:root{
  --bg:#f6f8fc;--surface:#fff;--surface-2:#eef4ff;--text:#172033;--muted:#65708a;
  --primary:#4f46e5;--primary-2:#4338ca;--accent:#15a083;--danger:#c43b52;--warning:#a96b00;
  --border:#dfe5f0;--shadow:0 18px 45px rgba(35,58,110,.10);--radius:18px;--radius-sm:12px;
}
*{box-sizing:border-box}html{scroll-behavior:smooth}body{margin:0;font-family:Inter,ui-sans-serif,system-ui,-apple-system,BlinkMacSystemFont,"Segoe UI",sans-serif;background:var(--bg);color:var(--text);line-height:1.55}
a{color:inherit;text-decoration:none}button,input,select,textarea{font:inherit}.container{width:min(1160px,calc(100% - 32px));margin-inline:auto}.hidden{display:none!important}
.site-header{position:sticky;top:0;z-index:20;background:rgba(255,255,255,.94);border-bottom:1px solid var(--border);backdrop-filter:blur(16px)}.navbar{min-height:72px;display:flex;align-items:center;justify-content:space-between;gap:20px}.brand{display:inline-flex;align-items:center;gap:10px;font-weight:800;font-size:1.12rem}.brand-mark{width:36px;height:36px;border-radius:11px;background:linear-gradient(145deg,var(--primary),#a5b4fc);display:grid;place-items:center;color:#fff;box-shadow:0 8px 18px rgba(79,70,229,.25)}.nav-links{display:flex;align-items:center;gap:4px;flex-wrap:wrap}.nav-links a{padding:9px 11px;border-radius:10px;color:#48536a;font-size:.93rem}.nav-links a:hover,.nav-links a.active{background:#edf2ff;color:var(--primary);font-weight:700}.mobile-toggle{display:none;border:1px solid var(--border);background:#fff;border-radius:10px;padding:7px 10px}
.hero{padding:70px 0 54px;background:radial-gradient(circle at 85% 10%,#dfe9ff 0,transparent 34%),linear-gradient(180deg,#fff,#f7f9fd)}.hero-grid{display:grid;grid-template-columns:1.05fr .95fr;gap:48px;align-items:center}.eyebrow,.badge{display:inline-flex;align-items:center;gap:7px;padding:7px 10px;border-radius:999px;background:#edf2ff;color:var(--primary);font-size:.82rem;font-weight:800}.hero h1,.page-hero h1{font-size:clamp(2.2rem,5vw,4.4rem);line-height:1.05;margin:16px 0}.hero p,.lead{font-size:1.05rem;color:var(--muted);max-width:720px}.hero-actions{display:flex;gap:12px;flex-wrap:wrap;margin-top:24px}.dashboard-preview{background:#14203d;color:#fff;border-radius:24px;padding:20px;box-shadow:0 30px 75px rgba(25,42,85,.24)}.preview-top{display:flex;justify-content:space-between;gap:10px}.preview-chip{font-size:.76rem;background:#26375e;padding:5px 9px;border-radius:999px}.preview-grid{display:grid;grid-template-columns:1fr 1fr;gap:12px;margin-top:18px}.preview-card{background:#1e2c50;border:1px solid rgba(255,255,255,.08);padding:14px;border-radius:14px;color:#dce5ff}.preview-card strong{display:block;color:#fff;font-size:1.45rem;margin-top:6px}
.section{padding:54px 0}.section-header{display:flex;justify-content:space-between;align-items:end;gap:18px;margin-bottom:22px}.section-header h2,.card h2{margin:0 0 8px}.section-header p{margin:0;color:var(--muted)}.grid-2{display:grid;grid-template-columns:repeat(2,minmax(0,1fr));gap:20px}.grid-3{display:grid;grid-template-columns:repeat(3,minmax(0,1fr));gap:20px}.grid-4{display:grid;grid-template-columns:repeat(4,minmax(0,1fr));gap:16px}.card,.panel{background:var(--surface);border:1px solid var(--border);border-radius:var(--radius);box-shadow:0 8px 30px rgba(39,55,93,.05)}.card{padding:22px}.card p{color:var(--muted)}.card-icon{font-size:1.7rem}.kpi{font-size:1.8rem;font-weight:900;margin-top:5px}.muted{color:var(--muted)}
.btn{border:0;border-radius:11px;padding:11px 15px;display:inline-flex;align-items:center;justify-content:center;gap:7px;font-weight:800;cursor:pointer;transition:.18s}.btn:hover{transform:translateY(-1px)}.btn-primary{background:var(--primary);color:#fff}.btn-primary:hover{background:var(--primary-2)}.btn-secondary{background:#eef2f8;color:#26334f;border:1px solid #dce3ef}.btn-danger{background:#fff0f2;color:var(--danger);border:1px solid #f3cbd2}.btn-small{padding:8px 11px;font-size:.88rem}.btn:disabled{opacity:.55;cursor:not-allowed;transform:none}
.page-hero{padding:48px 0 30px;background:linear-gradient(180deg,#fff,#f7f9fd)}.page-hero h1{font-size:clamp(2rem,4vw,3.4rem)}.filters,.form-row{display:grid;grid-template-columns:repeat(2,minmax(0,1fr));gap:14px}.form-group{display:grid;gap:7px;margin-bottom:13px}.form-group label{font-weight:750;font-size:.92rem}.input,.select,.textarea{width:100%;border:1px solid #d7deea;border-radius:11px;padding:11px 12px;background:#fff;color:var(--text);outline:none}.input:focus,.select:focus,.textarea:focus{border-color:#8aa5ff;box-shadow:0 0 0 3px rgba(49,88,212,.10)}.textarea{min-height:96px;resize:vertical}.helper{font-size:.82rem;color:var(--muted)}.notice{border:1px solid #cddbf7;background:#eef4ff;color:#29406e;padding:12px 14px;border-radius:12px}.notice.success{background:#eaf9f3;border-color:#bee8d9;color:#12674f}.notice.error{background:#fff0f2;border-color:#f0c4cd;color:#8f2940}.notice.warning{background:#fff7e8;border-color:#f2d9a5;color:#805400}
.subject-tabs{display:flex;gap:8px;flex-wrap:wrap;margin:16px 0}.lesson-card{display:grid;gap:10px}.lesson-card ul{margin:0;padding-left:19px;color:#4e5a71}.lesson-meta{display:flex;justify-content:space-between;gap:10px;align-items:center}.tag{font-size:.75rem;padding:5px 8px;border-radius:999px;background:#f0f3f9;color:#56637b}.progress-bar{height:9px;background:#e9edf5;border-radius:999px;overflow:hidden}.progress-bar>span{display:block;height:100%;background:linear-gradient(90deg,var(--primary),var(--accent));border-radius:inherit}
.planner-list,.conversation-list,.notes-list{display:grid;gap:10px}.session,.conversation-item,.note-card{border:1px solid var(--border);border-radius:12px;padding:12px;background:#fff}.session{display:flex;align-items:center;justify-content:space-between;gap:12px}.session small,.conversation-item small{display:block;color:var(--muted)}.conversation-item{text-align:left;cursor:pointer}.conversation-item.active{border-color:#9ab0f2;background:#f2f5ff}.conversation-item strong{display:flex;align-items:center;justify-content:space-between;gap:10px}.unread-dot{width:9px;height:9px;border-radius:50%;background:var(--primary);display:inline-block}.empty{padding:18px;border:1px dashed #ccd4e3;border-radius:12px;color:var(--muted);text-align:center}
.quiz-layout{display:grid;grid-template-columns:1fr 300px;gap:22px;align-items:start}.question-card{padding:20px;margin-bottom:15px}.question-title{font-weight:850;margin-bottom:12px}.choices{display:grid;gap:9px}.choice{display:flex;gap:10px;align-items:flex-start;border:1px solid var(--border);padding:10px 11px;border-radius:11px;cursor:pointer}.choice:hover{background:#f8faff}.choice.correct{border-color:#82cdb7;background:#effaf6}.choice.wrong{border-color:#eab0ba;background:#fff3f5}.correction{margin-top:10px;padding:10px 12px;border-radius:10px;background:#f6f8fc;color:#47536a}.sticky{position:sticky;top:92px}.score-big{font-size:2.5rem;font-weight:900}.print-only{display:none}
.member-shell{min-height:100vh;background:#f3f6fb}.member-topbar{background:#fff;border-bottom:1px solid var(--border)}.member-topbar .container{min-height:70px;display:flex;align-items:center;justify-content:space-between;gap:14px}.member-body{padding:30px 0 50px}.auth-wrap{max-width:760px;margin:30px auto}.auth-card{background:#fff;border:1px solid var(--border);border-radius:22px;padding:28px;box-shadow:var(--shadow)}.auth-tabs{display:flex;gap:8px;margin:18px 0}.auth-tabs button.active{background:var(--primary);color:#fff}.user-pill{font-size:.86rem;background:#eef2ff;color:var(--primary);padding:7px 10px;border-radius:999px;font-weight:800}.member-dashboard{display:grid;grid-template-columns:1.15fr .85fr;gap:20px}.member-actions{display:flex;gap:10px;flex-wrap:wrap}.terminal-gate{margin-top:20px}.chat-app{display:grid;grid-template-columns:250px minmax(0,1fr) 280px;gap:14px;align-items:stretch}.panel{overflow:hidden}.panel-head{padding:13px 15px;border-bottom:1px solid var(--border);display:flex;align-items:center;justify-content:space-between;gap:10px;background:#fbfcff}.panel-body{padding:14px}.chat-panel{display:grid;grid-template-rows:auto minmax(420px,1fr) auto;min-height:650px}.messages{padding:16px;overflow:auto;background:#f9fbfe}.message{display:flex;flex-direction:column;align-items:flex-start;margin:8px 0}.message.mine{align-items:flex-end}.bubble{max-width:min(80%,650px);padding:10px 12px;border-radius:14px;background:#fff;border:1px solid var(--border);white-space:pre-wrap;overflow-wrap:anywhere}.message.mine .bubble{background:#eaf0ff;border-color:#cbd8ff}.message-meta{font-size:.72rem;color:var(--muted);margin-top:4px}.attachment{display:flex;gap:8px;align-items:center;margin-top:7px;padding:8px 10px;border:1px solid var(--border);border-radius:10px;background:#fff}.attachment button{border:0;background:#eef2ff;color:var(--primary);border-radius:8px;padding:6px 8px;cursor:pointer}.composer{padding:13px;border-top:1px solid var(--border);background:#fff}.composer-row{display:grid;grid-template-columns:1fr auto;gap:9px}.file-row{display:flex;gap:9px;align-items:center;flex-wrap:wrap;margin-top:8px}.bell{position:relative;border:1px solid var(--border);background:#fff;border-radius:10px;padding:8px 11px;cursor:pointer}.bell-count{position:absolute;top:-7px;right:-7px;min-width:20px;height:20px;padding:0 5px;border-radius:999px;background:var(--danger);color:#fff;font-size:.7rem;display:grid;place-items:center;font-weight:900}.demo-banner{background:#fff7e8;border:1px solid #f1d8a6;border-radius:12px;padding:10px 12px;color:#805400;margin-bottom:12px}
.terminal-wrap{display:grid;gap:14px}.terminal-titlebar{display:flex;align-items:center;justify-content:space-between;gap:12px;flex-wrap:wrap}.terminal-toolbar{display:flex;gap:8px;align-items:center}.offline-pill{font-size:.76rem;padding:5px 8px;border-radius:999px;background:#eef2f8;color:#56637b}
.site-footer{background:#111a31;color:#d8e0f3;margin-top:50px}.footer-inner{padding:38px 0;display:grid;grid-template-columns:1.2fr .8fr .8fr;gap:28px}.site-footer .lead{color:#aeb9d2;font-size:.92rem}.footer-links{display:grid;gap:7px;color:#b9c3d9}.member-link{opacity:.8}.footer-bottom{border-top:1px solid #26314d;padding:14px 0;color:#96a3bf;font-size:.83rem}
.install-banner{display:none;position:fixed;left:16px;right:16px;bottom:16px;z-index:40;background:#14203d;color:#fff;border-radius:15px;padding:13px 14px;box-shadow:var(--shadow);align-items:center;justify-content:space-between;gap:12px}.install-banner.show{display:flex}
@media(max-width:980px){.hero-grid,.quiz-layout,.member-dashboard{grid-template-columns:1fr}.grid-4{grid-template-columns:repeat(2,1fr)}.chat-app{grid-template-columns:1fr}.chat-panel{min-height:570px}.sticky{position:static}.notes-panel{order:3}}
@media(max-width:760px){.mobile-toggle{display:block}.nav-links{display:none;position:absolute;top:68px;left:16px;right:16px;background:#fff;border:1px solid var(--border);border-radius:14px;box-shadow:var(--shadow);padding:8px;flex-direction:column;align-items:stretch}.nav-links.open{display:flex}.nav-links a{padding:11px 12px}.hero{padding-top:44px}.hero-grid,.grid-2,.grid-3,.grid-4,.filters,.form-row,.footer-inner{grid-template-columns:1fr}.preview-grid{grid-template-columns:1fr 1fr}.section{padding:38px 0}.composer-row{grid-template-columns:1fr}.member-topbar .container{align-items:center}.session{align-items:flex-start;flex-direction:column}.auth-card{padding:20px}}
@media(max-width:430px){.container{width:min(100% - 22px,1160px)}.preview-grid{grid-template-columns:1fr}.hero h1{font-size:2.35rem}.btn{width:100%}.hero-actions .btn,.member-actions .btn,.file-row .btn,.terminal-toolbar .btn{width:auto}.bubble{max-width:92%}}
@media print{.site-header,.site-footer,.no-print,.btn,.install-banner{display:none!important}body{background:#fff}.container{width:100%;max-width:none}.card,.question-card{box-shadow:none;border:1px solid #bbb;break-inside:avoid}.print-only{display:block}.page-hero{padding:10px 0}.section{padding:12px 0}.quiz-layout{display:block}.sticky{display:none}}


/* StudyHub Network v1 additions */
:root{--surface:#fff;--surface-soft:#f5f7ff;--ink:#182033;--muted-2:#6a7285;--line:#e3e7f0;--accent:#3158d4;--accent-2:#5c7bea;--success:#16805b;--warning:#a36200;--danger:#b42318}
body{color:var(--ink)}
.nav-links a[aria-current="page"]{color:var(--accent);font-weight:800}
.toast{position:fixed;right:20px;bottom:20px;max-width:min(420px,calc(100vw - 40px));padding:14px 16px;border-radius:14px;background:#1f2937;color:white;box-shadow:0 14px 38px rgba(15,23,42,.22);opacity:0;transform:translateY(12px);pointer-events:none;transition:.2s;z-index:9999}.toast.show{opacity:1;transform:none}.toast[data-type="success"]{background:#176b4e}.toast[data-type="error"]{background:#9f2d25}
.quick-search{display:flex;gap:10px;align-items:center;margin-top:18px}.quick-search .input{min-width:0}
.favorite-btn{border:1px solid var(--line);background:#fff;border-radius:10px;padding:7px 10px;cursor:pointer;font-size:18px;line-height:1}.favorite-btn.active{background:#fff7cf;border-color:#f2ce4c}.lesson-actions{display:flex;gap:8px;flex-wrap:wrap;align-items:center;margin-top:14px}
.tool-grid{display:grid;grid-template-columns:repeat(3,minmax(0,1fr));gap:16px}.tool-card{display:block;text-decoration:none;color:inherit}.tool-card:hover{transform:translateY(-2px)}
.access-card{border:1px solid #dce3f6;background:linear-gradient(180deg,#fff,#f7f9ff)}
.workspace-shell{display:grid;grid-template-columns:270px 1fr;gap:18px;min-height:560px}.workspace-sidebar{border:1px solid var(--line);background:var(--surface);border-radius:18px;padding:14px}.workspace-main{border:1px solid var(--line);background:var(--surface);border-radius:18px;display:flex;flex-direction:column;min-width:0}.workspace-title{display:flex;align-items:center;justify-content:space-between;padding:16px 18px;border-bottom:1px solid var(--line);gap:12px}.partner-card{padding:12px;border-radius:14px;background:#f6f8fd}.message-list{padding:18px;overflow:auto;flex:1;min-height:320px;max-height:58vh}.msg-row{display:flex;margin:8px 0}.msg-row.mine{justify-content:flex-end}.msg-bubble{max-width:min(74%,620px);padding:10px 13px;border-radius:16px;background:#f0f3f8;border:1px solid #e4e8ef;white-space:pre-wrap;overflow-wrap:anywhere}.msg-row.mine .msg-bubble{background:#eaf0ff;border-color:#cfdbff}.msg-meta{font-size:12px;color:var(--muted-2);margin-top:4px}.msg-attachment{display:inline-flex;gap:6px;align-items:center;margin-top:8px;padding:7px 9px;background:#fff;border:1px solid var(--line);border-radius:10px;color:var(--accent);text-decoration:none}.composer{padding:14px 16px;border-top:1px solid var(--line);background:#fbfcff}.composer-line{display:grid;grid-template-columns:auto 1fr auto;gap:8px;align-items:end}.composer textarea{min-height:44px;max-height:130px;resize:vertical}.file-pill{font-size:12px;color:var(--muted-2);margin-top:8px}.bell{position:relative}.bell-count{position:absolute;right:-5px;top:-6px;min-width:18px;height:18px;border-radius:999px;background:#d92d20;color:#fff;font-size:11px;display:grid;place-items:center;padding:0 5px}.bell-count.hidden{display:none}
.shared-note{margin-top:12px}.shared-note textarea{min-height:110px}
.kpi-grid{display:grid;grid-template-columns:repeat(3,minmax(0,1fr));gap:12px}.kpi-card{padding:14px;border:1px solid var(--line);border-radius:14px;background:#fff}.kpi-number{font-size:30px;font-weight:800;line-height:1.1}.muted{color:var(--muted-2)}
.diag-list{display:grid;gap:10px}.diag-row{display:flex;justify-content:space-between;gap:16px;padding:12px 14px;border:1px solid var(--line);border-radius:12px;background:#fff}.diag-status{font-weight:800}.diag-status.ok{color:var(--success)}.diag-status.warn{color:var(--warning)}.diag-status.bad{color:var(--danger)}
.flashcard{perspective:900px;min-height:220px;cursor:pointer}.flashcard-inner{position:relative;min-height:220px;transition:transform .45s;transform-style:preserve-3d}.flashcard.flipped .flashcard-inner{transform:rotateY(180deg)}.flash-face{position:absolute;inset:0;backface-visibility:hidden;border:1px solid var(--line);border-radius:18px;background:#fff;padding:22px;display:flex;flex-direction:column;justify-content:center;align-items:center;text-align:center}.flash-back{transform:rotateY(180deg);background:#f5f8ff}
.search-result{padding:14px 0;border-bottom:1px solid var(--line)}.search-result:last-child{border-bottom:0}.search-highlight{background:#fff1a8;padding:0 2px;border-radius:3px}
.sync-pill{display:inline-flex;align-items:center;gap:6px;font-size:12px;padding:5px 9px;border-radius:999px;background:#eef2f7;color:#465066}.sync-pill.ok{background:#e9f8f1;color:#176b4e}
@media(max-width:820px){.tool-grid{grid-template-columns:1fr 1fr}.workspace-shell{grid-template-columns:1fr}.workspace-sidebar{order:2}.workspace-main{order:1}.message-list{max-height:52vh}.kpi-grid{grid-template-columns:1fr}.composer-line{grid-template-columns:auto 1fr}.composer-line .send-btn{grid-column:1/-1}.msg-bubble{max-width:88%}}
@media(max-width:560px){.tool-grid{grid-template-columns:1fr}.quick-search{flex-direction:column;align-items:stretch}}

.sr-only{position:absolute;width:1px;height:1px;padding:0;margin:-1px;overflow:hidden;clip:rect(0,0,0,0);white-space:nowrap;border:0}