:root{--bg: #ffffff;--surface-1: #ffffff;--surface-2: #f5f5f5;--surface-3: #e5e5e5;--text-1: #1a1a1a;--text-2: #4a4a4a;--text-3: #7a7a7a;--border: #e0e0e0;--accent: #3b82f6;--accent-light: #93c5fd}[data-theme=dark]{--bg: #1a1a1a;--surface-1: #262626;--surface-2: #333333;--surface-3: #404040;--text-1: #ffffff;--text-2: #d4d4d4;--text-3: #a3a3a3;--border: #404040;--accent: #60a5fa;--accent-light: #1d4ed8}body{margin:0;font-family:system-ui,-apple-system,sans-serif;background:var(--bg);color:var(--text-1)}button{font-family:inherit}.modal-backdrop{position:fixed;top:0;left:0;width:100%;height:100%;background:#00000080;display:flex;justify-content:center;align-items:center;z-index:1000}.modal-content{background:#fff;padding:2rem;border-radius:8px;box-shadow:var(--shadow)}@keyframes fadeIn{0%{opacity:0}to{opacity:1}}@keyframes slideIn{0%{transform:translateY(20px);opacity:0}to{transform:translateY(0);opacity:1}}.fade-in{animation:fadeIn .3s ease-out}.slide-in{animation:slideIn .3s ease-out}@media (max-width: 768px){.container,.input-section,.result-section{padding:1rem}.numbers-input{flex-direction:column}.line-item{grid-template-columns:30px 1fr 40px}.result-grid{grid-template-columns:1fr}.buttons{flex-direction:column}button{width:100%}}button,input,textarea{transition:all .2s ease}button:hover{transform:translateY(-1px);box-shadow:0 2px 8px #0000001a}button:active{transform:translateY(0)}input:focus,textarea:focus{border-color:var(--primary-color);box-shadow:0 0 0 2px #4caf501a}.modal{animation:fadeIn .3s ease-out}.modal-content{animation:slideIn .3s ease-out}