*{box-sizing:border-box}
body{margin:0;font-family:Arial,Helvetica,sans-serif;background:#f4f6f9;color:#1f2937}
header{background:#173b70;color:white;padding:22px 5%;display:flex;justify-content:space-between;align-items:center}
header h1{margin:0 0 6px;font-size:26px}
header p{margin:0;opacity:.85}.clock{font-size:15px}
main{width:92%;max-width:1400px;margin:25px auto}
.stats{display:grid;grid-template-columns:repeat(4,1fr);gap:16px}
.card,.panel{background:white;border-radius:12px;box-shadow:0 3px 12px rgba(0,0,0,.07)}
.card{padding:18px}.card span{display:block;color:#6b7280;font-size:14px}.card strong{display:block;font-size:28px;margin-top:8px;color:#173b70}
.toolbar{display:flex;justify-content:space-between;align-items:center;margin:20px 0}
button{border:0;border-radius:8px;padding:11px 16px;background:#173b70;color:white;cursor:pointer;font-weight:bold}
button:hover{opacity:.9}.secondary{background:#6b7280}.ping{width:100%;margin-top:15px}
.legend{display:flex;gap:16px;font-size:13px}.dot{display:inline-block;width:10px;height:10px;border-radius:50%;margin-right:5px}.online{background:#16a34a}.offline{background:#dc2626}
.workspace{display:grid;grid-template-columns:2fr 1fr;gap:20px}.panel{padding:20px}.panel h2{margin-top:0;font-size:19px}
.topology{position:relative;min-height:590px;border:1px solid #e5e7eb;border-radius:10px;background:linear-gradient(#fff,#f8fafc);overflow:hidden}
.node{position:absolute;width:150px;padding:14px;text-align:center;border-radius:12px;background:white;border:2px solid #173b70;box-shadow:0 4px 10px rgba(0,0,0,.12);z-index:2}
.node .icon{font-size:28px}.node strong{display:block;margin-top:4px;font-size:14px}.node small{color:#6b7280}
.node.online{border-color:#16a34a}.node.offline{border-color:#dc2626}
.node button{margin-top:8px;padding:5px 8px;font-size:11px;background:#dc2626}
.connection{position:absolute;height:4px;background:#3b82f6;transform-origin:0 50%;z-index:1;border-radius:5px}
#deviceList{display:flex;flex-direction:column;gap:8px}.device-row{border:1px solid #e5e7eb;border-radius:8px;padding:10px;font-size:13px;display:flex;justify-content:space-between}
.status{font-weight:bold}.status.on{color:#16a34a}.status.off{color:#dc2626}
.internet-status{display:flex;gap:12px;align-items:center;background:#f0fdf4;padding:12px;border-radius:8px}.internet-icon{font-size:30px}
.internet-status p{font-size:12px;color:#6b7280;margin:5px 0 0}.ping-result{font-size:13px;margin-top:10px;color:#166534}
footer{text-align:center;padding:25px;color:#6b7280;font-size:13px}
@media(max-width:900px){.stats{grid-template-columns:repeat(2,1fr)}.workspace{grid-template-columns:1fr}}
@media(max-width:600px){.stats{grid-template-columns:1fr}.toolbar{flex-direction:column;gap:12px;align-items:flex-start}}