style: 访客3列网格，管理员2列，统一Material卡片

web/src/views/MachineList.vue

@@ -553,20 +553,23 @@ function formatTime(t) {
 
 .cards-grid {
   display: grid;
-  grid-template-columns: repeat(2, 1fr);
-  gap: 20px;
+  grid-template-columns: repeat(3, 1fr);
+  gap: 16px;
 }
-@media (max-width: 900px) {
+@media (max-width: 1200px) {
+  .cards-grid { grid-template-columns: repeat(2, 1fr); }
+}
+@media (max-width: 768px) {
   .cards-grid { grid-template-columns: 1fr; }
 }
 
 /* ─── Material Design 访客卡片 ─── */
 .material-card {
   position: relative;
-  border-radius: 16px;
+  border-radius: 12px;
   border: 1px solid var(--border);
-  padding: 16px;
-  min-height: 180px;
+  padding: 12px 14px;
+  min-height: 140px;
   cursor: default;
   transition: all 0.2s ease;
   overflow: hidden;
@@ -578,7 +581,7 @@ function formatTime(t) {
   border-color: var(--border-strong);
 }
 .material-card.offline-card {
-  opacity: 0.6;
+  opacity: 0.55;
 }
 
 .material-content {
@@ -591,18 +594,18 @@ function formatTime(t) {
   display: flex;
   align-items: center;
   justify-content: space-between;
-  margin-bottom: 10px;
+  margin-bottom: 6px;
 }
 
 .status-indicator {
   display: flex;
   align-items: center;
-  gap: 6px;
+  gap: 4px;
 }
 
 .status-dot {
-  width: 8px;
-  height: 8px;
+  width: 6px;
+  height: 6px;
   border-radius: 50%;
   display: inline-block;
   position: relative;
@@ -618,43 +621,44 @@ function formatTime(t) {
 
 @keyframes pulse-ring {
   0% { box-shadow: 0 0 0 0 rgba(76, 175, 80, 0.4); }
-  70% { box-shadow: 0 0 0 6px rgba(76, 175, 80, 0); }
+  70% { box-shadow: 0 0 0 5px rgba(76, 175, 80, 0); }
   100% { box-shadow: 0 0 0 0 rgba(76, 175, 80, 0); }
 }
 
 .status-text {
-  font-size: 12px;
+  font-size: 11px;
   font-weight: 600;
 }
 .status-text.online { color: var(--success); }
 .status-text.offline { color: var(--text-muted); }
 
 .material-ip {
-  font-size: 11px;
+  font-size: 10px;
   font-weight: 500;
   color: var(--text-muted);
   font-family: 'JetBrains Mono', monospace;
 }
 
 .material-hostname {
-  font-size: 15px;
+  font-size: 14px;
   font-weight: 700;
   color: var(--text-primary);
-  margin-bottom: 4px;
+  margin-bottom: 2px;
   line-height: 1.3;
 }
 
 .material-os {
   display: flex;
   align-items: center;
-  gap: 6px;
-  font-size: 12px;
+  gap: 5px;
+  font-size: 11px;
   color: var(--text-secondary);
-  margin-bottom: 12px;
+  margin-bottom: 8px;
+  flex-wrap: wrap;
 }
 .os-dot {
-  width: 6px;
-  height: 6px;
+  width: 5px;
+  height: 5px;
   border-radius: 50%;
   flex-shrink: 0;
 }
@@ -662,14 +666,14 @@ function formatTime(t) {
 .material-progress-list {
   display: flex;
   flex-direction: column;
-  gap: 8px;
+  gap: 5px;
   margin-top: auto;
 }
 
 .progress-item {
   display: flex;
   flex-direction: column;
-  gap: 3px;
+  gap: 2px;
 }
 
 .progress-label-row {
@@ -679,13 +683,13 @@ function formatTime(t) {
 }
 
 .progress-label {
-  font-size: 11px;
+  font-size: 10px;
   font-weight: 500;
   color: var(--text-muted);
 }
 
 .progress-value {
-  font-size: 12px;
+  font-size: 11px;
   font-weight: 700;
   font-variant-numeric: tabular-nums;
   color: var(--text-primary);
@@ -696,7 +700,7 @@ function formatTime(t) {
 
 .progress-track {
   width: 100%;
-  height: 4px;
+  height: 3px;
   border-radius: 2px;
   background: var(--border);
   overflow: hidden;
@@ -708,6 +712,22 @@ function formatTime(t) {
   transition: width 0.6s ease;
 }
 
+.material-card.admin-card {
+  cursor: pointer;
+}
+.material-card.admin-card:hover {
+  transform: translateY(-3px);
+  box-shadow: var(--shadow-lg);
+  border-color: var(--border-strong);
+}
+
+.material-extra {
+  margin-top: 8px;
+  display: flex;
+  flex-direction: column;
+  gap: 5px;
+}
+
 /* ─── 管理员卡片（保持原有） ─── */
 .server-card {
   position: relative;