/* ================= 字体 ================= */

@font-face {
    font-family: 'Orbitron';
    src: url('/static/fonts/Orbitron-Regular.ttf') format('truetype');
    font-weight: 400;
}

@font-face {
    font-family: 'Orbitron';
    src: url('/static/fonts/Orbitron-Bold.ttf') format('truetype');
    font-weight: 700;
}


/* ================= 全局 ================= */

* {
    box-sizing: border-box;
}

html {
    scroll-behavior: smooth;
    overflow-x: hidden;
}

body {
    margin: 0;
    padding: 0;

    font-family:
    'Microsoft YaHei',
    Arial,
    sans-serif;

    color: white;
    background: white;

    overflow-x: hidden;
}

.orbitron-font {
    font-family: 'Orbitron', sans-serif;
}


/* ========= NAV ========== */

nav {
    position: fixed;
    top: 0;
    left: 0;

    width: 100%;
    min-height: 60px;

    background: linear-gradient(
        to bottom,
        rgba(15,20,30,0.85),
        rgba(15,20,30,0.55)
    );

    border-bottom: 1px solid rgba(255,255,255,0.08);

    box-shadow: 0 4px 20px rgba(0,0,0,0.4);

    display: flex;
    justify-content: space-between;
    align-items: center;

    padding: 0 30px;

    z-index: 1000;
}

nav a {
    margin: 0 15px;
    text-decoration: none;
    color: white;
    transition: .3s;
}

nav a:hover {
    text-shadow:
    0 0 10px orange,
    0 0 20px red;
}

.logo {
    display: flex;
    align-items: center;

    font-size: min(5vw,1.2em);
    letter-spacing: 1px;

    background: linear-gradient(
        90deg,
        #ef5350,
        #cddc39
    );

    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;

    font-weight: bold;
}

.logo span {
    margin-left: 8px;
}

.nav-right {
    display: flex;
    gap: 20px;
}

.nav-right .content {
    display: flex;
    align-items: center;
}

.mobile-user{
    display:flex;
    flex-direction:row;
    align-items:center;
    gap:10px;
}

.mobile-user form{
    display:inline-flex;
    margin:0;
}

/* ================= HERO ================= */

.hero {
    min-height: 100vh;

    display: flex;
    justify-content: center;
    align-items: center;

    padding: 100px 20px 40px;

    text-align: center;

    background: linear-gradient(
        -45deg,
        #6a1b9a,
        #d32f2f,
        #0288d1,
        #f57c00
    );

    background-size: 400% 400%;

    animation: gradient 15s ease infinite;
}

.hero h1 {
    font-size: min(10vw, 4em);

    margin: 0;
    margin-top: 50px;
    line-height: 1.2;

    text-shadow:
    0 0 10px #ff9800,
    0 0 20px #ff5722;
}

.hero h2 {
    font-size: min(8vw, 3em);

    margin-top: 50px;
    line-height: 1.5;
}

.hero p {

    margin-top: 50px;
    line-height: 1.5;
}



.big-data {
    font-size: min(14vw,64px);

    font-weight: bold;

    margin-top: 20px;
}


/* ================= PAGE ================= */

.page {
    display: none;
    width: 100%;
    padding-top: 80px;
}

.page.active {
    display: block;
}


/* ================= SECTIONS ================= */

.concept {
    background: linear-gradient(
        135deg,
        #2c387e,
        #6a1b9a
    );

    padding: 100px 40px;
    text-align: center;
}

.concept h2 {
    margin-bottom: 20px;

    font-size: min(8vw,2.5em);

    margin-top: 50px;
}

.concept-text {
    max-width: 800px;

    margin: auto;

    line-height: 2;

    font-size: min(4vw,1.2rem);
}


.projects {
    background: linear-gradient(
        135deg,
        #fafafa,
        #A9BFC2
    );

    padding: 80px 40px;

    text-align: center;
}

.projects h2 {
    color: #56403d;
    margin-top: 50px;
}

.projects-grid {
    display: grid;

    grid-template-columns: repeat(auto-fit, minmax(280px,1fr));

    gap: 40px;
}

.tile {
    background: white;

    width: 100%;

    padding: 20px;

    border-radius: 12px;

    color: #56403d;

    transition: transform .3s, box-shadow .3s;

    box-shadow: 0 4px 20px rgba(0,0,0,.1);
}

.tile p {
    color: #139666;
    font-weight: bold;
}

.tile:hover {
    transform: translateY(-5px);

    box-shadow: 0 0 20px orange, 0 0 30px red;
}


.research {
    background: linear-gradient(
        135deg,
        #fffde7,
        #fff8e1
    );

    padding: 80px 40px;

    text-align: center;
}

.research h2,
.research p {
    color: #8a8b99;
    margin-top: 50px;
}


/* ================= 子页面修复 ================= */

#factor,
#model,
#research {
    width: 100%;
    overflow-x: hidden;
}


/* ================= 动画 ================= */

@keyframes gradient {
    0% {
        background-position: 0% 50%;
    }

    50% {
        background-position: 100% 50%;
    }

    100% {
        background-position: 0% 50%;
    }
}


/* ================= 手机适配 ================= */
@media(max-width:768px){

    nav{
        padding:10px 15px;

        display:flex;
        flex-direction:column;
        align-items:center;

        gap:8px;
    }

    /* 第一行 */
    .logo{
        order:1;
    }

    /* 第二行 */
    .nav-right{
        order:2;

        width:100%;
        display:flex;
        justify-content:center;
    }

    .nav-right .content{
        display:flex;
        flex-wrap:wrap;
        justify-content:center;
    }

    nav a{
        margin:5px;
        font-size:14px;
    }

    /* 第三行 */
    .mobile-user{
        order:3;

        display:flex;
        align-items:center;
        justify-content:center;

        gap:12px;
        margin-top:5px;
    }

    .mobile-user form{
        margin:0;
    }

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

.error{
    color:#f87171;
    text-align:center;
    margin-bottom:10px;
}

.success{
    color:#4ade80;
    text-align:center;
    margin-bottom:20px;
    font-weight:bold;
}