*,*:before,*:after{box-sizing:border-box;margin:0;padding:0}:root{--color-bg: #ffffff;--color-surface: #f8f8f8;--color-border: #e8e8e8;--color-text: #1a1a1a;--color-text-secondary: #888;--color-accent: #1a1a1a;--radius-card: 8px;--radius-sm: 4px;--shadow-card: 0 2px 8px rgba(0, 0, 0, .06);--safe-bottom: env(safe-area-inset-bottom, 0px)}html,body{height:100%;background:var(--color-bg);color:var(--color-text);font-family:-apple-system,BlinkMacSystemFont,PingFang SC,Helvetica Neue,sans-serif;font-size:15px;line-height:1.5;-webkit-font-smoothing:antialiased;overscroll-behavior:none}#app{height:100%;display:flex;flex-direction:column}button{cursor:pointer;border:none;background:none;font:inherit;color:inherit}input,textarea{font:inherit;color:inherit;border:none;outline:none;background:none}a{color:inherit;text-decoration:none}.btn-primary{display:block;width:100%;padding:14px;background:var(--color-accent);color:#fff;border-radius:var(--radius-sm);font-size:16px;font-weight:500;text-align:center;transition:opacity .15s}.btn-primary:active{opacity:.75}.btn-primary:disabled{opacity:.35;cursor:not-allowed}.btn-ghost{padding:10px 16px;border-radius:var(--radius-sm);font-size:14px;color:var(--color-text-secondary);transition:background .15s}.btn-ghost:active{background:var(--color-surface)}.checkerboard{background-image:linear-gradient(45deg,#e0e0e0 25%,transparent 25%),linear-gradient(-45deg,#e0e0e0 25%,transparent 25%),linear-gradient(45deg,transparent 75%,#e0e0e0 75%),linear-gradient(-45deg,transparent 75%,#e0e0e0 75%);background-size:16px 16px;background-position:0 0,0 8px,8px -8px,-8px 0px}