:root {
  color-scheme: light;
  --bg: #f7f8fa;
  --panel: #ffffff;
  --text: #202733;
  --muted: #687385;
  --border: #e5e8ee;
  --accent: #4f46e5;
  --accent-hover: #4338ca;
  --accent-soft: #eeedfc;
  --success: #23704b;
  --error: #b43f47;
  --mono: "SFMono-Regular", Consolas, "Liberation Mono", monospace;
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", sans-serif;
  font-size: 14px;
  -webkit-font-smoothing: antialiased;
  --surface: #fafbfc;
  --sidebar: #fbfcfd;
  --hover: #f1f3f7;
  --subtle: #f2f4f7;
  --border-hover: #c2c7d2;
  --strong: #485367;
  --faint: #7a8596;
  --accent-text: #433ac3;
  --accent-muted: #7971b7;
  --accent-border: #dfdcfa;
  --success-soft: #edf7f0;
  --warning: #926a1e;
  --warning-soft: #fbf4e5;
  --error-soft: #fceff0;
  --syntax-comment: #677587;
  --syntax-keyword: #6f37b4;
  --syntax-string: #23704b;
  --syntax-function: #215dc0;
  --syntax-number: #a15417;
  --syntax-operator: #465269;
  --selection: #cddafa;

}
:root[data-theme="dark"] {
  color-scheme: dark;
  --bg: #11151e;
  --panel: #1a202c;
  --surface: #161c27;
  --sidebar: #151b25;
  --hover: #252e3e;
  --subtle: #252d3b;
  --text: #e6eaf2;
  --strong: #d1d9e8;
  --muted: #a7b3c6;
  --faint: #96a4ba;
  --border: #303a4d;
  --border-hover: #596781;
  --accent: #aaa2ff;
  --accent-hover: #c1baff;
  --accent-soft: #2c294b;
  --accent-text: #c1baff;
  --accent-muted: #b2acd8;
  --accent-border: #454068;
  --success: #80d4aa;
  --success-soft: #203a30;
  --warning: #edc477;
  --warning-soft: #3b3222;
  --error: #f49a9f;
  --error-soft: #41272e;
  --syntax-comment: #96a4ba;
  --syntax-keyword: #c4a1ff;
  --syntax-string: #8fd4aa;
  --syntax-function: #91c2ff;
  --syntax-number: #edc477;
  --syntax-operator: #ced7e7;
  --selection: #354d73;
}

* { box-sizing: border-box; }
body { margin: 0; background: var(--bg); color: var(--text); }
button, input, select, textarea { font: inherit; }
button, a, input, select, textarea, summary { -webkit-tap-highlight-color: transparent; }
button { cursor: pointer; }
button:disabled { cursor: default; opacity: .55; }
button, .signin-link {
  min-height: 38px;
  border: 1px solid transparent;
  border-radius: 7px;
  padding: 8px 13px;
  font-size: 13px;
  font-weight: 550;
  line-height: 20px;
  white-space: nowrap;
  transition: background-color .15s, border-color .15s, color .15s;
}
button:focus-visible, a:focus-visible, summary:focus-visible { outline: 3px solid #a7a3f2; outline-offset: 3px; }
button svg, .panel-heading > svg, .search-field svg {
  width: 18px; height: 18px; flex-shrink: 0; fill: none; stroke: currentColor;
  stroke-width: 1.5; stroke-linecap: round; stroke-linejoin: round;
}
.primary { background: var(--accent); border-color: var(--accent); color: var(--panel); display: inline-flex; align-items: center; justify-content: center; gap: 7px; }
.primary:hover:not(:disabled) { background: var(--accent-hover); border-color: var(--accent-hover); }
.secondary { background: var(--panel); border-color: var(--border); color: var(--strong); display: inline-flex; align-items: center; justify-content: center; gap: 7px; }
.secondary:hover:not(:disabled) { background: var(--hover); border-color: var(--border-hover); }
.text-button { background: transparent; color: var(--muted); }
.text-button:hover:not(:disabled) { background: var(--hover); color: var(--text); }
.icon-button { display: inline-flex; align-items: center; justify-content: center; padding: 8px; color: var(--muted); background: transparent; }
.icon-button:hover { background: var(--hover); }
.small { font-size: 12px; line-height: 1.65; color: var(--muted); }
.section-label { font-size: 11px; font-weight: 650; letter-spacing: 1.1px; color: var(--muted); }
p { line-height: 1.7; }
h1, h2, h3, p { margin-top: 0; }
[hidden] { display: none !important; }
.sr-only { position: absolute; width: 1px; height: 1px; padding: 0; overflow: hidden; clip: rect(0, 0, 0, 0); white-space: nowrap; border: 0; }
.skip-link { position: fixed; z-index: 10; top: -60px; left: 16px; background: var(--panel); color: var(--accent); padding: 12px; border-radius: 6px; }
.skip-link:focus { top: 12px; }

.topbar { height: 68px; display: flex; align-items: center; gap: 28px; padding: 0 28px; background: var(--panel); border-bottom: 1px solid var(--border); }
.brand { display: flex; align-items: center; gap: 11px; color: var(--text); text-decoration: none; font-size: 17px; font-weight: 700; letter-spacing: -.5px; white-space: nowrap; }
.brand-light { font-weight: 450; }
.brand-mark { width: 33px; height: 33px; border-radius: 8px; display: grid; place-items: center; background: #292742; color: #fff; font: 650 15px var(--mono); letter-spacing: -2px; padding-right: 2px; }
.topbar-context { display: flex; align-items: center; gap: 24px; color: var(--muted); font-size: 12px; }
.context-divider { height: 20px; width: 1px; background: var(--border); }
.status-pill { display: inline-flex; align-items: center; gap: 7px; margin-left: auto; border: 1px solid var(--border); border-radius: 6px; padding: 5px 9px; font-size: 11px; color: var(--muted); white-space: nowrap; }
.status-pill::before { content: ""; width: 6px; height: 6px; border-radius: 50%; background: #909baa; }
.status-pill[data-mode="ai"]::before { background: #329264; }

.app-shell { display: grid; grid-template-columns: 232px minmax(0, 1fr); min-height: calc(100dvh - 68px); }
.sidebar { background: var(--sidebar); border-right: 1px solid var(--border); padding: 28px 16px 20px; display: flex; flex-direction: column; min-width: 0; }
.sidebar-heading { display: flex; align-items: center; gap: 8px; padding: 0 7px; margin-bottom: 18px; }
.sidebar-heading .section-label { font-size: 12px; letter-spacing: 0; font-weight: 600; color: var(--strong); }
.count { padding: 1px 6px; background: var(--subtle); border-radius: 4px; font-size: 10px; color: var(--muted); font-variant-numeric: tabular-nums; }
.search-field { display: flex; align-items: center; gap: 7px; border: 1px solid var(--border); border-radius: 6px; background: var(--panel); padding-left: 9px; color: var(--faint); }
.search-field:focus-within { border-color: #a7a3f2; box-shadow: 0 0 0 2px var(--accent-soft); }
.search-field svg { width: 15px; height: 15px; }
.search-field input { min-width: 0; width: 100%; border: none; background: transparent; padding: 9px 6px 9px 0; font-size: 12px; box-shadow: none; }
.search-field input:focus { box-shadow: none; }
.library-list { display: grid; grid-auto-rows: max-content; scrollbar-gutter: stable; align-content: start; gap: 5px; margin-top: 18px; max-height: 480px; overflow-y: auto; }
.library-item { width: 100%; min-width: 0; display: block; position: relative; text-align: left; white-space: normal; background: transparent; color: var(--strong); padding: 12px 11px; font-weight: 500; }
.library-item:hover { background: var(--hover); }
.library-item.active { color: var(--accent-text); background: var(--accent-soft); }
.library-item-title { display: block; font-size: 12px; line-height: 1.5; overflow-wrap: anywhere; }
.library-item small { display: flex; align-items: flex-start; line-height: 1.5; gap: 6px; font-size: 10px; font-weight: 400; color: var(--faint); margin-top: 5px; }
.library-item.active small { color: var(--accent-muted); }
.difficulty-dot { flex-shrink: 0; margin-top: 5px; width: 5px; height: 5px; border-radius: 50%; display: inline-block; background: #47946e; }
.difficulty-dot[data-difficulty="Medium"] { background: #b58731; }
.difficulty-dot[data-difficulty="Hard"] { background: #b43f47; }
.empty-library { color: var(--muted); font-size: 12px; padding: 12px; }
.library-actions { display: grid; gap: 4px; border-top: 1px solid var(--border); padding-top: 20px; margin-top: 24px; }
.import-button { font-size: 11px; padding-left: 8px; padding-right: 8px; }
.library-actions .text-button { font-size: 11px; }
.shared-controls { display: grid; gap: 6px; margin-top: 24px; padding-top: 20px; border-top: 1px solid var(--border); }
.shared-controls .text-button { text-align: left; white-space: normal; padding: 5px 8px; font-size: 11px; }
.shared-controls .section-label { margin: 0 8px 8px; }
.signin-link { text-decoration: none; text-align: center; white-space: normal; font-size: 11px; }
.sidebar-footer { display: flex; align-items: flex-start; gap: 8px; margin-top: auto; padding: 32px 8px 0; }
.local-indicator { width: 6px; height: 6px; border-radius: 50%; background: #60947c; flex-shrink: 0; }
.sidebar-footer .local-indicator { margin-top: 5px; }
.sidebar-footer strong, .sidebar-footer div > span { display: block; font-size: 10px; line-height: 1.7; }
.sidebar-footer strong { color: var(--muted); font-weight: 500; }
.sidebar-footer div > span { color: var(--faint); }
.library-open, .library-close { display: none; }

main { width: 100%; max-width: 1580px; margin: 0 auto; padding: 30px 32px 0; min-width: 0; }
.workspace-heading { display: flex; align-items: center; justify-content: space-between; gap: 20px; margin-bottom: 27px; }
.workspace-heading .section-label { font-size: 10px; letter-spacing: 1.3px; }
.workspace-heading h1 { font-size: 26px; line-height: 1.3; font-weight: 650; letter-spacing: -.8px; margin: 8px 0 5px; }
.workspace-heading p { font-size: 12px; color: var(--muted); margin-bottom: 0; }
.workspace-actions { display: flex; align-items: center; gap: 8px; }
.workspace { display: grid; grid-template-columns: minmax(0, 1fr) minmax(0, 1.15fr); gap: 20px; align-items: start; }
.panel { min-width: 0; background: var(--panel); border: 1px solid var(--border); border-radius: 10px; overflow: hidden; box-shadow: 0 2px 4px #20273303; }
.panel-heading { min-height: 51px; padding: 0 20px; display: flex; align-items: center; gap: 8px; border-bottom: 1px solid var(--border); color: var(--strong); font-size: 12px; font-weight: 550; }
.panel-heading > svg { width: 16px; height: 16px; color: var(--faint); }
.panel-note { margin-left: auto; font-size: 10px; font-weight: 400; color: var(--faint); white-space: nowrap; }
.problem { grid-column: 1; grid-row: 1 / span 2; }
.problem-body { padding: 26px 26px 20px; }
.question-meta { display: flex; align-items: center; gap: 7px; margin-bottom: 14px; }
.difficulty-pill, .topic-pill { font-size: 10px; font-weight: 500; padding: 4px 8px; border-radius: 5px; line-height: 1.3; }
.difficulty-pill { color: var(--success); background: var(--success-soft); }
.difficulty-pill[data-difficulty="Medium"] { color: var(--warning); background: var(--warning-soft); }
.difficulty-pill[data-difficulty="Hard"] { color: var(--error); background: var(--error-soft); }
.topic-pill { color: var(--muted); background: var(--subtle); }
.problem h2 { font-size: 25px; font-weight: 650; letter-spacing: -.7px; margin-bottom: 18px; line-height: 1.3; overflow-wrap: anywhere; }
.description { font-size: 13px; line-height: 1.85; color: var(--muted); margin-bottom: 28px; overflow-wrap: anywhere; }
.problem h3 { font-size: 12px; font-weight: 650; margin: 24px 0 11px; }
.example, .test-case { border: 1px solid var(--border); border-radius: 7px; background: var(--surface); padding: 15px; }
.example strong, .test-case strong { display: block; font-size: 11px; color: var(--muted); font-weight: 500; margin-bottom: 13px; }
.test-value { display: flex; align-items: baseline; gap: 12px; font: 11px/1.8 var(--mono); }
.test-value + .test-value { margin-top: 4px; }
.test-value span { flex: 0 0 55px; color: var(--faint); font-family: inherit; }
.test-value code { color: var(--strong); overflow-wrap: anywhere; min-width: 0; }
.constraints { padding-left: 17px; margin: 0; }
.constraints li { padding-left: 3px; margin-bottom: 9px; font-size: 12px; color: var(--muted); line-height: 1.65; }
.constraints li::marker { color: #a0a9b7; font-size: 10px; }
.test-details { border-top: 1px solid var(--border); margin-top: 25px; }
.test-details summary { display: flex; align-items: center; justify-content: space-between; list-style: none; cursor: pointer; padding-top: 18px; color: var(--muted); font-size: 11px; font-weight: 550; }
.test-details summary::-webkit-details-marker { display: none; }
.chevron { border: solid var(--faint); border-width: 0 1.5px 1.5px 0; padding: 3px; transform: rotate(45deg); margin-right: 3px; }
details[open] .chevron { transform: rotate(225deg); }
.test-case { margin-top: 10px; }
.source-note { font-size: 10px; line-height: 1.6; color: var(--faint); margin: 25px 0 0; }
.problem-footer { display: flex; align-items: center; flex-wrap: wrap; gap: 7px; border-top: 1px solid var(--border); padding: 13px 24px; font-size: 10px; color: var(--faint); }
.footer-separator { color: #b7bec8; }

.coding { grid-column: 2; grid-row: 1; }
.editor-toolbar h2 { margin: 0; font-size: 12px; font-weight: 550; }
.language-pill { background: var(--subtle); color: var(--muted); border-radius: 4px; padding: 2px 6px; font-size: 10px; font-weight: 400; }
.language-picker { width: auto; max-width: 125px; background: var(--subtle); color: var(--muted); border: 1px solid var(--border); border-radius: 5px; padding: 4px 6px; font-size: 11px; margin-left: auto; }
.language-picker:disabled { opacity: 1; color: var(--muted); }
.editor-toolbar #reset { margin-left: 0; }
.compiler-diagnostics { margin: 14px 20px; color: var(--muted); font-size: 11px; }
.compiler-diagnostics pre { max-height: 180px; overflow: auto; white-space: pre-wrap; overflow-wrap: anywhere; font: 11px/1.6 var(--mono); color: var(--text); }
.editor-toolbar .text-button { margin-left: auto; font-size: 10px; min-height: 30px; padding: 4px 7px; }
.editor-file { display: flex; align-items: center; gap: 7px; padding: 12px 20px; background: var(--surface); border-bottom: 1px solid var(--subtle); font-size: 11px; color: var(--muted); }
.file-mark { font-size: 9px; font-weight: 650; color: var(--warning); background: var(--warning-soft); border-radius: 3px; padding: 2px 3px; line-height: 1; }
.editor-saved { margin-left: auto; font-size: 9px; color: var(--faint); }
.code-editor { display: flex; height: 330px; min-height: 220px; background: var(--panel); overflow: hidden; }
.line-numbers, .code, .code-highlight { font: 13px/24px var(--mono); padding-top: 20px; padding-bottom: 20px; margin: 0; tab-size: 2; }
.line-numbers { flex: 0 0 48px; padding-left: 12px; padding-right: 12px; overflow: hidden; user-select: none; text-align: right; color: var(--faint); background: var(--surface); }
.code { position: relative; height: 100%; min-width: 0; width: 100%; border: 0; border-radius: 0; padding-left: 12px; padding-right: 20px; background: transparent; resize: none; color: transparent; -webkit-text-fill-color: transparent; caret-color: var(--text); outline: none; }
.code:focus { box-shadow: inset 0 0 0 2px #b4b0f455; }
.run-bar { display: flex; align-items: center; justify-content: space-between; gap: 12px; padding: 12px 18px; background: var(--surface); border-top: 1px solid var(--border); border-bottom: 1px solid var(--border); }
.run-bar .primary { min-width: 97px; min-height: 34px; font-size: 11px; padding-top: 6px; padding-bottom: 6px; }
.shortcut { display: flex; align-items: center; gap: 4px; font-size: 10px; color: var(--faint); }
.shortcut > span { margin-left: 4px; }
kbd { font-family: inherit; font-size: 9px; line-height: 16px; border: 1px solid var(--border); border-radius: 4px; padding: 0 4px; background: var(--panel); color: var(--faint); }
.results-heading { display: flex; align-items: center; gap: 12px; padding: 17px 20px 0; }
.results-heading h3 { margin: 0; font-size: 11px; font-weight: 600; }
.results { padding: 20px; max-height: 270px; overflow: auto; min-height: 125px; }
.results-empty { display: flex; align-items: center; gap: 12px; min-height: 64px; }
.results-empty-mark { flex: 0 0 32px; height: 32px; display: grid; place-items: center; border-radius: 8px; background: var(--hover); color: var(--faint); font: 12px var(--mono); }
.results-empty strong { display: block; font-size: 11px; color: var(--muted); font-weight: 500; margin-bottom: 3px; }
.results-empty p { font-size: 10px; color: var(--faint); margin: 0; line-height: 1.6; }
.results h3 { margin: 0 0 12px; font-size: 12px; }
.result { border-top: 1px solid var(--border); padding: 12px 0; font-size: 11px; }
.result:last-child { padding-bottom: 0; }
.result-heading { display: flex; align-items: center; justify-content: space-between; gap: 10px; }
.pass { color: var(--success); }
.fail { color: var(--error); }
.result pre { white-space: pre-wrap; overflow-wrap: anywhere; padding: 9px; border-radius: 5px; background: var(--surface); color: var(--muted); font: 10px/1.7 var(--mono); margin: 8px 0 0; }
.runner-note { padding: 0 20px; margin: 0 0 15px; color: var(--faint); font-size: 9px; line-height: 1.6; }

.coach { grid-column: 2; grid-row: 2; padding: 20px; }
.coach-heading, .coach-heading > div { display: flex; align-items: center; gap: 8px; }
.coach-heading { justify-content: space-between; }
.coach-heading h2 { font-size: 13px; font-weight: 600; margin: 0; letter-spacing: -.2px; }
.coach-mark { color: var(--accent-muted); font-size: 19px; }
.coach-heading .secondary { min-height: 30px; font-size: 10px; padding: 4px 9px; }
#coach-detail { font-size: 11px; color: var(--faint); margin: 6px 0 0; }
.messages { max-height: 260px; overflow: auto; }
.messages:empty { display: none; }
.messages:not(:empty) { margin-top: 18px; }
.message { background: var(--accent-soft); border: 1px solid var(--accent-border); border-radius: 7px; padding: 12px; margin-bottom: 10px; font-size: 12px; white-space: pre-wrap; overflow-wrap: anywhere; line-height: 1.75; color: var(--muted); }
.message.user { background: var(--surface); border-color: var(--border); color: var(--muted); }
#coach-form { display: flex; gap: 7px; margin-top: 17px; }
#coach-form input { min-width: 0; flex: 1; font-size: 11px; padding: 9px 11px; }
#coach-send { font-size: 10px; padding: 8px 10px; }
#coach-mode { font-size: 9px; margin: 8px 0 0; color: var(--faint); }
footer { display: flex; align-items: center; justify-content: space-between; gap: 15px; padding: 22px 2px; font-size: 10px; color: var(--faint); }
footer > span:first-child { color: var(--faint); }

input, select, textarea { background: var(--panel); border: 1px solid var(--border); color: var(--text); border-radius: 6px; padding: 10px 12px; outline: none; }
input::placeholder, textarea::placeholder { color: var(--faint); }
input:focus, select:focus, textarea:focus { border-color: #a7a3f2; box-shadow: 0 0 0 2px var(--accent-soft); }
label { display: block; font-size: 12px; font-weight: 500; color: var(--muted); margin-bottom: 8px; }
textarea { display: block; width: 100%; resize: vertical; line-height: 1.7; }
#notice { border: 1px solid var(--accent-border); background: var(--accent-soft); color: var(--accent-text); padding: 12px 15px; font-size: 12px; line-height: 1.65; border-radius: 7px; margin-bottom: 18px; overflow-wrap: anywhere; }
.workspace-tabs { display: none; }
.question-context { font-size: 12px; font-weight: 500; line-height: 1.6; color: var(--muted); margin: 0 2px 15px; overflow-wrap: anywhere; }

dialog { color: var(--text); border: 1px solid var(--border); background: var(--panel); border-radius: 13px; padding: 28px; width: min(560px, calc(100% - 32px)); max-height: calc(100dvh - 40px); box-shadow: 0 24px 80px #16223826; overflow: auto; }
dialog::backdrop { background: #1d263d55; backdrop-filter: blur(3px); }
.dialog-heading { display: flex; align-items: flex-start; justify-content: space-between; gap: 14px; }
.dialog-heading h2 { font-size: 21px; line-height: 1.35; font-weight: 650; letter-spacing: -.5px; margin: 7px 0 14px; }
.dialog-heading .section-label { font-size: 9px; }
.dialog-heading .icon-button { margin: -7px -7px 0 0; }
dialog > p { font-size: 12px; color: var(--muted); margin-bottom: 22px; }
.form-row { display: grid; grid-template-columns: 1fr 1fr; gap: 14px; margin-top: 18px; }
.form-row select { width: 100%; }
.form-help { font-size: 11px; color: var(--faint); margin: 14px 0 0; }
.dialog-actions { display: flex; justify-content: flex-end; gap: 10px; margin-top: 24px; padding-top: 18px; border-top: 1px solid var(--border); }
.import-label { margin-top: 22px; }
#question-json { font: 11px/1.7 var(--mono); }
#import-error, .form-error { color: var(--error); font-size: 12px; margin: 12px 0 0; }
.library-dialog { width: min(350px, calc(100% - 32px)); padding: 0; }
.library-dialog .sidebar { border: none; min-height: 500px; padding-top: 20px; }
.library-dialog .library-close { display: inline-flex; margin-left: auto; }
.library-dialog .sidebar-heading { margin-bottom: 13px; }
.library-dialog .library-list { max-height: 35dvh; }

@media (min-width: 1600px) {
  main { padding-top: 40px; padding-left: 44px; padding-right: 44px; }
  .workspace { gap: 24px; }
  .problem-body { padding: 32px; }
  .code-editor { height: 370px; }
}
@media (max-width: 1250px) {
  .app-shell { grid-template-columns: 214px minmax(0, 1fr); }
  main { padding-left: 22px; padding-right: 22px; }
  .workspace { gap: 16px; }
  .problem-body { padding: 22px; }
  .workspace-heading h1 { font-size: 24px; }
}
@media (max-width: 1100px) {
  .app-shell { display: block; }
  .library-open { display: inline-flex; }
  main { max-width: 1050px; padding: 28px 28px 0; }
}
@media (max-width: 760px) {
  .topbar { height: 60px; padding: 0 20px; gap: 12px; }
  .topbar-context { display: none; }
  .brand { font-size: 16px; }
  .brand-mark { width: 30px; height: 30px; font-size: 14px; }
  main { padding: 26px 20px 0; }
  .workspace-heading { align-items: flex-start; flex-wrap: wrap; gap: 17px; margin-bottom: 22px; }
  .workspace-heading h1 { font-size: 25px; }
  .workspace-actions { width: 100%; }
  .workspace-actions .primary { margin-left: auto; }
  .workspace-tabs { display: flex; gap: 20px; border-bottom: 1px solid var(--border); margin-bottom: 18px; }
  .workspace-tabs button { position: relative; color: var(--faint); background: transparent; font-size: 12px; padding: 10px 2px 12px; border-radius: 0; }
  .workspace-tabs button[aria-selected="true"] { color: var(--accent); }
  .workspace-tabs button[aria-selected="true"]::after { content: ""; position: absolute; left: 0; right: 0; bottom: -1px; height: 2px; background: var(--accent); }
  .workspace { display: block; }
  .problem-body { padding: 24px; }
  .problem h2 { font-size: 25px; }
  .code-editor { height: 350px; }
  .coach { padding: 24px; }
  .coach-heading h2 { font-size: 15px; }
  .coach-heading .secondary { font-size: 11px; }
  #coach-detail { font-size: 12px; }
  #coach-form { margin-top: 24px; }
  #coach-form input { font-size: 12px; }
  #coach-mode { font-size: 10px; }
  footer { padding-top: 20px; font-size: 9px; }
}
@media (max-width: 400px) {
  .topbar { padding: 0 16px; }
  .brand { font-size: 14px; gap: 8px; }
  .status-pill { font-size: 10px; padding: 4px 7px; }
  main { padding: 24px 16px 0; }
  .problem-body { padding: 20px; }
  .panel-heading { padding-left: 16px; padding-right: 16px; }
  .coach { padding: 20px; }
  #coach-form { flex-wrap: wrap; }
  #coach-form input { flex-basis: 100%; }
  #coach-send { margin-left: auto; }
  footer > span:last-child { display: none; }
  dialog { padding: 22px; }
}
@media (prefers-reduced-motion: reduce) {
  *, *::before, *::after { transition: none !important; }
}
.consent-page { width: min(100% - 40px, 620px); margin: 80px auto; padding: 32px; background: var(--panel); border: 1px solid var(--border); border-radius: 16px; }
.consent-page h1 { font-size: 24px; line-height: 1.3; margin-bottom: 24px; }
.consent-page p { line-height: 1.6; margin: 16px 0; }
.consent-page form { margin-top: 24px; }
.consent-page input[type="checkbox"] { width: auto; margin-right: 8px; }

.topnav { display: flex; gap: 4px; }
.topnav button { background: transparent; color: var(--muted); font-size: 12px; }
.topnav button[aria-pressed="true"] { background: var(--accent-soft); color: var(--accent); }
.app-shell[data-view="courses"] { display: block; }
.app-shell[data-view="courses"] main { max-width: 1280px; }
.course-context { display: flex; flex-wrap: wrap; gap: 12px; align-items: center; padding: 16px 20px; margin-bottom: 20px; background: var(--accent-soft); border: 1px solid var(--accent-border); border-radius: 9px; }
.course-context > div { margin-right: auto; }
.course-context .section-label { font-size: 9px; color: var(--accent-muted); }
.course-context p { font-size: 12px; color: var(--accent-text); margin: 4px 0 0; }
.course-context button { font-size: 11px; }
.course-access { padding: 24px; margin-bottom: 20px; }
.course-access h2 { font-size: 18px; margin-bottom: 8px; }
.course-access p { font-size: 13px; color: var(--muted); }
.course-access .signin-link { font-size: 12px; }
.course-intro { display: flex; align-items: center; gap: 40px; padding: 28px 32px; margin-bottom: 32px; background: linear-gradient(115deg, var(--accent-soft), var(--panel) 80%); border-color: var(--accent-border); }
.course-intro > div { flex: 1; }
.course-intro .section-label { font-size: 9px; color: var(--accent-muted); }
.course-intro h2 { font-size: 25px; font-weight: 650; letter-spacing: -.6px; margin: 10px 0; }
.course-intro p { font-size: 13px; color: var(--muted); max-width: 650px; margin-bottom: 0; }
.course-list-heading { display: flex; align-items: center; justify-content: space-between; gap: 12px; margin-bottom: 14px; }
.course-list-heading h2 { font-size: 15px; margin: 0; }
.course-list-heading button { font-size: 11px; }
.course-grid { display: grid; grid-template-columns: repeat(3, minmax(0, 1fr)); gap: 18px; }
.course-card { padding: 24px; text-align: left; display: flex; flex-direction: column; align-items: flex-start; white-space: normal; min-height: 220px; }
.course-card:hover { border-color: #a7a3f2; box-shadow: 0 4px 15px #443cb409; }
.course-card .section-label { font-size: 10px; color: var(--accent); }
.course-card h3 { font-size: 19px; line-height: 1.45; font-weight: 600; letter-spacing: -.4px; margin: 12px 0 8px; overflow-wrap: anywhere; }
.course-card p { font-size: 12px; color: var(--muted); font-weight: 400; flex: 1; }
.course-card .small { font-weight: 400; font-size: 11px; }
.course-card-link { color: var(--accent); font-size: 11px; margin-top: 18px; }
.course-detail-heading { display: flex; align-items: flex-start; gap: 20px; justify-content: space-between; margin: 20px 0 12px; }
.course-detail-heading h2 { font-size: 27px; letter-spacing: -.7px; font-weight: 650; margin: 8px 0; }
.course-detail-heading p, .course-goal { font-size: 13px; color: var(--muted); max-width: 750px; }
.course-heading-actions { display: flex; gap: 8px; margin-top: 12px; }
.course-heading-actions button { font-size: 11px; }
.course-progress-heading { display: flex; justify-content: space-between; gap: 20px; align-items: center; margin: 20px 0 24px; color: var(--muted); font-size: 12px; }
progress { width: min(250px, 40%); height: 7px; appearance: none; border: 0; border-radius: 10px; overflow: hidden; background: var(--accent-border); accent-color: var(--accent); }
progress::-webkit-progress-bar { background: var(--accent-border); border-radius: 10px; }
progress::-webkit-progress-value { background: var(--accent); border-radius: 10px; }
.learning-layout { display: grid; grid-template-columns: 280px minmax(0, 1fr); align-items: start; gap: 24px; }
.lesson-outline { padding: 18px 10px; }
.lesson-outline-heading { display: flex; align-items: center; justify-content: space-between; margin: 0 10px 10px; }
.lesson-outline-heading h3 { font-size: 13px; margin: 0; }
.lesson-outline-heading button { font-size: 10px; padding: 4px 6px; }
.lesson-item { display: flex; width: 100%; align-items: flex-start; gap: 10px; padding: 14px 10px; margin: 2px 0; background: transparent; text-align: left; white-space: normal; }
.lesson-item:hover { background: var(--hover); }
.lesson-item.active { background: var(--accent-soft); }
.lesson-item strong { display: block; font-size: 12px; line-height: 1.6; font-weight: 550; color: var(--strong); }
.lesson-item small { display: block; font-size: 10px; font-weight: 400; line-height: 1.6; color: var(--faint); margin-top: 4px; }
.lesson-step { display: grid; place-items: center; width: 23px; height: 23px; flex-shrink: 0; border-radius: 50%; background: var(--subtle); color: var(--faint); font-size: 10px; margin-top: 1px; }
.lesson-item.active .lesson-step { color: var(--accent); background: var(--accent-soft); }
.lesson-step.completed { color: var(--success); background: var(--success-soft); }
.lesson-panel { padding: 30px; }
.lesson-heading, .lesson-section-heading { display: flex; align-items: flex-start; justify-content: space-between; gap: 15px; }
.lesson-heading .section-label { font-size: 9px; color: var(--accent-muted); }
.lesson-heading h2 { font-size: 24px; line-height: 1.4; font-weight: 650; letter-spacing: -.5px; margin: 9px 0 10px; }
.lesson-heading p { font-size: 13px; color: var(--muted); }
.lesson-heading button { font-size: 10px; padding: 4px 7px; }
.lesson-order { display: flex; gap: 12px; margin: 4px 0 20px; }
.lesson-order button { font-size: 10px; padding: 4px 0; }
.lesson-panel h3 { font-size: 13px; margin: 24px 0 12px; }
#lesson-objectives { font-size: 13px; line-height: 1.85; color: var(--muted); padding-left: 20px; }
.lesson-content { white-space: pre-wrap; overflow-wrap: anywhere; font-size: 13px; line-height: 1.9; color: var(--muted); margin: 24px 0; }
.lesson-example pre { white-space: pre-wrap; overflow-wrap: anywhere; padding: 18px; background: var(--surface); border: 1px solid var(--border); border-radius: 7px; color: var(--strong); font: 11px/1.85 var(--mono); }
.lesson-example p { font-size: 12px; color: var(--muted); }
.lesson-section-heading { align-items: baseline; margin-top: 20px; }
.lesson-exercise { display: flex; align-items: center; justify-content: space-between; gap: 15px; padding: 16px; border: 1px solid var(--border); border-radius: 8px; margin-bottom: 10px; }
.lesson-exercise strong { font-size: 12px; font-weight: 550; }
.lesson-exercise p { font-size: 11px; margin: 5px 0 0; }
.lesson-exercise button { font-size: 11px; }
.exercise-feedback { white-space: pre-wrap; color: var(--accent-text); }
.attempt-reference { display: block; font: 9px/1.8 var(--mono); margin-top: 8px; overflow-wrap: anywhere; }
.lesson-notes { border-top: 1px solid var(--border); margin-top: 26px; padding-top: 24px; }
.lesson-notes label { font-size: 12px; }
.lesson-notes button { margin-top: 10px; font-size: 11px; }
.lesson-actions { display: flex; align-items: center; justify-content: space-between; gap: 10px; border-top: 1px solid var(--border); margin-top: 24px; padding-top: 20px; }
.lesson-actions button { font-size: 11px; }
#course-form > input, #course-form > select, #lesson-form > input { width: 100%; }
#course-form > label, #lesson-form > label { margin-top: 18px; }
.lesson-question-picker { display: grid; gap: 10px; max-height: 220px; overflow: auto; }
.question-choice { display: flex; gap: 10px; align-items: flex-start; margin: 0; padding: 10px; border: 1px solid var(--border); border-radius: 6px; font-size: 12px; line-height: 1.7; }
.question-choice input { width: auto; margin-top: 4px; }
@media (max-width: 1000px) {
  .course-grid { grid-template-columns: repeat(2, minmax(0, 1fr)); }
  .learning-layout { grid-template-columns: 240px minmax(0, 1fr); gap: 16px; }
  .lesson-panel { padding: 24px; }
  .course-detail-heading { flex-wrap: wrap; }
  .course-heading-actions { margin-top: 0; }
}
@media (max-width: 760px) {
  .topbar { gap: 12px; flex-wrap: wrap; height: auto; min-height: 64px; padding-top: 12px; padding-bottom: 12px; }
  .topnav { margin-left: auto; }
  .topnav button { font-size: 11px; min-height: 32px; padding: 4px 9px; }
  .status-pill { display: none; }
  .course-grid { grid-template-columns: 1fr; }
  .course-intro { display: block; padding: 24px; }
  .course-intro button { margin-top: 20px; }
  .learning-layout { display: block; }
  .lesson-outline { margin-bottom: 18px; }
  #lesson-list { display: flex; overflow-x: auto; gap: 6px; padding-bottom: 6px; }
  .lesson-item { min-width: 210px; flex: 0 0 210px; }
  .course-detail-heading h2 { font-size: 25px; }
  .course-progress-heading { align-items: flex-start; flex-direction: column; gap: 12px; }
  progress { width: 100%; }
  .lesson-panel { padding: 22px; }
  .lesson-exercise { flex-wrap: wrap; }
  .lesson-actions { flex-wrap: wrap; }
  .course-list-heading { flex-wrap: wrap; }
}

/* Shared editor geometry keeps the painted tokens aligned with editable text. */
.code-input { position: relative; flex: 1; min-width: 0; overflow: hidden; }
.code-highlight { position: absolute; inset: 0; overflow: hidden; padding-left: 12px; padding-right: 20px; color: var(--strong); pointer-events: none; white-space: pre; }
.code-highlight code { display: block; width: max-content; min-width: 100%; font: inherit; }
.code::selection { background: var(--selection); }
.library-item small > span:last-child { min-width: 0; overflow-wrap: anywhere; }
.library-item:focus-visible { outline-offset: -3px; }
.theme-toggle { font-size: 11px; min-height: 34px; padding: 5px 9px; }
.theme-toggle[aria-pressed="true"] { background: var(--accent-soft); border-color: var(--accent-border); color: var(--accent); }
:root[data-theme="dark"] .primary { color: #171426; }
.token.comment, .token.prolog, .token.doctype, .token.cdata { color: var(--syntax-comment); }
.token.keyword, .token.atrule, .token.boolean { color: var(--syntax-keyword); }
.token.string, .token.char, .token.attr-value, .token.regex { color: var(--syntax-string); }
.token.function, .token.class-name { color: var(--syntax-function); }
.token.number, .token.constant, .token.symbol { color: var(--syntax-number); }
.token.operator, .token.entity, .token.url { color: var(--syntax-operator); }
.token.punctuation { color: var(--muted); }
.token.property, .token.builtin, .token.tag, .token.attr-name { color: var(--syntax-function); }
@media (max-width: 760px) {
  .theme-toggle { margin-left: auto; }
  .theme-toggle span { display: none; }
}
@media (forced-colors: active) {
  .code-highlight { display: none; }
  .code { color: CanvasText; -webkit-text-fill-color: CanvasText; caret-color: CanvasText; }
}

.editor-scope { margin: 12px 20px; color: var(--muted); font-size: 11px; line-height: 1.65; }
.runner-code-details { margin: 0 20px 16px; color: var(--muted); font-size: 11px; }
.runner-code-details summary { cursor: pointer; padding: 5px 0; }
.runner-code-details summary .small { margin-left: 8px; font-size: 10px; }
.runner-code-details pre { margin: 10px 0 0; padding: 14px; max-height: 250px; overflow: auto; border: 1px solid var(--border); border-radius: 7px; background: var(--surface); color: var(--strong); font: 11px/1.7 var(--mono); }

/* Code identifiers are not prose; suppress native writing-error decorations. */
.code::spelling-error { text-decoration: none; }
.code::grammar-error { text-decoration: none; }