/* ==========================================
   信税开票平台 - 首页样式
   配色规范（黑白蓝三色）：
   - 主色   #2563EB  (品牌蓝)
   - 深墨   #0F172A  (文字/深色元素)
   - 中性色 白/浅灰背景
   ========================================== */

:root {
    --primary: #2563EB;
    --primary-dark: #1E4FD6;
    --primary-soft: #EFF4FE;
    --accent: #2563EB;
    --accent-soft: #EFF4FE;
    --ink: #0F172A;
    --ink-2: #475569;
    --ink-3: #94A3B8;
    --bg: #FFFFFF;
    --bg-soft: #F8FAFC;
    --line: #E2E8F0;
    --radius: 14px;
    --shadow: 0 10px 30px rgba(15, 23, 42, 0.06);
    --shadow-lg: 0 20px 50px rgba(15, 23, 42, 0.10);
    --maxw: 1160px;
}

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

html { scroll-behavior: smooth; }

body {
    font-family: -apple-system, BlinkMacSystemFont, "PingFang SC", "Hiragino Sans GB", "Microsoft YaHei", "Segoe UI", sans-serif;
    color: var(--ink);
    background: var(--bg);
    line-height: 1.6;
    -webkit-font-smoothing: antialiased;
}

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

/* ========== 导航栏 ========== */
.navbar {
    position: sticky;
    top: 0;
    z-index: 100;
    background: rgba(255, 255, 255, 0.92);
    backdrop-filter: blur(12px);
    -webkit-backdrop-filter: blur(12px);
    border-bottom: 1px solid var(--line);
    transition: box-shadow 0.3s;
}

.nav-container {
    max-width: var(--maxw);
    margin: 0 auto;
    padding: 0 24px;
    height: 66px;
    display: flex;
    align-items: center;
    justify-content: space-between;
}

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

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

.brand-name {
    font-size: 20px;
    font-weight: 700;
    letter-spacing: 0.5px;
    color: var(--ink);
}

.nav-menu {
    display: flex;
    align-items: center;
    gap: 6px;
    font-size: 15px;
}

.nav-menu > a {
    padding: 8px 14px;
    border-radius: 8px;
    color: var(--ink-2);
    transition: color 0.2s, background 0.2s;
}

.nav-menu > a:hover {
    color: var(--primary);
    background: var(--primary-soft);
}

.nav-divider {
    width: 1px;
    height: 20px;
    background: var(--line);
    margin: 0 10px;
}

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

.user-info-link {
    display: flex;
    align-items: center;
    gap: 7px;
    padding: 6px 10px;
    border-radius: 8px;
    color: var(--ink);
}

.user-info-link:hover { background: var(--primary-soft); }

.user-avatar {
    display: flex;
    align-items: center;
    justify-content: center;
    width: 30px;
    height: 30px;
    border-radius: 50%;
    background: var(--primary-soft);
    color: var(--primary);
}

.user-name-link { font-size: 14px; font-weight: 500; }

.btn-logout-small {
    font-size: 13px;
    color: var(--ink-3);
    padding: 6px 10px;
    border-radius: 8px;
}

.btn-logout-small:hover { color: var(--primary); }

.btn-login {
    color: var(--primary);
    font-weight: 500;
    padding: 8px 16px;
    border-radius: 8px;
}

.btn-login:hover { background: var(--primary-soft); }

.btn-register {
    background: var(--primary);
    color: #fff !important;
    font-weight: 500;
    padding: 8px 18px;
    border-radius: 8px;
    transition: background 0.2s, transform 0.2s;
}

.btn-register:hover { background: var(--primary-dark); transform: translateY(-1px); }

/* ========== Hero ========== */
.hero {
    background: linear-gradient(180deg, var(--bg-soft) 0%, var(--bg) 100%);
    border-bottom: 1px solid var(--line);
    overflow: hidden;
}

.hero-container {
    max-width: var(--maxw);
    margin: 0 auto;
    padding: 84px 24px 72px;
    display: flex;
    align-items: center;
    gap: 64px;
}

.hero-content { flex: 1.15; }

.hero-badge {
    display: inline-flex;
    align-items: center;
    gap: 8px;
    font-size: 13.5px;
    color: var(--accent);
    background: var(--accent-soft);
    padding: 6px 14px;
    border-radius: 999px;
    font-weight: 500;
    margin-bottom: 24px;
}

.badge-dot {
    width: 6px;
    height: 6px;
    border-radius: 50%;
    background: var(--accent);
}

.hero-title {
    font-size: 46px;
    font-weight: 800;
    line-height: 1.25;
    letter-spacing: -0.5px;
    margin-bottom: 20px;
}

.hero-highlight {
    color: var(--primary);
}

.hero-subtitle {
    font-size: 17px;
    color: var(--ink-2);
    max-width: 520px;
    margin-bottom: 34px;
}

.hero-actions { display: flex; gap: 14px; }

.btn-primary {
    display: inline-block;
    background: var(--primary);
    color: #fff !important;
    font-size: 15.5px;
    font-weight: 600;
    padding: 13px 30px;
    border-radius: 10px;
    transition: background 0.2s, transform 0.2s, box-shadow 0.2s;
}

.btn-primary:hover {
    background: var(--primary-dark);
    transform: translateY(-2px);
    box-shadow: 0 10px 24px rgba(37, 99, 235, 0.28);
}

.btn-secondary {
    display: inline-block;
    color: var(--ink);
    font-size: 15.5px;
    font-weight: 600;
    padding: 13px 30px;
    border-radius: 10px;
    border: 1.5px solid var(--line);
    background: var(--bg);
    transition: border-color 0.2s, color 0.2s;
}

.btn-secondary:hover {
    border-color: var(--primary);
    color: var(--primary);
}

/* Hero 视觉 - 简约票据卡片 */
.hero-visual {
    flex: 1;
    display: flex;
    justify-content: center;
    align-items: center;
}

.visual-stack {
    position: relative;
    width: 320px;
    height: 340px;
}

.v-card {
    position: absolute;
    border-radius: var(--radius);
    background: var(--bg);
    border: 1px solid var(--line);
    box-shadow: var(--shadow);
    padding: 22px;
    transition: transform 0.3s ease;
}

.v-card-back {
    width: 220px;
    height: 150px;
    top: 12px;
    left: 14px;
    transform: rotate(-8deg);
    opacity: 0.7;
}

.v-card-mid {
    width: 240px;
    height: 190px;
    top: 72px;
    right: 0;
    transform: rotate(4deg);
}

.v-card-front {
    width: 230px;
    height: 150px;
    bottom: 0;
    left: 40px;
    transform: rotate(-3deg);
    box-shadow: var(--shadow-lg);
}

.v-card-head {
    display: flex;
    align-items: center;
    gap: 8px;
    margin-bottom: 12px;
}

.v-seal {
    display: flex;
    align-items: center;
    justify-content: center;
    width: 26px;
    height: 26px;
    border-radius: 8px;
    background: var(--accent-soft);
    color: var(--accent);
}

.v-circle {
    width: 12px;
    height: 12px;
    border-radius: 50%;
    background: var(--primary);
}

.v-card-title {
    font-size: 13px;
    font-weight: 600;
    color: var(--ink-2);
}

.v-amount {
    font-size: 26px;
    font-weight: 800;
    color: var(--ink);
    margin-bottom: 12px;
    letter-spacing: -0.5px;
}

.v-amount.small { font-size: 20px; }

.v-line {
    height: 8px;
    border-radius: 4px;
    background: var(--bg-soft);
    border: 1px solid var(--line);
    margin-bottom: 8px;
}

.v-line.w60 { width: 60%; }
.v-line.w80 { width: 80%; }
.v-line.w90 { width: 90%; }
.v-line.w70 { width: 70%; }
.v-line.w55 { width: 55%; }
.v-line.w45 { width: 45%; }

.v-check {
    display: inline-flex;
    align-items: center;
    gap: 5px;
    font-size: 12px;
    font-weight: 500;
    color: var(--accent);
    margin-top: 4px;
}

.v-tag {
    display: inline-block;
    font-size: 11.5px;
    font-weight: 600;
    color: var(--primary);
    background: var(--primary-soft);
    padding: 3px 10px;
    border-radius: 999px;
    margin-top: 2px;
}

/* ========== 统计数字 ========== */
.stats {
    border-bottom: 1px solid var(--line);
    background: var(--bg);
}

.stats-container {
    max-width: var(--maxw);
    margin: 0 auto;
    padding: 36px 24px;
    display: grid;
    grid-template-columns: repeat(4, 1fr);
    gap: 24px;
}

.stat-item {
    text-align: center;
    padding: 12px 8px;
}

.stat-number {
    display: block;
    font-size: 38px;
    font-weight: 800;
    color: var(--primary);
    line-height: 1.2;
    letter-spacing: -0.5px;
}

.stat-label {
    display: block;
    font-size: 14px;
    color: var(--ink-2);
    margin-top: 6px;
}

/* ========== 通用区块 ========== */
.section-container {
    max-width: var(--maxw);
    margin: 0 auto;
    padding: 88px 24px;
}

.section-header {
    text-align: center;
    margin-bottom: 56px;
}

.section-tag {
    display: inline-block;
    font-size: 13px;
    font-weight: 600;
    color: var(--primary);
    background: var(--primary-soft);
    padding: 5px 14px;
    border-radius: 999px;
    letter-spacing: 1px;
    margin-bottom: 16px;
}

.section-title {
    font-size: 32px;
    font-weight: 800;
    line-height: 1.35;
    letter-spacing: -0.3px;
    margin-bottom: 14px;
}

.section-subtitle {
    font-size: 16px;
    color: var(--ink-2);
}

/* ========== 业务模块 ========== */
.services { background: var(--bg); }

.services-grid {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 22px;
}

.service-card {
    background: var(--bg);
    border: 1px solid var(--line);
    border-radius: var(--radius);
    padding: 32px 28px;
    transition: transform 0.25s ease, box-shadow 0.25s ease, border-color 0.25s ease;
}

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

.service-icon {
    display: flex;
    align-items: center;
    justify-content: center;
    width: 52px;
    height: 52px;
    border-radius: 12px;
    background: var(--primary-soft);
    color: var(--primary);
    margin-bottom: 20px;
    transition: background 0.25s, color 0.25s;
}

.service-card:hover .service-icon {
    background: var(--primary);
    color: #fff;
}

.service-card h3 {
    font-size: 18px;
    font-weight: 700;
    margin-bottom: 10px;
}

.service-card p {
    font-size: 14.5px;
    color: var(--ink-2);
    line-height: 1.7;
}

/* ========== 服务场景 ========== */
.solutions { background: var(--bg-soft); border-top: 1px solid var(--line); border-bottom: 1px solid var(--line); }

.solutions-grid {
    display: grid;
    grid-template-columns: repeat(4, 1fr);
    gap: 20px;
}

.solution-card {
    background: var(--bg);
    border: 1px solid var(--line);
    border-radius: var(--radius);
    padding: 30px 24px;
    text-align: center;
    transition: transform 0.25s ease, box-shadow 0.25s ease;
}

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

.solution-icon {
    display: flex;
    align-items: center;
    justify-content: center;
    width: 56px;
    height: 56px;
    border-radius: 50%;
    background: var(--accent-soft);
    color: var(--accent);
    margin: 0 auto 18px;
}

.solution-card h3 {
    font-size: 17px;
    font-weight: 700;
    margin-bottom: 10px;
}

.solution-card p {
    font-size: 13.5px;
    color: var(--ink-2);
    line-height: 1.7;
}

/* ========== 关于我们 ========== */
.about { background: var(--bg); }

.about-content {
    display: flex;
    align-items: center;
    gap: 72px;
}

.about-text { flex: 1.2; }

.about-text .section-tag { margin-bottom: 16px; }

.about-description {
    font-size: 15.5px;
    color: var(--ink-2);
    line-height: 1.9;
    margin: 20px 0 28px;
    max-width: 560px;
}

.about-features {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 14px 24px;
}

.about-feature {
    display: flex;
    align-items: center;
    gap: 10px;
    font-size: 14.5px;
    color: var(--ink);
}

.feature-icon {
    display: flex;
    align-items: center;
    justify-content: center;
    width: 22px;
    height: 22px;
    border-radius: 50%;
    background: var(--accent-soft);
    color: var(--accent);
    flex-shrink: 0;
}

.about-visual { flex: 1; }

.about-card {
    background: var(--bg-soft);
    border: 1px solid var(--line);
    border-radius: var(--radius);
    padding: 34px 30px;
    display: flex;
    flex-direction: column;
    gap: 26px;
}

.about-card-content { display: flex; align-items: flex-start; gap: 14px; }

.about-card-icon {
    display: flex;
    align-items: center;
    justify-content: center;
    width: 40px;
    height: 40px;
    border-radius: 10px;
    background: var(--primary-soft);
    color: var(--primary);
    flex-shrink: 0;
}

.about-card-content h4 {
    font-size: 15.5px;
    font-weight: 700;
    margin-bottom: 3px;
}

.about-card-content p {
    font-size: 13.5px;
    color: var(--ink-2);
}

/* ========== 联系我们 ========== */
.contact { background: var(--bg-soft); border-top: 1px solid var(--line); }

.contact-content {
    display: flex;
    gap: 72px;
    align-items: flex-start;
}

.contact-text { flex: 1.1; }

.contact-text .section-tag { margin-bottom: 16px; }

.contact-description {
    font-size: 15.5px;
    color: var(--ink-2);
    margin: 16px 0 28px;
}

.contact-info { display: flex; flex-direction: column; gap: 16px; }

.contact-item {
    display: flex;
    align-items: center;
    gap: 12px;
    font-size: 15px;
    color: var(--ink);
}

.contact-icon {
    display: flex;
    align-items: center;
    justify-content: center;
    width: 38px;
    height: 38px;
    border-radius: 10px;
    background: var(--primary-soft);
    color: var(--primary);
    flex-shrink: 0;
}

.contact-form {
    flex: 1;
    background: var(--bg);
    border: 1px solid var(--line);
    border-radius: var(--radius);
    padding: 32px;
    box-shadow: var(--shadow);
}

.contact-form form { display: flex; flex-direction: column; gap: 14px; }

.contact-form input,
.contact-form textarea {
    width: 100%;
    padding: 13px 16px;
    border: 1.5px solid var(--line);
    border-radius: 10px;
    font-size: 14.5px;
    font-family: inherit;
    color: var(--ink);
    background: var(--bg);
    transition: border-color 0.2s, box-shadow 0.2s;
    outline: none;
}

.contact-form input:focus,
.contact-form textarea:focus {
    border-color: var(--primary);
    box-shadow: 0 0 0 3px rgba(37, 99, 235, 0.12);
}

.contact-form textarea { resize: vertical; }

.contact-form button {
    border: none;
    cursor: pointer;
    margin-top: 4px;
}

/* ========== 页脚 ========== */
.footer {
    background: var(--bg);
    border-top: 1px solid var(--line);
}

.footer-container {
    max-width: var(--maxw);
    margin: 0 auto;
    padding: 56px 24px 32px;
    display: flex;
    justify-content: space-between;
    gap: 48px;
}

.footer-brand .nav-brand { margin-bottom: 12px; }

.footer-tagline {
    font-size: 13.5px;
    color: var(--ink-3);
}

.footer-links {
    display: flex;
    gap: 72px;
}

.footer-column {
    display: flex;
    flex-direction: column;
    gap: 10px;
}

.footer-column h4 {
    font-size: 14px;
    font-weight: 700;
    color: var(--ink);
    margin-bottom: 6px;
}

.footer-column a {
    font-size: 13.5px;
    color: var(--ink-2);
    transition: color 0.2s;
}

.footer-column a:hover { color: var(--primary); }

.footer-bottom {
    border-top: 1px solid var(--line);
    padding: 18px 24px;
    text-align: center;
    display: flex;
    justify-content: center;
    gap: 20px;
    flex-wrap: wrap;
    font-size: 12.5px;
    color: var(--ink-3);
}

/* ========== 响应式 ========== */
@media (max-width: 1024px) {
    .hero-container { flex-direction: column; gap: 48px; text-align: center; }
    .hero-content { max-width: 640px; }
    .hero-subtitle { margin-left: auto; margin-right: auto; }
    .hero-actions { justify-content: center; }
    .services-grid { grid-template-columns: repeat(2, 1fr); }
    .solutions-grid { grid-template-columns: repeat(2, 1fr); }
    .about-content { flex-direction: column; gap: 40px; }
    .about-text { max-width: 640px; }
    .contact-content { flex-direction: column; gap: 40px; }
    .contact-form { width: 100%; }
    .visual-stack { transform: scale(0.85); }
}

@media (max-width: 640px) {
    .nav-menu > a { padding: 6px 8px; font-size: 13.5px; }
    .nav-divider { display: none; }
    .brand-name { font-size: 17px; }
    .hero-container { padding: 56px 20px 48px; }
    .hero-title { font-size: 32px; }
    .stats-container { grid-template-columns: repeat(2, 1fr); gap: 16px; }
    .services-grid { grid-template-columns: 1fr; }
    .solutions-grid { grid-template-columns: 1fr; }
    .section-container { padding: 64px 20px; }
    .section-title { font-size: 26px; }
    .footer-container { flex-direction: column; gap: 32px; }
    .footer-links { gap: 40px; flex-wrap: wrap; }
}