/* components.css — buttons, sidebar, callouts, code, exercises, quiz, flashcards, cards */
.btn { background: var(--panel2); color: var(--text); border: 1px solid var(--border); border-radius: 8px; padding: 7px 14px; font: inherit; font-size: 14px; cursor: pointer; text-decoration: none; display: inline-block; }
.btn:hover { border-color: var(--accent); }
.btn:disabled { opacity: .5; cursor: not-allowed; }
.btn.primary { background: var(--accent); color: #0b0e1c; border-color: var(--accent); font-weight: 600; }
.btn.small { padding: 3px 10px; font-size: 13px; }
.btn.ghost { background: transparent; }

/* sidebar */
.sidebar .progress, .card .bar { height: 6px; background: var(--panel2); border-radius: 4px; overflow: hidden; margin: 6px 0 4px; }
.sidebar .progress i, .card .bar i { display: block; height: 100%; background: linear-gradient(90deg, var(--accent), var(--accent2)); }
.sidebar small { color: var(--muted); }
.sidebar input[type=search] { width: 100%; margin: 10px 0 4px; padding: 7px 10px; border-radius: 8px; border: 1px solid var(--border); background: var(--panel2); color: var(--text); font: inherit; font-size: 14px; }
.sidebar h4 { margin: 18px 0 4px; font-size: 12px; text-transform: uppercase; letter-spacing: .08em; color: var(--muted); }
.sidebar ol { list-style: none; margin: 0; padding: 0; }
.sidebar li a { display: flex; gap: 10px; align-items: center; padding: 7px 10px; border-radius: 8px; text-decoration: none; color: var(--text); font-size: 15px; }
.sidebar li a:hover { background: var(--panel2); }
.sidebar li a.active { background: var(--panel2); box-shadow: inset 3px 0 0 var(--accent); }
.sidebar li a .n { width: 24px; height: 24px; border-radius: 50%; border: 1px solid var(--border); display: grid; place-items: center; font-size: 12px; color: var(--muted); flex: none; }
.sidebar li a.done .n { background: var(--good); border-color: var(--good); color: #06240f; }
.sidebar li a .t { flex: 1; }
.sidebar li a .tag { font-size: 11px; color: var(--accent2); border: 1px solid var(--border); border-radius: 6px; padding: 0 5px; }
.sidebar .extras { margin-top: 18px; border-top: 1px solid var(--border); padding-top: 8px; }
.sidebar .foot { margin-top: 20px; font-size: 13px; }

/* callouts + lesson sections */
.callout { border-left: 4px solid var(--accent); background: var(--panel); padding: 12px 16px; border-radius: 0 var(--radius) var(--radius) 0; margin: 18px 0; }
.callout.tip { border-color: var(--accent2); } .callout.warn { border-color: var(--warn); } .callout.bad { border-color: var(--bad); }
.callout b.t { display: block; margin-bottom: 2px; }
.objectives, .takeaways, .realworld { border: 1px solid var(--border); border-radius: var(--radius); padding: 4px 20px 10px; margin: 20px 0; background: var(--panel); }
.objectives h3, .takeaways h3, .realworld h3 { margin: 12px 0 4px; color: var(--accent); font-size: .95rem; text-transform: uppercase; letter-spacing: .06em; }
.objectives ul, .takeaways ul { margin: 4px 0 6px; padding-left: 22px; }
.realworld { border-color: var(--accent2); }
.realworld h3 { color: var(--accent2); }
details { background: var(--panel); border: 1px solid var(--border); border-radius: 10px; padding: 8px 14px; margin: 12px 0; }
details > summary { cursor: pointer; font-weight: 600; }
.notes textarea { width: 100%; min-height: 90px; background: var(--panel); color: var(--text); border: 1px solid var(--border); border-radius: 10px; padding: 10px; font: inherit; resize: vertical; }

/* code blocks */
.codebox { position: relative; margin: 14px 0; }
.codebox pre { margin: 0; background: var(--code); border: 1px solid var(--border); border-radius: var(--radius); padding: 14px 16px; overflow: auto; line-height: 1.5; }
.codebox pre code { background: none; padding: 0; font-size: 14px; }
.codebox .bar { display: flex; gap: 6px; align-items: center; justify-content: flex-end; padding: 4px 0; font-size: 12px; color: var(--muted); }
.codebox .bar .lang { margin-right: auto; text-transform: uppercase; letter-spacing: .06em; }
.tk-kw { color: var(--tok-kw); } .tk-str { color: var(--tok-str); } .tk-num { color: var(--tok-num); } .tk-com { color: var(--tok-com); font-style: italic; } .tk-fn { color: var(--tok-fn); }
.editor { width: 100%; min-height: 120px; background: var(--code); color: var(--text); border: 1px solid var(--border); border-radius: var(--radius); padding: 12px 14px; font: 14px/1.5 ui-monospace, Consolas, "Cascadia Mono", monospace; resize: vertical; tab-size: 4; white-space: pre; overflow: auto; }
.editor:focus { border-color: var(--accent); outline: none; }
.output { background: var(--code); border: 1px solid var(--border); border-radius: var(--radius); padding: 10px 14px; margin-top: 8px; font: 13.5px/1.5 ui-monospace, Consolas, monospace; white-space: pre-wrap; max-height: 360px; overflow: auto; }
.output:empty { display: none; }
.output .err { color: var(--bad); } .output .dim { color: var(--muted); } .output img { background: #fff; border-radius: 8px; margin: 6px 0; display: block; }
.checks { list-style: none; padding: 0; margin: 8px 0; }
.checks li { padding: 3px 0; font-size: 14px; }
.checks li.pass::before { content: "✅ "; } .checks li.fail::before { content: "❌ "; }

/* demos */
.demo { background: var(--panel); border: 1px solid var(--border); border-radius: var(--radius); padding: 16px; margin: 22px 0; }
.demo > h4 { margin: 0 0 10px; font-size: 14px; text-transform: uppercase; letter-spacing: .06em; color: var(--accent2); }
.demo canvas { max-width: 100%; background: var(--code); border-radius: 8px; display: block; }
.controls { display: flex; flex-wrap: wrap; gap: 12px; align-items: center; margin: 10px 0; }
.controls label { font-size: 14px; color: var(--muted); display: flex; gap: 8px; align-items: center; }
.controls input[type=range] { accent-color: var(--accent); }
.controls select, .controls input[type=number], .controls input[type=text] { background: var(--panel2); color: var(--text); border: 1px solid var(--border); border-radius: 6px; padding: 5px 8px; font: inherit; }
.readout { font: 14px ui-monospace, Consolas, monospace; color: var(--muted); margin-top: 6px; min-height: 1.4em; white-space: pre-wrap; }

/* exercises */
.exercise { border: 1px solid var(--border); border-left: 4px solid var(--warn); border-radius: var(--radius); background: var(--panel); padding: 4px 18px 16px; margin: 26px 0; }
.exercise.solved { border-left-color: var(--good); }
.exercise > h3 { margin: 12px 0 6px; color: var(--text); font-size: 1.05rem; }
.exercise .badge { font-size: 12px; background: var(--warn); color: #1a1405; border-radius: 6px; padding: 1px 8px; margin-right: 8px; font-weight: 700; }
.exercise.solved .badge { background: var(--good); color: #06240f; }
.exercise .actions { display: flex; flex-wrap: wrap; gap: 8px; margin: 8px 0; }
.hint { background: var(--panel2); border-radius: 8px; padding: 8px 12px; margin: 6px 0; font-size: 14.5px; }

/* quiz */
.quiz { margin-top: 36px; border: 1px solid var(--border); border-radius: var(--radius); padding: 6px 18px 18px; background: var(--panel); }
.quiz .q { margin-top: 18px; }
.quiz .opt { display: block; width: 100%; text-align: left; margin: 6px 0; padding: 9px 12px; border-radius: 8px; border: 1px solid var(--border); background: var(--panel2); color: var(--text); font: inherit; cursor: pointer; }
.quiz .opt:hover:not(:disabled) { border-color: var(--accent); }
.quiz .opt.right { border-color: var(--good); background: rgba(74,222,128,.15); }
.quiz .opt.wrong { border-color: var(--bad); background: rgba(248,113,113,.15); }
.quiz .why { font-size: 14px; color: var(--muted); margin-top: 4px; }
.quiz .score { margin-top: 16px; font-weight: 600; }

/* checklist (project milestones) */
ul.checklist { list-style: none; padding-left: 4px; }
ul.checklist li { margin: 6px 0; display: flex; gap: 10px; align-items: flex-start; }
ul.checklist input { margin-top: 6px; accent-color: var(--good); }
ul.checklist li.on span { color: var(--muted); text-decoration: line-through; }

/* flashcards */
.flash { max-width: 560px; margin: 24px 0; }
.flash .card-face { min-height: 180px; display: grid; place-items: center; text-align: center; padding: 28px; font-size: 1.2rem; background: var(--panel); border: 1px solid var(--border); border-radius: 16px; cursor: pointer; }
.flash .card-face.back { border-color: var(--accent2); font-size: 1.05rem; }
.flash .row { display: flex; gap: 10px; margin-top: 12px; flex-wrap: wrap; }

.pager { display: flex; justify-content: space-between; gap: 10px; margin-top: 36px; flex-wrap: wrap; }

/* home cards */
.cards { display: grid; grid-template-columns: repeat(auto-fit, minmax(260px, 1fr)); gap: 20px; margin-top: 28px; }
.card { display: block; text-decoration: none; color: var(--text); background: var(--panel); border: 1px solid var(--border); border-radius: 16px; padding: 24px; transition: .15s; }
.card:hover { transform: translateY(-4px); border-color: var(--accent); }
.card .ico { font-size: 34px; }
.card h3 { margin: 10px 0 4px; font-size: 1.3rem; color: var(--text); }
.card p { color: var(--muted); margin: 0 0 14px; font-size: 15px; }
.card small { color: var(--muted); }

.toast { position: fixed; bottom: 20px; right: 20px; background: var(--panel2); border: 1px solid var(--accent); border-radius: 10px; padding: 10px 16px; z-index: 99; box-shadow: 0 6px 24px #0007; }

/* "coming soon" course cards */
.card.soon { opacity: .55; cursor: not-allowed; }
.card.soon:hover { transform: none; border-color: var(--border); }
.badge-soon { display: inline-block; white-space: nowrap; margin-top: 4px; font-size: 11px; vertical-align: middle; background: var(--panel2); border: 1px solid var(--border); border-radius: 6px; padding: 1px 8px; color: var(--warn); font-weight: 600; }