:root{--primary:#0052cc;--accent:#28a745;--background:#f8f9fa;--surface:#f4f5f7;--text:#333;--text-light:#6b778c;--white:#fff;--border:#dfe1e6;--shadow:0 4px 12px #00000014;--font-family:"Inter", system-ui, -apple-system, sans-serif;font-family:var(--font-family);color:var(--text);background-color:var(--background);font-synthesis:none;text-rendering:optimizelegibility;-webkit-font-smoothing:antialiased;-moz-osx-font-smoothing:grayscale;font-weight:400;line-height:1.5}body{justify-content:center;min-width:320px;min-height:100vh;margin:0;display:flex}#app{box-sizing:border-box;width:100%;max-width:800px;margin:0 auto;padding:2rem}.header{justify-content:center;align-items:center;margin-bottom:4rem;padding-top:2rem;display:flex}.header-logo{width:auto;height:54px;display:block}.hero{text-align:center;margin-bottom:3rem}.hero h2{color:var(--primary);margin-bottom:1rem;font-size:2rem;font-weight:700}.hero p{color:var(--text-light);max-width:600px;margin-bottom:2rem;margin-left:auto;margin-right:auto;font-size:1.1rem}.download-button{background-color:var(--accent);color:var(--white);cursor:pointer;border:none;border-radius:8px;align-items:center;gap:.75rem;padding:1rem 2.5rem;font-size:1.25rem;font-weight:700;text-decoration:none;transition:background-color .2s,transform .1s;display:inline-flex;box-shadow:0 4px 6px #28a74533}.download-button:hover{background-color:#218838;transform:translateY(-1px)}.download-button:active{transform:translateY(0)}.manual-selector{color:var(--text-light);margin-top:1.5rem;font-size:.9rem}.manual-selector button{color:var(--primary);cursor:pointer;font-family:inherit;font-size:inherit;background:0 0;border:none;padding:0;text-decoration:underline}.walkthrough-container{margin-bottom:4rem}.walkthrough-grid{grid-template-columns:repeat(auto-fit,minmax(180px,1fr));gap:1rem;display:grid}.step-card{background:var(--white);box-shadow:var(--shadow);border:1px solid var(--border);text-align:left;border-radius:12px;padding:1.25rem;position:relative}.step-number{background:var(--primary);color:var(--white);border-radius:50%;justify-content:center;align-items:center;width:28px;height:28px;margin-bottom:1rem;font-size:.9rem;font-weight:700;display:flex}.step-card h3{color:var(--primary);margin:0 0 .5rem;font-size:1.1rem;font-weight:700}.step-card p{color:var(--text-light);margin:0;font-size:.95rem}.footer{border-top:1px solid var(--border);color:var(--text-light);text-align:left;padding-top:2rem}.policy-section h4{color:var(--primary);text-transform:uppercase;letter-spacing:.05em;margin-bottom:1.5rem;font-size:1.1rem}.policy-list{grid-template-columns:repeat(auto-fit,minmax(200px,1fr));gap:1rem;padding:0;list-style:none;display:grid}.policy-item{font-size:.9rem}.support-link{text-align:center;margin-top:3rem;padding-bottom:2rem;font-size:.9rem}.support-link a{color:var(--primary);font-weight:700;text-decoration:none}.os-choice-container{justify-content:center;gap:1rem;margin-top:2rem;display:flex}.os-choice-button{border:2px solid var(--primary);color:var(--primary);cursor:pointer;background:0 0;border-radius:6px;padding:.75rem 1.5rem;font-weight:700;transition:all .2s}.os-choice-button:hover{background-color:var(--primary);color:#fff}.hidden{display:none!important}@media (width<=600px){#app{padding:1rem}.hero h2{font-size:1.5rem}.walkthrough-grid{grid-template-columns:1fr}}.highlight-text{color:#d97706;margin-top:.5rem;font-weight:600;display:block}