.card{width:100%;max-width:420px;min-height:100vh;min-height:100dvh;display:flex;flex-direction:column;padding:var(--padding)}.card-front{flex:1;display:flex;flex-direction:column;justify-content:center;align-items:center;text-align:center;gap:16px;cursor:pointer}.card-category{font-size:var(--font-size-small);text-transform:uppercase;letter-spacing:2px;border:var(--border);padding:4px 12px}.card-title{font-size:var(--font-size-title);font-weight:700;line-height:1.2}.card-hook{font-size:var(--font-size-hook);font-style:italic;line-height:1.4}.card-hint{font-size:var(--font-size-small);opacity:.4;margin-top:24px}.card-back{flex:1;display:flex;flex-direction:column;justify-content:center;gap:16px}.card-definition{font-size:var(--font-size-body);line-height:1.6;border-bottom:var(--border);padding-bottom:16px}.card-challenge{display:flex;flex-direction:column;gap:8px}.card-question{font-size:var(--font-size-body);font-weight:700;margin-bottom:4px}.answer-btn{font-size:var(--font-size-body)}.answer-btn:disabled{cursor:default}.answer-correct{background:var(--color-correct);color:var(--color-correct-text);border-color:var(--color-correct)}.answer-incorrect{background:var(--color-incorrect);color:var(--color-incorrect-text);border-color:var(--color-incorrect)}.card-explanation{font-size:var(--font-size-small);line-height:1.5;border:var(--border);padding:12px;margin-top:4px}.intro{flex:1;display:flex;flex-direction:column;justify-content:center;align-items:center;text-align:center;gap:16px;cursor:pointer}.intro-title{font-size:var(--font-size-title);font-weight:700;line-height:1.2}.intro-tagline{font-size:var(--font-size-hook);font-style:italic;line-height:1.4}.intro-steps{margin-top:24px;display:flex;flex-direction:column;gap:4px;font-size:var(--font-size-body);font-weight:700}.progress-screen{flex:1;display:flex;flex-direction:column;justify-content:center;align-items:center;text-align:center;gap:24px}.progress-title{font-size:var(--font-size-title);font-weight:700}.progress-mastery{display:flex;align-items:baseline;gap:4px}.progress-count{font-size:3rem;font-weight:700}.progress-separator{font-size:2rem;opacity:.4}.progress-total{font-size:2rem;opacity:.6}.progress-label{font-size:var(--font-size-body);margin-left:8px;opacity:.6}.progress-details{font-size:var(--font-size-small);opacity:.5}.settings-screen{flex:1;display:flex;flex-direction:column;justify-content:center;align-items:center;text-align:center;gap:24px}.settings-title{font-size:var(--font-size-title);font-weight:700}.settings-actions{display:flex;flex-direction:column;gap:8px;width:100%}.settings-reset{text-align:center}.settings-reset-confirm{background:var(--color-incorrect);color:var(--color-incorrect-text);border-color:var(--color-incorrect)}.settings-cancel{text-align:center;opacity:.6}*,*:before,*:after{margin:0;padding:0;box-sizing:border-box}:root{--color-primary: #000000;--color-bg: #ffffff;--color-correct: #2d6a4f;--color-incorrect: #a4161a;--color-correct-text: #ffffff;--color-incorrect-text: #ffffff;--font-mono: "Roboto Mono", "Courier New", monospace;--border: 2px solid #000000;--padding: 20px;--font-size-title: 1.5rem;--font-size-hook: 1.1rem;--font-size-body: .85rem;--font-size-button: .9rem;--font-size-small: .75rem}html,body,#app{height:100%;width:100%}body{font-family:var(--font-mono);background-color:var(--color-bg);color:var(--color-primary);-webkit-font-smoothing:antialiased;line-height:1.5}#app{display:flex;flex-direction:column;align-items:center;justify-content:center}button{font-family:var(--font-mono);font-size:var(--font-size-button);background:var(--color-bg);color:var(--color-primary);border:var(--border);border-radius:0;padding:14px var(--padding);cursor:pointer;width:100%;text-align:left;line-height:1.4;transition:none}button:active{background:var(--color-primary);color:var(--color-bg)}.next-btn{position:fixed;bottom:0;width:100%;max-width:420px;left:50%;transform:translate(-50%);text-align:center;font-weight:700;border-top:var(--border);border-left:none;border-right:none;border-bottom:none;background:var(--color-primary);color:var(--color-bg);padding:16px}.next-btn:active{background:var(--color-bg);color:var(--color-primary)}.nav-bar{position:fixed;top:0;left:50%;transform:translate(-50%);width:100%;max-width:420px;display:flex;justify-content:flex-end;gap:16px;padding:12px var(--padding);z-index:10}.nav-link{font-family:var(--font-mono);font-size:var(--font-size-small);background:none;border:none;padding:4px 0;width:auto;cursor:pointer;opacity:.5;text-decoration:none;color:var(--color-primary)}.nav-link:active{opacity:1;background:none;color:var(--color-primary)}.nav-back{font-size:var(--font-size-small);background:none;border:none;padding:4px 0;width:auto;cursor:pointer;opacity:.5}.nav-back:active{opacity:1;background:none;color:var(--color-primary)}.error-screen{display:flex;align-items:center;justify-content:center;height:100vh;padding:var(--padding);text-align:center;font-size:var(--font-size-body)}.sr-only{position:absolute;width:1px;height:1px;padding:0;margin:-1px;overflow:hidden;clip:rect(0,0,0,0);border:0}