/* ===== 全局重置 & 移动端基础 ===== */
* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
    -webkit-tap-highlight-color: transparent;
    font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, Helvetica, Arial, sans-serif;
}

body {
    background: #f5f5f5;
    height: 100vh;
    overflow: hidden;
    display: flex;
    justify-content: center;
    align-items: center;
}

/* 主应用容器 (模拟手机屏幕) */
#app {
    width: 100%;
    max-width: 480px;
    height: 100vh;
    max-height: 850px;
    background: #ffffff;
    box-shadow: 0 0 40px rgba(0, 0, 0, 0.1);
    border-radius: 28px;
    overflow: hidden;
    display: flex;
    flex-direction: column;
    position: relative;
    margin: 0 auto;
    border: 1px solid rgba(255, 255, 255, 0.2);
}

/* 适配全面屏圆角 */
@supports (padding: max(0px)) {
    #app {
        padding-left: max(12px, env(safe-area-inset-left));
        padding-right: max(12px, env(safe-area-inset-right));
        padding-top: max(12px, env(safe-area-inset-top));
        padding-bottom: max(12px, env(safe-area-inset-bottom));
        border-radius: 32px;
    }
}

/* 头部 */
.app-header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 16px 20px 8px 20px;
    background: #ededed;
    border-bottom: 1px solid #d9d9d9;
    flex-shrink: 0;
}

.header-title {
    font-size: 20px;
    font-weight: 600;
    color: #1a1a1a;
}

.header-left i, .header-right i {
    font-size: 20px;
    color: #1a1a1a;
    cursor: pointer;
    padding: 6px;
    border-radius: 50%;
    transition: background 0.2s;
}

.header-left i:active, .header-right i:active {
    background: rgba(0,0,0,0.05);
}

/* 页面容器 */
.page {
    flex: 1;
    overflow-y: auto;
    background: #ffffff;
    display: flex;
    flex-direction: column;
}

.page.active {
    display: flex;
}

/* 聊天列表 */
.chat-list {
    padding: 8px 0;
    flex: 1;
}

.chat-item {
    display: flex;
    align-items: center;
    padding: 14px 20px;
    border-bottom: 1px solid #f0f0f0;
    transition: background 0.15s;
    cursor: pointer;
}

.chat-item:active {
    background: #ececec;
}

.chat-avatar {
    width: 52px;
    height: 52px;
    border-radius: 50%;
    background: #07c160;
    display: flex;
    justify-content: center;
    align-items: center;
    color: white;
    font-size: 22px;
    font-weight: 600;
    margin-right: 14px;
    flex-shrink: 0;
    box-shadow: 0 2px 8px rgba(7, 193, 96, 0.2);
}

.chat-info {
    flex: 1;
    min-width: 0;
}

.chat-name {
    font-size: 17px;
    font-weight: 500;
    color: #1a1a1a;
    margin-bottom: 4px;
}

.chat-preview {
    font-size: 14px;
    color: #999;
    white-space: nowrap;
    overflow: hidden;
    text-overflow: ellipsis;
    max-width: 200px;
}

.chat-time {
    font-size: 12px;
    color: #bbb;
    flex-shrink: 0;
    margin-left: 8px;
    align-self: flex-start;
    margin-top: 4px;
}

/* 聊天对话页 */
.chat-header {
    display: flex;
    align-items: center;
    padding: 12px 16px;
    background: #ededed;
    border-bottom: 1px solid #d9d9d9;
    flex-shrink: 0;
}

.chat-header i {
    font-size: 22px;
    color: #1a1a1a;
    cursor: pointer;
    padding: 6px;
    border-radius: 50%;
}

.chat-header i:active {
    background: rgba(0,0,0,0.05);
}

.chat-header span {
    flex: 1;
    text-align: center;
    font-weight: 600;
    font-size: 18px;
}

.message-area {
    flex: 1;
    padding: 16px 12px;
    overflow-y: auto;
    background: #f7f7f7;
    display: flex;
    flex-direction: column;
    gap: 12px;
}

.message {
    max-width: 75%;
    padding: 10px 14px;
    border-radius: 20px;
    font-size: 16px;
    line-height: 1.4;
    word-break: break-word;
    box-shadow: 0 1px 2px rgba(0,0,0,0.05);
    animation: fadeInUp 0.2s ease;
}

@keyframes fadeInUp {
    from { opacity: 0; transform: translateY(8px); }
    to { opacity: 1; transform: translateY(0); }
}

.message.sent {
    align-self: flex-end;
    background: #95ec69;
    border-bottom-right-radius: 4px;
}

.message.received {
    align-self: flex-start;
    background: #ffffff;
    border-bottom-left-radius: 4px;
    border: 1px solid #e5e5e5;
}

.message-time {
    font-size: 11px;
    color: #aaa;
    margin-top: 4px;
    text-align: right;
}

/* 输入栏 */
.input-bar {
    display: flex;
    align-items: center;
    padding: 8px 12px;
    background: #f7f7f7;
    border-top: 1px solid #e0e0e0;
    flex-shrink: 0;
    gap: 8px;
}

.input-bar i {
    font-size: 24px;
    color: #555;
    cursor: pointer;
    padding: 6px;
}

.input-bar i:active {
    color: #07c160;
}

.input-bar input {
    flex: 1;
    border: none;
    background: #ffffff;
    border-radius: 24px;
    padding: 10px 16px;
    font-size: 16px;
    outline: none;
    border: 1px solid #ddd;
    transition: border 0.2s;
}

.input-bar input:focus {
    border-color: #07c160;
}

#sendBtn {
    background: #07c160;
    border: none;
    color: white;
    width: 44px;
    height: 44px;
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 20px;
    cursor: pointer;
    transition: background 0.2s, transform 0.1s;
    box-shadow: 0 2px 8px rgba(7, 193, 96, 0.3);
}

#sendBtn:active {
    background: #06ad56;
    transform: scale(0.95);
}

/* 底部导航栏 */
.bottom-nav {
    display: flex;
    justify-content: space-around;
    background: #f9f9f9;
    border-top: 1px solid #e0e0e0;
    padding: 6px 0 10px 0;
    flex-shrink: 0;
}

.nav-item {
    display: flex;
    flex-direction: column;
    align-items: center;
    font-size: 12px;
    color: #999;
    cursor: pointer;
    padding: 4px 12px;
    transition: color 0.2s;
}

.nav-item i {
    font-size: 24px;
    margin-bottom: 2px;
}

.nav-item.active {
    color: #07c160;
}

.nav-item:active {
    color: #06ad56;
}

/* 浮动管理按钮 */
.admin-float-btn {
    position: fixed;
    bottom: 100px;
    right: 20px;
    width: 50px;
    height: 50px;
    background: #07c160;
    color: white;
    border-radius: 50%;
    display: flex;
    justify-content: center;
    align-items: center;
    font-size: 24px;
    box-shadow: 0 4px 16px rgba(7, 193, 96, 0.4);
    cursor: pointer;
    z-index: 100;
    transition: transform 0.2s;
}

.admin-float-btn:active {
    transform: scale(0.9);
}

/* ===== 后台管理抽屉 ===== */
.admin-drawer {
    position: fixed;
    top: 0;
    right: -100%;
    width: 320px;
    max-width: 85vw;
    height: 100vh;
    background: #ffffff;
    box-shadow: -6px 0 30px rgba(0,0,0,0.2);
    transition: right 0.3s cubic-bezier(0.22, 1, 0.36, 1);
    z-index: 200;
    display: flex;
    flex-direction: column;
    border-radius: 20px 0 0 20px;
}

.admin-drawer.open {
    right: 0;
}

.admin-header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 20px 20px 12px;
    border-bottom: 1px solid #eee;
    font-size: 18px;
    font-weight: 600;
}

.admin-header i {
    font-size: 22px;
    cursor: pointer;
    padding: 6px;
    color: #555;
}

.admin-body {
    padding: 20px;
    overflow-y: auto;
    flex: 1;
}

.admin-body h3 {
    margin-bottom: 16px;
    color: #1a1a1a;
}

.admin-body input {
    width: 100%;
    padding: 12px 16px;
    margin-bottom: 12px;
    border: 1px solid #ddd;
    border-radius: 12px;
    font-size: 16px;
    outline: none;
}

.admin-body input:focus {
    border-color: #07c160;
}

.admin-btn {
    width: 100%;
    padding: 12px;
    background: #07c160;
    color: white;
    border: none;
    border-radius: 12px;
    font-size: 16px;
    font-weight: 500;
    cursor: pointer;
    transition: background 0.2s;
    margin-bottom: 8px;
}

.admin-btn:active {
    background: #06ad56;
}

.admin-btn.danger {
    background: #e74c3c;
}

.admin-btn.danger:active {
    background: #c0392b;
}

.error-message {
    color: #e74c3c;
    font-size: 14px;
    margin-top: 8px;
}

/* 响应式：小屏手机适配 */
@media (max-width: 420px) {
    #app {
        border-radius: 0;
        max-height: 100vh;
        border: none;
    }
    .admin-float-btn {
        bottom: 80px;
        right: 12px;
        width: 44px;
        height: 44px;
        font-size: 20px;
    }
}

/* 滚动条美化 */
::-webkit-scrollbar {
    width: 4px;
}
::-webkit-scrollbar-track {
    background: transparent;
}
::-webkit-scrollbar-thumb {
    background: #ccc;
    border-radius: 8px;
}
```
```markdown