/* ============================================================
   ABOUT.CSS - Company Profile Page
   Mobile First + Story + Timeline + Advantages
   ============================================================ */

:root {
    --primary: #e63946;
    --primary-dark: #c1121f;
    --secondary: #1d3557;
    --accent: #f4a261;
    --white: #ffffff;
    --light: #f8f9fa;
    --light-blue: #e8f4f8;
    --text-dark: #1a1a2e;
    --text-muted: #6c757d;
    --gradient-warm: linear-gradient(135deg, #fff5f5 0%, #fef3e2 100%);
    --gradient-cool: linear-gradient(135deg, #e8f4f8 0%, #f0f4ff 100%);
    --gradient-primary: linear-gradient(135deg, #e63946 0%, #f4a261 100%);
    --gradient-dark: linear-gradient(135deg, #1d3557 0%, #457b9d 100%);
    --space-xs: 0.5rem;
    --space-sm: 1rem;
    --space-md: 1.5rem;
    --space-lg: 2rem;
    --space-xl: 3rem;
    --space-xxl: 4rem;
    --radius-sm: 8px;
    --radius-md: 12px;
    --radius-lg: 20px;
    --radius-full: 50px;
    --shadow-sm: 0 2px 8px rgba(0,0,0,0.08);
    --shadow-md: 0 4px 20px rgba(0,0,0,0.12);
    --shadow-lg: 0 8px 40px rgba(0,0,0,0.15);
    --transition: all 0.3s ease;
}

*, *::before, *::after { box-sizing: border-box; margin: 0; padding: 0; }
html { scroll-behavior: smooth; }
body { font-family: 'Segoe UI', -apple-system, sans-serif; line-height: 1.6; color: var(--text-dark); background: var(--white); overflow-x: hidden; }
html, body { max-width: 100vw; overflow-x: hidden; }
img { max-width: 100%; height: auto; display: block; }
a { text-decoration: none; color: inherit; transition: var(--transition); }
ul { list-style: none; }
.container { width: 100%; max-width: 1280px; margin: 0 auto; padding: 0 20px; }

/* ==================== HEADER ==================== */
.header { position: fixed; top: 0; left: 0; right: 0; z-index: 1000; background: var(--white); box-shadow: var(--shadow-sm); }
.header-container { display: flex; align-items: center; justify-content: space-between; padding: 10px 15px; max-width: 1280px; margin: 0 auto; }
.logo { flex-shrink: 0; }
.logo img { height: 36px; width: auto; }
.nav-toggle { display: flex; flex-direction: column; justify-content: center; align-items: center; width: 48px; height: 48px; background: var(--primary); border: none; border-radius: var(--radius-sm); cursor: pointer; z-index: 1001; box-shadow: var(--shadow-sm); }
.hamburger { width: 22px; height: 3px; background: var(--white); position: relative; border-radius: 2px; transition: var(--transition); }
.hamburger::before, .hamburger::after { content: ''; position: absolute; width: 22px; height: 3px; background: var(--white); border-radius: 2px; transition: var(--transition); }
.hamburger::before { top: -7px; }
.hamburger::after { top: 7px; }
.nav-toggle.active { background: var(--secondary); }
.nav-toggle.active .hamburger { background: transparent; }
.nav-toggle.active .hamburger::before { transform: rotate(45deg); top: 0; }
.nav-toggle.active .hamburger::after { transform: rotate(-45deg); top: 0; }
.nav-menu { position: fixed; top: 0; right: -100%; width: 80%; max-width: 320px; height: 100vh; background: var(--white); box-shadow: var(--shadow-lg); padding: 80px var(--space-md) var(--space-lg); transition: right 0.4s ease; overflow-y: auto; }
.nav-menu.active { right: 0; }
.nav-list { display: flex; flex-direction: column; gap: var(--space-xs); }
.nav-link { display: block; padding: var(--space-sm) var(--space-md); font-size: 1rem; font-weight: 500; color: var(--text-dark); border-radius: var(--radius-sm); }
.nav-link:hover, .nav-link.active { background: var(--light-blue); color: var(--primary); }
.nav-link.nav-cta { background: var(--gradient-primary); color: var(--white); text-align: center; margin-top: var(--space-sm); }

/* ==================== ABOUT HERO ==================== */
.about-hero {
    position: relative;
    padding: calc(80px + var(--space-xxl)) 0 var(--space-xxl);
    /*background: url('https://www.thehammer.cn/static/hengda/banner1.jpg') center/cover no-repeat;*/
    min-height: 50vh;
    display: flex;
    align-items: center;
}
.hero-overlay {
    position: absolute;
    inset: 0;
    background: linear-gradient(135deg, rgba(29,53,87,0.9) 0%, rgba(29,53,87,0.7) 100%);
}
.about-hero .container { position: relative; z-index: 1; }
.hero-content { max-width: 700px; }
.hero-tag {
    display: inline-block;
    background: var(--accent);
    color: var(--secondary);
    padding: 6px 16px;
    border-radius: var(--radius-full);
    font-size: 0.75rem;
    font-weight: 700;
    text-transform: uppercase;
    margin-bottom: var(--space-md);
}
.about-hero h1 {
    font-size: 1.75rem;
    color: var(--white);
    line-height: 1.2;
    margin-bottom: var(--space-md);
}
.about-hero h1 span { color: var(--accent); }
.about-hero p { color: rgba(255,255,255,0.85); font-size: 0.95rem; line-height: 1.8; }

/* ==================== STATS SECTION ==================== */
.stats-section {
    padding: var(--space-xl) 0;
    background: var(--gradient-primary);
    margin-top: -1px;
}
.stats-row {
    display: grid;
    grid-template-columns: repeat(2, 1fr);
    gap: var(--space-md);
}
.stat-box {
    text-align: center;
    padding: var(--space-md);
}
.stat-number {
    font-size: 2.5rem;
    font-weight: 700;
    color: var(--white);
    line-height: 1;
    margin-bottom: var(--space-xs);
}
.stat-label {
    font-size: 0.8rem;
    color: rgba(255,255,255,0.85);
    text-transform: uppercase;
    letter-spacing: 1px;
}

/* ==================== STORY SECTION ==================== */
.story-section {
    padding: var(--space-xxl) 0;
    background: var(--white);
}
.story-grid {
    display: grid;
    gap: var(--space-xl);
}
.story-image {
    position: relative;
    border-radius: var(--radius-lg);
    overflow: hidden;
}
.story-image img { width: 100%; height: auto; }
.image-badge {
    position: absolute;
    bottom: var(--space-md);
    left: var(--space-md);
    background: var(--white);
    padding: 10px 16px;
    border-radius: var(--radius-sm);
    display: flex;
    align-items: center;
    gap: var(--space-xs);
    box-shadow: var(--shadow-md);
}
.image-badge i { color: var(--primary); }
.image-badge span { font-size: 0.8rem; font-weight: 600; color: var(--secondary); }

.section-tag {
    display: inline-block;
    background: var(--light-blue);
    color: var(--primary);
    padding: 6px 16px;
    border-radius: var(--radius-full);
    font-size: 0.7rem;
    font-weight: 600;
    text-transform: uppercase;
    letter-spacing: 1px;
    margin-bottom: var(--space-sm);
}
.story-content h2 {
    font-size: 1.5rem;
    color: var(--secondary);
    margin-bottom: var(--space-md);
}
.story-content p {
    color: var(--text-muted);
    margin-bottom: var(--space-md);
    line-height: 1.8;
}
.story-features {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: var(--space-sm);
    margin-top: var(--space-lg);
}
.feature-item {
    display: flex;
    flex-direction: column;
    align-items: center;
    text-align: center;
    padding: var(--space-sm);
    background: var(--light);
    border-radius: var(--radius-sm);
}
.feature-item i { font-size: 1.25rem; color: var(--primary); margin-bottom: var(--space-xs); }
.feature-item span { font-size: 0.75rem; font-weight: 600; color: var(--secondary); }

/* ==================== VISION BANNER ==================== */
.vision-banner {
    padding: var(--space-xxl) 0;
    background: linear-gradient(135deg, #e0f2fe 0%, #bae6fd 50%, #e0f2fe 100%);
    position: relative;
    overflow: hidden;
}
.vision-banner::before {
    content: '';
    position: absolute;
    top: -50%;
    left: -50%;
    width: 200%;
    height: 200%;
    background: radial-gradient(circle, rgba(59,130,246,0.1) 0%, transparent 50%);
    animation: pulse-bg 8s ease-in-out infinite;
}
@keyframes pulse-bg {
    0%, 100% { transform: scale(1); opacity: 0.5; }
    50% { transform: scale(1.1); opacity: 0.8; }
}
.vision-content {
    position: relative;
    z-index: 1;
    max-width: 900px;
    margin: 0 auto;
    text-align: center;
}
.quote-mark {
    margin-bottom: var(--space-md);
}
.quote-mark i {
    font-size: 2.5rem;
    color: var(--primary);
    opacity: 0.4;
}
.vision-text {
    font-size: 1.25rem;
    line-height: 2;
    color: #000000;
    font-weight: 700;
    letter-spacing: 0.3px;
}
.vision-signature {
    display: flex;
    align-items: center;
    justify-content: center;
    gap: var(--space-md);
    margin-top: var(--space-xl);
}
.signature-line {
    width: 60px;
    height: 2px;
    background: linear-gradient(90deg, transparent, var(--primary), transparent);
}
.signature-text {
    font-size: 0.85rem;
    font-weight: 600;
    color: var(--primary);
    text-transform: uppercase;
    letter-spacing: 2px;
}

/* ==================== TIMELINE SECTION ==================== */
.timeline-section {
    padding: var(--space-xxl) 0;
    background: var(--gradient-cool);
}
.section-header {
    text-align: center;
    margin-bottom: var(--space-xl);
}
.section-header h2 {
    font-size: 1.5rem;
    color: var(--secondary);
    margin-bottom: var(--space-xs);
}
.section-header p { color: var(--text-muted); }
.section-header.light h2 { color: var(--white); }
.section-header.light p { color: rgba(255,255,255,0.8); }

.timeline-wrapper {
    overflow-x: auto;
    padding-bottom: var(--space-sm);
    -webkit-overflow-scrolling: touch;
}
.timeline-track {
    display: flex;
    gap: var(--space-md);
    min-width: max-content;
    padding: var(--space-sm) 0;
}
.timeline-item {
    flex-shrink: 0;
    width: 200px;
    background: var(--white);
    border-radius: var(--radius-md);
    padding: var(--space-md);
    box-shadow: var(--shadow-sm);
    position: relative;
}
.timeline-year {
    display: inline-block;
    background: var(--primary);
    color: var(--white);
    padding: 4px 12px;
    border-radius: var(--radius-full);
    font-size: 0.8rem;
    font-weight: 700;
    margin-bottom: var(--space-sm);
}
.timeline-content h4 {
    font-size: 0.95rem;
    color: var(--secondary);
    margin-bottom: 4px;
}
.timeline-content p {
    font-size: 0.8rem;
    color: var(--text-muted);
    line-height: 1.5;
}

/* ==================== ADVANTAGES SECTION ==================== */
.advantages-section {
    padding: var(--space-xxl) 0;
    background: var(--secondary);
}
.advantages-grid {
    display: grid;
    grid-template-columns: repeat(2, 1fr);
    gap: var(--space-md);
}
.adv-card {
    background: rgba(255,255,255,0.1);
    border-radius: var(--radius-md);
    padding: var(--space-lg);
    text-align: center;
    transition: var(--transition);
}
.adv-card:hover {
    background: rgba(255,255,255,0.15);
    transform: translateY(-5px);
}
.adv-icon {
    width: 60px;
    height: 60px;
    margin: 0 auto var(--space-md);
    background: var(--gradient-primary);
    border-radius: 50%;
    display: flex;
    justify-content: center;
    align-items: center;
    font-size: 1.5rem;
    color: var(--white);
}
.adv-card h3 {
    font-size: 1rem;
    color: var(--white);
    margin-bottom: var(--space-xs);
}
.adv-card p {
    font-size: 0.85rem;
    color: rgba(255,255,255,0.75);
    line-height: 1.6;
}

/* ==================== GLOBAL SECTION ==================== */
.global-section {
    padding: var(--space-xxl) 0;
    background: var(--white);
}
.regions-grid {
    display: grid;
    grid-template-columns: repeat(2, 1fr);
    gap: var(--space-md);
}
.region-item {
    background: var(--light);
    border-radius: var(--radius-md);
    padding: var(--space-lg);
    text-align: center;
    transition: var(--transition);
}
.region-item:hover {
    box-shadow: var(--shadow-md);
    transform: translateY(-3px);
}
.region-flag {
    font-size: 2.5rem;
    margin-bottom: var(--space-sm);
}
.region-item h4 {
    font-size: 1rem;
    color: var(--secondary);
    margin-bottom: var(--space-xs);
}
.region-item p {
    font-size: 0.8rem;
    color: var(--text-muted);
    line-height: 1.5;
}

/* ==================== CTA SECTION ==================== */
.cta-section {
    padding: var(--space-xxl) 0;
    background: var(--gradient-warm);
    text-align: center;
}
.cta-content h2 {
    font-size: 1.5rem;
    color: var(--secondary);
    margin-bottom: var(--space-xs);
}
.cta-content > p {
    color: var(--text-muted);
    margin-bottom: var(--space-lg);
}
.cta-buttons {
    display: flex;
    flex-direction: column;
    gap: var(--space-sm);
    align-items: center;
}
.btn {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    gap: var(--space-xs);
    padding: var(--space-sm) var(--space-xl);
    font-size: 0.95rem;
    font-weight: 600;
    border-radius: var(--radius-full);
    transition: var(--transition);
}
.btn-primary { background: var(--primary); color: var(--white); }
.btn-primary:hover { background: var(--primary-dark); transform: translateY(-3px); }
.btn-outline { background: transparent; border: 2px solid var(--secondary); color: var(--secondary); }
.btn-outline:hover { background: var(--secondary); color: var(--white); }

/* ==================== FOOTER ==================== */
.footer { background: linear-gradient(135deg, #e3f2fd 0%, #bbdefb 50%, #90caf9 100%); color: var(--text-dark); padding: var(--space-xxl) 0 var(--space-lg); }
.footer-grid { display: grid; gap: var(--space-lg); margin-bottom: var(--space-xl); }
.footer-col h4 { font-size: 1rem; margin-bottom: var(--space-md); color: var(--primary); font-weight: 700; }
.footer-col ul li { margin-bottom: var(--space-sm); }
.footer-col a { color: var(--text-dark); font-weight: 700; }
.footer-col a:hover { color: var(--primary); padding-left: 5px; }
.contact-list li { display: flex; align-items: center; gap: var(--space-sm); color: var(--text-dark); font-weight: 700; }
.contact-list i { color: var(--primary); width: 20px; }
.footer-bottom { text-align: center; padding-top: var(--space-lg); border-top: 1px solid rgba(0,0,0,0.08); }
.footer-bottom p { color: var(--text-dark); font-weight: 700; font-size: 0.875rem; }

.back-to-top { position: fixed; bottom: 20px; right: 20px; width: 50px; height: 50px; background: var(--primary); color: var(--white); border: none; border-radius: 50%; cursor: pointer; opacity: 0; visibility: hidden; transition: var(--transition); z-index: 999; box-shadow: var(--shadow-md); }
.back-to-top.visible { opacity: 1; visibility: visible; }
.back-to-top:hover { background: var(--primary-dark); transform: translateY(-5px); }

/* ==================== TABLET (768px+) ==================== */
@media (min-width: 768px) {
    .header-container { padding: 8px 20px; }
    .logo img { height: 32px; }
    .nav-toggle { display: none; }
    .nav-menu { position: static; width: auto; height: auto; background: transparent; box-shadow: none; padding: 0; overflow: visible; }
    .nav-list { flex-direction: row; gap: 0; }
    .nav-link { padding: 4px 3px; font-size: 0.65rem; white-space: nowrap; }
    .nav-link:hover, .nav-link.active { background: transparent; color: var(--primary); }
    .nav-link.nav-cta { margin-top: 0; margin-left: 2px; padding: 4px 6px; font-size: 0.65rem; background: var(--primary); color: var(--white); }
    .nav-link.nav-cta:hover, .nav-link.nav-cta.active { background: var(--primary-dark); color: var(--white); }
    
    .about-hero h1 { font-size: 2.25rem; }
    .stats-row { grid-template-columns: repeat(4, 1fr); }
    .story-grid { grid-template-columns: 1fr 1fr; align-items: center; }
    .advantages-grid { grid-template-columns: repeat(4, 1fr); }
    .regions-grid { grid-template-columns: repeat(4, 1fr); }
    .cta-buttons { flex-direction: row; }
    .footer-grid { grid-template-columns: repeat(3, 1fr); }
}

/* ==================== DESKTOP (1024px+) ==================== */
@media (min-width: 1024px) {
    .header-container { padding: 10px 30px; gap: 40px; justify-content: flex-start; }
    .nav-menu { margin-left: 0; }
    .nav-list { gap: 5px; }
    .logo img { height: 46px; }
    .nav-link { padding: 8px 12px; font-size: 0.92rem; }
    .nav-link.nav-cta { padding: 8px 18px; font-size: 0.92rem; }
    
    .about-hero { min-height: 60vh; padding: calc(90px + var(--space-xxl)) 0 var(--space-xxl); }
    .about-hero h1 { font-size: 2.75rem; }
    .about-hero p { font-size: 1.1rem; }
    
    .stat-number { font-size: 3rem; }
    
    .story-content h2 { font-size: 2rem; }
    .story-features { gap: var(--space-md); }
    
    .section-header h2 { font-size: 2rem; }
    
    .timeline-item { width: 240px; }
    
    .cta-content h2 { font-size: 2rem; }
}