feat(usage): replace time-range select with custom dropdown

src/pages/UsagePage.module.scss

@@ -44,38 +44,94 @@
   align-items: center;
 }
 
-.select.timeRangeSelect {
+.timeRangeSelect {
+  display: inline-flex;
+  align-items: center;
+  justify-content: space-between;
+  gap: 8px;
   min-width: 164px;
   height: 40px;
-  border-color: var(--border-color);
+  padding: 0 12px;
+  border: 1px solid var(--border-color);
   border-radius: $radius-md;
   background-color: var(--bg-primary);
   box-shadow: var(--shadow);
   color: var(--text-primary);
   font-size: 13px;
   font-weight: 500;
-  padding-right: 34px;
+  cursor: pointer;
   appearance: none;
-  -webkit-appearance: none;
-  -moz-appearance: none;
+  text-align: left;
 
   &:hover {
     border-color: var(--border-hover);
   }
 
   &:focus {
+    outline: none;
+    box-shadow: var(--shadow), 0 0 0 3px rgba(59, 130, 246, 0.15);
+  }
+
+  &[aria-expanded='true'] {
+    border-color: var(--primary-color);
     box-shadow: var(--shadow), 0 0 0 3px rgba(59, 130, 246, 0.15);
   }
 }
 
+.timeRangeSelectedText {
+  overflow: hidden;
+  text-overflow: ellipsis;
+  white-space: nowrap;
+}
+
 .timeRangeSelectIcon {
-  position: absolute;
-  right: 11px;
-  top: 50%;
-  transform: translateY(-50%);
   display: inline-flex;
   color: var(--text-secondary);
-  pointer-events: none;
+  flex-shrink: 0;
+  transition: transform 0.2s ease;
+
+  [aria-expanded='true'] > & {
+    transform: rotate(180deg);
+  }
+}
+
+.timeRangeDropdown {
+  position: absolute;
+  top: calc(100% + 6px);
+  left: 0;
+  right: 0;
+  z-index: 1000;
+  background: var(--bg-primary);
+  border: 1px solid var(--border-color);
+  border-radius: $radius-lg;
+  padding: 6px;
+  box-shadow: var(--shadow-lg);
+  display: flex;
+  flex-direction: column;
+  gap: 4px;
+}
+
+.timeRangeOption {
+  padding: 8px 12px;
+  border-radius: $radius-md;
+  border: 1px solid transparent;
+  background: transparent;
+  color: var(--text-primary);
+  cursor: pointer;
+  text-align: left;
+  font-size: 13px;
+  font-weight: 500;
+  transition: background-color 0.15s ease, border-color 0.15s ease;
+
+  &:hover {
+    background: var(--bg-secondary);
+  }
+}
+
+.timeRangeOptionActive {
+  border-color: rgba(59, 130, 246, 0.5);
+  background: rgba(59, 130, 246, 0.10);
+  font-weight: 600;
 }
 
 .pageTitle {

src/pages/UsagePage.tsx

@@ -1,4 +1,4 @@
-import { useState, useMemo, useCallback, useEffect } from 'react';
+import { useState, useMemo, useCallback, useEffect, useRef } from 'react';
 import { useTranslation } from 'react-i18next';
 import {
   Chart as ChartJS,
@@ -54,6 +54,12 @@ const TIME_RANGE_STORAGE_KEY = 'cli-proxy-usage-time-range-v1';
 const DEFAULT_CHART_LINES = ['all'];
 const DEFAULT_TIME_RANGE: UsageTimeRange = '24h';
 const MAX_CHART_LINES = 9;
+const TIME_RANGE_OPTIONS: ReadonlyArray<{ value: UsageTimeRange; labelKey: string }> = [
+  { value: 'all', labelKey: 'usage_stats.range_all' },
+  { value: '7h', labelKey: 'usage_stats.range_7h' },
+  { value: '24h', labelKey: 'usage_stats.range_24h' },
+  { value: '7d', labelKey: 'usage_stats.range_7d' },
+];
 const HOUR_WINDOW_BY_TIME_RANGE: Record<Exclude<UsageTimeRange, 'all'>, number> = {
   '7h': 7,
   '24h': 24,
@@ -110,6 +116,19 @@ export function UsagePage() {
   const resolvedTheme = useThemeStore((state) => state.resolvedTheme);
   const isDark = resolvedTheme === 'dark';
 
+  // Time range dropdown
+  const [timeRangeOpen, setTimeRangeOpen] = useState(false);
+  const timeRangeRef = useRef<HTMLDivElement | null>(null);
+
+  useEffect(() => {
+    if (!timeRangeOpen) return;
+    const handleClickOutside = (event: MouseEvent) => {
+      if (!timeRangeRef.current?.contains(event.target as Node)) setTimeRangeOpen(false);
+    };
+    document.addEventListener('mousedown', handleClickOutside);
+    return () => document.removeEventListener('mousedown', handleClickOutside);
+  }, [timeRangeOpen]);
+
   // Data hook
   const {
     usage,
@@ -214,20 +233,43 @@ export function UsagePage() {
         <div className={styles.headerActions}>
           <div className={styles.timeRangeGroup}>
             <span className={styles.timeRangeLabel}>{t('usage_stats.range_filter')}</span>
-            <div className={styles.timeRangeSelectWrap}>
-              <select
-                value={timeRange}
-                onChange={(event) => setTimeRange(event.target.value as UsageTimeRange)}
-                className={`${styles.select} ${styles.timeRangeSelect}`}
+            <div className={styles.timeRangeSelectWrap} ref={timeRangeRef}>
+              <button
+                type="button"
+                className={styles.timeRangeSelect}
+                onClick={() => setTimeRangeOpen((prev) => !prev)}
+                aria-haspopup="listbox"
+                aria-expanded={timeRangeOpen}
               >
-                <option value="all">{t('usage_stats.range_all')}</option>
-                <option value="7h">{t('usage_stats.range_7h')}</option>
-                <option value="24h">{t('usage_stats.range_24h')}</option>
-                <option value="7d">{t('usage_stats.range_7d')}</option>
-              </select>
-              <span className={styles.timeRangeSelectIcon} aria-hidden="true">
-                <IconChevronDown size={14} />
-              </span>
+                <span className={styles.timeRangeSelectedText}>
+                  {t(TIME_RANGE_OPTIONS.find((o) => o.value === timeRange)?.labelKey ?? 'usage_stats.range_24h')}
+                </span>
+                <span className={styles.timeRangeSelectIcon} aria-hidden="true">
+                  <IconChevronDown size={14} />
+                </span>
+              </button>
+              {timeRangeOpen && (
+                <div className={styles.timeRangeDropdown} role="listbox" aria-label={t('usage_stats.range_filter')}>
+                  {TIME_RANGE_OPTIONS.map((opt) => {
+                    const active = opt.value === timeRange;
+                    return (
+                      <button
+                        key={opt.value}
+                        type="button"
+                        role="option"
+                        aria-selected={active}
+                        className={`${styles.timeRangeOption} ${active ? styles.timeRangeOptionActive : ''}`}
+                        onClick={() => {
+                          setTimeRange(opt.value);
+                          setTimeRangeOpen(false);
+                        }}
+                      >
+                        {t(opt.labelKey)}
+                      </button>
+                    );
+                  })}
+                </div>
+              )}
             </div>
           </div>
           <Button