/* Observatoire autonome. Les règles du défi intégré aux cours restent inchangées. */
.math-observatory-page {--ink:#173546;--muted:#4e6571;--paper:#faf9f5;--line:#d6e0df;--teal:#006963;--orange:#a74216;background:var(--paper);color:var(--ink);font-family:system-ui,-apple-system,BlinkMacSystemFont,"Segoe UI",sans-serif;margin:0;line-height:1.55}
.math-observatory-page * {box-sizing:border-box}
.math-observatory-page [hidden] {display:none!important}
.math-observatory-page a {color:var(--teal);text-underline-offset:3px}
.math-observatory-page button,.math-observatory-page input,.math-observatory-page select {font:inherit}
.math-observatory-page button,.math-observatory-page .obs-button {min-height:44px;border:1px solid #b3c6c7;border-radius:8px;background:white;color:var(--ink);padding:9px 14px;cursor:pointer;text-decoration:none;display:inline-flex;align-items:center;justify-content:center;gap:8px;font-weight:650}
.math-observatory-page button:hover,.math-observatory-page .obs-button:hover {background:#edf5f1;border-color:var(--teal)}
.math-observatory-page button:disabled {opacity:.6;cursor:default}
.math-observatory-page .obs-primary {background:var(--teal);color:white;border-color:var(--teal)}
.math-observatory-page .obs-primary:hover {background:#004e49;color:white}
.math-observatory-page :focus-visible {outline:3px solid #a74216;outline-offset:4px}
.obs-header {max-width:1420px;margin:auto;padding:20px 28px;display:flex;align-items:center;justify-content:space-between;gap:20px;border-bottom:1px solid var(--line)}
.obs-brand {display:flex;gap:10px;align-items:center;font-weight:750;text-decoration:none!important;color:var(--ink)!important;font-size:21px}
.obs-brand img {width:36px;height:36px;object-fit:contain}
.obs-header nav {display:flex;gap:24px;font-size:14px}
.obs-header nav a {color:var(--ink)}
.obs-hero {max-width:1420px;margin:auto;padding:28px 28px 26px;display:grid;grid-template-columns:1fr auto;gap:24px;align-items:center}
.obs-hero h1 {font-size:clamp(26px,3vw,42px);line-height:1.16;letter-spacing:-.035em;margin:6px 0 12px;font-weight:750;max-width:820px}
.obs-hero p {max-width:780px;margin:0;color:var(--muted)}
.obs-eyebrow {font-size:12px;font-weight:700;letter-spacing:.065em;color:var(--teal)!important;margin:0 0 8px}
.obs-hero aside {font-size:13px;border-left:2px solid #9bbfba;padding-left:18px;color:var(--muted);max-width:240px}
.obs-hero aside strong {color:var(--ink);display:block}
.math-observatory {max-width:1420px;margin:0 auto;padding:0 28px 42px}
.obs-shell {display:grid;grid-template-columns:244px minmax(0,1fr);gap:18px;align-items:start}
.obs-sidebar {background:#eef2ed;border:1px solid var(--line);border-radius:14px;padding:18px 12px;min-width:0;max-width:100%}
.obs-sidebar h2 {font-size:14px;margin:0 8px 12px}
.obs-sidebar [data-mode] {display:flex;align-items:center;justify-content:flex-start;gap:10px;text-align:left;width:100%;border:1px solid transparent;background:transparent;padding:12px 10px;font-size:14px;border-radius:8px;margin-bottom:4px;line-height:1.35}
.obs-sidebar [data-mode][aria-pressed=true] {background:#fff;border-color:#9ebfba;box-shadow:0 2px 6px #1735460a;color:#005d57}
.obs-mode-number {font-size:12px;color:#4e6571;min-width:20px;font-variant-numeric:tabular-nums}
.obs-sidebar [data-mode][aria-pressed=true] .obs-mode-number {color:#006963}
.obs-sidebar .obs-local {border-top:1px solid #cedbd4;margin:18px 8px 0;padding-top:15px;font-size:12px;color:var(--muted)}
.obs-workspace {min-width:0}
.obs-topline {display:flex;justify-content:space-between;gap:16px;align-items:start;margin:0 0 14px}
.obs-topline h2 {font-size:23px;letter-spacing:-.025em;line-height:1.25;margin:0 0 5px}
.obs-topline p {margin:0;font-size:14px;color:var(--muted);max-width:680px}
.obs-tools {display:flex;gap:8px;flex-wrap:wrap;align-items:center;margin:12px 0}
.obs-tools button,.obs-tools .obs-button {font-size:13px;padding:8px 12px}
.obs-instruments {display:grid;grid-template-columns:minmax(0,1fr) 240px;gap:14px;align-items:start}
.obs-instruments--single {grid-template-columns:minmax(0,1fr)}
.obs-instruments--single .obs-graph {max-width:820px}
.obs-sign-variation {font-size:14px;margin-top:12px}
.obs-card {border:1px solid var(--line);background:white;border-radius:12px;padding:18px;min-width:0;overflow-wrap:anywhere}
.obs-graph {padding:0;overflow:hidden;background:#fcfdfb}
.obs-graph-head {padding:14px 18px 0;display:flex;justify-content:space-between;gap:8px;align-items:center;font-size:13px}
.obs-graph svg {display:block;width:100%;height:auto;aspect-ratio:720/440;touch-action:pan-y}
.obs-graph svg text {font-family:system-ui,sans-serif;font-size:16px;fill:#435d69}
.obs-graph .obs-curve {stroke:#006963;stroke-width:3;fill:none;vector-effect:non-scaling-stroke}
.obs-graph .obs-compare {stroke:#a74216;stroke-width:2.5;stroke-dasharray:7 5;fill:none;vector-effect:non-scaling-stroke}
.obs-graph .obs-axis {stroke:#91a7ae;stroke-width:1.2}
.obs-graph .obs-grid {stroke:#e1e9e4;stroke-width:1}
.obs-graph .obs-symmetry {stroke:#61968e;stroke-width:1.5;stroke-dasharray:4 5}
.obs-graph [data-drag-vertex] {cursor:grab;touch-action:none}
.obs-graph-caption {margin:0;padding:0 18px 15px;color:var(--muted);font-size:12px}
.obs-controls h3 {font-size:14px;margin:0 0 14px}
.obs-parameter {margin:0 0 20px}
.obs-parameter label {display:flex;justify-content:space-between;gap:12px;font-size:13px;font-weight:650;align-items:center}
.obs-parameter input[type=number] {width:82px;padding:6px;border:1px solid #8aa6aa;border-radius:5px;min-height:38px;color:var(--ink);background:white}
.obs-parameter input[type=range] {width:100%;accent-color:var(--teal);margin:12px 0 0;min-height:25px}
.obs-controls small {font-size:12px;color:var(--muted)}
.obs-controls .obs-preset {font-size:12px;min-height:36px;padding:6px 9px}
.obs-formulas {display:grid;grid-template-columns:repeat(3,minmax(0,1fr));gap:12px;margin:14px 0}
.obs-formulas h3 {font-size:12px;color:var(--muted);font-weight:650;margin:0 0 9px}
.obs-formula {font-family:Georgia,"Times New Roman",serif;font-size:19px;overflow-wrap:anywhere;line-height:1.65;margin:0}
.obs-formulas small {display:block;font-size:11px;line-height:1.5;color:var(--muted);margin-top:6px}
.obs-readouts {display:grid;grid-template-columns:1fr 1fr;gap:12px;margin:14px 0}
.obs-readouts h3 {font-size:14px;margin:0 0 10px}
.obs-readouts p {font-size:14px;margin:8px 0}
.obs-metrics {display:flex;gap:18px;flex-wrap:wrap;font-size:13px;padding-bottom:8px;border-bottom:1px solid var(--line)}
.obs-metrics strong {display:block;color:var(--ink);font-size:17px}
.obs-values {overflow:auto}
.obs-values table {width:100%;border-collapse:collapse;font-size:13px;text-align:center}
.obs-values th,.obs-values td {padding:8px 9px;border-bottom:1px solid #e6edeb;white-space:nowrap}
.obs-values th {background:#eff5f1;font-weight:650}
.obs-probe {display:flex;gap:10px;align-items:center;flex-wrap:wrap;font-size:13px}
.obs-probe input {width:100px;min-height:40px;border:1px solid #8aa6aa;border-radius:5px;padding:6px}
.obs-tabs {display:flex;gap:6px;flex-wrap:wrap;margin:14px 0 0}
.obs-tabs button {font-size:13px;min-height:38px}
.obs-tabs [aria-pressed=true] {background:#e9f4ee;border-color:var(--teal);color:#005d57}
.obs-feedback {padding:10px 14px;border-left:3px solid #a74216;background:#fff5eb;font-size:14px;border-radius:4px;margin:12px 0}
.obs-feedback[data-success=true] {border-color:#006963;background:#eaf5ee}
.obs-step {margin:14px 0;border:1px solid #b8cdc6;background:#f4f8f2;border-radius:12px;padding:20px}
.obs-step h3 {font-size:17px;margin:0 0 8px}
.obs-step p {margin:8px 0 14px}
.obs-step fieldset {border:0;padding:0;margin:15px 0;min-width:0}
.obs-step legend {font-size:14px;font-weight:650;margin-bottom:8px}
.obs-choice {display:flex;align-items:baseline;gap:10px;font-size:14px;margin:8px 0;cursor:pointer}
.obs-choice input {accent-color:var(--teal);width:18px;min-width:18px;height:18px;position:relative;top:3px}
.obs-answer-grid {display:flex;flex-wrap:wrap;gap:12px;margin:14px 0}
.obs-answer-grid label {display:flex;flex-direction:column;gap:5px;font-size:13px;flex:1 1 170px}
.obs-answer-grid input {width:100%;max-width:220px;padding:9px;border:1px solid #8aa6aa;border-radius:6px;min-height:44px;background:white;color:var(--ink)}
.obs-proof {background:white;border:1px solid var(--line);padding:14px;border-radius:8px;font-size:14px}
.obs-proof summary {cursor:pointer;min-height:36px;font-weight:650}
.obs-notebook {margin:22px 0 0}
.obs-notebook h2 {font-size:22px;margin-bottom:5px}
.obs-notebook p {color:var(--muted);font-size:14px}
.obs-snapshots {display:grid;grid-template-columns:repeat(3,minmax(0,1fr));gap:12px}
.obs-snapshot {border:1px solid var(--line);background:white;border-radius:10px;padding:15px;min-width:0}
.obs-snapshot h3 {font-size:14px;margin:0 0 8px}
.obs-snapshot p {font-size:14px}
.obs-snapshot button {font-size:12px;padding:7px;min-height:38px}
.obs-empty {border:1px dashed #97b6b1;background:#f2f6f0;padding:20px;border-radius:10px}
.obs-progress {font-size:13px;padding:12px 0;border-top:1px solid var(--line);margin:16px 0}
.obs-progress ul {display:flex;gap:8px;flex-wrap:wrap;list-style:none;margin:10px 0;padding:0}
.obs-progress li {padding:6px 10px;border-radius:6px;background:#edf5ee}
.obs-bottom {max-width:1364px;margin:0 auto 40px;padding:0 28px}
.obs-reading {border-top:1px solid var(--line);padding:24px 0;margin-top:22px}
.obs-reading h2 {font-size:23px}
.obs-reading-grid {display:grid;grid-template-columns:repeat(3,minmax(0,1fr));gap:22px}
.obs-reading-grid h3 {font-size:16px;margin:0 0 8px}
.obs-reading-grid p {font-size:14px;color:var(--muted)}
.obs-source {font-size:13px;color:var(--muted)}
.obs-source li {margin:8px 0}
.obs-dialog {max-width:min(520px,90vw);border:1px solid #8aa6aa;border-radius:12px;padding:24px;background:white;color:var(--ink)}
.obs-dialog::backdrop {background:#10273988}
.obs-dialog input[type=text] {display:block;width:100%;min-height:44px;margin-top:8px;border:1px solid #8aa6aa;border-radius:6px;padding:8px}
.math-observatory:not([data-ready=true]) .obs-notebook button {display:none}
.obs-status {font-size:13px;color:var(--muted);margin:10px 0}
.math-observatory-page .math-lab-course-link {margin-top:20px}
.math-observatory-page .math-lab-footer {max-width:1420px;margin:auto}
@media(min-width:1200px) {.obs-sidebar {position:sticky;top:16px}}
@media(max-width:1100px) {.obs-instruments {grid-template-columns:minmax(0,1fr)}.obs-controls {display:grid;grid-template-columns:repeat(3,minmax(0,1fr));gap:14px}.obs-controls h3,.obs-controls>small,.obs-controls .obs-tools {grid-column:1/-1}.obs-parameter {margin:0}.obs-snapshots {grid-template-columns:repeat(2,minmax(0,1fr))}.obs-formulas {grid-template-columns:1fr}.obs-formulas .obs-card {padding:12px 16px}.obs-formulas h3 {margin-bottom:3px}}
@media(max-width:780px) {.obs-header {padding:16px}.obs-header nav {gap:14px;font-size:12px}.obs-header nav a:last-child {display:none}.obs-hero {padding:24px 16px;grid-template-columns:1fr;gap:12px}.obs-hero aside {max-width:none;border-left:0;padding:0}.obs-hero aside strong {display:inline}.obs-shell {grid-template-columns:1fr}.math-observatory {padding:0 16px 30px}.obs-sidebar {padding:10px}.obs-sidebar h2 {margin:4px 6px 9px}.obs-mode-list {display:flex;overflow-x:auto;gap:5px;padding:2px 3px 8px}.obs-sidebar [data-mode] {white-space:nowrap;width:auto;min-width:max-content;padding:10px}.obs-sidebar .obs-local {display:none}.obs-readouts {grid-template-columns:1fr}.obs-reading-grid {grid-template-columns:1fr}.obs-bottom {padding:0 16px}.obs-graph svg text {font-size:20px}.obs-topline h2 {font-size:22px}}
@media(max-width:600px) {.obs-graph svg {aspect-ratio:480/340}.obs-graph svg text {font-size:23px}}
@media(max-width:420px) {.obs-header nav {gap:10px}.obs-brand {font-size:18px}.obs-brand img {width:30px;height:30px}.obs-controls {grid-template-columns:1fr}.obs-parameter label {font-size:14px}.obs-parameter input[type=number] {min-height:44px;width:100px}.obs-parameter input[type=range] {min-height:30px}.obs-snapshots {grid-template-columns:1fr}.obs-step {padding:16px}.obs-card {padding:14px}.obs-graph {padding:0}.obs-formula {font-size:18px}.obs-graph-head {padding:12px}.obs-topline {display:block}.obs-graph svg {min-height:235px}}
@media(forced-colors:active) {.obs-curve,.obs-compare,.obs-axis,.obs-symmetry {stroke:CanvasText!important}.obs-grid {stroke:GrayText!important}.obs-graph svg text {fill:CanvasText!important}.obs-graph circle {fill:CanvasText!important}.obs-sidebar [aria-pressed=true],.obs-tabs [aria-pressed=true] {border:2px solid Highlight!important}.obs-parameter input[type=range] {forced-color-adjust:auto}}