/* 
 * 创域科博建站 - 全局样式
 * 影视简约风 | 浅灰 + 黑色 + 暗红
 */

/* ========== CSS Reset & Base ========== */
* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

html {
    scroll-behavior: smooth;
    font-size: 16px;
}

body {
    font-family: 'Helvetica Neue', Helvetica, Arial, 'Microsoft YaHei', sans-serif;
    background-color: #f5f5f5;
    color: #1a1a1a;
    line-height: 1.6;
    overflow-x: hidden;
}

a {
    text-decoration: none;
    color: inherit;
    transition: all 0.3s ease;
}

ul, ol {
    list-style: none;
}

img {
    max-width: 100%;
    height: auto;
    display: block;
}

.container {
    max-width: 1400px;
    margin: 0 auto;
    padding: 0 20px;
}

.section {
    padding: 80px 0;
}

/* ========== Header & Navigation ========== */
.header {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    z-index: 1000;
    background: transparent;
    transition: all 0.4s ease;
    padding: 20px 0;
}

.header.scrolled {
    background: rgba(10, 10, 10, 0.95);
    backdrop-filter: blur(10px);
    padding: 15px 0;
    box-shadow: 0 2px 20px rgba(0, 0, 0, 0.3);
}

.nav-wrapper {
    display: flex;
    justify-content: space-between;
    align-items: center;
}

.logo {
    font-size: 28px;
    font-weight: 700;
    color: #fff;
    letter-spacing: 2px;
}

.logo span {
    color: #c41e3a;
}

.nav-menu {
    display: flex;
    gap: 40px;
}

.nav-link {
    color: #fff;
    font-size: 15px;
    font-weight: 500;
    letter-spacing: 1px;
    position: relative;
    padding: 5px 0;
}

.nav-link::after {
    content: '';
    position: absolute;
    bottom: 0;
    left: 0;
    width: 0;
    height: 2px;
    background: #c41e3a;
    transition: width 0.3s ease;
}

.nav-link:hover::after,
.nav-link.active::after {
    width: 100%;
}

.nav-link:hover {
    color: #c41e3a;
}

.hamburger {
    display: none;
    flex-direction: column;
    cursor: pointer;
    gap: 5px;
}

.hamburger span {
    width: 25px;
    height: 2px;
    background: #fff;
    transition: all 0.3s ease;
}

.hamburger.active span:nth-child(1) {
    transform: rotate(45deg) translate(5px, 5px);
}

.hamburger.active span:nth-child(2) {
    opacity: 0;
}

.hamburger.active span:nth-child(3) {
    transform: rotate(-45deg) translate(7px, -6px);
}

/* ========== Footer ========== */
.footer {
    background: #0a0a0a;
    color: #ccc;
    padding: 60px 0 30px;
}

.footer-content {
    display: grid;
    grid-template-columns: repeat(4, 1fr);
    gap: 40px;
    margin-bottom: 40px;
}

.footer-section h4 {
    color: #fff;
    font-size: 18px;
    margin-bottom: 20px;
    position: relative;
    padding-bottom: 10px;
}

.footer-section h4::after {
    content: '';
    position: absolute;
    bottom: 0;
    left: 0;
    width: 40px;
    height: 2px;
    background: #c41e3a;
}

.footer-section p,
.footer-section li {
    font-size: 14px;
    line-height: 2;
    color: #999;
}

.footer-section a:hover {
    color: #c41e3a;
}

.footer-links li {
    margin-bottom: 10px;
}

.footer-bottom {
    border-top: 1px solid #222;
    padding-top: 30px;
    text-align: center;
    font-size: 14px;
    color: #666;
}

/* ========== Buttons ========== */
.btn {
    display: inline-block;
    padding: 14px 35px;
    font-size: 15px;
    font-weight: 600;
    letter-spacing: 1px;
    border: none;
    cursor: pointer;
    transition: all 0.3s ease;
    text-transform: uppercase;
}

.btn-primary {
    background: #c41e3a;
    color: #fff;
}

.btn-primary:hover {
    background: #a01830;
    transform: translateY(-2px);
    box-shadow: 0 5px 20px rgba(196, 30, 58, 0.4);
}

.btn-outline {
    background: transparent;
    color: #fff;
    border: 2px solid #fff;
}

.btn-outline:hover {
    background: #fff;
    color: #0a0a0a;
}

/* ========== Animations ========== */
.fade-in {
    opacity: 0;
    transform: translateY(30px);
    transition: all 0.6s ease;
}

.fade-in.visible {
    opacity: 1;
    transform: translateY(0);
}

/* ========== Responsive ========== */
@media (max-width: 992px) {
    .nav-menu {
        position: fixed;
        top: 0;
        right: -100%;
        width: 300px;
        height: 100vh;
        background: #0a0a0a;
        flex-direction: column;
        padding: 80px 30px;
        gap: 25px;
        transition: right 0.4s ease;
    }

    .nav-menu.active {
        right: 0;
    }

    .hamburger {
        display: flex;
    }

    .footer-content {
        grid-template-columns: repeat(2, 1fr);
    }
}

@media (max-width: 576px) {
    .footer-content {
        grid-template-columns: 1fr;
    }

    .section {
        padding: 50px 0;
    }
}