*{margin:0;padding:0;box-sizing:border-box}:root{--bg: #000000;--surface: #0a0f0d;--surface-hover: #111a16;--border: #1e2a24;--border-hover: #4a6356;--text-primary: #f0fdf4;--text-secondary: #6b7f75;--text-tertiary: #4a6356;--accent: #10b981;--accent-hover: #059669;--accent-dim: rgba(16, 185, 129, .14);--success: #10b981;--error: #ef4444;--warning: #f59e0b}body{font-family:-apple-system,BlinkMacSystemFont,Segoe UI,Roboto,sans-serif;background:var(--bg);color:var(--text-primary);min-height:100vh;display:flex;align-items:center;justify-content:center;padding:16px}#checkout-app{width:100%;max-width:420px}.checkout-card{background:var(--surface);border:1px solid var(--border);border-radius:16px;overflow:hidden}.checkout-header{padding:20px 24px;border-bottom:1px solid var(--border)}.logo{display:flex;align-items:center;gap:10px;font-size:18px;font-weight:700;color:var(--text-primary)}.state{padding:32px 24px;text-align:center}.spinner{width:40px;height:40px;border:3px solid var(--border);border-top-color:var(--accent);border-radius:50%;animation:spin .8s linear infinite;margin:0 auto 16px}@keyframes spin{to{transform:rotate(360deg)}}.invoice-name{font-size:20px;font-weight:700;margin-bottom:4px}.invoice-description{font-size:14px;color:var(--text-secondary);margin-bottom:24px}.qr-container{display:flex;justify-content:center;margin-bottom:20px}#qr-code{background:#fff;padding:12px;border-radius:12px;display:inline-block}#qr-code canvas{display:block}.amount-display{display:flex;align-items:baseline;justify-content:center;gap:8px;margin-bottom:4px}.amount-value{font-size:32px;font-weight:900;letter-spacing:-.02em;color:var(--text-primary)}.amount-label{font-size:16px;font-weight:700;color:var(--accent)}.fiat-amount{font-size:14px;color:var(--text-secondary);margin-bottom:24px}.address-container{text-align:left;margin-bottom:20px}.address-container label{display:block;font-size:12px;font-weight:600;color:var(--text-secondary);margin-bottom:6px;text-transform:uppercase;letter-spacing:.08em}.address-box{display:flex;align-items:center;gap:8px;background:var(--bg);border:1px solid var(--border);border-radius:8px;padding:10px 12px}.address-box code{flex:1;font-size:11px;font-family:monospace;color:var(--text-primary);word-break:break-all;line-height:1.4}.copy-btn{flex-shrink:0;background:none;border:none;color:var(--text-secondary);cursor:pointer;padding:4px;border-radius:4px;transition:color .15s,background .15s}.copy-btn:hover{color:var(--accent);background:var(--accent-dim)}.copy-btn.copied{color:var(--success)}.status-bar{display:flex;align-items:center;justify-content:center;gap:8px;padding:12px 16px;background:var(--accent-dim);border-radius:8px;margin-bottom:12px}.status-icon{font-size:18px}.status-text{font-size:14px;font-weight:600;color:var(--text-primary)}.status-bar.confirming{background:#f59e0b24}.status-bar.completed{background:#10b98124}.countdown{font-size:13px;color:var(--text-tertiary)}.success-icon{width:64px;height:64px;background:var(--accent);color:#000;border-radius:50%;display:flex;align-items:center;justify-content:center;font-size:32px;font-weight:900;margin:0 auto 16px;animation:pop .3s ease-out}@keyframes pop{0%{transform:scale(.5);opacity:0}to{transform:scale(1);opacity:1}}.success-detail{color:var(--text-secondary);font-size:14px;margin-top:8px}.expired-icon,.error-icon{font-size:48px;margin-bottom:12px}#expired-state p,#error-state p{color:var(--text-secondary);font-size:14px;margin-top:8px}.checkout-footer{padding:16px 24px;border-top:1px solid var(--border);text-align:center;font-size:12px;color:var(--text-tertiary)}.checkout-footer a{color:var(--accent);text-decoration:none}.checkout-footer a:hover{text-decoration:underline}.demo-banner{background:var(--accent);color:#000;text-align:center;font-size:12px;font-weight:600;padding:6px 16px;letter-spacing:.02em}.simulate-btn{display:block;width:100%;margin-top:16px;padding:12px 24px;background:transparent;border:1px solid var(--accent);border-radius:10px;color:var(--accent);font-size:14px;font-weight:600;cursor:pointer;transition:all .15s}.simulate-btn:hover{background:var(--accent-dim)}.simulate-btn:disabled{opacity:.5;cursor:not-allowed}.hidden{display:none!important}