:root{--bg: #fdfaf3;--surface: #ffffff;--surface-2: #f6f2ea;--ink: #16202c;--ink-2: #44525f;--muted: #6b7684;--line: #ddd6c9;--line-strong: #b9b0a0;--tone-a: #0f6f8c;--tone-a-soft: #d9eef4;--tone-b: #bf6b12;--tone-b-soft: #fbebd3;--tone-c: #7340b0;--tone-c-soft: #ece2fa;--tone-student: #2f4fd0;--tone-student-soft: #e1e7fd;--tone-reference: #8b95a3;--good: #17704a;--good-soft: #dcf2e7;--attention: #9e3f1f;--attention-soft: #fbe6dd;--focus: #1b46d6;--radius: 14px;--radius-sm: 9px;--shadow: 0 1px 2px rgba(20, 30, 40, .06), 0 8px 24px rgba(20, 30, 40, .06);--pad: clamp(14px, 2vw, 24px)}*{box-sizing:border-box}html{-webkit-text-size-adjust:100%}body{margin:0;background:var(--bg);color:var(--ink);font-family:Segoe UI,system-ui,-apple-system,Helvetica Neue,Arial,sans-serif;font-size:16px;line-height:1.55}h1,h2,h3,h4{line-height:1.22;margin:0 0 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