:root{--primary: #87CEEB;--success: #90EE90;--warning: #f59e0b;--error: #ef4444;--bg-primary: #F0F8FF;--bg-secondary: #ffffff;--bg-tertiary: #f0f0f0;--text-primary: #333333;--text-secondary: #555555;--border: #dddddd}*{box-sizing:border-box;-webkit-tap-highlight-color:transparent}body{margin:0;padding:0;font-family:PT Sans,-apple-system,BlinkMacSystemFont,Segoe UI,Roboto,Oxygen,Ubuntu,Cantarell,Fira Sans,Droid Sans,Helvetica Neue,sans-serif;-webkit-font-smoothing:antialiased;-moz-osx-font-smoothing:grayscale;background:var(--bg-primary);color:var(--text-primary);overflow-x:hidden}.app{min-height:100vh;display:flex;flex-direction:column;padding:1rem;max-width:600px;margin:0 auto}.app-header{display:flex;justify-content:space-between;align-items:center;padding:.5rem 0 1rem}.app-header h1{margin:0;font-size:1.5rem}.icon-btn{background:var(--bg-tertiary);border:none;color:var(--text-primary);padding:.5rem 1rem;border-radius:.5rem;font-size:1rem;cursor:pointer;transition:all 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.75rem;border-radius:999px;font-size:.75rem;font-weight:600;margin:0 auto}.word-translation{font-size:1.75rem;font-weight:600;color:var(--success);margin-bottom:1rem}.word-detail{font-size:.9rem;line-height:1.6;color:var(--text-secondary);text-align:left}.word-detail strong{color:var(--text-primary)}.tap-hint{text-align:center;font-size:.875rem;color:var(--text-secondary);opacity:.6;margin-top:.5rem}.swipe-hint{position:absolute;bottom:-2.5rem;left:50%;transform:translate(-50%);font-size:.875rem;color:var(--text-secondary);opacity:.7;white-space:nowrap;pointer-events:none}.swipe-indicator{position:absolute;top:50%;font-size:1.5rem;font-weight:700;padding:1rem 1.5rem;border-radius:1rem;color:#fff;pointer-events:none;z-index:5;box-shadow:0 4px 12px #00000026}.swipe-indicator.review{left:-.5rem;background-color:var(--warning);transform:translateY(-50%) rotate(-10deg)}.swipe-indicator.know{right:-.5rem;background-color:var(--success);transform:translateY(-50%) 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.5rem;text-align:center}.vocab-count{text-align:center;color:var(--text-secondary);margin-bottom:2rem}.setup-options{display:flex;flex-direction:column;gap:1rem;margin-bottom:1.5rem}.option-group{display:flex;flex-direction:column;gap:.5rem}.option-group label{font-size:.875rem;font-weight:600;color:var(--text-secondary);text-transform:uppercase}.option-group select{padding:.75rem;background:var(--bg-tertiary);border:1px solid var(--border);border-radius:.5rem;color:var(--text-primary);font-size:1rem;cursor:pointer}.filtered-count{text-align:center;font-size:.875rem;color:var(--text-secondary);margin-bottom:1rem}.start-btn{width:100%;padding:1rem;font-size:1rem;font-weight:600;background:var(--primary);color:#fff;border:none;border-radius:.5rem;cursor:pointer;transition:all .2s}.start-btn:hover:not(:disabled){transform:scale(1.02);box-shadow:0 10px 30px #87ceeb66}.start-btn:disabled{opacity:.5;cursor:not-allowed}.session-complete h2{font-size:2rem;margin:0 0 2rem}.summary{display:grid;grid-template-columns:repeat(3,1fr);gap:1rem;margin-bottom:2rem;width:100%;max-width:500px}.summary-stat{background:var(--bg-secondary);padding:1.5rem 1rem;border-radius:.75rem;display:flex;flex-direction:column;gap:.5rem;border:1px solid var(--border)}.summary-stat.known{border-color:var(--success)}.summary-stat.review{border-color:var(--warning)}.summary-label{font-size:.75rem;color:var(--text-secondary);text-transform:uppercase}.summary-value{font-size:2rem;font-weight:700}@media(max-width:480px){.word-main{font-size:2rem}.word-translation{font-size:1.5rem}.flashcard-container{height:400px}.flashcard-face,.setup-card{padding:1.5rem}}@media(min-width:768px){.app{padding:2rem}}