/* ========================================
   Tech4Mods 网站建设 - 全局样式
   花店ins风：浅紫 + 浅粉 + 浅绿
   阶梯式错落叠加布局
======================================== */

:root {
    --color-primary: #d4a5d4;
    --color-secondary: #f8c8dc;
    --color-accent: #b8e6b8;
    --color-text: #4a4a4a;
    --color-bg: #faf9fc;
    --color-white: #ffffff;
    --shadow-soft: 0 4px 20px rgba(212, 165, 212, 0.15);
    --shadow-medium: 0 8px 30px rgba(212, 165, 212, 0.25);
    --transition-smooth: all 0.4s cubic-bezier(0.25, 0.46, 0.45, 0.94);
}

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

html {
    scroll-behavior: smooth;
}

body {
    font-family: 'Helvetica Neue', Arial, sans-serif;
    background: var(--color-bg);
    color: var(--color-text);
    line-height: 1.7;
    overflow-x: hidden;
}

a {
    text-decoration: none;
    color: inherit;
    transition: var(--transition-smooth);
}

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

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

/* ========================================
   顶部导航栏
======================================== */
.header {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    z-index: 1000;
    background: transparent;
    transition: var(--transition-smooth);
    padding: 25px 0;
}

.header.scrolled {
    background: rgba(255, 255, 255, 0.98);
    box-shadow: var(--shadow-soft);
    padding: 15px 0;
}

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

.logo {
    font-size: 28px;
    font-weight: 700;
    color: var(--color-primary);
    letter-spacing: 2px;
}

.logo span {
    color: var(--color-secondary);
}

.nav-menu {
    display: flex;
    list-style: none;
    gap: 35px;
}

.nav-menu li a {
    font-size: 15px;
    font-weight: 500;
    text-transform: uppercase;
    letter-spacing: 1px;
    position: relative;
    padding: 8px 0;
}

.nav-menu li a::after {
    content: '';
    position: absolute;
    bottom: 0;
    left: 0;
    width: 0;
    height: 2px;
    background: linear-gradient(90deg, var(--color-primary), var(--color-secondary));
    transition: var(--transition-smooth);
}

.nav-menu li a:hover::after {
    width: 100%;
}

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

.hamburger span {
    width: 28px;
    height: 3px;
    background: var(--color-primary);
    transition: var(--transition-smooth);
}

/* ========================================
   通用区块样式
======================================== */
.section {
    padding: 100px 0;
    position: relative;
}

.section-title {
    font-size: 42px;
    text-align: center;
    margin-bottom: 60px;
    color: var(--color-primary);
    font-weight: 300;
    letter-spacing: 3px;
}

.section-subtitle {
    text-align: center;
    font-size: 16px;
    color: #888;
    margin-top: -40px;
    margin-bottom: 60px;
    letter-spacing: 1px;
}

/* ========================================
   按钮样式
======================================== */
.btn {
    display: inline-block;
    padding: 15px 40px;
    background: linear-gradient(135deg, var(--color-primary), var(--color-secondary));
    color: var(--color-white);
    border-radius: 50px;
    font-size: 14px;
    font-weight: 600;
    letter-spacing: 1px;
    text-transform: uppercase;
    box-shadow: var(--shadow-soft);
    transition: var(--transition-smooth);
}

.btn:hover {
    transform: translateY(-3px);
    box-shadow: var(--shadow-medium);
}

.btn-outline {
    background: transparent;
    border: 2px solid var(--color-primary);
    color: var(--color-primary);
}

.btn-outline:hover {
    background: var(--color-primary);
    color: var(--color-white);
}

/* ========================================
   卡片样式
======================================== */
.card {
    background: var(--color-white);
    border-radius: 20px;
    overflow: hidden;
    box-shadow: var(--shadow-soft);
    transition: var(--transition-smooth);
}

.card:hover {
    transform: translateY(-10px);
    box-shadow: var(--shadow-medium);
}

.card-image {
    width: 100%;
    height: 250px;
    object-fit: cover;
}

.card-content {
    padding: 30px;
}

.card-title {
    font-size: 20px;
    margin-bottom: 15px;
    color: var(--color-primary);
}

.card-text {
    font-size: 14px;
    color: #666;
    line-height: 1.8;
}

/* ========================================
   页脚样式
======================================== */
.footer {
    background: linear-gradient(135deg, #f5f0f5, #fff0f5);
    padding: 80px 0 40px;
    margin-top: 100px;
}

.footer-grid {
    display: grid;
    grid-template-columns: repeat(4, 1fr);
    gap: 50px;
    margin-bottom: 60px;
}

.footer-section h4 {
    font-size: 18px;
    color: var(--color-primary);
    margin-bottom: 25px;
    letter-spacing: 1px;
}

.footer-section ul {
    list-style: none;
}

.footer-section ul li {
    margin-bottom: 12px;
}

.footer-section ul li a {
    color: #666;
    font-size: 14px;
}

.footer-section ul li a:hover {
    color: var(--color-primary);
}

.footer-bottom {
    text-align: center;
    padding-top: 40px;
    border-top: 1px solid rgba(212, 165, 212, 0.3);
    color: #888;
    font-size: 13px;
}

/* ========================================
   动画效果
======================================== */
.fade-in {
    opacity: 0;
    transform: translateY(30px);
    transition: var(--transition-smooth);
}

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

/* ========================================
   响应式设计
======================================== */
@media (max-width: 1024px) {
    .footer-grid {
        grid-template-columns: repeat(2, 1fr);
    }
}

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

    .nav-menu {
        position: fixed;
        top: 80px;
        left: -100%;
        width: 100%;
        height: calc(100vh - 80px);
        background: var(--color-white);
        flex-direction: column;
        align-items: center;
        justify-content: center;
        transition: var(--transition-smooth);
    }

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

    .hamburger {
        display: flex;
    }

    .section-title {
        font-size: 32px;
    }

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