/* ============================================================
   飞流科技官网 · 设计系统 v2.0（CIS 标准版 · 浅色/深色双轨）
   依据：software/cis/fleetness-cis.md ｜ 方案 A · v8「激流破浪 · 聚水成潭」

   浅色背景主色（沉稳聚势体系）：
     极速深蓝 --deep  #0C4A6E  浅底海浪底座 · 水翼落点
     电光蓝   --bolt  #0284C7  浅底水翼中段 · 英文标准字
     破浪青   --teal  #2DD4BF  水翼起笔高光 · 内旋浪冠
     浪冠亮青         #22D3EE  外旋浪冠高光
   品牌渐变：135°（自右上至左下）破浪青 → 电光蓝 → 极速深蓝

   深色背景专属高亮色（极光流光体系，深底专用，CIS §2.4.2）：
     极光冰青   --aurora-cyan  #A5F3FC  深底顶翼 · 外旋浪冠峰顶（对比度 13.4:1）
     荧光破浪青 --aurora-teal  #5EEAD4  深底主水翼上段 · 内旋浪冠（11.8:1）
     晴空电光蓝 --sky-bolt     #38BDF8  深底主水翼中段 · fleetness 标准字（9.8:1）
     深海亮蓝   --deep-glow    #0EA5E9  深底海浪底座主色（7.6:1）
     深空曜黑   --space        #070B14  深底舞台基准

   中性色：
     墨夜黑 --ink   #0F172A   浅色底标题字
     岩灰   --rock  #64748B   定位语 · 说明文字
     雾白   --mist  #F8FAFC   深色底反白
     暗夜深空 --night #0B1020 深色舞台背景

   子品牌色彩矩阵（一核多翼 · 换色不换形 · 浅底版）：
     易面试 · 专业深蓝  #1E3A8A / #2563EB / #60A5FA  点缀 #38BDF8
     易陪练 · 成长青绿  #065F46 / #0D9488 / #34D399  点缀 #6EE7B7

   字体：Inter + Noto Sans SC（兜底苹方/微软雅黑）；技术文本 JetBrains Mono
   动效：水翼破空推进 bladeGlide 2.8s/3.2s 错峰 ｜ 碧波涌动与卷浪呼吸 waveSwell 2.6s/3.4s（底盘始终稳固）
   ============================================================ */

:root {
    /* 品牌主色（浅色背景体系） */
    --deep: #0C4A6E;
    --bolt: #0284C7;
    --teal: #2DD4BF;
    /* 深色背景专属高亮色（极光流光体系，CIS §2.4.2 深底专用） */
    --aurora-cyan: #A5F3FC;
    --aurora-teal: #5EEAD4;
    --sky-bolt: #38BDF8;
    --deep-glow: #0EA5E9;
    --space: #070B14;
    /* 中性色 */
    --ink: #0F172A;
    --rock: #64748B;
    --mist: #F8FAFC;
    --night: #0B1020;
    --card: #FFFFFF;
    --line: #E2E8F0;
    --text: #0F172A;
    --text2: #64748B;
    --text3: #94A3B8;
    /* 子品牌 */
    --iv-deep: #1E3A8A;
    --iv-mid: #2563EB;
    --iv-light: #60A5FA;
    --iv-accent: #38BDF8;
    --coach-deep: #065F46;
    --coach-mid: #0D9488;
    --coach-light: #34D399;
    --coach-accent: #6EE7B7;
    /* 品牌渐变（135° 与图形动势同向） */
    --brand-grad: linear-gradient(135deg, var(--teal) 0%, var(--bolt) 50%, var(--deep) 100%);
    --radius: 18px;
    --shadow: 0 18px 50px rgba(12, 74, 110, .12);
}

* { margin: 0; padding: 0; box-sizing: border-box; }

html { scroll-behavior: smooth; }

body {
    font-family: 'Inter', 'Noto Sans SC', -apple-system, BlinkMacSystemFont, 'PingFang SC', 'Microsoft YaHei', 'Segoe UI', sans-serif;
    color: var(--text);
    background: var(--mist);
    line-height: 1.7;
    overflow-x: hidden;
}

.mono {
    font-family: 'JetBrains Mono', ui-monospace, 'SF Mono', SFMono-Regular, Menlo, Consolas, monospace;
    letter-spacing: .12em;
}

.container {
    width: 100%;
    max-width: 1160px;
    margin: 0 auto;
    padding: 0 24px;
}

h1, h2, h3 { line-height: 1.25; font-weight: 900; }

h2 {
    font-size: clamp(1.7rem, 3.4vw, 2.4rem);
    letter-spacing: -.01em;
    margin-bottom: 14px;
}

section { padding: 96px 0; }

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

.eyebrow {
    font-family: 'JetBrains Mono', ui-monospace, 'SF Mono', Menlo, Consolas, monospace;
    font-size: .78rem;
    letter-spacing: .28em;
    color: var(--aurora-teal); /* 深底 eyebrow 用荧光破浪青（11.8:1） */
    margin-bottom: 18px;
}

.eyebrow.dark { color: var(--bolt); }

.section-subtitle {
    color: var(--text2);
    font-size: 1.06rem;
    max-width: 640px;
    margin-bottom: 56px;
}

.btn {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    gap: 8px;
    padding: 12px 26px;
    border-radius: 999px;
    font-weight: 600;
    font-size: .95rem;
    transition: transform .25s ease, box-shadow .25s ease, background .25s ease;
    cursor: pointer;
}

::focus-visible {
    outline: 2px solid var(--teal);
    outline-offset: 3px;
    border-radius: 6px;
}

/* 辅助图形 · 45° 对角动势线底纹（8% 透明度） */
.diag-stripes {
    background-image: repeating-linear-gradient(-45deg, rgba(2, 132, 199, .06) 0 14px, transparent 14px 28px);
}

/* ---------- 顶部导航 ---------- */
header {
    position: fixed;
    top: 0; left: 0; right: 0;
    z-index: 1000;
    background: rgba(11, 16, 32, .78);
    backdrop-filter: blur(14px);
    -webkit-backdrop-filter: blur(14px);
    border-bottom: 1px solid rgba(255, 255, 255, .07);
}

.header-container {
    display: flex;
    align-items: center;
    justify-content: space-between;
    padding: 14px 24px;
}

/* 横版标准组合：图形居左 + 中文 900 + fleetness 小写 */
.logo { display: flex; align-items: center; gap: 10px; }

.logo-img { height: 38px; width: 38px; display: block; }

.logo-text {
    font-size: 1.22rem;
    font-weight: 900;
    color: var(--mist);
    letter-spacing: .02em;
    line-height: 1.15;
}

.logo-en {
    display: block;
    font-family: 'Inter', sans-serif;
    font-size: .68rem;
    font-weight: 700;
    letter-spacing: .12em;
    color: var(--sky-bolt); /* 深底 fleetness 标准字 #38BDF8（替代旧 #93C5FD，对比度 9.8:1） */
    text-transform: lowercase;
}

nav ul { display: flex; list-style: none; gap: 4px; }

nav ul li a {
    color: rgba(248, 250, 252, .78);
    font-size: .92rem;
    font-weight: 500;
    padding: 8px 14px;
    border-radius: 999px;
    transition: color .2s ease, background .2s ease;
}

nav ul li a:hover, nav ul li a.active {
    color: #fff;
    background: rgba(255, 255, 255, .10);
}

.primary-btn {
    background: var(--brand-grad);
    color: #fff;
    font-weight: 700;
}

.primary-btn:hover { transform: translateY(-2px); box-shadow: 0 10px 26px rgba(2, 132, 199, .38); color: #fff; }

/* ---------- Hero ---------- */
.hero {
    position: relative;
    min-height: 92vh;
    display: flex;
    align-items: center;
    background: radial-gradient(1200px 620px at 72% -10%, #123A5C 0%, var(--space) 58%);
    color: var(--mist);
    padding: 140px 0 100px;
    overflow: hidden;
}

#flowfield {
    position: absolute;
    inset: 0;
    width: 100%;
    height: 100%;
    display: block;
}

.hero-inner { position: relative; z-index: 2; }

.hero h1 {
    font-size: clamp(2.3rem, 5.6vw, 4rem);
    letter-spacing: -.02em;
    margin-bottom: 22px;
    background: linear-gradient(135deg, #FFFFFF 20%, var(--aurora-cyan) 58%, var(--aurora-teal) 100%);
    -webkit-background-clip: text;
    background-clip: text;
    -webkit-text-fill-color: transparent;
}

.hero .slogan {
    display: inline-block;
    font-size: .92rem;
    font-weight: 700;
    letter-spacing: .14em;
    color: var(--aurora-teal);
    border: 1px solid rgba(94, 234, 212, .45);
    background: rgba(94, 234, 212, .10);
    border-radius: 999px;
    padding: 6px 16px;
    margin-bottom: 20px;
    backdrop-filter: blur(6px);
}

.hero .subtitle {
    font-size: clamp(1rem, 1.6vw, 1.18rem);
    color: rgba(226, 234, 248, .82);
    margin-bottom: 38px;
}

.hero-tags { display: flex; flex-wrap: wrap; gap: 12px; }

.tag {
    font-size: .86rem;
    font-weight: 600;
    padding: 8px 18px;
    border-radius: 999px;
    border: 1px solid transparent;
    backdrop-filter: blur(6px);
}

/* 三条业务线：全部映射到品牌激流三色的不同深浅，保持同族 */
.tag-teal { color: var(--aurora-teal); border-color: rgba(94, 234, 212, .4);  background: rgba(94, 234, 212, .10); }
.tag-bolt { color: #BAE6FD; border-color: rgba(56, 189, 248, .5);   background: rgba(56, 189, 248, .14); }
.tag-deep { color: #C4D7EA; border-color: rgba(96, 165, 250, .35); background: rgba(12, 74, 110, .35); }

.hero-scroll {
    position: absolute;
    left: 50%;
    bottom: 28px;
    transform: translateX(-50%);
    width: 24px; height: 40px;
    border: 2px solid rgba(255, 255, 255, .35);
    border-radius: 14px;
    z-index: 2;
}

.hero-scroll span {
    position: absolute;
    left: 50%; top: 8px;
    width: 4px; height: 8px;
    margin-left: -2px;
    border-radius: 2px;
    background: var(--aurora-teal);
    animation: scrollHint 1.8s ease-in-out infinite;
}

@keyframes scrollHint {
    0% { transform: translateY(0); opacity: 1; }
    70% { transform: translateY(14px); opacity: 0; }
    100% { transform: translateY(0); opacity: 0; }
}

/* ---------- 三大业务 ---------- */
.business { background: var(--mist); }

.biz-list {
    display: flex;
    flex-direction: column;
    border-top: 1px solid var(--line);
}

.biz-row {
    display: grid;
    grid-template-columns: 80px 1fr 48px;
    align-items: center;
    gap: 24px;
    padding: 34px 8px;
    border-bottom: 1px solid var(--line);
    transition: background .25s ease, padding .25s ease;
}

.biz-row:hover { background: #fff; padding-left: 20px; }

.biz-index { font-size: .95rem; color: var(--text3); }

.biz-name {
    display: flex;
    align-items: center;
    gap: 12px;
    font-size: 1.3rem;
    font-weight: 900;
    margin-bottom: 6px;
}

.dot { width: 10px; height: 10px; border-radius: 50%; display: inline-block; }
.dot-teal { background: var(--teal); box-shadow: 0 0 14px rgba(45, 212, 191, .8); }
.dot-bolt { background: var(--bolt); box-shadow: 0 0 14px rgba(2, 132, 199, .8); }
.dot-deep { background: var(--deep); box-shadow: 0 0 14px rgba(12, 74, 110, .8); }

.biz-desc { color: var(--text2); font-size: .98rem; max-width: 760px; }

.biz-arrow {
    font-size: 1.4rem;
    color: var(--text3);
    transition: transform .25s ease, color .25s ease;
}

.biz-row:hover .biz-arrow { transform: translateX(6px); color: var(--bolt); }

/* ---------- 产品（子品牌色彩矩阵） ---------- */
.apps { background: #fff; }

.product-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(340px, 1fr));
    gap: 28px;
}

.product-card {
    position: relative;
    border-radius: 24px;
    padding: 40px 36px;
    color: #fff;
    overflow: hidden;
    box-shadow: var(--shadow);
    transition: transform .3s ease, box-shadow .3s ease;
}

.product-card:hover { transform: translateY(-6px); box-shadow: 0 28px 64px rgba(12, 74, 110, .22); }

/* 易面试 · 专业深蓝 ｜ 易陪练 · 成长青绿（均取 135° 品牌渐变方向） */
.card-interview { background: linear-gradient(150deg, var(--iv-deep) 0%, var(--iv-mid) 58%, var(--iv-light) 100%); }
.card-coach     { background: linear-gradient(150deg, var(--coach-deep) 0%, var(--coach-mid) 58%, #10B981 100%); }

/* 卡片内 45° 水翼纹样（辅助图形，低透明度） */
.card-interview::after, .card-coach::after {
    content: '';
    position: absolute;
    inset: 0;
    background-image: repeating-linear-gradient(-45deg, rgba(255, 255, 255, .05) 0 12px, transparent 12px 30px);
    pointer-events: none;
}

.product-card > * { position: relative; z-index: 1; }

.card-glow {
    position: absolute;
    width: 340px; height: 340px;
    right: -120px; top: -120px;
    border-radius: 50%;
    background: radial-gradient(circle, rgba(255, 255, 255, .22) 0%, transparent 65%);
    pointer-events: none;
}

.product-head { display: flex; align-items: center; gap: 16px; margin-bottom: 20px; }

.product-logo {
    width: 48px;
    height: 48px;
    object-fit: contain;
    background: #fff;
    border-radius: 12px;
}

.product-card h3 { font-size: 1.5rem; }

.badge-soon {
    font-size: .68rem;
    font-weight: 600;
    vertical-align: middle;
    padding: 3px 10px;
    border-radius: 999px;
    background: rgba(251, 146, 60, .95);
    color: #fff;
    margin-left: 4px;
    letter-spacing: .05em;
}

.product-slogan { font-size: .9rem; color: rgba(255, 255, 255, .82); }

.product-desc { color: rgba(255, 255, 255, .92); margin-bottom: 18px; font-size: .98rem; }

.product-feats {
    list-style: none;
    margin-bottom: 24px;
    display: flex;
    flex-direction: column;
    gap: 8px;
}

.product-feats li {
    font-size: .92rem;
    color: rgba(255, 255, 255, .9);
    padding-left: 22px;
    position: relative;
}

.product-feats li::before {
    content: '';
    position: absolute;
    left: 0; top: 8px;
    width: 12px; height: 6px;
    border-left: 2px solid rgba(255, 255, 255, .85);
    border-bottom: 2px solid rgba(255, 255, 255, .85);
    transform: rotate(-45deg);
}

.product-note {
    font-size: .88rem;
    color: rgba(255, 255, 255, .85);
    background: rgba(255, 255, 255, .12);
    border: 1px solid rgba(255, 255, 255, .18);
    border-radius: 12px;
    padding: 12px 16px;
    margin-bottom: 8px;
}

.app-links { display: flex; flex-wrap: wrap; gap: 12px; margin: 18px 0 18px; }

.app-btn {
    min-width: 150px;
    height: 46px;
    border-radius: 999px;
    font-size: .92rem;
}

.app-icon { width: 20px; height: 20px; object-fit: contain; }

.card-interview .ios-btn { background: #fff; color: var(--iv-mid); }
.card-interview .ios-btn:hover { transform: translateY(-2px); box-shadow: 0 10px 24px rgba(0, 0, 0, .22); color: var(--iv-mid); }

.card-interview .android-btn { background: transparent; color: #fff; border: 1.5px solid rgba(255, 255, 255, .75); }
.card-interview .android-btn:hover { background: rgba(255, 255, 255, .14); color: #fff; }

.card-coach .ios-btn { background: #fff; color: var(--coach-mid); }
.card-coach .ios-btn:hover { transform: translateY(-2px); box-shadow: 0 10px 24px rgba(0, 0, 0, .22); color: var(--coach-mid); }

.card-coach .android-btn { background: transparent; color: #fff; border: 1.5px solid rgba(255, 255, 255, .75); }
.card-coach .android-btn:hover { background: rgba(255, 255, 255, .14); color: #fff; }

.app-btn-soon {
    min-width: 150px;
    height: 46px;
    font-size: .92rem;
    cursor: default;
    opacity: .85;
}
.app-btn-soon:hover { background: transparent; color: #fff; transform: none; box-shadow: none; }

.product-more {
    display: inline-block;
    font-size: .92rem;
    font-weight: 600;
    color: #fff;
    border-bottom: 1px solid rgba(255, 255, 255, .5);
    padding-bottom: 2px;
    transition: border-color .2s ease;
}

.product-more:hover { border-color: #fff; }

/* ---------- FDE（电光蓝强调） ---------- */
.fde { background: var(--mist); }

.fde-steps {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(230px, 1fr));
    gap: 22px;
}

.fde-step {
    background: var(--card);
    border: 1px solid var(--line);
    border-radius: var(--radius);
    padding: 30px 26px;
    transition: transform .25s ease, box-shadow .25s ease, border-color .25s ease;
}

.fde-step:hover {
    transform: translateY(-6px);
    box-shadow: var(--shadow);
    border-color: rgba(2, 132, 199, .4);
}

.step-no {
    display: inline-block;
    font-size: .8rem;
    color: var(--bolt);
    background: rgba(2, 132, 199, .10);
    border: 1px solid rgba(2, 132, 199, .28);
    border-radius: 8px;
    padding: 4px 10px;
    margin-bottom: 16px;
}

.fde-step h3 { font-size: 1.15rem; margin-bottom: 10px; }
.fde-step p { color: var(--text2); font-size: .93rem; }

/* ---------- 咨询（破浪青强调） ---------- */
.consulting { background: #fff; }

.consult-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(240px, 1fr));
    gap: 22px;
}

.consult-card {
    border-radius: var(--radius);
    padding: 30px 26px;
    background: linear-gradient(160deg, #F0FDFB 0%, #FFFFFF 70%);
    border: 1px solid rgba(45, 212, 191, .25);
    transition: transform .25s ease, box-shadow .25s ease;
}

.consult-card:hover { transform: translateY(-6px); box-shadow: var(--shadow); }

.consult-card h3 { font-size: 1.12rem; color: var(--deep); margin-bottom: 10px; }
.consult-card p { color: var(--text2); font-size: .93rem; }

/* ---------- 联系 ---------- */
.contact { background: var(--mist); }

.contact-info {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(240px, 1fr));
    gap: 22px;
}

.contact-item {
    background: var(--card);
    border: 1px solid var(--line);
    border-radius: var(--radius);
    padding: 30px 26px;
    transition: transform .25s ease, box-shadow .25s ease;
}

.contact-item:hover { transform: translateY(-6px); box-shadow: var(--shadow); }

.contact-label {
    display: inline-block;
    font-size: .74rem;
    color: var(--text3);
    margin-bottom: 14px;
}

.contact-item h3 { font-size: 1.1rem; margin-bottom: 6px; }
.contact-item p { color: var(--text2); font-size: .95rem; }

/* ---------- 页脚（暗夜深空反白） ---------- */
footer {
    background: var(--night);
    color: rgba(248, 250, 252, .8);
    padding: 48px 0 24px;
}

.footer-content {
    display: flex;
    justify-content: space-between;
    align-items: center;
    flex-wrap: wrap;
    gap: 20px;
    margin-bottom: 28px;
}

.footer-logo { display: flex; align-items: center; gap: 10px; }
.footer-logo .logo-img { height: 30px; width: 30px; }
.footer-logo .logo-text { font-size: 1.05rem; }

.footer-links { display: flex; gap: 24px; }

.footer-links a { color: rgba(248, 250, 252, .72); font-size: .92rem; transition: color .2s ease; }
.footer-links a:hover { color: #fff; }

.copyright {
    text-align: center;
    color: rgba(248, 250, 252, .45);
    font-size: .85rem;
    padding-top: 20px;
    border-top: 1px solid rgba(255, 255, 255, .08);
}

.copyright a { color: rgba(248, 250, 252, .45); }
.copyright a:hover { color: #fff; }

/* ---------- 入场动画 ---------- */
.reveal {
    opacity: 0;
    transform: translateY(24px);
    transition: opacity .6s ease, transform .6s ease;
}

.reveal.in { opacity: 1; transform: translateY(0); }

/* ---------- 响应式 ---------- */
@media (max-width: 860px) {
    nav { display: none; }
    section { padding: 68px 0; }
    .biz-row { grid-template-columns: 1fr; gap: 10px; padding: 26px 4px; }
    .biz-arrow { display: none; }
    .br-pc { display: none; }
    .hero { min-height: auto; padding: 130px 0 90px; }
}

@media (prefers-reduced-motion: reduce) {
    html { scroll-behavior: auto; }
    .hero-scroll span { animation: none; }
    .reveal { opacity: 1; transform: none; transition: none; }
}