/* ========== 全局重置与基础 ========== */
*, *::before, *::after {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

:root {
    --primary: #4CAF50;
    --primary-dark: #388E3C;
    --primary-light: #81C784;
    --bg-light: #E8F5E9;
    --accent: #FF6B35;
    --accent-hover: #E55A2B;
    --text-dark: #333333;
    --text-mid: #666666;
    --text-light: #999999;
    --border: #e5e5e5;
    --white: #ffffff;
    --shadow: 0 4px 20px rgba(76,175,80,0.15);
    --shadow-lg: 0 8px 40px rgba(76,175,80,0.2);
    --radius: 16px;
    --radius-sm: 10px;
    --transition: all 0.3s cubic-bezier(0.4, 0, 0.2, 1);
}

html {
    scroll-behavior: smooth;
}

body {
    font-family: 'Noto Sans SC', -apple-system, BlinkMacSystemFont, sans-serif;
    color: var(--text-dark);
    background: var(--white);
    line-height: 1.6;
    -webkit-font-smoothing: antialiased;
}

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

ul {
    list-style: none;
}

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

.container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 20px;
}

.section {
    padding: 100px 0;
}

.section-header {
    text-align: center;
    margin-bottom: 60px;
}

.section-tag {
    display: inline-block;
    font-size: 12px;
    font-weight: 600;
    color: var(--primary);
    text-transform: uppercase;
    letter-spacing: 3px;
    padding: 4px 16px;
    border: 1px solid var(--primary-light);
    border-radius: 20px;
    margin-bottom: 16px;
}

.section-title {
    font-size: 36px;
    font-weight: 700;
    color: var(--text-dark);
    margin-bottom: 16px;
    position: relative;
}

.section-title::after {
    content: '';
    display: block;
    width: 60px;
    height: 4px;
    background: var(--primary);
    border-radius: 2px;
    margin: 16px auto 0;
}

.section-desc {
    font-size: 16px;
    color: var(--text-mid);
    max-width: 600px;
    margin: 0 auto;
}

/* ========== 导航栏 ========== */
.navbar {
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    z-index: 1000;
    background: rgba(255,255,255,0.95);
    backdrop-filter: blur(20px);
    -webkit-backdrop-filter: blur(20px);
    border-bottom: 1px solid transparent;
    transition: var(--transition);
}

.navbar.scrolled {
    border-bottom-color: var(--border);
    box-shadow: 0 2px 20px rgba(0,0,0,0.06);
}

.nav-container {
    display: flex;
    align-items: center;
    justify-content: space-between;
    height: 70px;
}

.nav-brand {
    display: flex;
    align-items: center;
    gap: 10px;
}

.nav-logo-icon {
    width: 32px;
    height: 32px;
}

.nav-logo-text {
    font-size: 20px;
    font-weight: 700;
    color: var(--primary);
}

.nav-links {
    display: flex;
    align-items: center;
    gap: 8px;
}

.nav-links a {
    font-size: 14px;
    font-weight: 500;
    color: var(--text-mid);
    padding: 8px 16px;
    border-radius: 8px;
    transition: var(--transition);
}

.nav-links a:hover,
.nav-links a.active {
    color: var(--primary);
    background: var(--bg-light);
}

.nav-toggle {
    display: none;
    flex-direction: column;
    gap: 5px;
    cursor: pointer;
    padding: 8px;
}

.nav-toggle span {
    display: block;
    width: 24px;
    height: 2px;
    background: var(--text-dark);
    border-radius: 2px;
    transition: var(--transition);
}

/* ========== Hero区 ========== */
.hero {
    min-height: 100vh;
    display: flex;
    align-items: center;
    background: linear-gradient(135deg, var(--bg-light) 0%, var(--white) 50%, var(--bg-light) 100%);
    position: relative;
    overflow: hidden;
    padding-top: 70px;
}

.hero-container {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 60px;
    align-items: center;
}

.hero-content {
    padding: 40px 0;
}

.hero-logo {
    width: 280px;
    margin-bottom: 30px;
}

.hero-title {
    font-size: 48px;
    font-weight: 900;
    color: var(--text-dark);
    line-height: 1.2;
    margin-bottom: 16px;
}

.hero-subtitle {
    font-size: 18px;
    color: var(--text-mid);
    margin-bottom: 36px;
    line-height: 1.6;
}

.hero-actions {
    display: flex;
    gap: 16px;
}

.btn {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    padding: 14px 32px;
    font-size: 15px;
    font-weight: 600;
    border-radius: var(--radius-sm);
    border: none;
    cursor: pointer;
    transition: var(--transition);
    text-decoration: none;
}

.btn-primary {
    background: var(--primary);
    color: var(--white);
    box-shadow: var(--shadow);
}

.btn-primary:hover {
    background: var(--primary-dark);
    transform: translateY(-2px);
    box-shadow: var(--shadow-lg);
}

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

.btn-secondary:hover {
    background: var(--bg-light);
    transform: translateY(-2px);
}

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

.apple-illustration {
    animation: float 3s ease-in-out infinite;
}

@keyframes float {
    0%, 100% { transform: translateY(0); }
    50% { transform: translateY(-20px); }
}

.scroll-indicator {
    position: absolute;
    bottom: 30px;
    left: 50%;
    transform: translateX(-50%);
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: 8px;
    color: var(--text-light);
    font-size: 12px;
    animation: bounce 2s infinite;
}

.scroll-arrow {
    width: 20px;
    height: 20px;
    border-right: 2px solid var(--text-light);
    border-bottom: 2px solid var(--text-light);
    transform: rotate(45deg);
}

@keyframes bounce {
    0%, 100% { transform: translateX(-50%) translateY(0); }
    50% { transform: translateX(-50%) translateY(10px); }
}

/* ========== 品牌概览 ========== */
.brand-overview {
    background: var(--white);
}

.brand-grid {
    display: grid;
    grid-template-columns: repeat(4, 1fr);
    gap: 24px;
}

.brand-card {
    background: var(--white);
    padding: 36px 24px;
    border-radius: var(--radius);
    box-shadow: 0 2px 20px rgba(0,0,0,0.04);
    border: 1px solid var(--border);
    transition: var(--transition);
    text-align: center;
}

.brand-card:hover {
    transform: translateY(-6px);
    box-shadow: var(--shadow);
    border-color: var(--primary-light);
}

.card-icon {
    width: 64px;
    height: 64px;
    margin: 0 auto 20px;
    display: flex;
    align-items: center;
    justify-content: center;
}

.brand-card h3 {
    font-size: 20px;
    font-weight: 600;
    margin-bottom: 12px;
    color: var(--text-dark);
}

.brand-card p {
    font-size: 14px;
    color: var(--text-mid);
    line-height: 1.6;
}

/* ========== 标志规范 ========== */
.logo-section {
    background: var(--bg-light);
}

.logo-showcase {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 24px;
    margin-bottom: 48px;
}

.logo-card {
    background: var(--white);
    padding: 32px 24px;
    border-radius: var(--radius);
    box-shadow: 0 2px 20px rgba(0,0,0,0.04);
    text-align: center;
    transition: var(--transition);
}

.logo-card:hover {
    transform: translateY(-4px);
    box-shadow: var(--shadow);
}

.logo-card-dark {
    background: #2E7D32;
    color: var(--white);
}

.logo-card-dark p {
    color: rgba(255,255,255,0.8);
}

.logo-card h3 {
    font-size: 16px;
    font-weight: 600;
    margin-bottom: 20px;
}

.logo-preview {
    min-height: 80px;
    display: flex;
    align-items: center;
    justify-content: center;
    margin-bottom: 16px;
}

.demo-logo {
    max-width: 200px;
    max-height: 60px;
}

.demo-logo-vertical {
    max-height: 100px;
}

.demo-logo-icon {
    width: 60px;
    height: 60px;
}

.logo-guidelines {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 24px;
}

.guideline-item {
    background: var(--white);
    padding: 24px;
    border-radius: var(--radius);
    box-shadow: 0 2px 20px rgba(0,0,0,0.04);
}

.guideline-item h4 {
    font-size: 16px;
    font-weight: 600;
    margin-bottom: 16px;
    color: var(--text-dark);
}

.guideline-visual {
    margin-bottom: 12px;
}

.guideline-item p {
    font-size: 13px;
    color: var(--text-mid);
}

/* ========== 色彩规范 ========== */
.color-section {
    background: var(--white);
}

.color-palette {
    display: grid;
    grid-template-columns: 1fr 2fr 2fr;
    gap: 32px;
    margin-bottom: 48px;
}

.color-group h3 {
    font-size: 18px;
    font-weight: 600;
    margin-bottom: 16px;
    color: var(--text-dark);
}

.color-swatch {
    display: flex;
    align-items: center;
    gap: 16px;
    padding: 12px;
    border-radius: var(--radius-sm);
    background: var(--white);
    border: 1px solid var(--border);
    margin-bottom: 12px;
    transition: var(--transition);
}

.color-swatch:hover {
    border-color: var(--primary-light);
    box-shadow: 0 2px 12px rgba(76,175,80,0.1);
}

.color-preview {
    width: 48px;
    height: 48px;
    border-radius: 10px;
    flex-shrink: 0;
}

.primary-color .color-preview {
    width: 64px;
    height: 64px;
}

.color-info {
    display: flex;
    flex-direction: column;
    gap: 2px;
}

.color-name {
    font-size: 14px;
    font-weight: 600;
    color: var(--text-dark);
}

.color-hex {
    font-size: 12px;
    font-weight: 500;
    color: var(--text-mid);
    font-family: 'Courier New', monospace;
    text-transform: uppercase;
}

.color-rgb,
.color-cmyk {
    font-size: 11px;
    color: var(--text-light);
    font-family: 'Courier New', monospace;
}

.color-usage {
    background: var(--bg-light);
    padding: 32px;
    border-radius: var(--radius);
}

.color-usage h3 {
    font-size: 18px;
    font-weight: 600;
    margin-bottom: 20px;
}

.usage-grid {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 12px;
}

.usage-item {
    display: flex;
    align-items: center;
    gap: 12px;
    font-size: 14px;
    color: var(--text-mid);
}

.usage-dot {
    width: 12px;
    height: 12px;
    border-radius: 50%;
    flex-shrink: 0;
}

/* ========== 字体规范 ========== */
.typography-section {
    background: var(--bg-light);
}

.type-showcase {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 32px;
    margin-bottom: 48px;
}

.type-group {
    background: var(--white);
    padding: 32px;
    border-radius: var(--radius);
    box-shadow: 0 2px 20px rgba(0,0,0,0.04);
}

.type-group h3 {
    font-size: 16px;
    font-weight: 600;
    margin-bottom: 24px;
    color: var(--text-dark);
    padding-bottom: 12px;
    border-bottom: 2px solid var(--bg-light);
}

.type-sample {
    display: flex;
    flex-direction: column;
    gap: 16px;
}

.type-line {
    padding: 8px 0;
}

.type-table {
    background: var(--white);
    padding: 32px;
    border-radius: var(--radius);
    box-shadow: 0 2px 20px rgba(0,0,0,0.04);
}

.type-table h3 {
    font-size: 18px;
    font-weight: 600;
    margin-bottom: 20px;
}

table {
    width: 100%;
    border-collapse: collapse;
}

thead th {
    background: var(--bg-light);
    padding: 12px 16px;
    font-size: 13px;
    font-weight: 600;
    color: var(--text-mid);
    text-align: left;
    border-bottom: 2px solid var(--border);
}

tbody td {
    padding: 12px 16px;
    font-size: 14px;
    color: var(--text-dark);
    border-bottom: 1px solid var(--border);
}

tbody tr:hover {
    background: var(--bg-light);
}

/* ========== 应用展示 ========== */
.mockup-section {
    background: var(--white);
}

.mockup-grid {
    display: grid;
    grid-template-columns: repeat(2, 1fr);
    gap: 24px;
}

.mockup-card {
    background: var(--white);
    padding: 24px;
    border-radius: var(--radius);
    box-shadow: 0 2px 20px rgba(0,0,0,0.04);
    border: 1px solid var(--border);
    transition: var(--transition);
    text-align: center;
}

.mockup-card:hover {
    transform: translateY(-4px);
    box-shadow: var(--shadow);
    border-color: var(--primary-light);
}

.mockup-card h3 {
    font-size: 16px;
    font-weight: 600;
    margin-bottom: 16px;
    color: var(--text-dark);
}

.mockup-preview {
    min-height: 200px;
    display: flex;
    align-items: center;
    justify-content: center;
    margin-bottom: 16px;
    background: var(--bg-light);
    border-radius: var(--radius-sm);
    padding: 20px;
}

.mockup-img {
    max-width: 100%;
    max-height: 200px;
}

.mockup-card p {
    font-size: 13px;
    color: var(--text-light);
}

/* ========== 页脚 ========== */
.footer {
    background: #1B5E20;
    color: var(--white);
    padding: 60px 0 30px;
}

.footer-container {
    display: flex;
    flex-direction: column;
    gap: 40px;
}

.footer-brand {
    display: flex;
    flex-direction: column;
    align-items: center;
    text-align: center;
    gap: 16px;
}

.footer-logo {
    width: 200px;
}

.footer-desc {
    font-size: 14px;
    color: rgba(255,255,255,0.7);
    max-width: 400px;
}

.footer-links {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 40px;
}

.footer-col h4 {
    font-size: 14px;
    font-weight: 600;
    margin-bottom: 16px;
    color: var(--white);
}

.footer-col ul {
    display: flex;
    flex-direction: column;
    gap: 8px;
}

.footer-col a {
    font-size: 13px;
    color: rgba(255,255,255,0.6);
    transition: var(--transition);
}

.footer-col a:hover {
    color: var(--white);
    padding-left: 4px;
}

.footer-bottom {
    text-align: center;
    padding-top: 30px;
    border-top: 1px solid rgba(255,255,255,0.1);
}

.footer-bottom p {
    font-size: 12px;
    color: rgba(255,255,255,0.5);
}

/* ========== 响应式 ========== */
@media (max-width: 992px) {
    .hero-container {
        grid-template-columns: 1fr;
        text-align: center;
    }
    
    .hero-actions {
        justify-content: center;
    }
    
    .hero-visual {
        display: none;
    }
    
    .brand-grid {
        grid-template-columns: repeat(2, 1fr);
    }
    
    .logo-showcase {
        grid-template-columns: repeat(2, 1fr);
    }
    
    .color-palette {
        grid-template-columns: 1fr;
    }
    
    .type-showcase {
        grid-template-columns: 1fr;
    }
    
    .footer-links {
        grid-template-columns: repeat(2, 1fr);
    }
}

@media (max-width: 768px) {
    .section {
        padding: 60px 0;
    }
    
    .section-title {
        font-size: 28px;
    }
    
    .hero-title {
        font-size: 36px;
    }
    
    .hero-logo {
        width: 220px;
    }
    
    .nav-links {
        position: fixed;
        top: 70px;
        left: 0;
        right: 0;
        background: var(--white);
        flex-direction: column;
        padding: 20px;
        gap: 4px;
        box-shadow: 0 10px 30px rgba(0,0,0,0.1);
        transform: translateY(-100%);
        opacity: 0;
        pointer-events: none;
        transition: var(--transition);
    }
    
    .nav-links.active {
        transform: translateY(0);
        opacity: 1;
        pointer-events: all;
    }
    
    .nav-links a {
        display: block;
        padding: 12px 16px;
        font-size: 16px;
    }
    
    .nav-toggle {
        display: flex;
    }
    
    .brand-grid {
        grid-template-columns: 1fr;
    }
    
    .logo-showcase {
        grid-template-columns: 1fr;
    }
    
    .logo-guidelines {
        grid-template-columns: 1fr;
    }
    
    .mockup-grid {
        grid-template-columns: 1fr;
    }
    
    .usage-grid {
        grid-template-columns: 1fr;
    }
    
    .footer-links {
        grid-template-columns: 1fr;
        text-align: center;
    }
}

@media (max-width: 480px) {
    .hero-title {
        font-size: 28px;
    }
    
    .hero-subtitle {
        font-size: 15px;
    }
    
    .btn {
        padding: 12px 24px;
        font-size: 14px;
    }
    
    .section-title {
        font-size: 24px;
    }
}