/* 全局变量定义 */
:root {
    --primary-color: #2563eb;
    --primary-dark: #1d4ed8;
    --secondary-color: #f3f4f6;
    --text-color: #1f2937;
    --text-light: #6b7280;
    --bg-white: #ffffff;
    --bg-light: #f9fafb;
    --security-color: #059669; /* 绿色，代表安全 */
    --nav-height: 64px;
    --border-radius-sm: 8px;
    --border-radius-md: 12px;
    --border-radius-lg: 16px;
    --shadow-sm: 0 1px 2px 0 rgba(0, 0, 0, 0.05);
    --shadow-md: 0 4px 6px -1px rgba(0, 0, 0, 0.1), 0 2px 4px -1px rgba(0, 0, 0, 0.06);
    --shadow-lg: 0 10px 15px -3px rgba(0, 0, 0, 0.1), 0 4px 6px -2px rgba(0, 0, 0, 0.05);
}

/* 基础重置 */
* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

body {
    font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, "Helvetica Neue", Arial, sans-serif;
    line-height: 1.6;
    color: var(--text-color);
    background-color: var(--bg-white);
    -webkit-font-smoothing: antialiased;
    overflow-x: hidden;
}

a {
    text-decoration: none;
    color: inherit;
}

ul {
    list-style: none;
}

.container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 20px;
}

/* 动画定义 */
@keyframes slideUp {
    from {
        opacity: 0;
        transform: translateY(30px);
    }
    to {
        opacity: 1;
        transform: translateY(0);
    }
}

@keyframes float {
    0% { transform: translateY(0px); }
    50% { transform: translateY(-10px); }
    100% { transform: translateY(0px); }
}

@keyframes fadeIn {
    from { opacity: 0; }
    to { opacity: 1; }
}

/* 动画类 */
.fade-in-up {
    animation: slideUp 0.8s ease-out forwards;
}

.fade-in-delay {
    opacity: 0;
    animation: slideUp 0.8s ease-out 0.3s forwards;
}

.scroll-animate {
    opacity: 0;
    transform: translateY(30px);
    transition: all 0.6s ease-out;
}

.scroll-animate.visible {
    opacity: 1;
    transform: translateY(0);
}

/* 按钮样式 */
.btn-primary, .btn-secondary {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    padding: 12px 32px;
    border-radius: 9999px; /* 全圆角 */
    font-weight: 600;
    transition: all 0.2s ease;
    cursor: pointer;
    font-size: 1rem;
    box-shadow: var(--shadow-sm);
}

.btn-primary {
    background-color: var(--primary-color);
    color: white;
    border: 2px solid transparent;
}

.btn-primary:hover {
    background-color: var(--primary-dark);
    transform: translateY(-2px);
    box-shadow: var(--shadow-md);
}

.btn-secondary {
    background-color: white;
    color: var(--text-color);
    border: 2px solid #e5e7eb;
}

.btn-secondary:hover {
    border-color: var(--text-color);
    transform: translateY(-2px);
    box-shadow: var(--shadow-md);
}

/* 导航栏 */
.navbar {
    height: var(--nav-height);
    background-color: rgba(255, 255, 255, 0.9);
    backdrop-filter: blur(10px);
    position: fixed;
    top: 0;
    width: 100%;
    z-index: 1000;
    box-shadow: var(--shadow-sm);
    transition: transform 0.3s;
}

.navbar .container {
    display: flex;
    justify-content: space-between;
    align-items: center;
    height: 100%;
}

.navbar .logo {
    display: flex;
    align-items: center;
    font-size: 1.25rem;
    font-weight: 700;
    color: var(--primary-color);
}

.navbar .logo img {
    height: 32px;
    margin-right: 10px;
}

.navbar nav ul {
    display: flex;
    align-items: center;
    gap: 30px;
}

.navbar nav a:not(.btn-primary) {
    color: var(--text-color);
    font-size: 0.95rem;
    font-weight: 500;
    transition: color 0.2s;
}

.navbar nav a:not(.btn-primary):hover {
    color: var(--primary-color);
}

.navbar nav .btn-primary {
    padding: 8px 20px;
    font-size: 0.9rem;
}

/* Hero区域 */
.hero {
    padding-top: calc(var(--nav-height) + 80px);
    padding-bottom: 100px;
    background: radial-gradient(circle at top right, #eff6ff 0%, #ffffff 40%);
    overflow: hidden;
}

.hero .container {
    display: flex;
    align-items: center;
    justify-content: space-between;
    gap: 60px;
}

.hero-content {
    flex: 1;
    z-index: 1;
}

.hero-content h1 {
    font-size: 3.5rem;
    line-height: 1.1;
    margin-bottom: 24px;
    color: #111827;
    font-weight: 800;
    letter-spacing: -0.02em;
}

.hero-content p {
    font-size: 1.25rem;
    color: var(--text-light);
    margin-bottom: 30px;
    max-width: 500px;
}

.security-badge-row {
    display: flex;
    gap: 15px;
    margin-bottom: 30px;
    flex-wrap: wrap;
}

.sec-badge {
    display: inline-flex;
    align-items: center;
    font-size: 0.9rem;
    color: var(--security-color);
    background-color: #ecfdf5;
    padding: 6px 12px;
    border-radius: 6px;
    font-weight: 600;
}

.sec-badge svg {
    margin-right: 6px;
    width: 16px;
    height: 16px;
}

.hero-btns {
    display: flex;
    gap: 16px;
    margin-bottom: 40px;
}

/* 统计数据 */
.stats-row {
    display: flex;
    gap: 40px;
    padding-top: 20px;
    border-top: 1px solid #e5e7eb;
}

.stat-item strong {
    display: inline-block;
    font-size: 2rem;
    font-weight: 800;
    color: var(--primary-color);
    line-height: 1;
}

.stat-item span {
    font-size: 1.2rem;
    color: var(--primary-color);
    font-weight: 600;
}

.stat-item small {
    display: block;
    color: var(--text-light);
    font-size: 0.9rem;
    margin-top: 5px;
}


/* 设备展示 */
.hero-image {
    flex: 1;
    display: flex;
    justify-content: center;
    position: relative;
    perspective: 1000px;
}

.device-composition {
    position: relative;
    width: 600px;
    height: 400px;
    display: flex;
    justify-content: center;
    align-items: flex-end;
}

/* 笔记本 Mockup */
.mockup-laptop {
    width: 480px;
    position: absolute;
    left: 0;
    bottom: 0;
    z-index: 1;
    transform: rotateY(5deg);
    transition: transform 0.5s;
}

.mockup-laptop:hover {
    transform: rotateY(0deg) scale(1.02);
}

.mockup-laptop .screen {
    background: #1f2937;
    border-radius: 12px 12px 0 0;
    padding: 8px 8px 0 8px; /* 减少内边距 */
    height: 300px;
    box-shadow: 0 0 0 2px #d1d5db;
    overflow: hidden; /* 防止溢出 */
}

.mockup-laptop .screen .ui-layout-desktop {
    background: white;
    height: 100%;
    border-radius: 4px 4px 0 0;
    display: flex;
    overflow: hidden;
}

.mockup-laptop .base {
    background: #e5e7eb;
    height: 15px;
    border-radius: 0 0 10px 10px;
    position: relative;
}

.mockup-laptop .base::after {
    content: '';
    position: absolute;
    top: 0;
    left: 50%;
    transform: translateX(-50%);
    width: 60px;
    height: 4px;
    background: #9ca3af;
    border-radius: 0 0 4px 4px;
}

/* Desktop UI 具体实现 */
.ui-nav-rail {
    width: 50px;
    background: #1e293b;
    display: flex;
    flex-direction: column;
    align-items: center;
    padding: 15px 0;
    gap: 15px;
}

.nav-icon {
    width: 32px;
    height: 32px;
    border-radius: 8px;
    display: flex;
    align-items: center;
    justify-content: center;
    color: #94a3b8;
    cursor: pointer;
}

.nav-icon.active {
    background: #3b82f6;
    color: white;
}

.nav-spacer { flex: 1; }

.ui-sidebar-list {
    width: 140px;
    background: #f1f5f9;
    border-right: 1px solid #e2e8f0;
    display: flex;
    flex-direction: column;
}

.search-bar-mock {
    height: 28px;
    margin: 10px;
    background: #e2e8f0;
    border-radius: 6px;
}

.contact-item {
    height: 50px;
    padding: 8px 10px;
    display: flex;
    align-items: center;
    gap: 8px;
    border-left: 2px solid transparent;
}

.contact-item.active {
    background: #fff;
    border-left-color: #3b82f6;
}

.contact-item .avatar {
    width: 32px;
    height: 32px;
    border-radius: 50%;
    background: #cbd5e1;
}

.contact-item .avatar.c1 { background: #bfdbfe; }
.contact-item .avatar.c2 { background: #fecaca; }
.contact-item .avatar.c3 { background: #bbf7d0; }

.contact-item .info {
    flex: 1;
    display: flex;
    flex-direction: column;
    gap: 4px;
}

.contact-item .line1 { height: 6px; width: 60%; background: #94a3b8; border-radius: 3px; }
.contact-item .line2 { height: 4px; width: 40%; background: #cbd5e1; border-radius: 2px; }
.contact-item .line2.short { width: 30%; }

.ui-chat-area {
    flex: 1;
    display: flex;
    flex-direction: column;
    background: white;
}

.ui-header {
    height: 48px;
    border-bottom: 1px solid #f1f5f9;
    padding: 0 15px;
    display: flex;
    align-items: center;
    justify-content: space-between;
}

.header-title { font-size: 0.8rem; font-weight: 700; color: #334155; margin-bottom: 2px; }
.header-status { font-size: 0.6rem; color: #16a34a; }
.header-actions { display: flex; gap: 4px; }
.action-dot { width: 4px; height: 4px; background: #cbd5e1; border-radius: 50%; }

.ui-messages {
    flex: 1;
    padding: 15px;
    display: flex;
    flex-direction: column;
    gap: 12px;
    overflow: hidden;
    background: #f8fafc;
}

.msg-bubble {
    display: flex;
    gap: 8px;
    max-width: 80%;
    align-items: flex-end;
}

.msg-bubble.left { align-self: flex-start; }
.msg-bubble.right { align-self: flex-end; flex-direction: row-reverse; }

.msg-avatar { width: 24px; height: 24px; border-radius: 50%; background: #e2e8f0; }
.msg-bubble.right .msg-avatar { display: none; }

.msg-content {
    background: white;
    padding: 8px 12px;
    border-radius: 12px;
    border-bottom-left-radius: 2px;
    box-shadow: 0 1px 2px rgba(0,0,0,0.05);
}

.msg-bubble.right .msg-content {
    background: #eff6ff;
    border-radius: 12px;
    border-bottom-right-radius: 2px;
}

.msg-line { height: 6px; background: #e2e8f0; margin-bottom: 4px; border-radius: 3px; }
.msg-bubble.right .msg-line { background: #bfdbfe; }
.w-60 { width: 80px; }
.w-40 { width: 50px; }
.w-70 { width: 100px; }

.msg-file-mock {
    display: flex;
    align-items: center;
    gap: 8px;
}
.file-icon { width: 20px; height: 24px; background: #e2e8f0; border-radius: 2px; }
.file-info { display: flex; flex-direction: column; gap: 3px; }
.file-name { width: 60px; height: 5px; background: #cbd5e1; border-radius: 2px; }
.file-size { width: 30px; height: 4px; background: #e2e8f0; border-radius: 2px; }

.ui-input-wrapper {
    height: 48px;
    border-top: 1px solid #f1f5f9;
    padding: 8px 12px;
    display: flex;
    align-items: center;
    gap: 8px;
}

.input-icons-left { display: flex; gap: 4px; }
.icon-dot { width: 16px; height: 16px; border-radius: 50%; background: #e2e8f0; }

.input-field-mock {
    flex: 1;
    height: 30px;
    background: #f1f5f9;
    border-radius: 15px;
}

.send-btn-mock {
    width: 28px;
    height: 28px;
    border-radius: 50%;
    background: #3b82f6;
    display: flex;
    align-items: center;
    justify-content: center;
    color: white;
}


/* 手机 Mockup */
.mockup-phone {
    width: 140px;
    height: 280px;
    background: #1f2937;
    border-radius: 20px;
    position: absolute;
    right: 40px;
    bottom: -20px;
    z-index: 2;
    padding: 6px;
    box-shadow: 0 20px 40px rgba(0,0,0,0.3);
    animation: float 6s ease-in-out infinite;
}

.mockup-phone .notch {
    position: absolute;
    top: 6px;
    left: 50%;
    transform: translateX(-50%);
    width: 40px;
    height: 10px;
    background: #1f2937;
    border-radius: 0 0 8px 8px;
    z-index: 3;
}

.mockup-phone .screen {
    background: white;
    width: 100%;
    height: 100%;
    border-radius: 16px;
    overflow: hidden;
    position: relative;
}

.ui-layout-mobile {
    display: flex;
    flex-direction: column;
    height: 100%;
    background: #f8fafc;
}

.mobile-status-bar {
    height: 20px;
    padding: 0 10px;
    display: flex;
    justify-content: space-between;
    align-items: center;
    font-size: 8px;
    color: #334155;
    background: white;
}
.mobile-status-bar .status-icons { display: flex; gap: 2px; }

.mobile-header {
    height: 36px;
    background: white;
    border-bottom: 1px solid #f1f5f9;
    display: flex;
    align-items: center;
    padding: 0 8px;
    font-size: 0.8rem;
    font-weight: 600;
    justify-content: space-between;
}
.mobile-header span { flex: 1; text-align: center; margin-right: 12px; }
.avatar-sm { width: 20px; height: 20px; border-radius: 50%; background: #cbd5e1; }

.mobile-msgs { padding: 10px; gap: 8px; }

.msg-content.simple {
    width: 60px; height: 8px; background: #e2e8f0; border-radius: 4px;
}
.msg-content.simple.long { width: 80px; background: #bfdbfe; }
.msg-content.simple.short { width: 40px; }

.mobile-input-bar {
    height: 40px;
    background: white;
    padding: 6px 8px;
    display: flex;
    align-items: center;
    gap: 6px;
}
.input-pill { flex: 1; height: 26px; background: #f1f5f9; border-radius: 13px; }
.send-circle { width: 26px; height: 26px; background: #3b82f6; border-radius: 50%; }

/* 特性区域 */
.features {
    padding: 100px 0;
    background-color: var(--bg-white);
}

.features h2, .download h2, .showcase h2, .security-details h2 {
    text-align: center;
    font-size: 2.25rem;
    margin-bottom: 16px;
    font-weight: 700;
    color: #111827;
}

.feature-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(260px, 1fr));
    gap: 40px;
    margin-top: 60px;
}

.feature-card {
    text-align: left;
    padding: 32px;
    border-radius: var(--border-radius-lg);
    background-color: white;
    border: 1px solid #f3f4f6;
    transition: all 0.3s ease;
}

.feature-card:hover {
    transform: translateY(-5px);
    box-shadow: var(--shadow-lg);
    border-color: transparent;
}

.feature-card .icon {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    width: 64px;
    height: 64px;
    border-radius: 16px;
    background-color: #eff6ff;
    color: var(--primary-color);
    margin-bottom: 24px;
}

/* 安全详情区域 - 新增 */
.security-details {
    padding: 80px 0;
    background-color: #f0fdf4; /* 浅绿色背景 */
}

.sec-header {
    text-align: center;
    max-width: 700px;
    margin: 0 auto 50px;
}

.sec-header p {
    color: var(--text-light);
    font-size: 1.2rem;
    margin-top: 15px;
}

.security-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
    gap: 30px;
    max-width: 1100px;
    margin: 0 auto;
}

.sec-card {
    background: white;
    padding: 40px 30px;
    border-radius: 20px;
    text-align: center;
    transition: all 0.3s ease;
    border: 1px solid rgba(5, 150, 105, 0.1);
    box-shadow: 0 4px 6px -1px rgba(0, 0, 0, 0.05);
}

.sec-card:hover {
    transform: translateY(-5px);
    box-shadow: 0 15px 30px -5px rgba(5, 150, 105, 0.15);
    border-color: rgba(5, 150, 105, 0.2);
}

.sec-icon-wrapper {
    width: 80px;
    height: 80px;
    background-color: #ecfdf5;
    color: var(--security-color);
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    margin: 0 auto 24px;
}

.sec-card h3 {
    font-size: 1.25rem;
    margin-bottom: 16px;
    color: #064e3b;
}

.sec-card p {
    color: #4b5563;
    font-size: 0.95rem;
    line-height: 1.6;
}

/* 产品展示区域 */
.showcase {
    padding: 100px 0;
    background-color: #f8fafc;
}

.showcase-header {
    text-align: center;
    max-width: 700px;
    margin: 0 auto 50px;
}

.showcase-header p {
    color: var(--text-light);
    font-size: 1.2rem;
    margin-top: 15px;
}

.preview-tabs {
    display: flex;
    justify-content: center;
    gap: 10px;
    margin-bottom: 40px;
}

.tab-btn {
    padding: 10px 24px;
    background: transparent;
    border: none;
    border-radius: 20px;
    font-size: 1rem;
    color: var(--text-light);
    cursor: pointer;
    transition: all 0.3s;
}

.tab-btn.active {
    background: white;
    color: var(--primary-color);
    box-shadow: var(--shadow-sm);
    font-weight: 600;
}

.preview-container {
    background: white;
    border-radius: 24px;
    box-shadow: var(--shadow-lg);
    overflow: hidden;
    max-width: 900px;
    margin: 0 auto;
    border: 1px solid #e2e8f0;
}

.preview-content {
    display: none;
    min-height: 400px; /* Adjust height */
}

.preview-content.active {
    display: block;
    animation: fadeIn 0.5s;
}

/* Showcase Mockup Refined - 极简风格优化 */
.preview-mock-ui.refined, .preview-mock-ui.admin {
    display: flex;
    height: 500px;
    border-radius: 20px;
    overflow: hidden;
    background: white;
    box-shadow: 0 20px 40px -10px rgba(0,0,0,0.1); /* 更柔和、大气的阴影 */
    border: 1px solid rgba(0,0,0,0.03); /* 极淡的边框 */
}

/* 复用 Chat Sidebar 样式 */
.mock-sidebar {
    width: 280px;
    background: #fdfdfd; /* 极淡灰白，区分度更低，更融合 */
    border-right: 1px solid #f3f4f6;
    display: flex;
    flex-direction: column;
}

.sidebar-header {
    height: 70px;
    padding: 0 24px;
    display: flex;
    align-items: center;
    justify-content: space-between;
}
.sidebar-title { font-weight: 700; font-size: 1.2rem; color: #1f2937; }
.sidebar-action { font-size: 1.5rem; color: #9ca3af; cursor: pointer; transition: color 0.2s; }
.sidebar-action:hover { color: var(--primary-color); }

.sidebar-list { 
    overflow-y: auto; 
    flex: 1; 
    padding: 10px 16px; /* 增加整体内边距，实现悬浮卡片感 */
    display: flex;
    flex-direction: column;
    gap: 4px;
}

.contact-row {
    padding: 12px 16px;
    display: flex;
    gap: 16px;
    cursor: pointer;
    transition: all 0.2s ease;
    border-radius: 12px; /* 圆角矩形条目 */
}

.contact-row:hover { background: #f3f4f6; }

.contact-row.active { 
    background: #eff6ff; 
    /* 去掉左侧边框，改为整体色块高亮，更现代 */
}

.c-avatar {
    width: 44px; height: 44px; border-radius: 14px; /* 更大的圆角 */
    display: flex; align-items: center; justify-content: center;
    font-weight: 600; font-size: 0.95rem; flex-shrink: 0;
    box-shadow: inset 0 0 0 1px rgba(0,0,0,0.03); /* 微弱内边框增加质感 */
}
.c-info { flex: 1; overflow: hidden; display: flex; flex-direction: column; justify-content: center; }
.c-name { font-weight: 600; font-size: 1rem; color: #374151; margin-bottom: 3px; }
.c-preview { color: #9ca3af; font-size: 0.85rem; white-space: nowrap; overflow: hidden; text-overflow: ellipsis; }

.c-meta { display: flex; flex-direction: column; align-items: flex-end; gap: 6px; justify-content: center; }
.c-time { font-size: 0.75rem; color: #cbd5e1; }
.c-badge { 
    background: #ef4444; 
    color: white; 
    font-size: 0.65rem; 
    min-width: 18px; 
    height: 18px; 
    padding: 0 5px;
    border-radius: 9px; 
    font-weight: 600; 
    display: flex;
    align-items: center;
    justify-content: center;
}

.mock-chat {
    flex: 1;
    display: flex;
    flex-direction: column;
    background: white; /* 纯白背景，更干净 */
}

.chat-header {
    height: 70px;
    background: white;
    /* 去掉明显分割线，仅用极淡阴影或完全留白 */
    border-bottom: 1px solid #f9fafb; 
    padding: 0 32px;
    display: flex;
    align-items: center;
    justify-content: space-between;
}
.chat-user { display: flex; align-items: center; gap: 16px; font-weight: 600; font-size: 1.1rem; color: #111827; }
.c-avatar.small { width: 36px; height: 36px; font-size: 0.85rem; border-radius: 10px; }
.chat-actions { display: flex; gap: 20px; }
.chat-actions svg { cursor: pointer; transition: stroke 0.2s; }
.chat-actions svg:hover { stroke: var(--text-color); }

.chat-messages-area {
    flex: 1;
    padding: 30px 40px; /* 增加留白 */
    display: flex;
    flex-direction: column;
    gap: 24px; /* 增加消息间距 */
    overflow-y: auto;
}

.mock-msg {
    display: flex;
    gap: 16px;
    max-width: 75%; /* 限制宽度，更精致 */
}
.mock-msg.left { align-self: flex-start; }
.mock-msg.right { align-self: flex-end; flex-direction: row-reverse; }

.msg-avatar {
    width: 36px; height: 36px; background: #f1f5f9; border-radius: 12px;
    display: flex; align-items: center; justify-content: center;
    font-size: 0.75rem; color: #64748b; font-weight: 600;
}

.msg-text {
    padding: 14px 20px;
    background: #f8fafc; /* 极淡灰背景 */
    border-radius: 18px;
    border-top-left-radius: 4px; /* 调整圆角逻辑 */
    font-size: 0.95rem;
    line-height: 1.6;
    color: #374151;
    box-shadow: none; /* 去掉阴影，更扁平 */
}
.mock-msg.right .msg-text {
    background: var(--primary-color);
    color: white;
    border-radius: 18px;
    border-top-left-radius: 18px;
    border-top-right-radius: 4px;
    box-shadow: 0 4px 12px rgba(37, 99, 235, 0.15); /* 仅发送方保留轻微投影 */
}

.chat-input-area {
    height: 80px;
    background: white;
    border-top: 1px solid #f9fafb;
    padding: 0 40px;
    display: flex;
    align-items: center;
    gap: 20px;
}
.input-tools { display: flex; gap: 16px; color: #cbd5e1; cursor: pointer; }
.input-tools svg:hover { stroke: #94a3b8; }

.input-fake-box {
    flex: 1;
    height: 46px;
    background: #f9fafb;
    border-radius: 23px; /* 全圆角 */
    display: flex;
    align-items: center;
    padding: 0 24px;
    color: #9ca3af;
    font-size: 0.95rem;
    transition: background 0.2s;
}
.input-fake-box:hover { background: #f3f4f6; }

.send-btn-icon {
    width: 46px; height: 46px; background: var(--primary-color); border-radius: 23px; /* 圆形按钮 */
    display: flex; align-items: center; justify-content: center;
    box-shadow: 0 4px 10px rgba(37, 99, 235, 0.2);
    transition: transform 0.2s, box-shadow 0.2s;
    cursor: pointer;
}
.send-btn-icon:hover { transform: translateY(-1px); box-shadow: 0 6px 14px rgba(37, 99, 235, 0.3); }

/* --- Admin Dashboard Styles --- */

.preview-mock-ui.admin {
    display: flex;
    background: #f8fafc; /* 后台背景色略深 */
}

.admin-sidebar {
    width: 240px;
    background: #111827; /* 深色侧边栏 */
    color: white;
    display: flex;
    flex-direction: column;
}

.admin-brand {
    height: 70px;
    display: flex;
    align-items: center;
    padding: 0 24px;
    gap: 12px;
    border-bottom: 1px solid rgba(255,255,255,0.1);
}

.admin-logo {
    width: 32px; height: 32px; background: var(--primary-color); border-radius: 8px;
}
.admin-brand span { font-weight: 700; font-size: 1.1rem; }

.admin-menu {
    padding: 20px 12px;
    display: flex;
    flex-direction: column;
    gap: 8px;
}

.menu-item {
    display: flex;
    align-items: center;
    gap: 12px;
    padding: 12px 16px;
    border-radius: 8px;
    color: #9ca3af;
    cursor: pointer;
    transition: all 0.2s;
    font-size: 0.95rem;
}

.menu-item:hover { background: rgba(255,255,255,0.05); color: white; }
.menu-item.active { background: var(--primary-color); color: white; box-shadow: 0 4px 12px rgba(37, 99, 235, 0.3); }

.admin-main {
    flex: 1;
    display: flex;
    flex-direction: column;
    overflow: hidden;
}

.admin-header {
    height: 70px;
    background: white;
    border-bottom: 1px solid #e5e7eb;
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 0 32px;
}

.admin-header h3 { font-size: 1.1rem; color: #1f2937; }
.admin-user-profile { display: flex; align-items: center; gap: 10px; }
.admin-avatar { width: 32px; height: 32px; background: #e5e7eb; border-radius: 50%; display: flex; align-items: center; justify-content: center; font-size: 0.8rem; font-weight: bold; }

.admin-dashboard {
    padding: 32px;
    flex: 1;
    overflow-y: auto;
}

.stats-cards {
    display: grid;
    grid-template-columns: repeat(4, 1fr);
    gap: 24px;
    margin-bottom: 32px;
}

.a-card {
    background: white;
    padding: 20px;
    border-radius: 16px;
    box-shadow: 0 2px 5px rgba(0,0,0,0.05);
}

.a-label { font-size: 0.85rem; color: #6b7280; margin-bottom: 8px; }
.a-value { font-size: 1.5rem; font-weight: 700; color: #111827; margin-bottom: 4px; }
.a-trend { font-size: 0.8rem; font-weight: 600; }
.a-trend.up { color: #10b981; }
.a-trend.down { color: #ef4444; }
.a-trend.normal { color: #6b7280; }

.admin-chart-area {
    background: white;
    border-radius: 16px;
    padding: 24px;
    height: 300px;
    box-shadow: 0 2px 5px rgba(0,0,0,0.05);
}

.chart-mock {
    width: 100%;
    height: 100%;
    background: #f8fafc;
    border-radius: 12px;
    position: relative;
    display: flex;
    align-items: flex-end;
    justify-content: space-around;
    padding: 20px 20px 0;
}

.chart-bar {
    width: 8%;
    background: #cbd5e1;
    border-radius: 6px 6px 0 0;
    transition: height 0.5s ease;
}

.chart-bar.active { background: var(--primary-color); }

/* 下载区域 */
.download {
    padding: 100px 0;
    background-color: var(--bg-white);
    border-top: 1px solid #f3f4f6;
}

.download .subtitle {
    text-align: center;
    color: var(--text-light);
    margin-top: -5px;
    margin-bottom: 60px;
    font-size: 1.1rem;
}

.download-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(340px, 1fr));
    gap: 40px;
    max-width: 1000px;
    margin: 0 auto;
}

.download-card {
    background: white;
    padding: 48px;
    border-radius: 24px;
    box-shadow: var(--shadow-md);
    text-align: center;
    border: 1px solid rgba(0,0,0,0.02);
    transition: transform 0.3s ease;
}

.download-card:hover {
    transform: translateY(-2px);
    box-shadow: var(--shadow-lg);
}

.download-card h3 {
    margin-bottom: 32px;
    font-size: 1.5rem;
    font-weight: 700;
}

.platform-links {
    display: flex;
    flex-direction: column;
    gap: 16px;
}

.dl-btn {
    display: flex;
    align-items: center;
    justify-content: center;
    padding: 16px;
    border: 1px solid #e5e7eb;
    border-radius: 12px;
    font-weight: 600;
    color: #374151;
    transition: all 0.2s;
    background-color: white;
}

.dl-btn:hover {
    border-color: var(--primary-color);
    color: var(--primary-color);
    background-color: #eff6ff;
    transform: scale(1.02);
}

.dl-btn .icon {
    margin-right: 12px;
    display: flex;
    align-items: center;
}

.dl-btn .icon svg {
    width: 20px;
    height: 20px;
}

/* 响应式适配 */
@media (max-width: 992px) {
    .hero .container {
        flex-direction: column;
        text-align: center;
        gap: 60px;
    }
    
    .hero-content p {
        margin-left: auto;
        margin-right: auto;
    }

    .security-badge-row {
        justify-content: center;
    }

    .hero-btns {
        justify-content: center;
    }
    
    .stats-row {
        justify-content: center;
    }
}

@media (max-width: 768px) {
    :root {
        --nav-height: 56px;
    }

    .navbar .container {
        padding: 0 16px;
    }
    
    .navbar .logo img {
        height: 28px;
    }
    
    .navbar nav {
        display: none; /* 后续可以添加汉堡菜单，暂时隐藏以简化移动端 */
    }
    
    .navbar nav ul {
        /* 如果要显示菜单，需要做成下拉或覆盖层 */
        display: none;
    }
    
    /* 移动端保留 "Web版登录" 按钮，通过绝对定位或其他方式显示？ 
       或者简单起见，只保留 Logo 和一个 CTA 按钮
    */
    .navbar .container {
        justify-content: center; /* Logo 居中 */
    }

    .hero {
        padding-top: 100px;
        padding-bottom: 40px;
    }

    .hero-content h1 {
        font-size: 2.2rem;
        margin-bottom: 16px;
    }
    
    .hero-content p {
        font-size: 1rem;
        margin-bottom: 30px;
    }
    
    .hero-btns {
        flex-direction: column;
        gap: 12px;
        width: 100%;
        max-width: 300px;
        margin: 0 auto 30px;
    }
    
    .btn-primary, .btn-secondary {
        width: 100%;
        padding: 10px 20px;
    }

    .stats-row {
        flex-wrap: wrap;
        gap: 24px;
        justify-content: space-around;
        padding-top: 30px;
    }
    
    .stat-item strong {
        font-size: 1.5rem;
    }
    
    .stat-item small {
        font-size: 0.8rem;
    }

    /* 移动端优化设备展示：只显示手机或大幅缩小 */
    .device-composition {
        width: 100%;
        max-width: 320px;
        height: 240px;
        margin: 0 auto;
        transform: scale(0.9);
        transform-origin: bottom center;
    }
    
    .mockup-laptop {
        /* 移动端隐藏笔记本，专注于移动端展示，或者缩小 */
        display: none; 
    }
    
    .mockup-phone {
        /* 居中显示手机 */
        position: relative;
        right: auto;
        bottom: auto;
        width: 160px;
        height: 320px;
        margin: 0 auto;
        transform: translateY(-40px); /* 向上提一点 */
        box-shadow: 0 15px 30px rgba(0,0,0,0.2);
    }
    
    .features {
        padding: 60px 0;
    }
    
    .feature-card {
        padding: 24px;
    }

    .security-details {
        padding: 50px 0;
    }
    
    .sec-card {
        padding: 30px 20px;
    }

    /* Showcase */
    .showcase {
        padding: 60px 0;
    }
    
    .preview-tabs {
        flex-wrap: wrap;
        gap: 8px;
    }
    
    .tab-btn {
        padding: 8px 16px;
        font-size: 0.9rem;
    }
    
    .preview-container {
        border-radius: 16px;
    }
    
    /* Download */
    .download {
        padding: 60px 0;
    }
    
    .download-card {
        padding: 30px 20px;
    }
    
    .download-grid {
        grid-template-columns: 1fr; /* 单列 */
        gap: 20px;
    }
    
    /* Showcase Mobile 适配 */
    .preview-mock-ui.refined {
        height: auto;
        flex-direction: column;
    }
    
    /* Admin Mobile 适配 */
    .preview-mock-ui.admin {
        display: none !important; /* 移动端暂时隐藏后台演示，或者做适配 */
    }

    .mock-sidebar {
        width: 100%;
        height: 200px;
        border-right: none;
        border-bottom: 1px solid #f1f5f9;
    }
    
    .chat-messages-area {
        height: 300px;
    }

    .stats-cards {
        grid-template-columns: 1fr 1fr;
    }
}