:root{--bg: #f4f7fb;--surface: #ffffff;--ink: #1b2733;--ink-soft: #46586b;--brand: #1f6feb;--line: #cdd6e0;--surface-alt: #eef2f8;--emphasis: #d6263c;--touch: 64px}*{box-sizing:border-box}html,body,#root{margin:0;height:100%;color:var(--ink);font-family:Pretendard,Apple SD Gothic Neo,Malgun Gothic,system-ui,sans-serif;-webkit-tap-highlight-color:transparent}html{background:var(--bg)}body,#root{background:transparent}body{overscroll-behavior:none}button{font-family:inherit;cursor:pointer;border:none;background:none;color:inherit}.touch{min-height:var(--touch);min-width:var(--touch)}.app-shell{max-width:560px;margin:0 auto;min-height:100%;padding:16px;display:flex;flex-direction:column}.card{background:var(--surface);border-radius:20px;box-shadow:0 4px 14px #1b273314}.btn-primary{min-height:var(--touch);border-radius:16px;background:var(--brand);color:#fff;font-size:20px;font-weight:700;padding:0 24px;display:inline-flex;align-items:center;justify-content:center;gap:8px;transition:transform .1s ease,filter .1s ease}.btn-primary:active{transform:scale(.97);filter:brightness(.95)}.btn-primary:disabled{opacity:.5}.btn-ghost{min-height:56px;border-radius:14px;border:2px solid var(--line);background:var(--surface);font-size:18px;font-weight:600;padding:0 18px;display:inline-flex;align-items:center;justify-content:center;gap:8px}.choice-grid{display:grid;grid-template-columns:repeat(2,1fr);gap:12px}.choice-btn{min-height:72px;border-radius:18px;border:3px solid var(--line);background:var(--surface);font-size:23px;font-weight:800;display:flex;align-items:center;justify-content:center;position:relative;transition:transform .1s ease,border-color .15s ease,background .15s ease}.choice-btn:active{transform:scale(.97)}.choice-btn.correct{border-color:#0b8a6b;background:#e6f7f0}.choice-btn.wrong{border-color:#d2691e;background:#fdf0e4;animation:shake .22s ease}.choice-btn .mark{position:absolute;top:6px;right:6px}@keyframes shake{0%,to{transform:translate(0)}25%{transform:translate(-6px)}75%{transform:translate(6px)}}@keyframes pop{0%{transform:scale(.8);opacity:0}to{transform:scale(1);opacity:1}}.pop{animation:pop .3s ease}@media (prefers-reduced-motion: reduce){*,*:before,*:after{animation-duration:.001ms!important;transition-duration:.001ms!important}}.prompt{font-size:clamp(20px,5.6vw,26px);font-weight:800;line-height:1.34;margin:0}.prompt--long{font-size:clamp(18px,4.8vw,23px);line-height:1.32}.prompt--xlong{font-size:clamp(16px,4.2vw,20px);line-height:1.3}.prompt-em{color:var(--emphasis);font-weight:900}.reading-passage{background:var(--surface-alt, #eef2f8);border:2px solid var(--line);border-radius:16px;padding:14px 16px;margin-bottom:14px}.passage-text{font-size:clamp(17px,4.6vw,21px);font-weight:600;line-height:1.5;margin:0;color:var(--ink);overflow-wrap:anywhere}.passage-text--long{font-size:clamp(16px,4.2vw,19px);line-height:1.45}.passage-text--xlong{font-size:clamp(16px,3.8vw,18px);line-height:1.4}.feedback{font-size:19px;font-weight:700;display:flex;align-items:center;gap:8px}.subject-card{border-radius:22px;padding:22px;display:flex;align-items:center;gap:16px;border:3px solid var(--line);background:var(--surface);width:100%;text-align:left}.subject-card:active{transform:scale(.98)}.problem-asset{width:100%;display:flex;justify-content:center;align-items:center;overflow:hidden}.problem-asset svg{width:100%;height:auto;max-width:100%;display:block}.asset-clock{width:min(70vw,320px);max-width:100%}.asset-clock svg{width:100%;height:auto}.card{max-width:100%}.prompt{overflow-wrap:anywhere}