set i:nth-child(3){height:23px}.bar-set i:nth-child(4){height:13px;background:#dca383}.bar-set 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h1{font-size:42px}.admin-heading{display:flex;align-items:center;justify-content:space-between;gap:20px}.admin-body{padding-top:36px}.admin-tiles{display:grid;grid-template-columns:repeat(4,1fr);gap:15px}.action-tile{background:#f3f7f4;padding:19px;border:1px solid var(--line);border-radius:11px;display:flex;flex-direction:column;gap:9px}.action-tile strong{font-size:16px;color:var(--primary)}.action-tile span{font-size:12px;color:var(--muted)}.admin-section{margin-top:42px}.admin-table-wrap{overflow:auto;border:1px solid var(--line);border-radius:10px}.admin-table{border-collapse:collapse;width:100%;min-width:670px;background:#fff;font-size:12px;text-align:left}.admin-table th{background:#f6f8f6;padding:13px;color:var(--primary)}.admin-table td{border-top:1px solid var(--line);padding:12px;vertical-align:middle}.admin-table td>a{font-weight:700}.actions{display:flex;align-items:center;gap:10px}.actions a{font-weight:750}.danger{border:0;background:transparent;color:#ab4b4b;cursor:pointer;font-size:12px;font-weight:700}.danger:hover{color:#6c2222;text-decoration:underline}.editor{border:1px solid var(--line);padding:30px;background:#fff;border-radius:13px;max-width:920px;box-shadow:var(--shadow)}.form-grid{display:grid;grid-template-columns:1fr 1fr;gap:22px}.form-grid>div{min-width:0}.span2{grid-column:span 2}label{display:block;color:var(--primary);font-size:13px;font-weight:700;margin-bottom:7px}input:not([type=checkbox]):not([type=color]),textarea,select{width:100%;border:1px solid #ced8d4;border-radius:7px;background:#fff;padding:10px 12px;color:var(--ink);font-size:14px}textarea{resize:vertical;min-height:100px}input[type=color]{width:85px;height:43px;background:white;border:1px solid #d2dfd9;padding:4px;border-radius:6px}small,.form-note{color:var(--muted);font-size:12px}.check-row{display:flex;align-items:center;gap:9px}.check-row label{margin:0}.editor-footer{display:flex;align-items:center;gap:20px;border-top:1px solid var(--line);margin-top:29px;padding-top:24px}.editor-footer>a{font-size:13px;font-weight:700}.upload-form{max-width:750px}.upload-form input[type=file]{border:2px dashed #bdcfcb;border-radius:11px;padding:40px 20px;background:#f6faf8}.form-note{margin-top:17px}
@media(max-width:1120px){.header-inner{flex-wrap:wrap;gap:8px;padding-top:13px;padding-bottom:15px}.main-nav{justify-content:flex-start}.main-nav>a{font-size:11px}.hero-grid{gap:15px}}@media(max-width:850px){.hero-grid{grid-template-columns:1fr}.hero-copy{padding:70px 0 10px}.hero-art{height:390px;max-width:510px;width:100%;margin:0 auto}.math-card-one{top:10px}.math-card-two{bottom:22px}.topic-grid{grid-template-columns:repeat(2,1fr)}.lesson-grid{grid-template-columns:repeat(2,1fr)}.lesson-layout{grid-template-columns:1fr}.lesson-aside{order:-1}.aside-card{position:static}.admin-tiles{grid-template-columns:repeat(2,1fr)}.footer-inner{grid-template-columns:1fr}.copyright{grid-column:1}.topline-inner span:last-child{display:none}}@media(max-width:580px){.container{padding:0 18px}.brand strong{font-size:18px}.brand-symbol{width:42px;height:42px}.main-nav{gap:9px 14px}.hero h1{font-size:47px}.hero-copy>p{font-size:16px}.hero-art{height:335px}.art-circle-a{height:310px;width:310px}.art-circle-b{width:200px;height:200px}.math-card-one{transform:scale(.79);transform-origin:top right;right:0}.math-card-two{transform:scale(.79);transform-origin:bottom left}.stats div{padding:0 14px}.stats strong{font-size:19px}.topic-grid,.lesson-grid,.feature-grid,.form-grid,.admin-tiles{grid-template-columns:1fr}.span2{grid-column:1}.section{padding-top:48px;padding-bottom:51px}.section-heading{align-items:start;flex-direction:column}.section-heading h2{font-size:30px}.feature-block h2{font-size:27px}.page-hero{padding:38px 0}.page-hero h1{font-size:39px}.worksheet-card{flex-wrap:wrap}.worksheet-card .btn{margin-left:0}.admin-heading{align-items:start;flex-direction:column}.editor{padding:20px}.editor-footer{flex-wrap:wrap}.video-row{padding:13px}.video-row h3{font-size:18px}.video-icon{width:34px;height:34px}}
/* Engineering Studio: all styling below is controlled by saved database fields. */
body{background:var(--body-bg,var(--paper));font-family:var(--body-font,ui-sans-serif,-apple-system,BlinkMacSystemFont,"Segoe UI",sans-serif)}
h1,h2,h3,.hero h1,.page-hero h1,.section-heading h2,.feature-block h2,.topic-title,.footer-brand,.footer-brand,.content-card h3{font-family:var(--heading-font,Georgia,serif)}
.site-header{background:var(--header-bg,#fff)}
.hero{position:relative;isolation:isolate}
.hero.hero-mode-color{background:var(--hero-solid,#f7f7f0)}
.hero.hero-mode-image{background-size:cover;background-position:center}
.hero.hero-mode-youtube{background:var(--hero-solid,#173e47)}
.hero .hero-grid{position:relative;z-index:1;min-height:var(--hero-height,558px)}
.hero .hero-single{grid-template-columns:1fr;max-width:990px}
.hero-copy h1{color:var(--hero-ink,var(--primary))}
.hero-mode-youtube .hero-copy>p,.hero-mode-image .hero-copy>p{color:var(--hero-ink)}
.hero-mode-youtube .stats strong,.hero-mode-image .stats strong,.hero-mode-youtube .stats small,.hero-mode-image .stats small{color:var(--hero-ink)}
.hero-mode-youtube .btn-ghost,.hero-mode-image .btn-ghost{color:var(--hero-ink)}
.hero-video-bg{position:absolute;inset:0;overflow:hidden;pointer-events:none;z-index:-2}
.hero-video-bg iframe{position:absolute;width:max(100%,177.7778vh);height:max(100%,56.25vw);min-width:100%;min-height:100%;top:50%;left:50%;transform:translate(-50%,-50%);border:0;pointer-events:none}
.hero-video-shade{position:absolute;inset:0;background:#0a2127;z-index:-1;pointer-events:none}
.editable-section h2,.editable-section h3{color:var(--section-text,var(--primary))}
.editable-section .section-heading p,.editable-section .free-text{color:var(--section-text,var(--ink))}
.editable-section .topic-grid,.editable-section .lesson-grid,.content-cards{grid-template-columns:repeat(var(--grid-cols,3),minmax(0,1fr))}
.content-cards{display:grid;gap:26px}
.content-card{background:#f2f6f3;border:1px solid rgba(31,55,52,.07);padding:30px;border-radius:14px;min-height:210px;display:flex;flex-direction:column;align-items:flex-start;gap:10px}
.content-card:nth-child(even){background:#f8f1e9}
.content-card img{width:100%;max-height:260px;object-fit:cover;border-radius:9px;margin-bottom:10px}
.content-card h3{font-weight:500;font-size:29px;line-height:1.2;margin:0;color:var(--section-text,var(--primary))}
.content-card p{font-size:15px;color:var(--muted);margin:0 0 12px;white-space:pre-wrap}
.content-card a{margin-top:auto}
.free-text{white-space:pre-wrap;max-width:950px;font-size:17px;line-height:1.9}
.section-image{max-width:100%;max-height:720px;object-fit:contain;border-radius:14px}
.section-video{max-width:1000px;margin:0 auto 23px}
.section-cta{margin-top:25px}
.studio-toolbar{display:grid;grid-template-columns:repeat(2,minmax(0,1fr));gap:14px}
.studio-link{display:flex;flex-direction:column;gap:7px;background:#f1f6f3;border:1px solid #dce8e3;padding:20px 24px;border-radius:12px;min-height:103px}
.studio-link strong{color:var(--primary);font-size:17px}.studio-link span{font-size:12px;color:var(--muted)}
.studio-link:hover{background:#e7f0eb;transform:translateY(-2px)}
.studio-preview-header,.studio-admin-heading{display:flex;justify-content:space-between;align-items:end;gap:20px;margin:45px 0 16px}
.studio-preview-header h2,.studio-admin-heading h2,.studio-form-group h2{font-size:30px;line-height:1.2;margin:7px 0 8px}
.studio-preview-header p,.studio-admin-heading p{color:var(--muted);font-size:14px;margin:0}
.preview-frame{border:1px solid #d6e0db;border-radius:14px;overflow:hidden;background:#fff;box-shadow:0 18px 40px rgba(16,54,54,.08)}
.preview-chrome{display:flex;gap:15px;justify-content:space-between;background:#eaf0eb;color:#55736b;font-size:12px;padding:9px 16px}
.preview-frame iframe{width:100%;height:560px;display:block;border:0;background:white}
.preview-refresh{border:0;background:transparent;color:var(--primary);font-weight:bold;cursor:pointer}
.studio-table-list{border:1px solid var(--line);border-radius:12px;overflow:hidden}
.studio-list-item{display:flex;align-items:center;gap:15px;padding:17px;background:white;border-bottom:1px solid var(--line)}
.studio-list-item:last-child{border:0}
.section-type-icon{width:42px;height:42px;border-radius:8px;display:grid;place-items:center;background:#e8f0ed;color:var(--primary);font-size:22px;flex-shrink:0}
.studio-list-title{display:flex;flex-direction:column;flex:1;min-width:0}
.studio-list-title strong{color:var(--primary);overflow-wrap:anywhere}
.studio-list-title span{color:var(--muted);font-size:12px;overflow-wrap:anywhere}
.studio-item-actions{display:flex;gap:9px;align-items:center;flex-wrap:wrap}
.studio-item-actions a{font-weight:bold;color:var(--primary);font-size:12px}
.studio-item-actions form{margin:0}
.studio-item-actions button{border:1px solid #dbe5e0;padding:5px 9px;border-radius:6px;background:white;cursor:pointer;color:var(--primary);font-size:12px}
.studio-item-actions button.danger{color:#b54c46}
.studio-form-group{border-top:1px solid var(--line);padding-top:26px;margin-top:34px}
.studio-form-group:first-of-type{border:0;padding-top:0;margin-top:0}
.card-editor-item{background:#f7faf8;border:1px solid #dce5e0;padding:20px;border-radius:12px;margin-top:14px}
.card-editor-top{display:flex;justify-content:space-between;margin-bottom:12px}
.card-editor-top strong{font-size:15px;color:var(--primary)}
.security-guide{display:grid;grid-template-columns:1fr 1fr;max-width:920px;gap:15px;margin-bottom:25px}
.security-guide div{padding:21px;background:#eff5f1;border-radius:10px}
.security-guide p{font-size:13px;color:var(--muted);margin:7px 0 0}
@media(max-width:850px){.content-cards,.editable-section .topic-grid,.editable-section .lesson-grid{grid-template-columns:repeat(2,minmax(0,1fr))}.studio-toolbar{grid-template-columns:1fr}.studio-list-item{flex-wrap:wrap}.studio-item-actions{width:100%;margin-left:55px}}
@media(max-width:580px){.content-cards,.editable-section .topic-grid,.editable-section .lesson-grid{grid-template-columns:1fr}.security-guide{grid-template-columns:1fr}.studio-admin-heading,.studio-preview-header{align-items:flex-start;flex-direction:column}.preview-frame iframe{height:390px}.studio-item-actions{margin-left:0}}
@media(prefers-reduced-motion:reduce){.hero-video-bg{display:none}}

.brand-symbol img{max-width:100%;max-height:100%;object-fit:contain}.page-hero{background:linear-gradient(110deg,var(--page-hero-bg,#eef3f0),#fbf7f2)}

/* Unified admin and optional tutor */
.studio-unified{margin-top:35px;border-top:1px solid var(--line);padding-top:12px}
.ai-admin-panel{margin:45px 0 20px;padding:25px;border-radius:16px;background:#eff5f0;border:1px solid #dae8e0}
.ai-admin-grid{display:grid;grid-template-columns:1.2fr 1fr;gap:18px}
.ai-card{background:white;border:1px solid #dbe6e0;padding:20px;border-radius:12px}
.ai-card h3{font-size:21px;margin:0 0 6px}.ai-card label{display:block;font-size:13px;font-weight:700;margin:13px 0 7px}
.ai-card textarea,.ai-card input{width:100%;border:1px solid #b9ccc2;border-radius:9px;padding:12px;background:white;font:inherit}
.ai-card .btn{margin:12px 0}.ai-proposal{border-top:1px solid #ddd;padding-top:14px}
.ai-proposal pre{font-size:12px;white-space:pre-wrap;word-break:break-word;padding:12px;background:#f3f6f4;border-radius:6px;max-height:300px;overflow:auto}
.student-chat{position:fixed;bottom:18px;right:18px;z-index:300;width:min(360px,calc(100vw - 30px));font:inherit}
.student-chat-toggle{display:block;margin-left:auto;background:#183f45;color:white;border:0;border-radius:26px;padding:12px 19px;box-shadow:0 5px 24px #0002;cursor:pointer;font-weight:700}
.student-chat-panel{border:1px solid #c7dcd1;border-radius:14px;margin-bottom:8px;background:white;box-shadow:0 20px 60px #0003;overflow:hidden}
.student-chat-panel[hidden],.ai-proposal[hidden]{display:none}
.student-chat-head{display:flex;align-items:center;justify-content:space-between;background:#173e47;color:white;padding:13px 14px}
.student-chat-head button{background:transparent;color:white;border:0;font-size:24px;cursor:pointer}
.student-note{padding:12px;margin:0;color:#526864;font-size:12px;line-height:1.5}
.student-chat-messages{padding:12px;min-height:115px;max-height:250px;overflow:auto;display:flex;flex-direction:column;gap:10px}
.chat-msg{margin:0;padding:10px 12px;border-radius:10px;font-size:13px;line-height:1.5;white-space:pre-wrap;max-width:95%}
.chat-msg.user{background:#e4f0e9;align-self:end}.chat-msg.assistant{background:#f0f3f1;align-self:start}
.student-chat-form{display:flex;gap:6px;padding:10px;border-top:1px solid #e4ece8}
.student-chat-form textarea{width:100%;border:1px solid #b9ccc2;border-radius:8px;padding:9px;min-width:0;font:inherit;font-size:13px}
.student-chat-form button{white-space:nowrap;align-self:end}
@media(max-width:800px){.ai-admin-grid{grid-template-columns:1fr}.student-chat{bottom:10px;right:10px}}


/* Math in Motion: small lesson video previews (2026-10-28) */
.lesson-card{padding:18px 18px 16px;min-height:300px;overflow:hidden}
.lesson-preview{position:relative;width:100%;aspect-ratio:16/9;margin:13px 0 16px;border-radius:9px;background:#e9f2ef;overflow:hidden;display:grid;place-items:center;isolation:isolate}
.lesson-preview-fallback{position:absolute;inset:0;display:flex;flex-direction:column;align-items:center;justify-content:center;gap:7px;background:linear-gradient(145deg,#e0eee8,#f5f1e8);color:#335a58}
.lesson-preview-math{font-family:Georgia,serif;font-size:clamp(24px,2.4vw,41px);letter-spacing:-.04em;line-height:1.1;color:#668f87;white-space:nowrap}
.lesson-preview-topic{font-size:10px;font-weight:700;letter-spacing:.1em;text-transform:uppercase;color:#76938c}
.lesson-preview-img{position:absolute;inset:0;width:100%;height:100%;object-fit:cover;z-index:1}
.lesson-preview-play{position:absolute;inset:0;z-index:2;display:grid;place-items:center;pointer-events:none}
.lesson-preview-play span{width:44px;height:44px;border-radius:50%;display:grid;place-items:center;background:rgba(15,45,50,.88);color:white;font-size:17px;padding-left:3px;box-shadow:0 4px 16px rgba(0,0,0,.18)}
.lesson-preview-pending{position:absolute;bottom:10px;z-index:2;padding:5px 10px;background:rgba(255,255,255,.85);border-radius:20px;color:#556968;font-weight:600;font-size:11px}
.lesson-card:hover .lesson-preview-img{transform:scale(1.035)}
.lesson-preview-img{transition:transform .24s ease}
.lesson-card h3{font-size:19px;margin:0 0 16px;line-height:1.3}
@media(max-width:580px){.lesson-preview-math{font-size:36px}}
@media(prefers-reduced-motion:reduce){.lesson-preview-img{transition:none}}


/* MATHMOTION_PLAYABLE_LIBRARY_V1: click-to-play lesson cards. */
.lesson-card-playable{display:flex;flex-direction:column;min-height:305px}
.lesson-card-playable .lesson-preview{flex:none;cursor:default}
.lesson-card-playable .lesson-preview-start{position:absolute;inset:0;z-index:3;display:flex;align-items:center;justify-content:center;width:100%;height:100%;border:0;background:transparent;cursor:pointer;color:#fff;padding:0}
.lesson-card-playable .lesson-preview-start .play-symbol{display:grid;place-items:center;width:46px;height:46px;border-radius:50%;font-size:18px;padding-left:3px;background:rgba(14,50,55,.88);box-shadow:0 5px 22px rgba(0,0,0,.22);transition:transform .18s}
.lesson-card-playable .lesson-preview-start:hover .play-symbol,.lesson-card-playable .lesson-preview-start:focus-visible .play-symbol{transform:scale(1.13)}
.lesson-card-playable .lesson-preview-controls{position:absolute;right:7px;top:7px;z-index:7;display:flex;gap:5px}
.lesson-card-playable .lesson-preview-controls button{display:grid;place-items:center;min-width:32px;height:32px;border:1px solid rgba(255,255,255,.35);background:rgba(18,47,51,.85);border-radius:7px;color:white;font-size:20px;cursor:pointer;line-height:1}
.lesson-card-playable .lesson-preview-controls button:hover{background:#173e47}
.lesson-card-playable .lesson-preview-controls button[hidden]{display:none!important}
.lesson-card-playable .lesson-preview.is-playing{background:#081d25}
.lesson-card-playable .lesson-preview.is-playing .lesson-preview-fallback,
.lesson-card-playable .lesson-preview.is-playing .lesson-preview-img,
.lesson-card-playable .lesson-preview.is-playing .lesson-preview-start{display:none}
.lesson-card-playable .lesson-preview iframe{position:absolute;inset:0;width:100%;height:100%;border:0;z-index:4}
.lesson-card-playable h3{margin-top:0}
.lesson-card-playable .lesson-card-title{color:var(--primary)}
.lesson-card-playable .lesson-card-title:hover{color:var(--accent)}
.lesson-card-playable .lesson-card-detail{display:block;margin-top:auto}
.lesson-card-playable .lesson-preview:fullscreen,.lesson-card-playable .lesson-preview:-webkit-full-screen{width:100vw;height:100vh;aspect-ratio:auto;border-radius:0;background:#000;margin:0}
.lesson-card-playable .lesson-preview:fullscreen iframe,.lesson-card-playable .lesson-preview:-webkit-full-screen iframe{width:100%;height:100%}
.lesson-card-playable .lesson-preview:fullscreen .lesson-preview-controls,.lesson-card-playable .lesson-preview:-webkit-full-screen .lesson-preview-controls{right:18px;top:18px}
.visually-hidden{position:absolute!important;width:1px;height:1px;padding:0;margin:-1px;overflow:hidden;clip:rect(0,0,0,0);white-space:nowrap;border:0}
.lesson-poster-edit-grid{display:grid;grid-template-columns:minmax(180px,260px) 1fr;gap:20px;align-items:start}
.lesson-poster-preview{aspect-ratio:16/9;border:1px solid #d0ddd8;border-radius:10px;background:#eff5f2;display:grid;place-items:center;overflow:hidden;color:#66827b;text-align:center;padding:10px}
.lesson-poster-preview img{width:100%;height:100%;object-fit:cover}
.lesson-poster-preview img[hidden],.lesson-poster-preview span[hidden]{display:none}
.lesson-poster-file-label{margin-top:15px}
.library-video-grid{grid-template-columns:repeat(3,minmax(0,1fr));gap:18px}
@media(max-width:900px){.library-video-grid,.lesson-poster-edit-grid{grid-template-columns:repeat(2,minmax(0,1fr))}}
@media(max-width:600px){.library-video-grid,.lesson-poster-edit-grid{grid-template-columns:1fr}}
@media(prefers-reduced-motion:reduce){.lesson-card-playable .lesson-preview-start .play-symbol{transition:none}}

/* MATHMOTION_LAYOUT_V1: prevent navigation wrapping and pin the Admin link at right. */
@media(min-width:1001px){
  .header-inner{display:grid;grid-template-columns:minmax(185px,245px) minmax(0,1fr) auto;gap:14px;align-items:center}
  .main-nav{justify-content:flex-end;flex-wrap:nowrap;gap:clamp(6px,.65vw,11px);min-width:0}
  .main-nav>a{white-space:nowrap;font-size:11px}
  .header-admin{justify-self:end;white-space:nowrap;padding:7px 10px;min-width:58px;text-align:center}
  .brand strong{font-size:20px}
}
@media(min-width:1001px) and (max-width:1230px){
  .header-inner{grid-template-columns:190px minmax(0,1fr) auto;gap:8px}
  .main-nav{overflow-x:auto;justify-content:flex-start;padding-block:12px;scrollbar-width:thin}
  .main-nav>a{font-size:10px;flex-shrink:0}
  .brand small{letter-spacing:.08em;font-size:9px}
  .brand strong{font-size:17px}
}
@media(max-width:1000px){.header-admin{margin-left:auto;white-space:nowrap}.main-nav{order:2;width:100%;justify-content:flex-start;gap:12px}}

/* Hide editor controls on the public website */
.vs-layout-section-handle,
.vs-layout-card-handle {
    display: none;
}

/* MATHMOTION_BILINGUAL_AI_V1: language and admin assistant */
.math-language-switch{display:flex;align-items:center;gap:7px;flex-shrink:0;font-size:12px;color:#73807b;font-weight:800}
.math-language-switch a{padding:4px 6px;border-radius:6px;color:#526864}
.math-language-switch a[aria-current="true"]{background:#e9f1ec;color:#163c43}
.admin-assistant{padding:24px;background:#edf5f1;border:1px solid #d8e6dd;border-radius:15px;margin:30px 0}
.admin-assistant form{display:grid;gap:11px}.admin-assistant textarea,.translation-editor textarea,.translation-picker select{padding:12px;border-radius:9px;border:1px solid #b7c8c0;width:100%;font:inherit}
.admin-assistant-thread{background:#fff;border:1px solid #dfe9e4;border-radius:10px;max-height:300px;min-height:95px;overflow:auto;padding:13px;margin:10px 0}
.agent-chat-line{padding:9px 12px;border-radius:10px;white-space:pre-wrap;max-width:96%;font-size:14px}
.agent-chat-line.user{background:#ebf5ef;margin-left:12%}.agent-chat-line.assistant{background:#f1f2f2;margin-right:12%}
.admin-assistant-proposal{background:#fff;border:1px solid #b1c8bc;padding:15px;border-radius:10px;margin-top:12px}
.admin-assistant-proposal[hidden]{display:none}.admin-assistant-proposal pre{white-space:pre-wrap;overflow:auto;max-height:280px;font-size:12px}
.translation-picker{display:grid;grid-template-columns:150px 1fr;align-items:center;gap:12px;padding:20px;border:1px solid #dce9e1;border-radius:12px;margin:22px 0}
.translation-editor{display:grid;gap:22px}.translation-pair{display:grid;grid-template-columns:1fr 1fr;gap:14px}
.translation-pair label,.translation-picker label{font-weight:bold;font-size:13px;display:block;margin-bottom:5px}
.translation-original{background:#f1f5f2;border-radius:8px;padding:14px;white-space:pre-wrap;max-height:300px;overflow:auto}
@media(max-width:850px){.translation-pair,.translation-picker{grid-template-columns:1fr}.math-language-switch{margin-left:auto}}

/* MATHMOTION_VIDEO_HOVER_V1: Accessible lesson dropdowns, separate from editor controls. */
.math-video-menu-trigger{white-space:nowrap}
.math-menu-chevron{margin-left:4px;font-size:14px;opacity:.7}
.math-video-dropdown{display:none;position:fixed;left:0;top:0;width:min(400px,calc(100vw - 24px));max-height:min(72vh,600px);overflow-y:auto;overscroll-behavior:contain;z-index:1000;background:#fff;border:1px solid #dce7e1;border-radius:13px;box-shadow:0 18px 45px rgba(18,45,42,.19);padding:10px 0;text-align:left}
.math-video-dropdown.is-open{display:block}
.math-video-dropdown-heading{padding:8px 17px 10px;font-size:13px;font-weight:800;color:#173e47;border-bottom:1px solid #edf0ed}
.math-video-dropdown-topic{font-size:11px;text-transform:uppercase;letter-spacing:.07em;font-weight:800;color:#467268;background:#f3f8f5;padding:7px 17px;margin-top:8px}
.math-video-dropdown-lesson,.math-video-dropdown-all{display:block;padding:7px 17px;font-size:13px;font-weight:600;line-height:1.4;color:#2e494e;white-space:normal}
.math-video-dropdown-lesson:hover,.math-video-dropdown-lesson:focus-visible,.math-video-dropdown-all:hover,.math-video-dropdown-all:focus-visible{background:#eaf3ef;color:#153f43}
.math-video-dropdown-all{border-top:1px solid #edf0ed;margin-top:8px;color:#1a6158;font-weight:800}
.math-video-dropdown-empty{font-size:13px;padding:12px 17px;color:#657977}
.vis-is-editing .math-video-dropdown{display:none!important}
@media(max-width:650px){.math-video-dropdown{max-height:65vh}.math-video-dropdown-lesson{padding:10px 17px}}
@media(prefers-reduced-motion:reduce){.math-video-dropdown{scroll-behavior:auto}}