diff --git a/frontend/src/components/DiskSpacePopup.vue b/frontend/src/components/DiskSpacePopup.vue
new file mode 100644
index 0000000..e54ff95
--- /dev/null
+++ b/frontend/src/components/DiskSpacePopup.vue
@@ -0,0 +1,370 @@
+<template>
+  <div class="disk-space-container" ref="containerRef">
+    <div
+      class="disk-space-widget"
+      :class="{ expanded: isExpanded }"
+      :style="widgetStyle"
+    >
+      <svg viewBox="0 0 150 150" class="pie-svg" preserveAspectRatio="xMidYMid meet">
+      <defs>
+        <filter id="pieShadow" x="-50%" y="-50%" width="200%" height="200%">
+          <feDropShadow dx="0" dy="4" stdDeviation="8" flood-color="rgba(0,0,0,0.4)" />
+        </filter>
+        <radialGradient id="storageGradient" cx="30%" cy="30%" r="70%">
+          <stop offset="0%" stop-color="#93e" />
+          <stop offset="100%" stop-color="#82d" />
+        </radialGradient>
+        <radialGradient id="otherGradient" cx="30%" cy="30%" r="70%">
+          <stop offset="0%" stop-color="#d9f" />
+          <stop offset="100%" stop-color="#c8e" />
+        </radialGradient>
+        <radialGradient id="highlightOverlay" cx="35%" cy="35%" r="65%">
+          <stop offset="0%" stop-color="rgba(255,255,255,0.15)" />
+          <stop offset="60%" stop-color="rgba(255,255,255,0)" />
+          <stop offset="100%" stop-color="rgba(0,0,0,0.08)" />
+        </radialGradient>
+      </defs>
+
+      <g :filter="isExpanded ? 'url(#pieShadow)' : 'none'">
+        <circle :r="pieRadius" :cx="pieCx" :cy="pieCy" fill="url(#otherGradient)" />
+        <circle :r="pieRadius/2" :cx="pieCx" :cy="pieCy" fill="transparent" :stroke="freeColor" :stroke-width="pieRadius" :stroke-dasharray="pieFreeDash" :stroke-dashoffset="pieFreeOffsetVal" :transform="`rotate(-90 ${pieCx} ${pieCy})`" />
+        <circle :r="pieRadius/2" :cx="pieCx" :cy="pieCy" fill="transparent" stroke="url(#storageGradient)" :stroke-width="pieRadius" :stroke-dasharray="pieStorageDash" :transform="`rotate(-90 ${pieCx} ${pieCy})`" />
+        <circle :r="pieRadius" :cx="pieCx" :cy="pieCy" fill="url(#highlightOverlay)" />
+        <circle :r="pieRadius * 0.22" :cx="pieCx" :cy="pieCy" fill="#000" />
+        <text :x="pieCx" :y="pieCy" dy="0.35em" class="pie-center-label" text-anchor="middle" :style="{ opacity: labelsOpacity }">GB</text>
+        <circle :r="pieRadius" :cx="pieCx" :cy="pieCy" fill="transparent" class="pie-hitarea" @click="handleClick" />
+      </g>
+
+      <g class="pie-labels" :style="{ opacity: labelsOpacity }">
+        <text :x="storageInnerPos.x" :y="storageInnerPos.y" class="pie-label-inner" :text-anchor="getSizeAnchor(sectorInfo.storage.angle)" dominant-baseline="middle" :transform="`rotate(${getSizeRotation(sectorInfo.storage.angle)} ${storageInnerPos.x} ${storageInnerPos.y})`">{{ fmtSize(store.space.storage, sectorInfo.storage.angle) }}</text>
+        <text :x="freeInnerPos.x" :y="freeInnerPos.y" class="pie-label-inner" :text-anchor="getSizeAnchor(sectorInfo.free.angle)" dominant-baseline="middle" :transform="`rotate(${getSizeRotation(sectorInfo.free.angle)} ${freeInnerPos.x} ${freeInnerPos.y})`">{{ fmtSize(store.space.free, sectorInfo.free.angle) }}</text>
+        <text :x="otherInnerPos.x" :y="otherInnerPos.y" class="pie-label-inner" :text-anchor="getSizeAnchor(sectorInfo.other.angle)" dominant-baseline="middle" :transform="`rotate(${getSizeRotation(sectorInfo.other.angle)} ${otherInnerPos.x} ${otherInnerPos.y})`">{{ fmtSize(store.space.usage - store.space.storage, sectorInfo.other.angle) }}</text>
+
+        <defs>
+          <path :id="storageLabelPath.id" :d="storageLabelPath.d" fill="none" />
+          <path :id="freeLabelPath.id" :d="freeLabelPath.d" fill="none" />
+          <path :id="otherLabelPath.id" :d="otherLabelPath.d" fill="none" />
+        </defs>
+
+        <text class="pie-label-sub">
+          <textPath :href="'#' + storageLabelPath.id" startOffset="50%" text-anchor="middle" dominant-baseline="middle">{{ storageName }}</textPath>
+        </text>
+        <text class="pie-label-sub">
+          <textPath :href="'#' + freeLabelPath.id" startOffset="50%" text-anchor="middle" dominant-baseline="middle">free</textPath>
+        </text>
+        <text class="pie-label-sub">
+          <textPath :href="'#' + otherLabelPath.id" startOffset="50%" text-anchor="middle" dominant-baseline="middle">other</textPath>
+        </text>
+      </g>
+    </svg>
+    </div>
+  </div>
+</template>
+
+<script setup lang="ts">
+import { ref, computed, onMounted, onUnmounted } from 'vue'
+import { useMainStore } from '@/stores/main'
+
+const store = useMainStore()
+const containerRef = ref<HTMLDivElement | null>(null)
+
+const isExpanded = ref(false)
+const animProgress = ref(0)
+const labelsOpacity = ref(0)
+let animationFrame: number | null = null
+
+const BASE_SIZE = 48
+const EXPANDED_SCALE = 320 / 48
+const containerPos = ref({ top: 0, left: 0 })
+
+const formatGB = (bytes: number) => {
+  const gb = bytes / (1024 * 1024 * 1024)
+  return gb < 10 ? gb.toFixed(1) : `${Math.round(gb)}`
+}
+
+// Add dot suffix for ambiguous angles (within 15° of horizontal) on numbers that look same upside down
+const fmtSize = (bytes: number, angle: number) => {
+  const s = formatGB(bytes)
+  const a = Math.abs(angle % 180)
+  return (Math.min(a, 180 - a) < 15 && /^[0689]+$/.test(s)) ? `${s}.` : s
+}
+
+const truncateLabel = (name: string, maxLen = 10): string => {
+  if (name.length <= maxLen) return name
+  const parts = name.split(/[\s\-_.,;:!?()\[\]{}]+/)
+  if (parts[0] && parts[0].length <= maxLen) return parts[0]
+  return name.slice(0, maxLen - 1) + '…'
+}
+
+const storageName = computed(() => truncateLabel(store.server.name || 'stored'))
+
+const pieCx = 75
+const pieCy = 75
+const pieRadius = 55
+const CIRC = Math.PI * pieRadius
+
+const pieStorageDash = computed(() => {
+  const s = store.space
+  if (!s.disk) return `0 ${CIRC}`
+  return `${(s.storage / s.disk) * CIRC} ${CIRC}`
+})
+
+const pieFreeDash = computed(() => {
+  const s = store.space
+  if (!s.disk) return `0 ${CIRC}`
+  return `${(s.free / s.disk) * CIRC} ${CIRC}`
+})
+
+const pieFreeOffsetVal = computed(() => {
+  const s = store.space
+  if (!s.disk) return 0
+  return -(s.storage / s.disk) * CIRC
+})
+
+const freeColor = computed(() => {
+  const s = store.space
+  if (!s.disk) return '#6c6'
+  const freePct = s.free / s.disk
+  if (freePct > 0.25) return '#5b5'
+  if (freePct > 0.10) return '#db3'
+  return '#d44'
+})
+
+const PIE_RADIUS = 55
+const LABEL_RADIUS = 62
+
+const getPoint = (angle: number, radius: number) => {
+  const rad = (angle - 90) * Math.PI / 180
+  return { x: pieCx + radius * Math.cos(rad), y: pieCy + radius * Math.sin(rad) }
+}
+
+const sectorInfo = computed(() => {
+  const s = store.space
+  if (!s.disk) return {
+    storage: { angle: 45, pct: 0.25 },
+    free: { angle: 180, pct: 0.5 },
+    other: { angle: 270, pct: 0.25 }
+  }
+
+  const storagePct = s.storage / s.disk
+  const freePct = s.free / s.disk
+  const otherPct = (s.usage - s.storage) / s.disk
+
+  const storageAngle = storagePct * 180  // midpoint of storage sector
+  const freeStart = storagePct * 360
+  const freeAngle = freeStart + freePct * 180
+  const otherStart = (storagePct + freePct) * 360
+  const otherAngle = otherStart + otherPct * 180
+
+  return {
+    storage: { angle: storageAngle, pct: storagePct },
+    free: { angle: freeAngle, pct: freePct },
+    other: { angle: otherAngle, pct: otherPct }
+  }
+})
+
+const rawAngles = computed(() => ({
+  storage: sectorInfo.value.storage.angle,
+  free: sectorInfo.value.free.angle,
+  other: sectorInfo.value.other.angle
+}))
+
+const getSizeRotation = (angle: number) => angle < 180 ? angle - 90 : angle + 90
+const getSizeAnchor = (angle: number) => angle < 180 ? 'end' : 'start'
+
+const INNER_LABEL_RADIUS = PIE_RADIUS * 0.95
+const storageInnerPos = computed(() => getPoint(sectorInfo.value.storage.angle, INNER_LABEL_RADIUS))
+const freeInnerPos = computed(() => getPoint(sectorInfo.value.free.angle, INNER_LABEL_RADIUS))
+const otherInnerPos = computed(() => getPoint(sectorInfo.value.other.angle, INNER_LABEL_RADIUS))
+
+// Collision avoidance for curved name labels
+const labelLengths = computed(() => ({
+  storage: storageName.value.length,
+  free: 4,
+  other: 5
+}))
+
+const getGapForPair = (len1: number, len2: number) => {
+  return 35 + Math.max(0, len1 + len2 - 8) * 2.5
+}
+
+const adjustedLabelAngles = computed(() => {
+  const angles = rawAngles.value
+  const lens = labelLengths.value
+  const labels = [
+    { id: 'storage', angle: angles.storage, len: lens.storage },
+    { id: 'free', angle: angles.free, len: lens.free },
+    { id: 'other', angle: angles.other, len: lens.other }
+  ]
+  labels.sort((a, b) => a.angle - b.angle)
+
+  for (let iterations = 0; iterations < 15; iterations++) {
+    let moved = false
+    for (let i = 0; i < labels.length; i++) {
+      const current = labels[i]!
+      const next = labels[(i + 1) % labels.length]!
+      let angleDiff = next.angle - current.angle
+      if (angleDiff < 0) angleDiff += 360
+      const requiredGap = getGapForPair(current.len, next.len)
+      if (angleDiff < requiredGap) {
+        const push = (requiredGap - angleDiff) / 2
+        current.angle = (current.angle - push + 360) % 360
+        next.angle = (next.angle + push) % 360
+        moved = true
+      }
+    }
+    if (!moved) break
+  }
+
+  const result: Record<string, number> = {}
+  for (const l of labels) result[l.id] = l.angle
+  return result
+})
+
+// Arc path for curved text labels (CW for top half, CCW for bottom half)
+const createArcPath = (centerAngle: number, id: string) => {
+  const radius = LABEL_RADIUS
+  const arcSpan = 60
+  const isBottom = centerAngle > 90 && centerAngle <= 270
+  const startAngle = isBottom ? centerAngle + arcSpan / 2 : centerAngle - arcSpan / 2
+  const endAngle = isBottom ? centerAngle - arcSpan / 2 : centerAngle + arcSpan / 2
+  const start = getPoint(startAngle, radius)
+  const end = getPoint(endAngle, radius)
+  const sweep = isBottom ? 0 : 1
+  return {
+    id: `label-path-${id}`,
+    d: `M ${start.x} ${start.y} A ${radius} ${radius} 0 0 ${sweep} ${end.x} ${end.y}`
+  }
+}
+
+const storageLabelPath = computed(() => createArcPath(adjustedLabelAngles.value.storage!, 'storage'))
+const freeLabelPath = computed(() => createArcPath(adjustedLabelAngles.value.free!, 'free'))
+const otherLabelPath = computed(() => createArcPath(adjustedLabelAngles.value.other!, 'other'))
+
+const widgetStyle = computed(() => {
+  const t = animProgress.value
+  const eased = 1 - Math.pow(1 - t, 3)
+  const scale = 1 + (EXPANDED_SCALE - 1) * eased
+  const expandedTranslateX = window.innerWidth - containerPos.value.left - BASE_SIZE
+  const expandedTranslateY = -containerPos.value.top
+  const translateX = expandedTranslateX * eased
+  const translateY = expandedTranslateY * eased
+  return {
+    transform: `translate(${translateX}px, ${translateY}px) scale(${scale})`,
+    transformOrigin: 'top right',
+    zIndex: isExpanded.value ? 1001 : 'auto',
+  }
+})
+
+const handleClick = () => isExpanded.value ? collapse() : expand()
+
+const animate = (startTime: number, duration: number, from: number, to: number, onComplete?: () => void) => {
+  const tick = (now: number) => {
+    const elapsed = now - startTime
+    const progress = Math.min(elapsed / duration, 1)
+    animProgress.value = from + (to - from) * progress
+    labelsOpacity.value = to > from ? progress : 1 - progress
+    if (progress < 1) {
+      animationFrame = requestAnimationFrame(tick)
+    } else {
+      animationFrame = null
+      onComplete?.()
+    }
+  }
+  animationFrame = requestAnimationFrame(tick)
+}
+
+const expand = () => {
+  if (animationFrame) cancelAnimationFrame(animationFrame)
+  if (containerRef.value) {
+    const rect = containerRef.value.getBoundingClientRect()
+    containerPos.value = { top: rect.top, left: rect.left }
+  }
+  isExpanded.value = true
+  animate(performance.now(), 300, 0, 1)
+}
+
+const collapse = () => {
+  if (animationFrame) cancelAnimationFrame(animationFrame)
+  if (containerRef.value) {
+    const rect = containerRef.value.getBoundingClientRect()
+    containerPos.value = { top: rect.top, left: rect.left }
+  }
+  animate(performance.now(), 300, 1, 0, () => {
+    isExpanded.value = false
+  })
+}
+
+const handleKeydown = (e: KeyboardEvent) => {
+  if (e.key === 'Escape' && isExpanded.value) collapse()
+}
+
+onMounted(() => {
+  document.addEventListener('keydown', handleKeydown)
+})
+
+onUnmounted(() => {
+  document.removeEventListener('keydown', handleKeydown)
+  if (animationFrame) cancelAnimationFrame(animationFrame)
+})
+</script>
+
+<style scoped>
+.disk-space-container {
+  position: relative;
+  width: 3em;
+  height: 3em;
+}
+
+.disk-space-widget {
+  position: absolute;
+  top: 0;
+  left: 0;
+  width: 3em;
+  height: 3em;
+  cursor: pointer;
+  will-change: transform;
+}
+
+.disk-space-widget.expanded {
+  pointer-events: none;
+}
+
+.pie-svg {
+  width: 100%;
+  height: 100%;
+  overflow: visible;
+  pointer-events: none;
+}
+
+.pie-hitarea {
+  pointer-events: auto;
+  cursor: pointer;
+}
+
+.pie-label-inner {
+  fill: #fff;
+  font-size: 12px;
+  font-weight: 700;
+  stroke: #000;
+  stroke-width: 0.5px;
+  paint-order: stroke fill;
+}
+
+.pie-center-label {
+  fill: #fff;
+  font-size: 10px;
+  font-weight: 600;
+}
+
+.pie-label-sub {
+  fill: #fff;
+  font-size: 14px;
+  font-weight: 600;
+  font-variant: small-caps;
+  text-transform: lowercase;
+  stroke: #000;
+  stroke-width: 1px;
+  paint-order: stroke fill;
+}
+</style>
diff --git a/frontend/src/components/HeaderMain.vue b/frontend/src/components/HeaderMain.vue
index a52ed4c..cc58620 100644
--- a/frontend/src/components/HeaderMain.vue
+++ b/frontend/src/components/HeaderMain.vue
@@ -20,40 +20,7 @@
       <span v-if="!query" class="search-hint" @click="focusSearch">/</span>
     </div>
     <div class="spacer smallgap"></div>
-    <div v-if="store.space.disk" class="disk-space"
-      @mouseenter="diskTooltip?.startHover"
-      @mousemove="diskTooltip?.updatePosition"
-      @mouseleave="diskTooltip?.endHover"
-    >
-      <svg viewBox="0 0 32 32" class="pie-mini">
-        <!-- Base: 'other' usage (light purple - appears on left, before 12 o'clock) -->
-        <circle r="16" cx="16" cy="16" fill="#c8e" />
-        <!-- Middle ring: free space (dynamic color - appears at bottom) -->
-        <circle r="8" cx="16" cy="16" fill="transparent" :stroke="freeColor" stroke-width="16" :stroke-dasharray="pieFree" :stroke-dashoffset="pieFreeOffset" transform="rotate(-90 16 16)" />
-        <!-- Top ring: storage (deep purple - appears on right after 12 o'clock) -->
-        <circle r="8" cx="16" cy="16" fill="transparent" stroke="#82d" stroke-width="16" :stroke-dasharray="pieStorage" transform="rotate(-90 16 16)" />
-        <!-- Subtle inner circle for depth -->
-        <circle r="2" cx="16" cy="16" fill="rgba(255,255,255,0.2)" />
-      </svg>
-      <CursorTooltip ref="diskTooltip" text="Disk space">
-        <div class="disk-tooltip">
-          <svg viewBox="0 0 160 80" width="160" height="80" class="pie-tooltip">
-            <!-- Pie chart centered at 40,40 -->
-            <circle r="32" cx="40" cy="40" fill="#c8e" />
-            <circle r="16" cx="40" cy="40" fill="transparent" :stroke="freeColor" stroke-width="32" :stroke-dasharray="pieFreeLg" :stroke-dashoffset="pieFreeOffsetLg" transform="rotate(-90 40 40)" />
-            <circle r="16" cx="40" cy="40" fill="transparent" stroke="#82d" stroke-width="32" :stroke-dasharray="pieStorageLg" transform="rotate(-90 40 40)" />
-            <circle r="4" cx="40" cy="40" fill="rgba(255,255,255,0.25)" />
-            <!-- Labels on the right -->
-            <rect x="78" y="10" width="10" height="10" fill="#82d" rx="2"/>
-            <text x="92" y="19" class="pie-label">{{ formatSize(store.space.storage) }} stored</text>
-            <rect x="78" y="30" width="10" height="10" fill="#c8e" rx="2"/>
-            <text x="92" y="39" class="pie-label">{{ formatSize(store.space.usage - store.space.storage) }} other</text>
-            <rect x="78" y="50" width="10" height="10" :fill="freeColor" rx="2"/>
-            <text x="92" y="59" class="pie-label">{{ formatSize(store.space.free) }} free</text>
-          </svg>
-        </div>
-      </CursorTooltip>
-    </div>
+    <DiskSpacePopup v-if="store.space.disk" />
     <SvgButton name="cog" @click="settingsMenu" />
   </nav>
 </template>
@@ -61,74 +28,18 @@
 <script setup lang="ts">
 import { useMainStore } from '@/stores/main'
 import { useSsoAuthStore } from '@/stores/ssoAuth'
-import { ref, nextTick, watchEffect, computed } from 'vue'
+import { ref, nextTick, watchEffect } from 'vue'
 import ContextMenu from '@imengyu/vue3-context-menu'
 import { showAuthIframe } from 'paskia'
 import { resumeWatching } from '@/repositories/WS'
 import router from '@/router';
-import { formatSize } from '@/utils'
-import CursorTooltip from './CursorTooltip.vue'
+import DiskSpacePopup from './DiskSpacePopup.vue'
 
 const store = useMainStore()
 const ssoStore = useSsoAuthStore()
 const search = ref<HTMLInputElement | null>()
-const diskTooltip = ref<InstanceType<typeof CursorTooltip> | null>(null)
 
-const CIRC = 50.27  // 2π×8
-
-// Storage segment (starts at top, -90°)
-const pieStorage = computed(() => {
-  const s = store.space
-  if (!s.disk) return `0 ${CIRC}`
-  const pct = s.storage / s.disk
-  return `${pct * CIRC} ${CIRC}`
-})
-
-// Free segment (starts after storage, goes clockwise to bottom area)
-const pieFree = computed(() => {
-  const s = store.space
-  if (!s.disk) return `0 ${CIRC}`
-  const pct = s.free / s.disk
-  return `${pct * CIRC} ${CIRC}`
-})
-
-const pieFreeOffset = computed(() => {
-  const s = store.space
-  if (!s.disk) return 0
-  // Start after storage segment
-  const storagePct = s.storage / s.disk
-  return -storagePct * CIRC
-})
-
-// Free space color: green when plenty, yellow when moderate, red when low
-const freeColor = computed(() => {
-  const s = store.space
-  if (!s.disk) return '#6c6'
-  const freePct = s.free / s.disk
-  if (freePct > 0.25) return '#5b5'  // Green: > 25% free
-  if (freePct > 0.10) return '#db3'  // Yellow: 10-25% free
-  return '#d44'  // Red: < 10% free
-})
-
-// Large pie for tooltip (circumference = 2π×16 ≈ 100.53)
-const CIRC_LG = 100.53
-const pieStorageLg = computed(() => {
-  const s = store.space
-  if (!s.disk) return `0 ${CIRC_LG}`
-  return `${(s.storage / s.disk) * CIRC_LG} ${CIRC_LG}`
-})
-const pieFreeLg = computed(() => {
-  const s = store.space
-  if (!s.disk) return `0 ${CIRC_LG}`
-  return `${(s.free / s.disk) * CIRC_LG} ${CIRC_LG}`
-})
-const pieFreeOffsetLg = computed(() => {
-  const s = store.space
-  if (!s.disk) return 0
-  return -(s.storage / s.disk) * CIRC_LG
-})
-
-  const props = defineProps<{
+const props = defineProps<{
   path: Array<string>
   query: string
 }>()
@@ -280,23 +191,4 @@ defineExpose({
   cursor: pointer;
   transition: opacity 0.15s ease;
 }
-.disk-space {
-  display: flex;
-  align-items: center;
-  cursor: default;
-}
-.pie-mini {
-  width: 1.4em;
-  height: 1.4em;
-}
-.disk-tooltip {
-  line-height: 1.5;
-}
-.pie-tooltip {
-  display: block;
-}
-.pie-tooltip .pie-label {
-  fill: #fff;
-  font-size: 9px;
-}
 </style>