:root{font-family:system-ui,sans-serif;color:#111827;background:radial-gradient(circle at top,#ecfeff,#f8fafc 40%,#f1f5f9 100%)}*{box-sizing:border-box}body{margin:0}main{max-width:720px;margin:0 auto;padding:24px 16px 64px}.card{background:hsla(0,0%,100%,.85);border:1px solid #e5e7eb;border-radius:12px;padding:16px;margin-bottom:12px}button,input{font:inherit}button{cursor:pointer}