:root{
  --ink:#153044; --muted:#6d7f8f; --line:#dfe9ee; --panel:#fff; --bg:#f4f8f9;
  --teal:#0d6b6e; --teal2:#13969a; --tealSoft:#e7f6f5; --navy:#183f64;
  --pink:#f3dfe7; --blue:#e7efff; --green:#e4f4e9; --orange:#fff0d8; --purple:#eee8fb;
  --danger:#b44c5a; --shadow:0 10px 30px rgba(27,68,87,.08); --r:18px;
}
*{box-sizing:border-box}html,body{margin:0;min-height:100%;font-family:Inter,ui-sans-serif,-apple-system,BlinkMacSystemFont,"Segoe UI",sans-serif;color:var(--ink);background:var(--bg)}button,input,select,textarea{font:inherit}button{cursor:pointer}.app-shell{min-height:100vh;display:grid;grid-template-columns:250px minmax(0,1fr)}
.sidebar{position:sticky;top:0;height:100vh;background:#fff;border-right:1px solid var(--line);padding:18px 14px;display:flex;flex-direction:column;z-index:20}.brand{border:0;background:transparent;display:flex;align-items:center;gap:10px;text-align:left;padding:6px;margin-bottom:22px;color:var(--ink)}.brand strong{display:block;font-size:16px}.brand small{display:block;color:var(--muted);font-size:11px;margin-top:2px}.brand-mark{width:34px;height:34px;position:relative;display:inline-flex;gap:2px}.brand-mark span{flex:1;border:2px solid var(--teal);border-radius:4px 4px 10px 2px;background:linear-gradient(145deg,#fff,#dff4f2)}.brand-mark span:last-child{transform:scaleX(-1)}
.nav{display:grid;gap:6px}.nav-item{width:100%;border:0;background:transparent;border-radius:12px;padding:11px 12px;display:flex;align-items:center;gap:10px;color:#4b6474;text-align:left}.nav-item span{width:20px;text-align:center}.nav-item b{font-weight:650}.nav-item:hover{background:#f2f7f7}.nav-item.active{background:var(--teal);color:#fff}.sidebar-foot{margin-top:auto;border-top:1px solid var(--line);padding-top:10px}.teacher-mini{display:flex;align-items:center;gap:9px;padding:12px}.teacher-mini strong,.teacher-mini small{display:block}.teacher-mini small{font-size:11px;color:var(--muted);margin-top:2px}.avatar{width:34px;height:34px;border-radius:50%;display:grid;place-items:center;background:var(--navy);color:white;font-size:12px;font-weight:800;flex:none}
.main{min-width:0}.topbar{height:82px;background:rgba(255,255,255,.94);backdrop-filter:blur(8px);border-bottom:1px solid var(--line);padding:13px 30px;display:flex;align-items:center;justify-content:space-between;position:sticky;top:0;z-index:10}.topbar h1{font-size:22px;margin:2px 0 0}.eyebrow{text-transform:uppercase;letter-spacing:.08em;font-size:10px;font-weight:800;color:var(--teal)}.top-actions{display:flex;align-items:center;gap:10px}.class-chip,.pill,.tag,.status{display:inline-flex;align-items:center;border-radius:999px;white-space:nowrap}.class-chip{padding:8px 12px;background:#eef5f6;font-size:12px;font-weight:700}.view{padding:28px 30px 50px;max-width:1440px;margin:0 auto}.mobile-menu{display:none;border:0;background:transparent;font-size:24px}
.hero-row{display:flex;justify-content:space-between;gap:18px;align-items:flex-end;margin-bottom:20px}.hero-row h2{font-size:27px;margin:0 0 5px}.hero-row p{margin:0;color:var(--muted);max-width:780px}.hero-actions{display:flex;gap:8px;flex-wrap:wrap}.panel{background:var(--panel);border:1px solid var(--line);border-radius:var(--r);box-shadow:var(--shadow);padding:20px}.panel + .panel{margin-top:16px}.panel-heading{display:flex;align-items:center;justify-content:space-between;gap:16px;margin-bottom:14px}.panel h3{margin:0 0 4px;font-size:17px}.panel p{color:var(--muted);margin:0;line-height:1.55}.metric-grid{display:grid;grid-template-columns:repeat(4,minmax(0,1fr));gap:14px;margin-bottom:18px}.metric-card{border:1px solid var(--line);background:#fff;border-radius:16px;padding:17px;text-align:left;box-shadow:var(--shadow);min-height:135px}.metric-card strong{display:block;font-size:28px;margin:8px 0 3px}.metric-card span.label{display:block;color:#3f5665;font-size:13px;line-height:1.35}.metric-card small{display:block;margin-top:8px;color:var(--teal);font-weight:750}.metric-icon{width:35px;height:35px;border-radius:10px;display:grid;place-items:center;font-weight:900}.i-pink{background:var(--pink)}.i-green{background:var(--green)}.i-orange{background:var(--orange)}.i-blue{background:var(--blue)}
.grid-2{display:grid;grid-template-columns:minmax(0,1.4fr) minmax(280px,.6fr);gap:16px}.grid-3{display:grid;grid-template-columns:repeat(3,minmax(0,1fr));gap:14px}.stack{display:grid;gap:14px}.table-wrap{overflow:auto;border-radius:12px;border:1px solid var(--line)}table{width:100%;border-collapse:collapse;min-width:750px;background:#fff}th,td{text-align:left;padding:11px 12px;border-bottom:1px solid #eaf0f2;font-size:12px}th{background:#f7fafb;color:#607585;font-size:11px;text-transform:uppercase;letter-spacing:.035em}tr:last-child td{border-bottom:0}.student-cell{display:flex;align-items:center;gap:8px;font-weight:750}.mini-avatar{width:28px;height:28px;border-radius:50%;display:grid;place-items:center;font-size:11px;background:#e9f3f3;color:var(--teal);font-weight:800}.tag{padding:5px 8px;background:#eef5f6;color:#476274;font-size:11px}.tag.good{background:var(--green);color:#287342}.tag.warn{background:var(--orange);color:#8c5d18}.tag.need{background:#fae8eb;color:#9c4755}.tag.challenge{background:var(--purple);color:#684fa0}
button.primary,button.secondary,button.danger,.text-btn{border-radius:10px;padding:9px 13px;font-weight:750}.primary{border:1px solid var(--teal);background:var(--teal);color:#fff}.primary:hover{background:#0a5b5d}.secondary{border:1px solid var(--line);background:#fff;color:var(--ink)}.secondary:hover{background:#f7fafb}.danger{border:1px solid #efd5da;background:#fff3f5;color:var(--danger)}.text-btn{border:0;background:transparent;color:var(--teal);padding:6px}.wide{width:100%}.small-btn{padding:6px 9px!important;font-size:11px!important}.button-row{display:flex;gap:8px;flex-wrap:wrap}.notice{border:1px solid #cde8e6;background:var(--tealSoft);padding:13px 14px;border-radius:12px;color:#355f60;font-size:13px;line-height:1.5}.notice.warning{background:#fff8e8;border-color:#f4e0ad;color:#725822}.empty{padding:34px;text-align:center;border:1px dashed #bfd0d7;border-radius:14px;color:var(--muted)}
.student-grid{display:grid;grid-template-columns:repeat(3,minmax(0,1fr));gap:14px}.student-card{background:#fff;border:1px solid var(--line);border-radius:16px;padding:16px;box-shadow:var(--shadow)}.student-card-head{display:flex;justify-content:space-between;gap:10px}.student-card .student-cell{font-size:15px}.student-card dl,.profile-stats{display:grid;grid-template-columns:1fr 1fr;gap:10px;margin:15px 0}.student-card dt,.profile-stats small{font-size:10px;text-transform:uppercase;color:var(--muted);letter-spacing:.05em}.student-card dd{margin:3px 0 0;font-weight:800}.progress{height:8px;background:#edf2f3;border-radius:999px;overflow:hidden}.progress span{display:block;height:100%;background:var(--teal2);border-radius:999px}.profile-head{display:flex;gap:16px;align-items:flex-start}.profile-head .avatar{width:58px;height:58px;font-size:16px}.profile-head h2{margin:0}.profile-head p{margin:4px 0;color:var(--muted)}.profile-stats>div{background:#f7fafb;border-radius:12px;padding:12px}.profile-stats strong{display:block;font-size:18px;margin-top:4px}
form label{display:grid;gap:6px;font-size:12px;font-weight:750;color:#415868}input,select,textarea{width:100%;border:1px solid #cfdde2;border-radius:10px;padding:10px 11px;background:#fff;color:var(--ink);outline:none}textarea{resize:vertical;min-height:90px}input:focus,select:focus,textarea:focus{border-color:var(--teal2);box-shadow:0 0 0 3px rgba(19,150,154,.10)}.form-grid{display:grid;grid-template-columns:repeat(2,minmax(0,1fr));gap:13px}.form-grid .full{grid-column:1/-1}.form-actions{margin-top:14px;display:flex;gap:8px;justify-content:flex-end}.filters{display:flex;gap:8px;flex-wrap:wrap}.filters button{border:1px solid var(--line);background:#fff;border-radius:999px;padding:7px 10px;font-size:11px}.filters button.active{background:var(--teal);border-color:var(--teal);color:#fff}
.story-layout{display:grid;grid-template-columns:minmax(320px,.65fr) minmax(0,1.35fr);gap:16px}.story-preview h2{font-family:Georgia,serif;font-size:27px;margin:0 0 10px}.story-preview .story-meta{display:flex;gap:7px;flex-wrap:wrap;margin:10px 0 18px}.story-text{font-family:Georgia,serif;font-size:16px;line-height:1.8;color:#293d49;white-space:pre-wrap}.story-card{border:1px solid var(--line);border-radius:14px;padding:15px;background:#fff}.story-card+.story-card{margin-top:10px}.story-card h4{margin:0 0 6px}.story-card p{font-size:13px}.story-list{display:grid;gap:10px}.story-list .story-card{display:flex;justify-content:space-between;gap:16px;align-items:flex-start}.word-chips{display:flex;gap:6px;flex-wrap:wrap}.pill{font-size:11px;padding:5px 8px;background:#eef5f6}.pill.target{background:#fae7ee;color:#934761}.pill.mastered{background:#e4f4e9;color:#2a7747}
.assessment-shell{display:grid;grid-template-columns:minmax(0,1.25fr) minmax(300px,.75fr);gap:16px}.reading-pane{max-height:72vh;overflow:auto}.question{border-top:1px solid var(--line);padding:15px 0}.question:first-child{border-top:0;padding-top:0}.question p{font-weight:750;color:var(--ink);margin-bottom:9px}.option{display:flex;gap:8px;align-items:flex-start;margin:8px 0;font-size:13px}.option input{width:auto;margin-top:2px}.score-banner{padding:16px;border-radius:14px;background:var(--tealSoft);margin-bottom:12px}.score-banner strong{font-size:24px}.feedback-good{color:#2c7548}.feedback-bad{color:#a34b59}
.bars{display:grid;gap:11px}.bar-row{display:grid;grid-template-columns:90px 1fr 42px;gap:10px;align-items:center;font-size:12px}.bar-track{height:12px;background:#edf2f4;border-radius:99px;overflow:hidden}.bar-fill{height:100%;border-radius:99px;background:linear-gradient(90deg,var(--teal),#48b6ae)}.insight-card{padding:14px;border-radius:13px;background:#f5f9fa;border:1px solid var(--line)}.insight-card h4{margin:0 0 5px}.insight-card p{font-size:13px}.timeline{display:grid;gap:8px}.timeline-item{display:grid;grid-template-columns:90px 1fr;gap:12px;font-size:12px;border-bottom:1px solid var(--line);padding-bottom:8px}.timeline-item:last-child{border:0}.timeline-item time{color:var(--muted)}
.assistant-panel{max-width:980px}.chat-log{display:grid;gap:10px;min-height:260px;max-height:52vh;overflow:auto;padding:2px}.bubble{max-width:82%;padding:12px 14px;border-radius:15px;font-size:13px;line-height:1.55;white-space:pre-wrap}.bubble.user{justify-self:end;background:var(--navy);color:#fff;border-bottom-right-radius:4px}.bubble.ai{justify-self:start;background:#f2f7f8;border:1px solid var(--line);border-bottom-left-radius:4px}.quick-prompts{display:flex;gap:7px;flex-wrap:wrap;margin:14px 0}.quick-prompts button{border:1px solid #cfe0e5;background:#fff;border-radius:999px;padding:8px 10px;font-size:11px;color:#39596a}.chat-input{display:grid;grid-template-columns:1fr auto;gap:8px}.chat-input input{min-height:43px}
.data-actions{display:grid;grid-template-columns:repeat(3,minmax(0,1fr));gap:12px}.data-card{border:1px solid var(--line);border-radius:14px;padding:16px;background:#fff}.data-card h3{font-size:15px}.data-card p{font-size:12px;min-height:58px}.file-label{display:inline-flex;align-items:center}.file-label input{display:none}
.modal{border:0;padding:0;border-radius:18px;box-shadow:0 30px 80px rgba(0,0,0,.24);width:min(640px,92vw);max-height:88vh}.modal::backdrop{background:rgba(13,40,53,.36)}#modalBody{padding:22px}.modal-head{display:flex;justify-content:space-between;gap:10px;align-items:center;margin-bottom:16px}.modal-head h2{margin:0;font-size:20px}.close-x{border:0;background:#f2f5f6;width:32px;height:32px;border-radius:50%}.toast{position:fixed;z-index:100;right:22px;bottom:22px;background:#163d50;color:#fff;padding:11px 14px;border-radius:11px;box-shadow:var(--shadow);transform:translateY(90px);opacity:0;transition:.25s;font-size:12px}.toast.show{transform:none;opacity:1}
@media(max-width:1100px){.metric-grid,.student-grid{grid-template-columns:repeat(2,minmax(0,1fr))}.grid-2,.story-layout,.assessment-shell{grid-template-columns:1fr}.data-actions{grid-template-columns:1fr 1fr}}
@media(max-width:760px){.app-shell{display:block}.sidebar{position:fixed;left:-270px;width:250px;transition:.2s;box-shadow:20px 0 40px rgba(0,0,0,.12)}.sidebar.open{left:0}.main{width:100%}.topbar{height:72px;padding:10px 14px}.mobile-menu{display:block}.topbar>div:first-of-type{margin-right:auto;margin-left:9px}.topbar .secondary{display:none}.class-chip{max-width:120px;overflow:hidden;text-overflow:ellipsis}.view{padding:20px 14px 40px}.metric-grid,.student-grid,.grid-3,.data-actions{grid-template-columns:1fr}.grid-2{grid-template-columns:1fr}.form-grid{grid-template-columns:1fr}.form-grid .full{grid-column:auto}.hero-row{align-items:flex-start;flex-direction:column}.topbar h1{font-size:18px}.hero-row h2{font-size:24px}.modal{width:95vw}}
.class-switcher{display:grid;grid-template-columns:repeat(3,minmax(0,1fr));gap:10px}.class-tile{border:1px solid var(--line);border-radius:13px;padding:12px;background:#fff;text-align:left;color:var(--ink)}.class-tile strong,.class-tile small{display:block}.class-tile small{margin-top:5px;color:var(--muted)}.class-tile.active{border-color:var(--teal2);background:var(--tealSoft);box-shadow:inset 0 0 0 1px var(--teal2)}
@media(max-width:900px){.class-switcher{grid-template-columns:1fr 1fr}}@media(max-width:600px){.class-switcher{grid-template-columns:1fr}}

/* Phase 2: authentication + connection state */
.hidden{display:none!important}
.auth-gate{min-height:100vh;display:grid;place-items:center;padding:28px;background:radial-gradient(circle at top left,#e8f7f6 0,#f7fafb 42%,#eef4f7 100%)}
.auth-card{width:min(440px,100%);background:#fff;border:1px solid var(--line);border-radius:22px;padding:26px;box-shadow:0 24px 70px rgba(18,54,71,.14)}
.auth-brand{display:flex;align-items:center;gap:12px;margin-bottom:20px}.auth-brand>div{display:grid}.auth-brand strong{font-size:18px}.auth-brand small{color:var(--muted);margin-top:2px}.auth-form{display:grid;gap:12px;margin:16px 0 10px}.auth-card>.secondary{margin-top:4px}.auth-foot{font-size:11px;line-height:1.55;color:var(--muted);margin:18px 0 0}
.status-chip{display:inline-flex;align-items:center;gap:6px;padding:6px 9px;border-radius:999px;border:1px solid var(--line);background:#f5f8f9;color:#536d7b;font-size:10px;font-weight:800;white-space:nowrap}.status-chip:before{content:'';width:7px;height:7px;border-radius:50%;background:#8096a2}.status-chip.online{background:#eaf7ee;color:#2c7449;border-color:#cfe8d8}.status-chip.online:before{background:#3ea66a}.status-chip.saving{background:#fff8e9;color:#80611f;border-color:#efdca8}.status-chip.saving:before{background:#d49a22}.status-chip.error{background:#fff0f2;color:#9b4352;border-color:#efd3d8}.status-chip.error:before{background:#c95a6c}.status-chip.demo{background:#eef4f8;color:#4b6677}.status-chip.demo:before{background:#66869a}
button:disabled{opacity:.62;cursor:not-allowed}
@media(max-width:900px){#connectionStatus{display:none}#signOutTop{display:none!important}}