/* Design tokens: see docs/style-guide.md. Change values here, not in the rules below.
   Calm, warm, trustworthy: cream and sand surfaces, a deep sage accent, soft shadows. */
:root {
  --font-body: ui-rounded, "SF Pro Rounded", "Nunito", system-ui, -apple-system, "Segoe UI", sans-serif;
  --font-display: "Iowan Old Style", "Palatino Linotype", Palatino, "Book Antiqua", Georgia, serif;
  --font-mono: ui-monospace, SFMono-Regular, Menlo, monospace;
  --text-sm: 13px; --text-md: 16px; --text-lg: 18px; --text-xl: 22px; --text-display: 30px;
  --space-1: 4px; --space-2: 8px; --space-3: 12px; --space-4: 16px; --space-5: 24px; --space-6: 32px; --space-7: 48px;
  --radius-1: 8px; --radius-2: 14px; --radius-3: 20px; --radius-pill: 999px;
  --shadow-1: 0 1px 2px rgba(74, 56, 30, .05), 0 6px 20px rgba(74, 56, 30, .06);
  --shadow-2: 0 2px 4px rgba(74, 56, 30, .06), 0 14px 34px rgba(74, 56, 30, .10);
  --color-bg: #faf6f0; --color-surface: #fffdf9; --color-surface-2: #f3ece2; --color-text: #2b2a27;
  --color-muted: #6e6a62; --color-line: #e8dfd2; --color-accent: #2f6e62; --color-accent-text: #ffffff;
  --color-accent-soft: #e3efea; --color-focus: #2f6e62;
  --color-student: #e3efea; --color-student-text: #1f3d36; --color-assistant: #fffdf9;
  --color-success: #2f7a52; --color-warning: #9a5b12; --color-danger: #b0402f;
  --color-banner: transparent; --color-banner-line: transparent;
  --mode-assignment: #e3efea; --mode-remediation: #fbe9d3; --mode-deepening: #e5e9f6; --mode-broadening: #f1e4f0;
  --mode-exam_preparation: #f8e2da; --mode-discovery: #eef0dc;
  --badge-template: #7a7468; --badge-model: #2f6e62; --badge-fallback: #9a5b12; --badge-safety: #b0402f;
}
@media (prefers-color-scheme: dark) {
  :root {
    --color-bg: #1b1916; --color-surface: #23201c; --color-surface-2: #2d2924; --color-text: #eee8de;
    --color-muted: #a8a094; --color-line: #3a352e; --color-accent: #7fbfae; --color-accent-text: #14211d;
    --color-accent-soft: #24332f; --color-focus: #9fd3c4;
    --color-student: #2a3b36; --color-student-text: #e6f2ee; --color-assistant: #23201c;
    --mode-assignment: #24332f; --mode-remediation: #3a2d1d; --mode-deepening: #262b3a; --mode-broadening: #352734;
    --mode-exam_preparation: #3a2520; --mode-discovery: #2f3122;
    --shadow-1: none; --shadow-2: 0 10px 30px rgba(0, 0, 0, .35);
  }
}

* { box-sizing: border-box; }
html { background: var(--color-bg); }
body { margin: 0; height: 100dvh; overflow: hidden; display: flex; flex-direction: column; font: var(--text-md)/1.55 var(--font-body);
       background: var(--color-bg); color: var(--color-text); -webkit-font-smoothing: antialiased; }
select, input, button, textarea { font: inherit; color: inherit; }
:focus-visible { outline: 2px solid var(--color-focus); outline-offset: 2px; }
.visually-hidden { position: absolute; width: 1px; height: 1px; overflow: hidden; clip: rect(0 0 0 0); white-space: nowrap; }
.muted { color: var(--color-muted); }
.display { font-family: var(--font-display); font-weight: 600; letter-spacing: -.005em; }
code { font: 12px/1.4 var(--font-mono); background: var(--color-surface-2); padding: 0 3px; border-radius: 3px; }
[hidden] { display: none !important; }

/* Views: student (calm), teacher and school (test and adjust), reviewer (traces). */
body[data-view="student"] .only-staff, body[data-view="student"] .only-reviewer, body[data-view="student"] .only-teacher,
body[data-view="teacher"] .only-reviewer, body[data-view="reviewer"] .only-teacher,
body:not([data-view="school"]) .only-school, body[data-view="school"] .only-teacher,
body[data-view="school"] .only-reviewer { display: none !important; }

/* Top bar */
.topbar { display: flex; flex-wrap: wrap; align-items: center; justify-content: space-between; gap: var(--space-3);
          padding: var(--space-4) var(--space-6); }
.brand { display: flex; align-items: center; gap: var(--space-2); }
.logo { width: 30px; height: 30px; border-radius: 10px; background: var(--color-accent);
        box-shadow: inset -6px -6px 0 rgba(255, 255, 255, .18); }
h1 { font: 600 var(--text-xl)/1.2 var(--font-display); margin: 0; }
.tag { font-size: 11px; font-weight: 700; text-transform: uppercase; letter-spacing: .08em; color: var(--color-muted);
       background: var(--color-surface-2); border-radius: var(--radius-pill); padding: 2px 9px; }
.topbar-right { display: flex; align-items: center; gap: var(--space-4); }
.identity { font-size: var(--text-sm); color: var(--color-muted); }
.online-toggle { display: inline-flex; align-items: center; gap: 7px; padding: 5px 12px; font-size: var(--text-sm);
                 background: var(--color-surface-2); border-color: transparent; color: var(--color-muted); }
.online-toggle .dot { width: 8px; height: 8px; border-radius: 50%; background: var(--color-muted); }
.online-toggle.on { color: var(--color-accent); background: var(--color-accent-soft); font-weight: 600; }
.online-toggle.on .dot { background: var(--color-success); box-shadow: 0 0 0 3px rgba(47, 122, 82, .18); }
.view-switch { display: inline-flex; border: 0; border-radius: var(--radius-pill); padding: 3px; margin: 0; background: var(--color-surface-2); }
.view-switch label { cursor: pointer; }
.view-switch input { position: absolute; opacity: 0; pointer-events: none; }
.view-switch span { display: inline-block; padding: 5px 14px; border-radius: var(--radius-pill); font-size: var(--text-sm); color: var(--color-muted); }
.view-switch input:checked + span { background: var(--color-surface); color: var(--color-text); font-weight: 600; box-shadow: var(--shadow-1); }
.view-switch input:focus-visible + span { outline: 2px solid var(--color-focus); }

/* Demo bar (teacher and reviewer only) */
.demo-bar { display: flex; flex-wrap: wrap; align-items: end; gap: var(--space-3) var(--space-4); margin: 0 var(--space-6);
            padding: var(--space-3) var(--space-4); background: var(--color-surface-2); border-radius: var(--radius-2); }
.demo-bar-title { font-size: 12px; font-weight: 700; text-transform: uppercase; letter-spacing: .06em; color: var(--color-muted); align-self: center; }
.demo-bar label, .subject-pick { display: flex; flex-direction: column; font-size: 12px; color: var(--color-muted); gap: 3px; }
.note { font-size: 12px; color: var(--color-muted); align-self: center; }

select { padding: 7px 34px 7px 12px; border: 1px solid var(--color-line); border-radius: var(--radius-1); background-color: var(--color-surface);
         appearance: none; background-image: linear-gradient(45deg, transparent 50%, currentColor 50%), linear-gradient(135deg, currentColor 50%, transparent 50%);
         background-position: calc(100% - 16px) 52%, calc(100% - 11px) 52%; background-size: 5px 5px; background-repeat: no-repeat; }
button { padding: 8px 16px; border: 1px solid var(--color-line); border-radius: var(--radius-pill); background: var(--color-surface); cursor: pointer;
         transition: background .15s ease, border-color .15s ease; }
button:hover { background: var(--color-surface-2); }
button.primary { background: var(--color-accent); color: var(--color-accent-text); border-color: var(--color-accent); font-weight: 600; }
button.primary:hover { filter: brightness(1.06); }
button.ghost { border-color: transparent; background: transparent; color: var(--color-muted); padding: 4px 8px; font-size: 13px; }
button.ghost:hover, button.ghost:focus-visible { background: var(--color-surface-2); color: var(--color-text); }
button.secondary { border-color: var(--color-accent); color: var(--color-accent); font-weight: 600; }
button.secondary:hover { background: var(--color-accent-soft); }
button.small { padding: 4px 12px; font-size: 13px; }
button.icon-button { display: inline-flex; align-items: center; justify-content: center; padding: var(--space-2); }
button.icon-button:hover { color: var(--color-text); }
button.link { border: 0; background: none; padding: 0; color: var(--color-accent); font-weight: 600; }
button:disabled, input:disabled, select:disabled { opacity: .5; cursor: not-allowed; }
.error { color: var(--color-danger); margin: var(--space-3) var(--space-6) 0; }

/* Home: what do you want to work on today? */
.home { flex: 1; min-height: 0; overflow-y: auto; padding: var(--space-6) max(var(--space-5), calc((100% - 980px) / 2)) var(--space-7); }
.home-head { display: flex; flex-wrap: wrap; align-items: end; justify-content: space-between; gap: var(--space-4); margin-bottom: var(--space-5); }
.home-head .display { font-size: var(--text-display); margin: 0; line-height: 1.15; }
.pick-label { font-size: 12px; color: var(--color-muted); }
.dropdown { position: relative; }
.dropdown-button { display: inline-flex; align-items: center; gap: var(--space-3); min-width: 240px; padding: 10px 16px;
                   border-radius: var(--radius-2); background: var(--color-surface); border: 1px solid var(--color-line);
                   box-shadow: var(--shadow-1); font-size: var(--text-md); text-align: left; }
.dropdown-button:hover { background: var(--color-surface); border-color: var(--color-accent); }
.dropdown-value { font-weight: 600; flex: 1; }
.dropdown-note { font-size: 12px; color: var(--color-muted); }
.chevron { width: 8px; height: 8px; border-right: 2px solid var(--color-muted); border-bottom: 2px solid var(--color-muted);
           transform: rotate(45deg) translateY(-2px); transition: transform .15s ease; }
.dropdown-button[aria-expanded="true"] .chevron { transform: rotate(-135deg) translateY(-2px); }
.dropdown-list { position: absolute; right: 0; top: calc(100% + 6px); z-index: 10; min-width: 100%; margin: 0; padding: var(--space-1);
                 list-style: none; background: var(--color-surface); border: 1px solid var(--color-line); border-radius: var(--radius-2);
                 box-shadow: var(--shadow-2); max-height: 320px; overflow-y: auto; }
.dropdown-list:focus { outline: none; }
.dropdown-option { display: flex; justify-content: space-between; gap: var(--space-4); padding: 9px 12px; border-radius: var(--radius-1);
                   cursor: pointer; }
.dropdown-option.active { background: var(--color-surface-2); }
.dropdown-option[aria-selected="true"] { font-weight: 600; color: var(--color-accent); }
.env-group { margin-top: var(--space-5); }
.env-group h3 { font-size: var(--text-sm); font-weight: 700; text-transform: uppercase; letter-spacing: .07em; color: var(--color-muted);
                margin: 0 0 var(--space-3); }
.cards { display: grid; grid-template-columns: repeat(auto-fill, minmax(260px, 1fr)); gap: var(--space-4); }
.card { display: flex; flex-direction: column; align-items: flex-start; gap: var(--space-2); text-align: left; padding: var(--space-5);
        border: 1px solid var(--color-line); border-radius: var(--radius-3); background: var(--color-surface); box-shadow: var(--shadow-1);
        transition: transform .15s ease, box-shadow .15s ease; min-height: 150px; }
.card:hover { transform: translateY(-2px); box-shadow: var(--shadow-2); background: var(--color-surface); }
.card-title { font: 600 var(--text-lg)/1.3 var(--font-display); }
.card-desc { font-size: var(--text-sm); color: var(--color-muted); }
.card-foot { margin-top: auto; font-size: 12px; color: var(--color-muted); }
.mode-pill::first-letter, .who::first-letter { text-transform: uppercase; }
.teacher-panel .hint { text-align: left; }
.mode-pill { display: inline-block; font-size: 12px; font-weight: 600; border-radius: var(--radius-pill); padding: 2px 10px; background: var(--mode-assignment); }
.mode-pill.remediation { background: var(--mode-remediation); } .mode-pill.deepening { background: var(--mode-deepening); }
.mode-pill.broadening { background: var(--mode-broadening); } .mode-pill.exam_preparation { background: var(--mode-exam_preparation); }
.mode-pill.discovery { background: var(--mode-discovery); }
@media (prefers-reduced-motion: reduce) { .card, .card:hover { transition: none; transform: none; } }

/* Conversation */
.layout { display: grid; grid-template-columns: minmax(0, 3fr) minmax(0, 2fr); grid-template-rows: minmax(0, 1fr);
          gap: var(--space-5); width: 100%; padding: var(--space-4) var(--space-6); flex: 1; min-height: 0; }
body[data-view="student"] .layout { grid-template-columns: minmax(0, 820px); justify-content: center; }
.chat, .why, .teacher-panel { background: var(--color-surface); border: 1px solid var(--color-line); border-radius: var(--radius-3);
                              padding: var(--space-5); box-shadow: var(--shadow-1); min-height: 0; min-width: 0; }
.chat { display: flex; flex-direction: column; }
.why, .teacher-panel { overflow-y: auto; }
.chat-head { display: grid; grid-template-columns: 1fr auto; gap: var(--space-2) var(--space-3); align-items: start;
             padding-bottom: var(--space-2); border-bottom: 1px solid var(--color-line); }
.chat-head #back { grid-column: 1 / -1; justify-self: start; font-size: var(--text-sm); }
.chat-title { display: flex; flex-wrap: wrap; align-items: center; gap: var(--space-1) var(--space-2); min-width: 0; }
.chat-title .display { font-size: var(--text-xl); margin: 0; }
.title-toggle { all: unset; cursor: pointer; display: inline-flex; align-items: center; gap: var(--space-2); border-radius: var(--radius-1); }
.title-toggle:focus-visible { outline: 2px solid var(--color-accent); outline-offset: 2px; }
.title-toggle .chevron { width: 8px; height: 8px; border-right: 2px solid var(--color-muted); border-bottom: 2px solid var(--color-muted);
                         transform: translateY(-3px) rotate(45deg); transition: transform .15s; }
.title-toggle[aria-expanded="true"] .chevron { transform: translateY(1px) rotate(-135deg); }
.title-toggle:hover .chevron { border-color: var(--color-text); }
.chat-meta { flex-basis: 100%; }
.who { margin: 0; color: var(--color-muted); font-size: var(--text-sm); }
.model-chip { margin: var(--space-1) 0 0; color: var(--color-muted); font-size: var(--text-sm); }
.draft-pill { color: var(--color-warning); }
.summary { display: flex; flex-wrap: wrap; gap: var(--space-1) var(--space-4); margin: var(--space-2) 0 0; font-size: 12px; }
.summary div { display: flex; gap: var(--space-1); }
.summary dt { color: var(--color-muted); }
.summary dd { margin: 0; font-weight: 600; }

.messages { display: flex; flex-direction: column; gap: var(--space-4); flex: 1; min-height: 0; overflow-y: auto;
            padding: var(--space-5) var(--space-1); scrollbar-gutter: stable; }
.empty { margin: auto; text-align: center; max-width: 420px; color: var(--color-muted); }
.empty .display { color: var(--color-text); font-size: var(--text-xl); margin: 0 0 var(--space-2); }
.bubble { max-width: 82%; padding: var(--space-3) var(--space-4); border-radius: var(--radius-3); white-space: pre-wrap; }
.bubble.student { align-self: flex-end; background: var(--color-student); color: var(--color-student-text); border-bottom-right-radius: 6px; }
.bubble.assistant { align-self: flex-start; background: var(--color-assistant); border: 1px solid var(--color-line); border-bottom-left-radius: 6px; }
body[data-view="reviewer"] .bubble.assistant { cursor: pointer; }
.bubble.assistant.selected { outline: 2px solid var(--color-accent); }
.badge { display: inline-block; font-size: 11px; font-weight: 700; letter-spacing: .02em; padding: 1px 7px;
         border-radius: 5px; color: #fff; margin-bottom: var(--space-1); white-space: normal; }
.badge.template { background: var(--badge-template); }
.badge.model { background: var(--badge-model); }
.badge.template_fallback { background: var(--badge-fallback); }
.badge.template_safety { background: var(--badge-safety); }
.badge.ai { background: transparent; color: var(--color-accent); padding: 0; }
.badge.knowledge { margin-left: var(--space-2); background: var(--color-accent-soft); color: var(--color-accent); }

.chat-head, .samples, .symbols, .composer, .hint { flex-shrink: 0; }
.samples { display: flex; flex-wrap: nowrap; gap: var(--space-2); justify-content: safe center; margin: var(--space-3) 0 0;
           overflow-x: auto; padding-bottom: var(--space-1); scrollbar-width: thin; }
.samples button { flex: 0 0 auto; font-size: var(--text-sm); padding: 6px 14px; background: var(--color-surface-2); border-color: transparent;
                  white-space: nowrap; }
.samples button:hover { background: var(--color-accent-soft); }
.samples .more-ideas { background: transparent; border: 1px dashed var(--color-line); color: var(--color-muted); }
body:not([data-view="student"]) .samples { justify-content: flex-start; }
.composer { display: flex; gap: var(--space-2); align-items: flex-end; padding: var(--space-2); margin-top: var(--space-2);
            background: var(--color-surface-2); border-radius: var(--radius-3); }
.composer textarea { flex: 1; padding: var(--space-2) var(--space-3); border: 0; background: transparent; resize: none; overflow-y: auto;
                     line-height: 1.5; max-height: 180px; }
.composer textarea:focus-visible { outline: none; }
.composer:focus-within { box-shadow: 0 0 0 2px var(--color-focus); }
.symbols { display: flex; flex-wrap: wrap; gap: var(--space-1); margin-top: var(--space-2); }
.symbols button { min-width: 34px; padding: 4px 8px; font-size: var(--text-sm); background: var(--color-surface-2); border-color: transparent; }
.symbols button:hover { background: var(--color-accent-soft); }
.hint { margin: var(--space-2) 0 0; font-size: 12px; color: var(--color-muted); text-align: center; }

.student-turn { align-self: flex-end; display: flex; flex-direction: column; align-items: flex-end; gap: 2px; max-width: 82%; }
.student-turn .bubble { max-width: 100%; }
.spelling { font-size: var(--text-sm); color: var(--color-muted); padding-right: var(--space-2); }
.spelling strong { color: var(--color-text); }
.spelling.fixed { color: var(--color-accent); }
.misspelt { text-decoration: underline wavy; text-decoration-thickness: 1.5px; text-underline-offset: 3px; }
.reply { display: flex; flex-direction: column; align-items: flex-start; gap: 2px; }
.reply .bubble { max-width: 82%; }
.feedback { display: flex; flex-wrap: wrap; align-items: center; gap: var(--space-1); font-size: var(--text-sm); padding-left: var(--space-2); }
.thumb { padding: 0 6px; border-color: transparent; background: transparent; font-size: 14px; opacity: .5; filter: grayscale(1); }
.thumb:hover { opacity: .9; background: var(--color-surface-2); }
.thumb[aria-pressed="true"] { opacity: 1; filter: none; background: var(--color-accent-soft); }
.reasons { display: flex; flex-wrap: wrap; align-items: center; gap: var(--space-1); width: 100%; margin-top: 2px; }
.chip { font-size: 12px; padding: 2px 11px; }
.chip[aria-pressed="true"] { background: var(--color-accent-soft); border-color: var(--color-accent); }
.thanks { margin-left: var(--space-1); }
.bubble.thinking { display: flex; align-items: center; gap: var(--space-2); color: var(--color-muted); cursor: default; }
.dots { display: inline-flex; gap: 4px; }
.dots span { width: 7px; height: 7px; border-radius: 50%; background: var(--color-accent); animation: pulse 1.3s infinite ease-in-out; }
.dots span:nth-child(2) { animation-delay: .2s; }
.notice.waiting { display: flex; align-items: center; gap: var(--space-2); }
button .dots { margin-left: var(--space-2); vertical-align: middle; }
button .dots span { width: 5px; height: 5px; }
.dots span:nth-child(3) { animation-delay: .4s; }
@keyframes pulse { 0%, 80%, 100% { opacity: .25; transform: scale(.8); } 40% { opacity: 1; transform: scale(1); } }
@media (prefers-reduced-motion: reduce) { .dots span { animation: none; opacity: .6; } }

/* Rich text: formatted in the browser (format.js), never by a model */
.rich p { margin: 0 0 var(--space-2); }
.rich p:last-child { margin-bottom: 0; }
.rich ul { margin: var(--space-1) 0 var(--space-2); padding-left: 20px; }
.rich li { margin: 2px 0; }
.rich a, .sources a { color: var(--color-accent); text-decoration-thickness: 1px; text-underline-offset: 2px; word-break: break-word; }
.formula { display: inline; padding: 1px .35em; margin: 0 .05em; box-decoration-break: clone; -webkit-box-decoration-break: clone;
           border-radius: 6px; background: var(--color-accent-soft); font-family: var(--font-display); font-size: 1.04em;
           white-space: nowrap; }
.bubble.student .formula { background: rgba(255, 255, 255, .45); }
.f-var { font-style: italic; }
.f-num { font-variant-numeric: tabular-nums; }
.f-unit { font-style: normal; }
.f-op { color: var(--color-muted); }
.cite { display: inline-block; font: 600 10px/1.6 var(--font-body); color: var(--color-accent); background: var(--color-accent-soft);
        border-radius: var(--radius-pill); padding: 0 6px; margin-left: 2px; vertical-align: super; }
.knowledge { display: inline-block; font-size: 11px; font-weight: 700; letter-spacing: .02em; color: var(--color-warning);
             background: var(--mode-remediation); border-radius: var(--radius-pill); padding: 0 8px; margin-right: 4px; }
.sources { margin-top: var(--space-3); padding-top: var(--space-2); border-top: 1px dashed var(--color-line); font-size: var(--text-sm); }
.sources-title { display: block; font-size: 11px; font-weight: 700; text-transform: uppercase; letter-spacing: .06em;
                 color: var(--color-muted); margin-bottom: 2px; }
.sources ul { list-style: none; margin: 0; padding: 0; }
.sources li { display: flex; flex-wrap: wrap; align-items: baseline; gap: 2px var(--space-2); padding: 2px 0; }
.sources .cite { vertical-align: baseline; margin: 0; }

.actions { display: flex; flex-wrap: wrap; gap: var(--space-2); margin: var(--space-2) 0 var(--space-1); }
.action { font-size: var(--text-sm); padding: 6px 14px; background: var(--color-surface); border-color: var(--color-line); }
.action:hover { border-color: var(--color-accent); background: var(--color-accent-soft); }
.action.search-link { display: inline-block; text-decoration: none; color: var(--color-accent); border: 1px solid var(--color-line); border-radius: var(--radius-pill); }
.action.primary-soft { background: var(--color-accent-soft); border-color: transparent; color: var(--color-accent); font-weight: 600; }

/* Side panels */
.why h2, .teacher-panel h2 { font: 600 var(--text-lg)/1.3 var(--font-display); margin: 0 0 var(--space-2); }
.why h3, .teacher-panel h3 { font-size: 12px; margin: var(--space-4) 0 var(--space-1); color: var(--color-muted);
                             text-transform: uppercase; letter-spacing: .06em; }
.why ul { margin: 0; padding-left: 18px; }
.why li { margin: 2px 0; }

.field { padding: var(--space-3) 0; border-top: 1px solid var(--color-line); }
.field-head { display: flex; justify-content: space-between; gap: var(--space-2); align-items: baseline; }
.field-name { font-weight: 600; }
.field-path { font-size: 11px; color: var(--color-muted); }
.field-value { margin-top: 2px; }
.value-list { margin: 2px 0 0; padding-left: 18px; }
.value-list li + li { margin-top: 2px; }
.value-list .value-title { font-weight: 500; }
.value-list li::first-letter { text-transform: uppercase; }
.field-meta { display: flex; flex-wrap: wrap; gap: var(--space-1); margin-top: var(--space-1); }
.pill { font-size: 11px; border-radius: var(--radius-pill); padding: 1px 9px; background: var(--color-surface-2); color: var(--color-muted); }
.pill.lock { color: var(--color-warning); }
.pill.note { color: var(--color-danger); }
.draft-actions { display: flex; flex-wrap: wrap; gap: var(--space-2); margin: var(--space-3) 0; }
.ask { margin: var(--space-3) 0; padding: var(--space-3); border: 1px solid var(--color-line); border-radius: var(--radius-2); }
.ask-input { width: 100%; box-sizing: border-box; margin-top: var(--space-1); resize: vertical; font: inherit; }
.ask-actions { display: flex; flex-wrap: wrap; align-items: center; gap: var(--space-2); margin-top: var(--space-2); }
.card-new { border-style: dashed; align-items: center; justify-content: center; text-align: center; }
.card-plus { font-size: 28px; line-height: 1; color: var(--color-accent); }
.card.custom { border-color: var(--color-accent); }
.form-card { padding: var(--space-4); border: 1px solid var(--color-line); border-radius: var(--radius-2); background: var(--color-surface); }
.form-card h3 { margin-top: 0; }
.form-row { display: flex; flex-direction: column; gap: 2px; margin-top: var(--space-2); }
.suggestion { padding: var(--space-2) 0; border-top: 1px solid var(--color-line); }
.suggestion p { margin: 0 0 var(--space-1); }
.ask-actions .hint { flex: 1 1 200px; min-width: 0; margin: 0; }
.proposal { margin-top: var(--space-2); }
.proposal-list { margin: var(--space-1) 0 0; padding-left: 18px; font-size: var(--text-sm); }
.proposal-list li { margin-bottom: var(--space-1); }
.draft-results { margin: 0 0 var(--space-2); padding-left: 18px; font-size: var(--text-sm); }
.outcome-applied, .outcome-removed { color: var(--color-success); }
.outcome-capped, .outcome-locked { color: var(--color-warning); }
.outcome-refused { color: var(--color-danger); }
.field-input { margin-top: var(--space-1); max-width: 100%; }
.help-toggle { width: 18px; height: 18px; padding: 0; border-radius: 50%; font-size: 11px; line-height: 16px; vertical-align: 1px;
               color: var(--color-muted); background: transparent; border: 1px solid var(--color-line); }
.help-toggle[aria-expanded="true"] { color: var(--color-accent); border-color: var(--color-accent); background: var(--color-accent-soft); }
.field-help { margin: var(--space-1) 0 var(--space-2); padding: var(--space-2) var(--space-3); font-size: var(--text-sm);
              background: var(--color-surface-2); border-radius: var(--radius-1); }
.slider { display: flex; align-items: center; gap: var(--space-2); margin-top: var(--space-1); flex-wrap: wrap; }
.slider input[type="range"] { flex: 1 1 140px; margin: 0; accent-color: var(--color-accent); }
.slider-end { font-size: 11px; color: var(--color-muted); }
.slider-foot { flex-basis: 100%; display: flex; align-items: center; gap: var(--space-1); }
.slider-value { font-size: var(--text-sm); font-weight: 600; }
.segmented { display: inline-flex; flex-wrap: wrap; gap: 2px; margin-top: var(--space-1); padding: 2px;
             background: var(--color-surface-2); border-radius: var(--radius-1); max-width: 100%; }
.segmented button { border: 0; background: transparent; padding: 4px 10px; font-size: var(--text-sm); border-radius: 6px; color: var(--color-muted); }
.inherit-reset { border: 0; background: transparent; color: var(--color-muted); padding: 2px 6px; font-size: var(--text-sm); }
.inherit-reset:hover { color: var(--color-text); }
.segmented button[aria-pressed="true"] { background: var(--color-surface); color: var(--color-text); box-shadow: var(--shadow-1); font-weight: 600; }
.multi { display: flex; flex-wrap: wrap; gap: var(--space-1) var(--space-3); margin-top: var(--space-1); font-size: var(--text-sm); }
.teacher-panel input[type="text"], .teacher-panel input[type="number"] { padding: 6px 10px; border: 1px solid var(--color-line);
  border-radius: var(--radius-1); background: var(--color-surface); width: 100%; }
.teacher-panel .group { border: 1px solid var(--color-line); border-radius: var(--radius-2); padding: var(--space-2) var(--space-3);
                        margin-top: var(--space-3); background: var(--color-surface); }
.teacher-panel .group > summary { display: flex; flex-direction: column; gap: 2px; list-style: none; cursor: pointer; margin: 0; }
.teacher-panel .group > summary::-webkit-details-marker { display: none; }
.teacher-panel .group > summary .group-title { font-weight: 600; color: var(--color-text); }
.teacher-panel .group > summary .group-title::before { content: "▸ "; color: var(--color-muted); }
.teacher-panel .group[open] > summary .group-title::before { content: "▾ "; }
.teacher-panel .group > summary .group-summary { font-size: 12px; color: var(--color-muted); }
.teacher-panel .group-more { margin-top: var(--space-2); }
.chips { display: flex; flex-wrap: wrap; gap: 6px; align-items: center; }
.chip { display: inline-flex; align-items: center; gap: 4px; padding: 2px 10px 2px 10px; border-radius: var(--radius-pill);
        background: var(--color-surface-2); border: 1px solid var(--color-line); font-size: 13px; }
.chip-x { border: 0; background: transparent; cursor: pointer; font-size: 15px; line-height: 1; padding: 2px 6px;
          border-radius: var(--radius-pill); color: var(--color-muted); }
.chip-x:hover, .chip-x:focus-visible { background: var(--color-line); color: var(--color-text); }
.teacher-panel .chip-add { min-width: 12em; flex: 1 1 12em; padding: 4px 10px; border: 1px solid var(--color-line);
                           border-radius: var(--radius-pill); font: inherit; font-size: 13px; background: var(--color-surface); }
.chip-button { padding: 4px 12px; font-size: 13px; }
.chip-error { flex-basis: 100%; font-size: 12px; color: var(--color-danger); }
.chip-error:empty { display: none; }
.chip-hint { flex-basis: 100%; font-size: 12px; color: var(--color-muted); }
.teacher-panel .preset { display: flex; flex-wrap: wrap; align-items: center; gap: var(--space-2); margin: var(--space-2) 0; }
.teacher-panel .preset-label { font-weight: 600; font-size: 13px; }
.teacher-panel .preset-about { flex-basis: 100%; margin: 0; }
.teacher-panel .preset-about:empty { display: none; }
.pill.changed { border: 1px solid var(--color-warning); color: var(--color-warning); }
.teacher-panel .field-why { margin: var(--space-1) 0 0; font-size: 12px; color: var(--color-muted); }
.teacher-panel details summary { cursor: pointer; color: var(--color-muted); margin-top: var(--space-4); }

.footer { padding: var(--space-1) var(--space-6) var(--space-3); }
.banner { margin: 0 auto; max-width: 820px; text-align: center; font-size: 12px; color: var(--color-muted);
          background: var(--color-banner); border: 1px solid var(--color-banner-line); }

@media (max-width: 900px) {
  body { height: auto; min-height: 100dvh; overflow: auto; }
  .home { overflow: visible; }
  .layout { grid-template-columns: 1fr; grid-template-rows: none; padding: var(--space-4); }
  .messages { max-height: 55vh; }
  body[data-view="student"] .layout { grid-template-columns: minmax(0, 1fr); }
  .chat, .why, .teacher-panel { padding: var(--space-4); }
  .chat-title .display { font-size: var(--text-lg); }
  .topbar { gap: var(--space-2); }
  .topbar-right { width: 100%; justify-content: space-between; }
  .topbar, .footer { padding-left: var(--space-4); padding-right: var(--space-4); }
  .demo-bar { margin: 0 var(--space-4); }
  .home { padding: var(--space-5) var(--space-4); }
  .home-head .display { font-size: 24px; }
}

/* Phones: identity on its own line, then the online toggle, then the view switch at full width. */
@media (max-width: 560px) {
  .topbar-right { flex-wrap: wrap; gap: var(--space-2) var(--space-3); }
  .identity { flex: 1 0 100%; }
  .view-switch { display: flex; flex: 1 0 100%; }
  .view-switch label { flex: 1; }
  .view-switch span { display: block; text-align: center; padding: 6px 8px; }
}

/* New learning environment in steps and the teacher's resources (D63-D66) */
.form-card .step { margin-top: var(--space-4); padding-top: var(--space-3); border-top: 1px solid var(--color-line); }
.form-card h4 { margin: 0 0 var(--space-2); font-size: 14px; }
.choice { display: flex; gap: var(--space-2); align-items: flex-start; padding: var(--space-1) 0; cursor: pointer; }
.choice input { margin-top: 3px; flex: none; }
.choice input:disabled + .choice-text { opacity: 0.6; }
.choice-text { display: flex; flex-direction: column; min-width: 0; overflow-wrap: anywhere; }
.choice-note { font-size: 12px; }
.notice { margin: var(--space-2) 0; padding: var(--space-2) var(--space-3); border-radius: var(--radius-1);
  background: var(--color-surface-2); font-size: 13px; }
.notice.warn { border-left: 3px solid var(--color-warning); }
.notice-title { margin: 0 0 var(--space-1); font-weight: 600; }
.concept-box { margin: var(--space-2) 0 var(--space-3) var(--space-5); }
.concepts { margin-top: var(--space-2); padding: var(--space-3); border: 1px solid var(--color-line);
  border-radius: var(--radius-1); background: var(--color-surface); display: flex; flex-direction: column; gap: var(--space-2); }
.concepts-head { display: flex; flex-wrap: wrap; align-items: center; justify-content: space-between; gap: var(--space-2); }
.concepts-goal { font-size: 13px; min-width: 0; overflow-wrap: anywhere; }
.concept-empty { margin: 0; font-size: 13px; }
/* one control: a field and its own button share a border, so they read as a pair */
.add-group { display: flex; max-width: 360px; border: 1px solid var(--color-line); border-radius: var(--radius-pill);
  background: var(--color-bg); overflow: hidden; }
.add-group:focus-within { border-color: var(--color-accent); box-shadow: 0 0 0 2px var(--color-accent-soft); }
.add-input { flex: 1 1 auto; min-width: 0; border: 0; background: transparent; padding: 6px 12px; font: inherit; font-size: 14px; color: var(--color-text); }
.add-input:focus { outline: none; }
.add-button { border: 0; border-left: 1px solid var(--color-line); border-radius: 0; padding: 6px 14px; font-size: 14px; font-weight: 600;
  color: var(--color-accent); background: var(--color-surface); }
.add-button:hover { background: var(--color-accent-soft); }
.resource-form { margin-top: var(--space-2); padding: var(--space-3); border: 1px dashed var(--color-line); border-radius: var(--radius-1); }
details.resource { padding: var(--space-1) 0; border-top: 1px solid var(--color-line); }
details.resource summary { cursor: pointer; }
details.resource .preview { font-size: 13px; white-space: pre-wrap; overflow-wrap: anywhere; }
.section-toggle { font: inherit; font-weight: 600; padding: 0; }
@media (max-width: 600px) { .concept-box { margin-left: 0; } }

/* D67: what students do, chosen first when making an environment */
.kind-cards { display: grid; grid-template-columns: repeat(auto-fit, minmax(220px, 1fr)); gap: var(--space-3); margin-bottom: var(--space-3); }
.choice-card { display: flex; flex-direction: column; gap: var(--space-1); text-align: left; padding: var(--space-4);
               border: 1px solid var(--color-line); border-radius: var(--radius-md); background: var(--color-surface); cursor: pointer; }
.choice-card .card-desc { color: var(--color-muted); font-size: var(--text-sm); }
.choice-card[aria-pressed="true"] { border-color: var(--color-accent); background: var(--color-accent-soft); }
.family-note { margin: 0 0 var(--space-3); }
.inline-search { font-weight: 600; color: var(--color-accent); text-decoration: underline; text-underline-offset: 2px; }
.class-programmes { display: flex; flex-direction: column; gap: var(--space-2); }
.class-row { display: grid; grid-template-columns: max-content 1fr; align-items: center; gap: var(--space-2); }
.profile-block { padding: var(--space-3); margin-bottom: var(--space-3); border: 1px solid var(--color-line); border-radius: var(--radius-md); }
.profile-block p { margin: var(--space-1) 0 0; }
.programme-add { display: grid; grid-template-columns: max-content 1fr max-content; gap: var(--space-2); }
.publish-row { display: flex; flex-wrap: wrap; align-items: center; gap: var(--space-2); margin-bottom: var(--space-2); }
/* D69: an environment this class does not have yet */
.card.unlinked { position: relative; background: var(--color-surface-2); cursor: default; }
.card.unlinked > :not(.card-add) { opacity: .55; }
.card.unlinked:hover > :not(.card-add) { opacity: .8; }
.card-add { position: absolute; top: var(--space-3); right: var(--space-3); width: 36px; height: 36px; border-radius: 50%;
            font-size: 22px; line-height: 1; border: 1px solid var(--color-accent); color: var(--color-accent); background: var(--color-surface);
            display: flex; align-items: center; justify-content: center; padding: 0; }
.card-wrap { position: relative; display: flex; }
.card-wrap > .card { flex: 1; }
.card-remove { font-size: 24px; }
.card-remove:disabled { opacity: .35; cursor: not-allowed; }
.card-trash { border-color: var(--color-line); color: var(--color-muted); }
.card-trash:hover { border-color: var(--color-danger); color: var(--color-danger); background: var(--color-surface); }
.card-confirm { cursor: default; border-color: var(--color-danger); }
.card-confirm:hover { background: var(--color-surface); }
button.danger { background: var(--color-danger); border-color: var(--color-danger); color: #fff; font-weight: 600; }
button.danger:hover { filter: brightness(1.06); background: var(--color-danger); }

/* School deployment (D83, D85): signing in, choosing a password, and the school roster */
body[data-view="roster"] .demo-bar { display: none !important; }
.login { flex: 1; display: grid; place-items: center; padding: var(--space-6) var(--space-4); }
.login-card { display: flex; flex-direction: column; gap: var(--space-3); width: min(420px, 100%); padding: var(--space-6);
              background: var(--color-surface); border-radius: var(--radius-3); box-shadow: var(--shadow-2); }
.login-card .display { margin: 0; font-size: var(--text-xl); }
.login-card .error { margin: 0; }
.login-input { padding: 11px 14px; border: 1px solid var(--color-line); border-radius: var(--radius-1); background: var(--color-bg); }
.roster-code .username { font: var(--text-md)/1.2 var(--font-mono); color: var(--color-muted); }
.roster { flex: 1; min-height: 0; overflow-y: auto; padding: var(--space-6) max(var(--space-4), calc((100% - 880px) / 2)) var(--space-7); }
.roster > .display { margin: 0 0 var(--space-2); font-size: var(--text-display); }
.roster .form-card { margin-top: var(--space-5); }
.roster h4 { margin: var(--space-4) 0 var(--space-2); font-size: var(--text-sm); color: var(--color-muted); }
.roster-list { list-style: none; margin: 0; padding: 0; }
.roster-person, .roster-code { display: flex; flex-wrap: wrap; align-items: center; gap: var(--space-2) var(--space-3);
                               padding: var(--space-2) 0; border-bottom: 1px solid var(--color-line); }
.roster-person > span:first-child, .roster-code > span { flex: 1; min-width: 140px; }
.roster-code code { font: var(--text-lg)/1.2 var(--font-mono); letter-spacing: .06em; }
.roster-add { display: flex; flex-wrap: wrap; gap: var(--space-2); margin-top: var(--space-3); }
.roster-input { padding: 8px 10px; border: 1px solid var(--color-line); border-radius: var(--radius-1);
                background: var(--color-surface); max-width: 100%; }
.roster-input { flex: 1; min-width: 180px; }
.roster-class { margin-top: var(--space-3); }
@media print {
  body { height: auto; overflow: visible; }
  body > :not(#roster), .roster > :not(.roster-codes), .roster-codes .ask-actions, .roster-codes .hint { display: none !important; }
  .roster-codes { box-shadow: none; }
  .roster-code { break-inside: avoid; padding: var(--space-4) 0; }
}