/* ========================================
   Nikkitsfun.com - 全局样式
   哑光黑 + 浅灰 + 纯白 简约风格
   ======================================== */

/* CSS Reset & 基础设置 */
* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

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

body {
    font-family: 'PingFang SC', 'Microsoft YaHei', 'Helvetica Neue', Arial, 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;
}

/* 滚动条美化 */
::-webkit-scrollbar {
    width: 8px;
    height: 8px;
}

::-webkit-scrollbar-track {
    background: #e0e0e0;
}

::-webkit-scrollbar-thumb {
    background: #333;
    border-radius: 4px;
}

::-webkit-scrollbar-thumb:hover {
    background: #555;
}

/* ========================================
   顶部导航栏
   ======================================== */
.header {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    z-index: 1000;
    background: rgba(26, 26, 26, 0.95);
    backdrop-filter: blur(10px);
    transition: all 0.3s ease;
    padding: 15px 0;
}

.header.scrolled {
    background: rgba(26, 26, 26, 0.98);
    box-shadow: 0 2px 20px rgba(0, 0, 0, 0.3);
}

.header-container {
    max-width: 1400px;
    margin: 0 auto;
    padding: 0 40px;
    display: flex;
    justify-content: space-between;
    align-items: center;
}

.logo {
    font-size: 28px;
    font-weight: 700;
    color: #ffffff;
    letter-spacing: 2px;
    display: flex;
    align-items: center;
    gap: 10px;
}

.logo-icon {
    width: 40px;
    height: 40px;
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    border-radius: 8px;
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 20px;
    color: #fff;
}

.nav-menu {
    display: flex;
    gap: 35px;
}

.nav-link {
    color: #cccccc;
    font-size: 15px;
    font-weight: 500;
    position: relative;
    padding: 8px 0;
    transition: all 0.3s ease;
}

.nav-link::after {
    content: '';
    position: absolute;
    bottom: 0;
    left: 0;
    width: 0;
    height: 2px;
    background: linear-gradient(90deg, #667eea, #764ba2);
    transition: width 0.3s ease;
}

.nav-link:hover,
.nav-link.active {
    color: #ffffff;
}

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

/* 汉堡菜单 */
.hamburger {
    display: none;
    flex-direction: column;
    cursor: pointer;
    gap: 5px;
}

.hamburger span {
    width: 28px;
    height: 3px;
    background: #ffffff;
    border-radius: 2px;
    transition: all 0.3s ease;
}

.hamburger.active span:nth-child(1) {
    transform: rotate(45deg) translate(6px, 6px);
}

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

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

/* 移动端导航 */
@media (max-width: 768px) {
    .header-container {
        padding: 0 20px;
    }

    .hamburger {
        display: flex;
    }

    .nav-menu {
        position: fixed;
        top: 70px;
        left: -100%;
        width: 100%;
        height: calc(100vh - 70px);
        background: rgba(26, 26, 26, 0.98);
        flex-direction: column;
        align-items: center;
        justify-content: center;
        gap: 30px;
        transition: left 0.3s ease;
    }

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

    .nav-link {
        font-size: 20px;
    }
}

/* ========================================
   页脚
   ======================================== */
.footer {
    background: #1a1a1a;
    color: #999999;
    padding: 60px 0 30px;
}

.footer-container {
    max-width: 1400px;
    margin: 0 auto;
    padding: 0 40px;
}

.footer-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
    gap: 40px;
    margin-bottom: 40px;
}

.footer-section h4 {
    color: #ffffff;
    font-size: 18px;
    margin-bottom: 20px;
    font-weight: 600;
}

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

.footer-section ul li a:hover {
    color: #ffffff;
    padding-left: 5px;
}

.footer-bottom {
    border-top: 1px solid #333333;
    padding-top: 30px;
    text-align: center;
    font-size: 14px;
}

.footer-bottom a {
    color: #cccccc;
    margin: 0 10px;
}

.footer-bottom a:hover {
    color: #ffffff;
}

@media (max-width: 768px) {
    .footer-container {
        padding: 0 20px;
    }

    .footer-grid {
        grid-template-columns: 1fr;
        gap: 30px;
    }
}

/* ========================================
   通用动画
   ======================================== */
@keyframes fadeInUp {
    from {
        opacity: 0;
        transform: translateY(30px);
    }
    to {
        opacity: 1;
        transform: translateY(0);
    }
}

@keyframes fadeInLeft {
    from {
        opacity: 0;
        transform: translateX(-50px);
    }
    to {
        opacity: 1;
        transform: translateX(0);
    }
}

@keyframes fadeInRight {
    from {
        opacity: 0;
        transform: translateX(50px);
    }
    to {
        opacity: 1;
        transform: translateX(0);
    }
}

.animate-fade-in-up {
    animation: fadeInUp 0.6s ease forwards;
}

.animate-fade-in-left {
    animation: fadeInLeft 0.6s ease forwards;
}

.animate-fade-in-right {
    animation: fadeInRight 0.6s ease forwards;
}

/* 滚动渐入动画类 */
.scroll-reveal {
    opacity: 0;
    transform: translateY(30px);
    transition: all 0.6s ease;
}

.scroll-reveal.revealed {
    opacity: 1;
    transform: translateY(0);
}

/* ========================================
   按钮样式
   ======================================== */
.btn {
    display: inline-block;
    padding: 14px 32px;
    font-size: 15px;
    font-weight: 600;
    border-radius: 6px;
    cursor: pointer;
    transition: all 0.3s ease;
    border: none;
    text-transform: uppercase;
    letter-spacing: 1px;
}

.btn-primary {
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    color: #ffffff;
}

.btn-primary:hover {
    transform: translateY(-3px);
    box-shadow: 0 10px 30px rgba(102, 126, 234, 0.4);
}

.btn-secondary {
    background: transparent;
    color: #ffffff;
    border: 2px solid #ffffff;
}

.btn-secondary:hover {
    background: #ffffff;
    color: #1a1a1a;
}

.btn-outline {
    background: transparent;
    color: #1a1a1a;
    border: 2px solid #1a1a1a;
}

.btn-outline:hover {
    background: #1a1a1a;
    color: #ffffff;
}

/* ========================================
   卡片样式
   ======================================== */
.card {
    background: #ffffff;
    border-radius: 12px;
    overflow: hidden;
    box-shadow: 0 5px 20px rgba(0, 0, 0, 0.08);
    transition: all 0.3s ease;
}

.card:hover {
    transform: translateY(-8px);
    box-shadow: 0 15px 40px rgba(0, 0, 0, 0.12);
}

.card-image {
    width: 100%;
    height: 220px;
    object-fit: cover;
}

.card-content {
    padding: 25px;
}

.card-title {
    font-size: 18px;
    font-weight: 600;
    margin-bottom: 12px;
    color: #1a1a1a;
}

.card-text {
    font-size: 14px;
    color: #666666;
    line-height: 1.8;
    margin-bottom: 15px;
}

.card-meta {
    display: flex;
    justify-content: space-between;
    align-items: center;
    font-size: 13px;
    color: #999999;
}

/* ========================================
   对角斜线分割布局
   ======================================== */
.diagonal-section {
    position: relative;
    overflow: hidden;
}

.diagonal-section::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background: linear-gradient(135deg, #1a1a1a 0%, #2d2d2d 100%);
    clip-path: polygon(0 0, 100% 0, 100% 85%, 0 100%);
    z-index: -1;
}

.diagonal-section-light {
    position: relative;
    overflow: hidden;
}

.diagonal-section-light::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background: linear-gradient(135deg, #ffffff 0%, #f5f5f5 100%);
    clip-path: polygon(0 15%, 100% 0, 100% 100%, 0 100%);
    z-index: -1;
}

/* ========================================
   容器工具类
   ======================================== */
.container {
    max-width: 1400px;
    margin: 0 auto;
    padding: 0 40px;
}

.section-padding {
    padding: 100px 0;
}

.text-center {
    text-align: center;
}

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

.grid-2 {
    display: grid;
    grid-template-columns: repeat(2, 1fr);
    gap: 40px;
}

.grid-3 {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 30px;
}

.grid-4 {
    display: grid;
    grid-template-columns: repeat(4, 1fr);
    gap: 25px;
}

@media (max-width: 992px) {
    .grid-4 {
        grid-template-columns: repeat(2, 1fr);
    }
}

@media (max-width: 768px) {
    .container {
        padding: 0 20px;
    }

    .grid-2,
    .grid-3,
    .grid-4 {
        grid-template-columns: 1fr;
    }

    .section-padding {
        padding: 60px 0;
    }
}