/* ============================================================
   泽途新邦 - 主样式表
   主题：现代科技蓝紫渐变 + 简洁专业
   ============================================================ */

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

:root {
    /* 品牌色 */
    --primary: #4f7cff;
    --primary-dark: #3a5fd9;
    --secondary: #a55eea;
    --accent: #26de81;
    --orange: #ff9f43;

    /* 中性色 */
    --bg: #ffffff;
    --bg-alt: #f6f8fc;
    --bg-dark: #0f1535;
    --text: #1a2240;
    --text-light: #5a6485;
    --text-muted: #8a93b0;
    --border: #e8ecf5;

    /* 阴影 */
    --shadow-sm: 0 2px 8px rgba(20, 40, 100, 0.06);
    --shadow-md: 0 8px 24px rgba(20, 40, 100, 0.08);
    --shadow-lg: 0 20px 50px rgba(20, 40, 100, 0.12);
    --shadow-primary: 0 12px 30px rgba(79, 124, 255, 0.35);

    /* 尺寸 */
    --radius: 14px;
    --radius-sm: 8px;
    --radius-lg: 24px;
    --container: 1200px;
    --header-h: 72px;
}

html {
    scroll-behavior: smooth;
    scroll-padding-top: var(--header-h);
}

body {
    font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", "PingFang SC",
        "Hiragino Sans GB", "Microsoft YaHei", "Helvetica Neue", Helvetica, Arial, sans-serif;
    color: var(--text);
    background: var(--bg);
    line-height: 1.7;
    -webkit-font-smoothing: antialiased;
    overflow-x: hidden;
}

a { text-decoration: none; color: inherit; }
ul { list-style: none; }
img { max-width: 100%; display: block; }
button { font-family: inherit; cursor: pointer; border: none; background: none; }

/* ---------- 通用容器 ---------- */
.container {
    width: 100%;
    max-width: var(--container);
    margin: 0 auto;
    padding: 0 24px;
}

.section {
    padding: 100px 0;
    position: relative;
}
.section-alt { background: var(--bg-alt); }

/* ---------- 图标 ---------- */
.icon {
    width: 1em;
    height: 1em;
    display: inline-block;
    vertical-align: -0.15em;
    fill: currentColor;
}
svg.icon { width: 1.1em; height: 1.1em; }

/* ---------- 按钮 ---------- */
.btn {
    display: inline-flex;
    align-items: center;
    gap: 8px;
    padding: 14px 28px;
    border-radius: var(--radius-sm);
    font-size: 15px;
    font-weight: 600;
    transition: all .25s ease;
    cursor: pointer;
    white-space: nowrap;
}
.btn-primary {
    background: linear-gradient(135deg, var(--primary), var(--secondary));
    color: #fff;
    box-shadow: var(--shadow-primary);
}
.btn-primary:hover {
    transform: translateY(-2px);
    box-shadow: 0 16px 36px rgba(79, 124, 255, 0.45);
}
.btn-outline {
    background: transparent;
    color: var(--text);
    border: 2px solid var(--border);
}
.btn-outline:hover {
    border-color: var(--primary);
    color: var(--primary);
}
.btn-block { width: 100%; justify-content: center; }

/* ============================================================
   导航栏
   ============================================================ */
.header {
    position: fixed;
    top: 0; left: 0; right: 0;
    height: var(--header-h);
    background: rgba(255, 255, 255, 0.85);
    backdrop-filter: saturate(180%) blur(14px);
    -webkit-backdrop-filter: saturate(180%) blur(14px);
    border-bottom: 1px solid transparent;
    z-index: 1000;
    transition: all .3s ease;
}
.header.scrolled {
    background: rgba(255, 255, 255, 0.95);
    border-bottom-color: var(--border);
    box-shadow: var(--shadow-sm);
}
.nav-container {
    height: 100%;
    display: flex;
    align-items: center;
    justify-content: space-between;
}

.logo {
    display: flex;
    align-items: center;
    gap: 10px;
    font-weight: 800;
    font-size: 20px;
}
.logo-icon {
    width: 38px; height: 38px;
    display: grid; place-items: center;
    background: linear-gradient(135deg, var(--primary), var(--secondary));
    color: #fff;
    border-radius: 10px;
    font-size: 20px;
    box-shadow: var(--shadow-primary);
}
.logo-text {
    background: linear-gradient(135deg, var(--primary), var(--secondary));
    -webkit-background-clip: text;
    background-clip: text;
    -webkit-text-fill-color: transparent;
}

.nav-menu {
    display: flex;
    gap: 8px;
    align-items: center;
}
.nav-link {
    padding: 8px 16px;
    font-size: 15px;
    font-weight: 500;
    color: var(--text-light);
    border-radius: var(--radius-sm);
    transition: all .2s ease;
    position: relative;
}
.nav-link:hover { color: var(--primary); background: rgba(79,124,255,.08); }
.nav-link.active { color: var(--primary); }
.nav-link.active::after {
    content: '';
    position: absolute;
    bottom: 2px; left: 50%;
    transform: translateX(-50%);
    width: 20px; height: 3px;
    background: linear-gradient(90deg, var(--primary), var(--secondary));
    border-radius: 3px;
}

.menu-toggle {
    display: none;
    flex-direction: column;
    gap: 5px;
    padding: 8px;
}
.menu-toggle span {
    width: 24px; height: 2px;
    background: var(--text);
    border-radius: 2px;
    transition: all .3s ease;
}
.menu-toggle.active span:nth-child(1) { transform: translateY(7px) rotate(45deg); }
.menu-toggle.active span:nth-child(2) { opacity: 0; }
.menu-toggle.active span:nth-child(3) { transform: translateY(-7px) rotate(-45deg); }

/* ============================================================
   Hero 首页
   ============================================================ */
.hero {
    position: relative;
    min-height: 100vh;
    padding: calc(var(--header-h) + 60px) 0 80px;
    display: flex;
    align-items: center;
    overflow: hidden;
}
.hero-bg {
    position: absolute;
    inset: 0;
    z-index: 0;
}
.hero-gradient {
    position: absolute;
    inset: 0;
    background:
        radial-gradient(circle at 20% 30%, rgba(79,124,255,.15), transparent 50%),
        radial-gradient(circle at 80% 70%, rgba(165,94,234,.15), transparent 50%),
        linear-gradient(180deg, #f8faff 0%, #ffffff 100%);
}
.hero-particles {
    position: absolute;
    inset: 0;
    background-image:
        radial-gradient(circle, rgba(79,124,255,.08) 1px, transparent 1px),
        radial-gradient(circle, rgba(165,94,234,.06) 1px, transparent 1px);
    background-size: 40px 40px, 60px 60px;
    background-position: 0 0, 20px 20px;
}

.hero-content {
    position: relative;
    z-index: 1;
    display: grid;
    grid-template-columns: 1.1fr 1fr;
    gap: 60px;
    align-items: center;
}
.hero-tag {
    display: inline-block;
    padding: 7px 16px;
    background: rgba(79,124,255,.1);
    color: var(--primary);
    border-radius: 30px;
    font-size: 13px;
    font-weight: 600;
    margin-bottom: 24px;
}
.hero-title {
    font-size: clamp(2.2rem, 5vw, 3.6rem);
    font-weight: 800;
    line-height: 1.2;
    letter-spacing: -1px;
    margin-bottom: 24px;
}
.highlight {
    background: linear-gradient(135deg, var(--primary), var(--secondary));
    -webkit-background-clip: text;
    background-clip: text;
    -webkit-text-fill-color: transparent;
}
.hero-subtitle {
    font-size: 17px;
    color: var(--text-light);
    margin-bottom: 36px;
    max-width: 540px;
}
.hero-actions {
    display: flex;
    gap: 16px;
    margin-bottom: 56px;
    flex-wrap: wrap;
}

.hero-stats {
    display: flex;
    gap: 48px;
}
.stat-item {
    display: flex;
    flex-direction: column;
}
.stat-num {
    font-size: 36px;
    font-weight: 800;
    color: var(--primary);
    line-height: 1;
    display: inline-block;
}
.stat-suffix {
    font-size: 24px;
    font-weight: 800;
    color: var(--primary);
}
.stat-label {
    font-size: 14px;
    color: var(--text-muted);
    margin-top: 6px;
}

/* Hero 视觉区 */
.hero-visual {
    position: relative;
    min-height: 420px;
}
.code-window {
    background: #1a1f3a;
    border-radius: var(--radius);
    overflow: hidden;
    box-shadow: var(--shadow-lg);
    transform: rotate(-1.5deg);
    transition: transform .4s ease;
}
.code-window:hover { transform: rotate(0); }
.code-header {
    display: flex;
    align-items: center;
    gap: 8px;
    padding: 14px 18px;
    background: rgba(0,0,0,.2);
}
.dot { width: 12px; height: 12px; border-radius: 50%; }
.dot.red { background: #ff5f57; }
.dot.yellow { background: #febc2e; }
.dot.green { background: #28c840; }
.code-title {
    margin-left: 12px;
    color: #8a93b0;
    font-size: 13px;
    font-family: monospace;
}
.code-body {
    padding: 24px;
    font-family: "Fira Code", "Consolas", "Monaco", monospace;
    font-size: 13.5px;
    line-height: 1.8;
    color: #c8d0e8;
    overflow-x: auto;
}
.c-keyword { color: #c792ea; }
.c-string { color: #c3e88d; }
.c-comment { color: #546e7a; font-style: italic; }
.c-func { color: #82aaff; }

.floating-card {
    position: absolute;
    background: #fff;
    padding: 14px 18px;
    border-radius: var(--radius);
    box-shadow: var(--shadow-lg);
    display: flex;
    align-items: center;
    gap: 12px;
    font-size: 14px;
    z-index: 2;
}
.floating-card strong { display: block; font-size: 14px; }
.floating-card span { font-size: 12px; color: var(--text-muted); }
.floating-card .icon { font-size: 24px; color: var(--primary); }
.card-1 {
    top: 8%; left: -6%;
    animation: float 4s ease-in-out infinite;
}
.card-2 {
    bottom: 10%; right: -4%;
    animation: float 4s ease-in-out infinite 1.5s;
}
.card-2 .icon { color: var(--accent); }

@keyframes float {
    0%, 100% { transform: translateY(0); }
    50% { transform: translateY(-12px); }
}

/* ============================================================
   通用 Section 头部
   ============================================================ */
.section-header {
    text-align: center;
    max-width: 720px;
    margin: 0 auto 60px;
}
.section-tag {
    display: inline-block;
    padding: 6px 16px;
    background: rgba(79,124,255,.1);
    color: var(--primary);
    border-radius: 30px;
    font-size: 13px;
    font-weight: 600;
    margin-bottom: 16px;
}
.section-title {
    font-size: clamp(1.8rem, 3.5vw, 2.6rem);
    font-weight: 800;
    letter-spacing: -0.5px;
    margin-bottom: 16px;
}
.section-desc {
    font-size: 16px;
    color: var(--text-light);
}

/* ============================================================
   服务卡片
   ============================================================ */
.services-grid {
    display: grid;
    grid-template-columns: repeat(4, 1fr);
    gap: 28px;
}
.service-card {
    background: #fff;
    border: 1px solid var(--border);
    border-radius: var(--radius-lg);
    padding: 36px 28px;
    transition: all .35s cubic-bezier(.4,0,.2,1);
    position: relative;
    overflow: hidden;
}
.service-card::before {
    content: '';
    position: absolute;
    top: 0; left: 0; right: 0;
    height: 4px;
    background: linear-gradient(90deg, var(--primary), var(--secondary));
    transform: scaleX(0);
    transform-origin: left;
    transition: transform .35s ease;
}
.service-card:hover {
    transform: translateY(-8px);
    box-shadow: var(--shadow-lg);
    border-color: transparent;
}
.service-card:hover::before { transform: scaleX(1); }

.service-icon {
    width: 64px; height: 64px;
    display: grid; place-items: center;
    border-radius: 18px;
    font-size: 30px;
    color: #fff;
    margin-bottom: 24px;
}
.icon-bg-purple { background: linear-gradient(135deg, #a55eea, #7b2ff7); }
.icon-bg-blue { background: linear-gradient(135deg, #4f7cff, #2563eb); }
.icon-bg-green { background: linear-gradient(135deg, #26de81, #08a336); }
.icon-bg-orange { background: linear-gradient(135deg, #ff9f43, #ee5a24); }

.service-card h3 {
    font-size: 20px;
    font-weight: 700;
    margin-bottom: 12px;
}
.service-card > p {
    color: var(--text-light);
    font-size: 14.5px;
    margin-bottom: 20px;
}
.service-features {
    margin-bottom: 24px;
}
.service-features li {
    display: flex;
    align-items: center;
    gap: 8px;
    padding: 5px 0;
    font-size: 14px;
    color: var(--text);
}
.service-features .icon {
    color: var(--accent);
    font-size: 16px;
}
.service-link {
    display: inline-flex;
    align-items: center;
    gap: 6px;
    color: var(--primary);
    font-weight: 600;
    font-size: 14px;
    transition: gap .2s ease;
}
.service-link:hover { gap: 12px; }

/* ============================================================
   Demo 演示区
   ============================================================ */
.demo-tabs {
    display: flex;
    justify-content: center;
    gap: 8px;
    margin-bottom: 40px;
    flex-wrap: wrap;
}
.demo-tab {
    display: inline-flex;
    align-items: center;
    gap: 8px;
    padding: 12px 22px;
    background: #fff;
    border: 2px solid var(--border);
    border-radius: 30px;
    font-size: 14px;
    font-weight: 600;
    color: var(--text-light);
    transition: all .25s ease;
}
.demo-tab .icon { font-size: 18px; }
.demo-tab:hover { border-color: var(--primary); color: var(--primary); }
.demo-tab.active {
    background: linear-gradient(135deg, var(--primary), var(--secondary));
    color: #fff;
    border-color: transparent;
    box-shadow: var(--shadow-primary);
}

.demo-panel {
    display: none;
    grid-template-columns: 1fr 1.2fr;
    gap: 50px;
    align-items: center;
    background: #fff;
    padding: 48px;
    border-radius: var(--radius-lg);
    box-shadow: var(--shadow-md);
    border: 1px solid var(--border);
    animation: fadeIn .5s ease;
}
.demo-panel.active { display: grid; }

@keyframes fadeIn {
    from { opacity: 0; transform: translateY(20px); }
    to { opacity: 1; transform: translateY(0); }
}

.demo-info h3 {
    font-size: 26px;
    margin-bottom: 14px;
}
.demo-info > p {
    color: var(--text-light);
    margin-bottom: 24px;
}
.demo-highlights li {
    padding: 8px 0;
    font-size: 15px;
    color: var(--text);
}

/* ---- Demo Stage ---- */
.demo-stage {
    display: flex;
    justify-content: center;
    align-items: center;
    min-height: 460px;
}

/* AI Chat Demo */
.chat-window {
    width: 100%;
    max-width: 420px;
    background: #fafbff;
    border: 1px solid var(--border);
    border-radius: var(--radius);
    overflow: hidden;
    box-shadow: var(--shadow-md);
    display: flex;
    flex-direction: column;
    height: 460px;
}
.chat-header {
    display: flex;
    align-items: center;
    gap: 12px;
    padding: 16px;
    background: linear-gradient(135deg, var(--primary), var(--secondary));
    color: #fff;
}
.chat-bot-avatar {
    width: 40px; height: 40px;
    background: rgba(255,255,255,.25);
    border-radius: 50%;
    display: grid; place-items: center;
    font-weight: 800;
    font-size: 14px;
}
.chat-header strong { display: block; font-size: 15px; }
.chat-status { font-size: 12px; opacity: .85; }
.chat-body {
    flex: 1;
    padding: 16px;
    overflow-y: auto;
    display: flex;
    flex-direction: column;
    gap: 12px;
}
.chat-msg {
    display: flex;
    max-width: 85%;
}
.chat-msg.bot { align-self: flex-start; }
.chat-msg.user { align-self: flex-end; justify-content: flex-end; }
.msg-bubble {
    padding: 12px 16px;
    border-radius: 16px;
    font-size: 14px;
    line-height: 1.6;
}
.chat-msg.bot .msg-bubble {
    background: #fff;
    border: 1px solid var(--border);
    border-bottom-left-radius: 4px;
}
.chat-msg.user .msg-bubble {
    background: linear-gradient(135deg, var(--primary), var(--secondary));
    color: #fff;
    border-bottom-right-radius: 4px;
}
.msg-typing {
    display: inline-flex;
    gap: 4px;
    padding: 14px 16px;
}
.msg-typing span {
    width: 7px; height: 7px;
    background: var(--text-muted);
    border-radius: 50%;
    animation: blink 1.4s infinite both;
}
.msg-typing span:nth-child(2) { animation-delay: .2s; }
.msg-typing span:nth-child(3) { animation-delay: .4s; }
@keyframes blink {
    0%, 80%, 100% { opacity: .3; transform: scale(.8); }
    40% { opacity: 1; transform: scale(1); }
}

.chat-quick {
    display: flex;
    gap: 6px;
    padding: 8px 12px;
    flex-wrap: wrap;
    border-top: 1px solid var(--border);
}
.quick-btn {
    padding: 6px 12px;
    background: rgba(79,124,255,.08);
    color: var(--primary);
    border-radius: 16px;
    font-size: 12px;
    transition: all .2s;
}
.quick-btn:hover { background: var(--primary); color: #fff; }

.chat-input {
    display: flex;
    gap: 8px;
    padding: 12px;
    border-top: 1px solid var(--border);
    background: #fff;
}
.chat-input input {
    flex: 1;
    border: 1px solid var(--border);
    border-radius: 22px;
    padding: 10px 16px;
    font-size: 14px;
    outline: none;
    transition: border-color .2s;
}
.chat-input input:focus { border-color: var(--primary); }
.chat-input button {
    width: 40px; height: 40px;
    border-radius: 50%;
    background: linear-gradient(135deg, var(--primary), var(--secondary));
    color: #fff;
    font-size: 16px;
    display: grid; place-items: center;
    transition: transform .2s;
}
.chat-input button:hover { transform: scale(1.1); }

/* Java Dashboard Demo */
.dashboard {
    width: 100%;
    background: #1a1f3a;
    border-radius: var(--radius);
    overflow: hidden;
    color: #e8ecf5;
    box-shadow: var(--shadow-lg);
}
.dash-header {
    padding: 14px 18px;
    background: rgba(0,0,0,.25);
    font-size: 13px;
    font-weight: 600;
    color: #82aaff;
    font-family: monospace;
}
.dash-grid {
    display: grid;
    grid-template-columns: repeat(2, 1fr);
    gap: 16px;
    padding: 20px;
}
.dash-card {
    background: rgba(255,255,255,.05);
    padding: 14px;
    border-radius: var(--radius-sm);
}
.dash-label {
    font-size: 12px;
    color: #8a93b0;
    display: block;
    margin-bottom: 8px;
}
.dash-bar {
    height: 6px;
    background: rgba(255,255,255,.1);
    border-radius: 3px;
    overflow: hidden;
    margin-bottom: 8px;
}
.dash-bar-fill {
    height: 100%;
    border-radius: 3px;
    transition: width 1s ease;
}
.dash-value {
    font-size: 15px;
    font-weight: 700;
    color: #fff;
}
.dash-log {
    padding: 16px 20px 20px;
    font-family: monospace;
    font-size: 12px;
    line-height: 1.9;
    max-height: 140px;
    overflow-y: auto;
}
.log-title {
    color: #c792ea;
    font-weight: 600;
    margin-bottom: 6px;
}
.log-time { color: #546e7a; }
.log-level {
    display: inline-block;
    padding: 0 6px;
    border-radius: 3px;
    font-size: 10px;
    font-weight: 700;
    margin: 0 4px;
}
.log-level.info { background: rgba(38,222,129,.2); color: #26de81; }
.log-level.warn { background: rgba(255,159,67,.2); color: #ff9f43; }

/* Mini-app Phone Demo */
.phone-frame {
    width: 260px;
    height: 480px;
    background: #1a1f3a;
    border-radius: 36px;
    padding: 10px;
    box-shadow: var(--shadow-lg), inset 0 0 0 2px rgba(255,255,255,.05);
    position: relative;
}
.phone-notch {
    position: absolute;
    top: 10px; left: 50%;
    transform: translateX(-50%);
    width: 80px; height: 18px;
    background: #1a1f3a;
    border-radius: 0 0 14px 14px;
    z-index: 3;
}
.phone-screen {
    width: 100%; height: 100%;
    background: #f5f5f7;
    border-radius: 28px;
    overflow: hidden;
    display: flex;
    flex-direction: column;
}
.app-header {
    display: flex;
    align-items: center;
    justify-content: space-between;
    padding: 26px 14px 10px;
    background: #fff;
}
.app-title { font-weight: 800; font-size: 16px; color: var(--text); }
.app-search {
    font-size: 12px;
    color: var(--text-muted);
    background: var(--bg-alt);
    padding: 6px 12px;
    border-radius: 20px;
}
.app-banner {
    margin: 10px;
    padding: 12px;
    background: linear-gradient(135deg, #ff9f43, #ee5a24);
    color: #fff;
    border-radius: 10px;
    font-size: 13px;
    font-weight: 600;
    text-align: center;
}
.app-products {
    flex: 1;
    overflow-y: auto;
    padding: 4px 10px;
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 8px;
}
.app-product {
    background: #fff;
    border-radius: 10px;
    overflow: hidden;
    box-shadow: 0 2px 6px rgba(0,0,0,.04);
}
.product-img {
    height: 70px;
    display: grid; place-items: center;
    font-size: 30px;
}
.product-info { padding: 6px 8px; }
.product-name { font-size: 11px; font-weight: 600; color: var(--text); }
.product-price { font-size: 13px; color: #ee5a24; font-weight: 700; margin-top: 2px; }
.product-old { font-size: 10px; color: var(--text-muted); text-decoration: line-through; font-weight: 400; margin-left: 2px;}
.app-tabbar {
    display: flex;
    background: #fff;
    border-top: 1px solid var(--border);
    padding: 6px 0;
}
.app-tabbar .tab {
    flex: 1;
    text-align: center;
    font-size: 10px;
    color: var(--text-muted);
    padding: 4px 0;
}
.app-tabbar .tab.active { color: var(--primary); font-weight: 600; }

/* Website Preview Demo */
.website-preview {
    width: 100%;
    background: #fff;
    border-radius: var(--radius);
    overflow: hidden;
    box-shadow: var(--shadow-lg);
    border: 1px solid var(--border);
}
.browser-bar {
    display: flex;
    align-items: center;
    gap: 6px;
    padding: 10px 14px;
    background: #f1f3f9;
    border-bottom: 1px solid var(--border);
}
.browser-bar .dot { width: 10px; height: 10px; }
.browser-url {
    flex: 1;
    margin-left: 10px;
    background: #fff;
    padding: 5px 12px;
    border-radius: 14px;
    font-size: 11px;
    color: var(--text-muted);
    font-family: monospace;
}
.browser-body { padding: 28px 24px; }
.ws-hero {
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    border-radius: var(--radius);
    padding: 32px 24px;
    color: #fff;
    text-align: center;
    margin-bottom: 20px;
}
.ws-badge {
    display: inline-block;
    background: rgba(255,255,255,.2);
    padding: 4px 12px;
    border-radius: 14px;
    font-size: 11px;
    margin-bottom: 12px;
}
.ws-hero h4 { font-size: 22px; margin-bottom: 8px; }
.ws-hero p { font-size: 13px; opacity: .9; margin-bottom: 18px; }
.ws-btns { display: flex; gap: 8px; justify-content: center; }
.ws-btn {
    padding: 8px 18px;
    border-radius: 18px;
    font-size: 12px;
    font-weight: 600;
}
.ws-btn.primary { background: #fff; color: #764ba2; }
.ws-btn { background: rgba(255,255,255,.2); color: #fff; }
.ws-features {
    display: grid;
    grid-template-columns: repeat(4, 1fr);
    gap: 10px;
}
.ws-feat {
    text-align: center;
    padding: 14px 6px;
    background: var(--bg-alt);
    border-radius: var(--radius-sm);
    font-size: 12px;
    font-weight: 600;
}
.ws-feat span { display: block; margin-top: 6px; }

/* ============================================================
   关于我们
   ============================================================ */
.about-grid {
    display: grid;
    grid-template-columns: 1.2fr 1fr;
    gap: 60px;
    align-items: center;
}
.about-text h3 {
    font-size: 28px;
    margin-bottom: 20px;
}
.about-text p {
    color: var(--text-light);
    margin-bottom: 18px;
    font-size: 16px;
}
.about-text em {
    color: var(--primary);
    font-style: normal;
    font-weight: 600;
}
.about-values {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 20px;
    margin-top: 32px;
}
.value-item {
    text-align: left;
}
.value-icon {
    font-size: 32px;
    margin-bottom: 10px;
}
.value-item h4 {
    font-size: 16px;
    margin-bottom: 6px;
}
.value-item p {
    font-size: 13px;
    color: var(--text-muted);
    margin: 0;
}

.about-card-stack {
    position: relative;
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 20px;
}
.about-card {
    background: linear-gradient(135deg, var(--primary), var(--secondary));
    color: #fff;
    padding: 36px 24px;
    border-radius: var(--radius-lg);
    text-align: center;
    box-shadow: var(--shadow-primary);
    transition: transform .3s ease;
}
.about-card:hover { transform: translateY(-6px) scale(1.02); }
.about-card.ac-2 { background: linear-gradient(135deg, #26de81, #08a336); }
.about-card.ac-3 { background: linear-gradient(135deg, #ff9f43, #ee5a24); }
.about-card.ac-4 { background: linear-gradient(135deg, #a55eea, #7b2ff7); }
.ac-num {
    font-size: 42px;
    font-weight: 800;
    line-height: 1;
    margin-bottom: 8px;
}
.ac-label { font-size: 14px; opacity: .9; }

/* ============================================================
   技术栈
   ============================================================ */
.tech-grid {
    display: grid;
    grid-template-columns: repeat(4, 1fr);
    gap: 20px;
}
.tech-item {
    display: flex;
    align-items: center;
    justify-content: center;
    gap: 10px;
    padding: 22px 16px;
    background: #fff;
    border: 1px solid var(--border);
    border-radius: var(--radius);
    font-weight: 600;
    font-size: 15px;
    transition: all .25s ease;
}
.tech-item:hover {
    transform: translateY(-4px);
    box-shadow: var(--shadow-md);
    border-color: var(--primary);
    color: var(--primary);
}
.tech-emoji { font-size: 24px; }

/* ============================================================
   联系我们
   ============================================================ */
.contact-wrap {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 60px;
    align-items: start;
}
.contact-list {
    margin-top: 32px;
}
.contact-item {
    display: flex;
    align-items: center;
    gap: 16px;
    padding: 18px 0;
    border-bottom: 1px solid var(--border);
    font-size: 15px;
    color: var(--text-light);
}
.contact-item strong { color: var(--text); font-size: 15px; }
.contact-ic {
    width: 48px; height: 48px;
    display: grid; place-items: center;
    background: rgba(79,124,255,.1);
    border-radius: 14px;
    font-size: 22px;
    flex-shrink: 0;
}

.contact-form {
    background: #fff;
    padding: 36px;
    border-radius: var(--radius-lg);
    box-shadow: var(--shadow-md);
    border: 1px solid var(--border);
}
.contact-form h3 {
    font-size: 22px;
    margin-bottom: 24px;
}
.form-group {
    margin-bottom: 18px;
}
.form-group label {
    display: block;
    font-size: 14px;
    font-weight: 600;
    margin-bottom: 8px;
    color: var(--text);
}
.form-group input,
.form-group select,
.form-group textarea {
    width: 100%;
    padding: 12px 16px;
    border: 1.5px solid var(--border);
    border-radius: var(--radius-sm);
    font-size: 14px;
    font-family: inherit;
    color: var(--text);
    outline: none;
    transition: border-color .2s;
    background: #fff;
}
.form-group input:focus,
.form-group select:focus,
.form-group textarea:focus {
    border-color: var(--primary);
}
.form-tip {
    margin-top: 12px;
    font-size: 13px;
    text-align: center;
    color: var(--accent);
    min-height: 18px;
}

/* ============================================================
   页脚
   ============================================================ */
.footer {
    background: var(--bg-dark);
    color: rgba(255,255,255,.7);
    padding-top: 60px;
}
.footer-container {
    display: grid;
    grid-template-columns: 1.5fr 2fr;
    gap: 60px;
    padding-bottom: 40px;
}
.footer-brand .logo { margin-bottom: 16px; }
.footer-brand .logo-text { color: #fff; -webkit-text-fill-color: #fff; }
.footer-brand p { font-size: 14px; max-width: 320px; }

.footer-links {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 30px;
}
.footer-col h4 {
    color: #fff;
    font-size: 15px;
    margin-bottom: 16px;
}
.footer-col a {
    display: block;
    padding: 6px 0;
    font-size: 14px;
    color: rgba(255,255,255,.65);
    transition: color .2s;
}
.footer-col a:hover { color: var(--primary); }

.footer-bottom {
    border-top: 1px solid rgba(255,255,255,.1);
    padding: 20px 0;
    text-align: center;
}
.footer-bottom p {
    font-size: 13px;
    color: rgba(255,255,255,.5);
}

/* ============================================================
   返回顶部
   ============================================================ */
.back-top {
    position: fixed;
    bottom: 30px; right: 30px;
    width: 48px; height: 48px;
    border-radius: 50%;
    background: linear-gradient(135deg, var(--primary), var(--secondary));
    color: #fff;
    font-size: 22px;
    box-shadow: var(--shadow-primary);
    opacity: 0;
    visibility: hidden;
    transform: translateY(20px);
    transition: all .3s ease;
    z-index: 999;
}
.back-top.show {
    opacity: 1;
    visibility: visible;
    transform: translateY(0);
}
.back-top:hover { transform: translateY(-4px); }

/* ============================================================
   滚动动画
   ============================================================ */
.reveal {
    opacity: 0;
    transform: translateY(40px);
    transition: opacity .8s ease, transform .8s ease;
}
.reveal.visible {
    opacity: 1;
    transform: translateY(0);
}