:root{--bg:#f7f7f5;--ink:#1a1a1a;--accent:#c8541a;--ok:#1a7a3c;--warn:#b3261e;--card:#fff;--line:#ddd8d0;font-family:system-ui,-apple-system,sans-serif}*{box-sizing:border-box}body{background:var(--bg);color:var(--ink);margin:0}main{max-width:640px;margin:0 auto;padding:16px}button{font:inherit;min-height:44px}.app-header{max-width:640px;margin:0 auto;padding:16px 16px 0}.app-header h1{margin:0;font-size:1.25rem}.update-toast{z-index:1000;background:var(--accent);color:#fff;min-height:44px;font:inherit;cursor:pointer;border:none;border-radius:999px;padding:0 20px;font-size:.9rem;font-weight:600;position:fixed;bottom:16px;left:50%;transform:translate(-50%);box-shadow:0 4px 16px #00000040}.course-map-header{justify-content:space-between;align-items:center;gap:12px;margin-bottom:16px;display:flex}.course-map-header h2{margin:0;font-size:1.1rem}.btn{cursor:pointer;white-space:nowrap;border:1px solid #0000;border-radius:8px;justify-content:center;align-items:center;min-height:44px;padding:0 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