:root{
  --ink:#0d1117; --ink-soft:#4b5563; --muted:#8a919c;
  --paper:#ffffff; --paper-soft:#f6f7fa; --paper-alt:#eef1f7;
  --border:#e6e8ee; --border-soft:#eef0f4;
  --blue:#2f5bff; --blue-dim:#1f42cc; --blue-soft:#eaefff;
  --green:#1a9b62; --green-soft:#e7f8ef;
  --amber:#b5791b; --amber-soft:#fbf1de;
  --red:#d1453d; --red-soft:#fceeed;
  --shadow-sm:0 1px 2px rgba(16,24,40,.04);
  --shadow-md:0 10px 30px -12px rgba(16,24,40,.16);
  --shadow-lg:0 24px 60px -20px rgba(16,24,40,.22);
}
*{box-sizing:border-box} html,body{margin:0;padding:0}
body{background:radial-gradient(ellipse 900px 480px at 15% -10%,rgba(47,91,255,.07),transparent 60%),var(--paper-alt);color:var(--ink);font-family:'Inter',system-ui,sans-serif;min-height:100vh}
::selection{background:var(--blue);color:#fff} a{color:var(--blue)}
#app-shell{max-width:1040px;margin:0 auto;padding:40px 20px 80px}
#app{background:var(--paper);border:1px solid var(--border);border-radius:28px;box-shadow:var(--shadow-lg);padding:34px 40px 44px}
.eyebrow{font-family:'IBM Plex Mono',monospace;font-size:11px;letter-spacing:.14em;text-transform:uppercase;color:var(--blue);margin:0 0 6px;font-weight:500}
h1,h2,h3{margin:0;font-weight:800;letter-spacing:-.02em;color:var(--ink)} h1{font-size:30px} h2{font-size:19px} h3{font-size:15.5px}
p{line-height:1.6;color:var(--ink-soft)}
header.top{display:flex;align-items:flex-end;justify-content:space-between;padding-bottom:20px;margin-bottom:26px;border-bottom:1px solid var(--border);gap:16px;flex-wrap:wrap}
nav.tabs{display:flex;gap:2px;align-items:center;flex-wrap:wrap}
nav.tabs button{background:none;border:none;border-bottom:2px solid transparent;color:var(--muted);font:600 13.5px 'Inter',sans-serif;padding:8px 12px;cursor:pointer;transition:.15s}
nav.tabs button:hover{color:var(--ink)} nav.tabs button.active{color:var(--blue);border-bottom-color:var(--blue)}
.btn{font:600 13px 'Inter',sans-serif;padding:9px 15px;border-radius:10px;border:1px solid var(--border);background:var(--paper);color:var(--ink);cursor:pointer;transition:.15s}
.btn:hover{border-color:var(--muted);background:var(--paper-soft)} .btn.primary{background:var(--blue);border-color:var(--blue);color:#fff;box-shadow:var(--shadow-sm)} .btn.primary:hover{background:var(--blue-dim)}
.btn.danger{color:var(--red);border-color:#f3c4c1;background:var(--red-soft)} .btn.success{color:var(--green);border-color:#b8e8d2;background:var(--green-soft)} .btn.amber{color:var(--amber);border-color:#eed3a5;background:var(--amber-soft)}
.btn.sm{padding:6px 11px;font-size:12px;border-radius:8px}.btn:disabled{opacity:.55;cursor:not-allowed}
.row{display:flex;gap:10px;align-items:center;flex-wrap:wrap}.spacer{flex:1}.muted{color:var(--muted)}.mono{font-family:'IBM Plex Mono',monospace}.hidden{display:none!important}
.stat-grid{display:grid;grid-template-columns:repeat(auto-fit,minmax(140px,1fr));gap:12px;margin:18px 0 24px}
.stat-box{background:var(--paper-soft);border:1px solid var(--border);border-radius:14px;padding:16px}.stat-box .num{font-size:26px;font-weight:800}.stat-box .lbl{font:10px 'IBM Plex Mono',monospace;text-transform:uppercase;color:var(--muted);letter-spacing:.05em;margin-top:2px}
.index-card{background:var(--paper);border:1px solid var(--border);border-radius:18px;position:relative;padding:22px 24px 24px;box-shadow:var(--shadow-md);margin-bottom:16px;overflow:hidden}.index-card:before{content:'';position:absolute;left:0;right:0;top:0;height:5px;background:linear-gradient(90deg,var(--blue),#7fa0ff)}.index-card .kicker{font:600 10.5px 'IBM Plex Mono',monospace;text-transform:uppercase;letter-spacing:.1em;color:var(--blue);margin-bottom:10px}
.deck-grid{display:grid;grid-template-columns:repeat(auto-fit,minmax(250px,1fr));gap:14px}.deck-card{border:1px solid var(--border);border-radius:16px;padding:18px;background:var(--paper);transition:.15s}.deck-card:hover{border-color:var(--blue);box-shadow:var(--shadow-md)}.deck-title{font-size:16px;font-weight:750}.deck-meta{font:11px 'IBM Plex Mono',monospace;color:var(--muted);margin-top:8px}
.pill{font:10.5px 'IBM Plex Mono',monospace;padding:2px 9px;border-radius:20px;border:1px solid var(--border);color:var(--ink-soft);background:var(--paper)}.pill.blue{border-color:#c8d4ff;color:var(--blue);background:var(--blue-soft)}.pill.done{border-color:#b8e8d2;color:var(--green);background:var(--green-soft)}.pill.hard{border-color:#eed3a5;color:var(--amber);background:var(--amber-soft)}
.form-grid{display:grid;grid-template-columns:repeat(2,minmax(0,1fr));gap:14px}.field{display:flex;flex-direction:column;gap:6px}.field.full{grid-column:1/-1}.field label{font-size:12px;font-weight:700;color:var(--ink-soft)}
input,textarea,select{width:100%;border:1px solid var(--border);border-radius:10px;background:#fff;color:var(--ink);font:13.5px 'Inter',sans-serif;padding:10px 12px;outline:none;transition:.15s}textarea{min-height:96px;resize:vertical}input:focus,textarea:focus,select:focus{border-color:var(--blue);box-shadow:0 0 0 3px rgba(47,91,255,.09)}
.list{border:1px solid var(--border);border-radius:14px;overflow:hidden}.list-row{display:grid;grid-template-columns:minmax(0,1fr) auto;gap:12px;padding:14px 16px;border-bottom:1px solid var(--border-soft);align-items:center}.list-row:last-child{border-bottom:none}.list-row:hover{background:var(--paper-soft)}.card-front{font-weight:650;font-size:13.5px}.card-back{font-size:12.5px;color:var(--ink-soft);margin-top:4px;white-space:pre-line}
.review-wrap{max-width:760px;margin:0 auto}.review-card{min-height:280px;border:1px solid var(--border);border-radius:22px;box-shadow:var(--shadow-md);padding:30px;display:flex;flex-direction:column;justify-content:center;text-align:center;background:linear-gradient(180deg,#fff,#fbfcff)}.review-q{font-size:25px;line-height:1.35;font-weight:800}.review-a{margin-top:24px;padding-top:24px;border-top:1px solid var(--border);font-size:17px;line-height:1.7;color:var(--ink-soft);white-space:pre-line}.rating-row{display:grid;grid-template-columns:repeat(4,1fr);gap:8px;margin-top:14px}.rating-row .btn{padding:12px 8px}.rating-row small{display:block;font:10px 'IBM Plex Mono',monospace;margin-top:3px;opacity:.8}
.notice{border:1px solid #c8d4ff;background:var(--blue-soft);color:#2946a6;border-radius:12px;padding:12px 14px;font-size:12.5px;line-height:1.55}.notice.warn{border-color:#eed3a5;background:var(--amber-soft);color:#805810}.notice.error{border-color:#f3c4c1;background:var(--red-soft);color:#a43630}.notice.ok{border-color:#b8e8d2;background:var(--green-soft);color:#14724b}
.login-shell{max-width:520px;margin:0 auto;padding:80px 18px}.login-card{background:#fff;border:1px solid var(--border);border-radius:28px;padding:34px;box-shadow:var(--shadow-lg)}
.toast{position:fixed;bottom:22px;left:50%;transform:translateX(-50%);background:var(--ink);color:#fff;font:12.5px 'IBM Plex Mono',monospace;padding:10px 18px;border-radius:20px;box-shadow:0 10px 26px rgba(0,0,0,.25);opacity:0;pointer-events:none;transition:.25s;z-index:100}.toast.show{opacity:1;transform:translateX(-50%) translateY(-6px)}
.spinner{width:16px;height:16px;border:2px solid rgba(255,255,255,.35);border-top-color:#fff;border-radius:50%;display:inline-block;vertical-align:-3px;animation:spin .7s linear infinite}@keyframes spin{to{transform:rotate(360deg)}}
@media(max-width:680px){#app-shell{padding:16px 10px 60px}#app{padding:22px 18px 30px;border-radius:20px}h1{font-size:24px}.form-grid{grid-template-columns:1fr}.rating-row{grid-template-columns:1fr 1fr}.review-q{font-size:21px}.deck-grid{grid-template-columns:1fr}}

/* Exercices interactifs */
.exercise-progress{height:7px;background:var(--paper-alt);border-radius:999px;overflow:hidden;margin:0 0 14px}.exercise-progress>div{height:100%;background:linear-gradient(90deg,var(--blue),#7fa0ff);transition:width .2s}
.interactive-card{min-height:360px;justify-content:flex-start;padding-top:34px}.exercise-count{font:600 10.5px 'IBM Plex Mono',monospace;color:var(--muted);letter-spacing:.08em;margin-bottom:18px}.choice-grid{display:grid;grid-template-columns:repeat(auto-fit,minmax(140px,1fr));gap:12px;width:100%;max-width:560px;margin:28px auto 0}.choice-btn{min-height:54px;border:1px solid var(--border);background:var(--paper);border-radius:14px;font:800 16px 'Inter',sans-serif;color:var(--ink);cursor:pointer;transition:.15s;padding:12px 16px}.choice-btn:hover:not(:disabled){border-color:var(--blue);background:var(--blue-soft);color:var(--blue);transform:translateY(-1px)}.choice-btn:disabled{cursor:default}.choice-btn.correct{border-color:#8ed7b5;background:var(--green-soft);color:var(--green)}.choice-btn.wrong{border-color:#efaaa5;background:var(--red-soft);color:var(--red)}
.answer-feedback{width:100%;max-width:620px;margin:24px auto 0;padding:14px 16px;border-radius:14px;text-align:left;font-size:13.5px;line-height:1.55}.answer-feedback.correct{border:1px solid #b8e8d2;background:var(--green-soft);color:#14724b}.answer-feedback.wrong{border:1px solid #f3c4c1;background:var(--red-soft);color:#a43630}.answer-feedback p{margin:6px 0 0;color:inherit}.next-question{margin-top:18px;align-self:center}.exercise-summary .score-big{font-size:58px;font-weight:800;letter-spacing:-.04em;color:var(--blue);margin:8px 0}.exercise-summary p{max-width:520px;margin-left:auto;margin-right:auto}
@media(max-width:680px){.choice-grid{grid-template-columns:1fr 1fr}.interactive-card{min-height:320px}.exercise-summary .score-big{font-size:48px}}