:root{--purple: #673AB7;--purple-light: #7C4DFF;--purple-dark: #512DA8;--card-bg: #fff;--bg: #F0EBF8;--text: #202124;--text-secondary: #5f6368;--error: #d93025;--border: #dadce0;--radius: 8px;--gold: #F9A825}[data-astro-cid-f4dgfqqy]{margin:0;padding:0;box-sizing:border-box}body{font-family:Google Sans,Roboto,-apple-system,sans-serif;background:var(--bg);color:var(--text);line-height:1.6;padding:0 16px 40px}.container[data-astro-cid-f4dgfqqy]{max-width:640px;margin:0 auto;padding-top:12px}.course-content[data-astro-cid-f4dgfqqy]{display:none}.course-content[data-astro-cid-f4dgfqqy].show{display:block}.header-card[data-astro-cid-f4dgfqqy]{background:var(--card-bg);border-radius:var(--radius);border-top:10px solid var(--purple);padding:24px;margin-bottom:12px}.header-top[data-astro-cid-f4dgfqqy]{display:flex;justify-content:space-between;align-items:center;margin-bottom:8px}.header-id[data-astro-cid-f4dgfqqy]{font-size:13px;font-weight:600;color:var(--purple)}.lang-switch[data-astro-cid-f4dgfqqy]{font-size:13px;color:var(--purple);text-decoration:none;padding:4px 10px;border:1px solid var(--purple);border-radius:4px}.lang-switch[data-astro-cid-f4dgfqqy]:hover{background:#673ab714}.header-card[data-astro-cid-f4dgfqqy] h1[data-astro-cid-f4dgfqqy]{font-size:22px;font-weight:400;margin-bottom:4px}.header-card[data-astro-cid-f4dgfqqy] .ball[data-astro-cid-f4dgfqqy]{font-size:14px;color:var(--gold)}.card[data-astro-cid-f4dgfqqy]{background:var(--card-bg);border-radius:var(--radius);border:1px solid var(--border);padding:20px 24px;margin-bottom:12px}.card[data-astro-cid-f4dgfqqy] h2[data-astro-cid-f4dgfqqy]{font-size:16px;font-weight:500;margin-bottom:10px;display:flex;align-items:center;gap:8px}.card[data-astro-cid-f4dgfqqy] ul[data-astro-cid-f4dgfqqy]{padding-left:20px}.card[data-astro-cid-f4dgfqqy] li[data-astro-cid-f4dgfqqy]{font-size:14px;margin-bottom:4px}.card[data-astro-cid-f4dgfqqy] p[data-astro-cid-f4dgfqqy]{font-size:14px;color:var(--text-secondary)}.video-row[data-astro-cid-f4dgfqqy]{display:flex;align-items:center;gap:8px;margin-top:10px;font-size:13px}.video-row[data-astro-cid-f4dgfqqy]+.video-row[data-astro-cid-f4dgfqqy]{margin-top:8px}.video-label[data-astro-cid-f4dgfqqy]{font-weight:500;color:var(--text);white-space:nowrap}.video-url[data-astro-cid-f4dgfqqy]{color:var(--purple);word-break:break-all;text-decoration:none}.video-url[data-astro-cid-f4dgfqqy]:hover{text-decoration:underline}.copy-btn[data-astro-cid-f4dgfqqy]{background:none;border:1px solid var(--border);border-radius:4px;padding:3px 8px;font-size:12px;color:var(--text-secondary);cursor:pointer;white-space:nowrap;flex-shrink:0}.copy-btn[data-astro-cid-f4dgfqqy]:hover{border-color:var(--purple);color:var(--purple)}details[data-astro-cid-f4dgfqqy]{margin-top:8px}details[data-astro-cid-f4dgfqqy] summary[data-astro-cid-f4dgfqqy]{cursor:pointer;font-size:14px;font-weight:500;color:var(--purple);padding:6px 0}details[data-astro-cid-f4dgfqqy] summary[data-astro-cid-f4dgfqqy]:hover{text-decoration:underline}.material-list[data-astro-cid-f4dgfqqy]{list-style:none;margin:8px 0 0;padding:0}.material-list[data-astro-cid-f4dgfqqy] li[data-astro-cid-f4dgfqqy]{border-bottom:1px solid var(--border)}.material-list[data-astro-cid-f4dgfqqy] li[data-astro-cid-f4dgfqqy]:last-child{border-bottom:0}.material-list[data-astro-cid-f4dgfqqy] a[data-astro-cid-f4dgfqqy]{display:flex;justify-content:space-between;align-items:center;padding:12px 4px;color:var(--purple);text-decoration:none;font-size:14px}.material-list[data-astro-cid-f4dgfqqy] a[data-astro-cid-f4dgfqqy]:hover{color:var(--purple-dark);background:#faf6ff;padding-left:8px}.material-list[data-astro-cid-f4dgfqqy] .ext[data-astro-cid-f4dgfqqy]{color:var(--text-secondary);font-size:12px;margin-left:12px}.hw-link[data-astro-cid-f4dgfqqy]{display:inline-block;margin-top:10px;font-size:14px;color:var(--purple);text-decoration:none;font-weight:500}.hw-link[data-astro-cid-f4dgfqqy]:hover{text-decoration:underline}.back-link[data-astro-cid-f4dgfqqy]{display:inline-block;font-size:13px;color:var(--text-secondary);text-decoration:none;margin-bottom:12px}.back-link[data-astro-cid-f4dgfqqy]:hover{color:var(--purple)}