/* ===================================
   钉钉品牌网站 - 样式表
   Brand Colors: #007FFF (Primary)
   =================================== */

/* ---------- CSS Variables ---------- */
:root {
    --brand-blue: #007FFF;
    --brand-blue-dark: #0056CC;
    --brand-blue-deep: #003D99;
    --brand-blue-light: #3399FF;
    --brand-blue-pale: #E6F2FF;
    --brand-blue-bg: #F0F7FF;

    --text-primary: #1A1A2E;
    --text-secondary: #4A4A68;
    --text-tertiary: #8E8EA0;
    --text-white: #FFFFFF;

    --bg-white: #FFFFFF;
    --bg-light: #F8FAFC;
    --bg-gray: #F1F5F9;
    --bg-card: #FFFFFF;

    --border-light: #E2E8F0;
    --border-lighter: #F0F2F5;

    --shadow-sm: 0 1px 3px rgba(0, 0, 0, 0.06);
    --shadow-md: 0 4px 16px rgba(0, 0, 0, 0.08);
    --shadow-lg: 0 12px 40px rgba(0, 0, 0, 0.12);
    --shadow-brand: 0 8px 24px rgba(0, 127, 255, 0.25);

    --radius-sm: 8px;
    --radius-md: 12px;
    --radius-lg: 20px;
    --radius-xl: 28px;

    --max-width: 1200px;
    --header-height: 72px;

    --transition: 0.25s cubic-bezier(0.4, 0, 0.2, 1);
}

/* ---------- Reset & Base ---------- */
*,
*::before,
*::after {
    box-sizing: border-box;
    margin: 0;
    padding: 0;
}

html {
    scroll-behavior: smooth;
    -webkit-font-smoothing: antialiased;
    -moz-osx-font-smoothing: grayscale;
}

body {
    font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", "PingFang SC", "Hiragino Sans GB", "Microsoft YaHei", "Helvetica Neue", Arial, sans-serif;
    font-size: 16px;
    line-height: 1.6;
    color: var(--text-primary);
    background: var(--bg-white);
    overflow-x: hidden;
}

a {
    text-decoration: none;
    color: inherit;
}

ul {
    list-style: none;
}

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

/* ---------- Header / Navigation ---------- */
.header {
    position: sticky;
    top: 0;
    z-index: 100;
    background: rgba(255, 255, 255, 0.92);
    backdrop-filter: blur(20px);
    -webkit-backdrop-filter: blur(20px);
    border-bottom: 1px solid var(--border-light);
    height: var(--header-height);
}

.nav-container {
    max-width: var(--max-width);
    margin: 0 auto;
    padding: 0 24px;
    height: 100%;
    display: flex;
    align-items: center;
    justify-content: space-between;
}

.logo-link {
    display: flex;
    align-items: center;
    gap: 10px;
    font-size: 22px;
    font-weight: 700;
    color: var(--text-primary);
    letter-spacing: -0.5px;
    transition: var(--transition);
}
.logo-link:hover {
    opacity: 0.85;
}
.logo-icon {
    flex-shrink: 0;
}
.logo-text {
    line-height: 1;
}

.nav-links {
    display: flex;
    align-items: center;
    gap: 4px;
}

.nav-link {
    padding: 8px 16px;
    font-size: 15px;
    font-weight: 500;
    color: var(--text-secondary);
    border-radius: var(--radius-sm);
    transition: var(--transition);
    white-space: nowrap;
}
.nav-link:hover {
    color: var(--brand-blue);
    background: var(--brand-blue-pale);
}
.nav-link.active {
    color: var(--brand-blue);
    font-weight: 600;
}

.nav-cta {
    background: var(--brand-blue);
    color: var(--text-white) !important;
    font-weight: 600;
    padding: 10px 22px;
    border-radius: 24px;
    margin-left: 8px;
    transition: var(--transition);
}
.nav-cta:hover {
    background: var(--brand-blue-dark);
    transform: translateY(-1px);
    box-shadow: var(--shadow-brand);
}

/* ---------- Buttons ---------- */
.btn {
    display: inline-flex;
    align-items: center;
    gap: 8px;
    padding: 14px 32px;
    font-size: 16px;
    font-weight: 600;
    border-radius: 28px;
    cursor: pointer;
    transition: var(--transition);
    border: none;
    white-space: nowrap;
}

.btn-primary {
    background: var(--brand-blue);
    color: var(--text-white);
    box-shadow: 0 4px 16px rgba(0, 127, 255, 0.3);
}
.btn-primary:hover {
    background: var(--brand-blue-dark);
    transform: translateY(-2px);
    box-shadow: 0 8px 24px rgba(0, 127, 255, 0.4);
}

.btn-outline {
    background: transparent;
    color: var(--brand-blue);
    border: 2px solid var(--brand-blue);
}
.btn-outline:hover {
    background: var(--brand-blue-pale);
    transform: translateY(-2px);
}

.btn-white {
    background: var(--text-white);
    color: var(--brand-blue);
    box-shadow: 0 4px 16px rgba(0, 0, 0, 0.15);
}
.btn-white:hover {
    transform: translateY(-2px);
    box-shadow: 0 8px 24px rgba(0, 0, 0, 0.25);
}

.btn-outline-white {
    background: transparent;
    color: var(--text-white);
    border: 2px solid rgba(255, 255, 255, 0.5);
}
.btn-outline-white:hover {
    background: rgba(255, 255, 255, 0.15);
    border-color: var(--text-white);
    transform: translateY(-2px);
}

.btn-download {
    width: 100%;
    justify-content: center;
    padding: 16px 24px;
    margin-bottom: 12px;
}

.btn-outline-sm {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    gap: 6px;
    padding: 10px 20px;
    font-size: 14px;
    font-weight: 500;
    border: 1.5px solid var(--border-light);
    border-radius: 24px;
    color: var(--text-secondary);
    width: 100%;
    transition: var(--transition);
}
.btn-outline-sm:hover {
    border-color: var(--brand-blue);
    color: var(--brand-blue);
    background: var(--brand-blue-pale);
}

/* ---------- Hero Section ---------- */
.hero {
    max-width: var(--max-width);
    margin: 0 auto;
    padding: 80px 24px 100px;
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 60px;
    align-items: center;
    min-height: calc(100vh - var(--header-height));
}

.hero-content {
    display: flex;
    flex-direction: column;
    gap: 24px;
}

.hero-badge {
    display: inline-flex;
    align-items: center;
    gap: 8px;
    background: var(--brand-blue-pale);
    color: var(--brand-blue);
    font-size: 14px;
    font-weight: 600;
    padding: 8px 18px;
    border-radius: 20px;
    width: fit-content;
}

.hero h1 {
    font-size: clamp(36px, 5vw, 56px);
    font-weight: 800;
    line-height: 1.2;
    letter-spacing: -1.5px;
    color: var(--text-primary);
    margin: 0;
}

.hero-desc {
    font-size: 18px;
    line-height: 1.8;
    color: var(--text-secondary);
    max-width: 520px;
}

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

.hero-stats {
    display: flex;
    align-items: center;
    gap: 28px;
    margin-top: 16px;
    padding: 24px 0;
    border-top: 1px solid var(--border-light);
}

.stat-item {
    display: flex;
    flex-direction: column;
    gap: 2px;
}
.stat-number {
    font-size: 28px;
    font-weight: 800;
    color: var(--brand-blue);
    letter-spacing: -0.5px;
}
.stat-label {
    font-size: 14px;
    color: var(--text-tertiary);
}

.stat-divider {
    width: 1px;
    height: 40px;
    background: var(--border-light);
}

/* Hero Visual */
.hero-visual {
    position: relative;
    display: flex;
    align-items: center;
    justify-content: center;
    height: 480px;
}

.hero-graphic {
    position: relative;
    width: 100%;
    height: 100%;
}

.hero-circle {
    position: absolute;
    top: 50%;
    left: 50%;
    transform: translate(-50%, -50%);
    width: 320px;
    height: 320px;
    background: radial-gradient(circle at 40% 40%, var(--brand-blue-light), var(--brand-blue));
    border-radius: 50%;
    box-shadow: 0 20px 60px rgba(0, 127, 255, 0.35);
    animation: float 6s ease-in-out infinite;
}

@keyframes float {
    0%, 100% { transform: translate(-50%, -50%) translateY(0); }
    50% { transform: translate(-50%, -50%) translateY(-16px); }
}

.floating-card {
    position: absolute;
    background: var(--bg-white);
    border-radius: var(--radius-md);
    box-shadow: var(--shadow-lg);
    padding: 16px 20px;
    z-index: 2;
    animation: floatCard 5s ease-in-out infinite;
}

.card-chat {
    top: 20px;
    right: 0;
    width: 230px;
    animation-delay: 0s;
}

.card-meeting {
    bottom: 40px;
    left: 0;
    display: flex;
    align-items: center;
    gap: 12px;
    font-size: 14px;
    font-weight: 600;
    color: var(--brand-blue);
    animation-delay: 1.5s;
}

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

.card-header {
    display: flex;
    align-items: center;
    gap: 8px;
    font-size: 13px;
    font-weight: 600;
    color: var(--text-secondary);
    margin-bottom: 12px;
    padding-bottom: 10px;
    border-bottom: 1px solid var(--border-lighter);
}
.card-dot {
    width: 8px;
    height: 8px;
    background: #22C55E;
    border-radius: 50%;
}

.card-msgs {
    display: flex;
    flex-direction: column;
    gap: 8px;
}
.msg {
    font-size: 12px;
    padding: 8px 12px;
    border-radius: 10px;
    line-height: 1.5;
}
.msg.received {
    background: var(--bg-gray);
    color: var(--text-secondary);
    align-self: flex-start;
    border-bottom-left-radius: 2px;
}
.msg.sent {
    background: var(--brand-blue-pale);
    color: var(--brand-blue);
    align-self: flex-end;
    border-bottom-right-radius: 2px;
}

.meeting-icon {
    display: flex;
    align-items: center;
    justify-content: center;
    width: 44px;
    height: 44px;
    background: var(--brand-blue-pale);
    border-radius: 12px;
    color: var(--brand-blue);
}

/* ---------- Section Common ---------- */
.section-header {
    text-align: center;
    margin-bottom: 56px;
}
.section-header h2 {
    font-size: clamp(28px, 4vw, 40px);
    font-weight: 800;
    letter-spacing: -0.5px;
    color: var(--text-primary);
    margin-bottom: 12px;
}
.section-subtitle {
    font-size: 17px;
    color: var(--text-tertiary);
    max-width: 600px;
    margin: 0 auto;
}

/* ---------- Features Section ---------- */
.features {
    padding: 100px 24px;
    background: var(--bg-light);
}

.features-grid {
    max-width: var(--max-width);
    margin: 0 auto;
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 24px;
}

.feature-card {
    background: var(--bg-white);
    border-radius: var(--radius-lg);
    padding: 32px 28px;
    transition: var(--transition);
    border: 1px solid transparent;
}
.feature-card:hover {
    transform: translateY(-4px);
    box-shadow: var(--shadow-md);
    border-color: var(--brand-blue-pale);
}

.feature-icon {
    width: 56px;
    height: 56px;
    border-radius: var(--radius-md);
    display: flex;
    align-items: center;
    justify-content: center;
    margin-bottom: 20px;
}

.feature-card h3 {
    font-size: 18px;
    font-weight: 700;
    margin-bottom: 10px;
    color: var(--text-primary);
}

.feature-card p {
    font-size: 14px;
    line-height: 1.7;
    color: var(--text-tertiary);
}

/* ---------- Solutions Section ---------- */
.solutions {
    padding: 100px 24px;
}

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

.solution-card {
    text-align: center;
    padding: 36px 20px;
    border-radius: var(--radius-lg);
    background: var(--bg-white);
    border: 1px solid var(--border-light);
    transition: var(--transition);
}
.solution-card:hover {
    border-color: var(--brand-blue);
    box-shadow: var(--shadow-md);
    transform: translateY(-2px);
}

.solution-img {
    margin-bottom: 20px;
    display: flex;
    justify-content: center;
}

.solution-card h3 {
    font-size: 17px;
    font-weight: 700;
    margin-bottom: 8px;
}

.solution-card p {
    font-size: 14px;
    color: var(--text-tertiary);
}

/* ---------- About Section ---------- */
.about {
    padding: 100px 24px;
    background: var(--bg-light);
}

.about-wrapper {
    max-width: var(--max-width);
    margin: 0 auto;
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 60px;
    align-items: center;
}

.about-text h2 {
    font-size: clamp(28px, 4vw, 38px);
    font-weight: 800;
    margin-bottom: 32px;
    letter-spacing: -0.5px;
}

.about-list {
    display: flex;
    flex-direction: column;
    gap: 20px;
}

.about-list li {
    display: flex;
    gap: 14px;
    align-items: flex-start;
    font-size: 15px;
    line-height: 1.8;
    color: var(--text-secondary);
}

.about-list li svg {
    flex-shrink: 0;
    margin-top: 3px;
}

.about-list li strong {
    color: var(--text-primary);
}

.about-visual {
    display: flex;
    flex-direction: column;
    gap: 20px;
}

.about-card {
    background: var(--bg-white);
    border-radius: var(--radius-lg);
    padding: 28px 32px;
    border: 1px solid var(--border-light);
    transition: var(--transition);
}
.about-card:hover {
    box-shadow: var(--shadow-md);
    border-color: var(--brand-blue-pale);
}

.about-card-icon {
    font-size: 24px;
    margin-bottom: 8px;
}

.about-card-title {
    font-size: 13px;
    color: var(--text-tertiary);
    text-transform: uppercase;
    letter-spacing: 1px;
    margin-bottom: 8px;
}

.about-card-value {
    font-size: 20px;
    font-weight: 700;
    line-height: 1.6;
    color: var(--text-primary);
}
.about-card-value .highlight {
    color: var(--brand-blue);
    font-weight: 800;
}

/* ---------- CTA Section ---------- */
.cta {
    padding: 100px 24px;
    background: linear-gradient(135deg, var(--brand-blue), var(--brand-blue-dark));
    text-align: center;
}

.cta-content {
    max-width: 600px;
    margin: 0 auto;
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: 16px;
}

.cta h2 {
    font-size: clamp(28px, 4vw, 40px);
    font-weight: 800;
    color: var(--text-white);
    letter-spacing: -0.5px;
}

.cta p {
    font-size: 18px;
    color: rgba(255, 255, 255, 0.85);
    margin-bottom: 8px;
}

.cta-actions {
    display: flex;
    gap: 16px;
    flex-wrap: wrap;
    justify-content: center;
}

/* ---------- Footer ---------- */
.footer {
    background: #0F172A;
    padding: 60px 24px 24px;
    color: rgba(255, 255, 255, 0.7);
}

.footer-container {
    max-width: var(--max-width);
    margin: 0 auto;
    display: grid;
    grid-template-columns: 1.5fr 2fr;
    gap: 48px;
    padding-bottom: 40px;
    border-bottom: 1px solid rgba(255, 255, 255, 0.1);
}

.footer-brand p {
    margin-top: 12px;
    font-size: 14px;
    line-height: 1.8;
    color: rgba(255, 255, 255, 0.5);
}

.footer-logo {
    display: flex;
    align-items: center;
    gap: 8px;
    font-size: 20px;
    font-weight: 700;
    color: var(--text-white);
}

.footer-links {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 24px;
}

.footer-col h4 {
    font-size: 15px;
    font-weight: 600;
    color: var(--text-white);
    margin-bottom: 16px;
}

.footer-col a {
    display: block;
    font-size: 14px;
    color: rgba(255, 255, 255, 0.55);
    padding: 4px 0;
    transition: var(--transition);
}
.footer-col a:hover {
    color: var(--brand-blue-light);
}

.footer-bottom {
    max-width: var(--max-width);
    margin: 0 auto;
    padding-top: 20px;
    font-size: 13px;
    color: rgba(255, 255, 255, 0.35);
    text-align: center;
}

/* ===================================
   下载页专属样式
   =================================== */

/* Download Hero */
.download-hero {
    background: linear-gradient(135deg, var(--brand-blue-bg), var(--brand-blue-pale));
    padding: 80px 24px;
    text-align: center;
}

.download-hero-content {
    max-width: 700px;
    margin: 0 auto;
}

.download-hero h1 {
    font-size: clamp(32px, 5vw, 48px);
    font-weight: 800;
    letter-spacing: -1px;
    margin-bottom: 16px;
}

.download-hero-desc {
    font-size: 18px;
    color: var(--text-secondary);
    line-height: 1.8;
    margin-bottom: 24px;
}

.version-badge {
    display: inline-flex;
    align-items: center;
    gap: 8px;
    background: var(--bg-white);
    color: var(--text-secondary);
    font-size: 14px;
    padding: 10px 22px;
    border-radius: 24px;
    box-shadow: var(--shadow-sm);
}

/* Download Grid */
.download-main {
    padding: 80px 24px 100px;
}

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

.download-card {
    background: var(--bg-white);
    border-radius: var(--radius-lg);
    padding: 36px 24px;
    text-align: center;
    border: 2px solid var(--border-light);
    transition: var(--transition);
    position: relative;
    display: flex;
    flex-direction: column;
    align-items: center;
}
.download-card:hover {
    border-color: var(--brand-blue-pale);
    box-shadow: var(--shadow-lg);
    transform: translateY(-4px);
}

.download-card.featured {
    border-color: var(--brand-blue);
    box-shadow: var(--shadow-brand);
}

.download-card-badge {
    position: absolute;
    top: -12px;
    left: 50%;
    transform: translateX(-50%);
    background: var(--brand-blue);
    color: var(--text-white);
    font-size: 12px;
    font-weight: 700;
    padding: 4px 16px;
    border-radius: 12px;
    white-space: nowrap;
}

.download-card-icon {
    margin-bottom: 20px;
    display: flex;
    justify-content: center;
    color: var(--brand-blue);
}

.download-card h3 {
    font-size: 18px;
    font-weight: 700;
    margin-bottom: 8px;
}

.download-card-desc {
    font-size: 14px;
    color: var(--text-tertiary);
    margin-bottom: 4px;
}

.download-card-info {
    font-size: 13px;
    color: var(--brand-blue);
    font-weight: 500;
    margin-bottom: 20px;
    padding: 6px 14px;
    background: var(--brand-blue-pale);
    border-radius: 20px;
}

.download-card-note {
    font-size: 12px;
    color: var(--text-tertiary);
    margin-top: 8px;
}

/* Requirements Table */
.requirements {
    padding: 80px 24px 100px;
    background: var(--bg-light);
}

.req-table-wrapper {
    max-width: 900px;
    margin: 0 auto;
    overflow-x: auto;
}

.req-table {
    width: 100%;
    border-collapse: collapse;
    background: var(--bg-white);
    border-radius: var(--radius-lg);
    overflow: hidden;
    box-shadow: var(--shadow-sm);
}

.req-table thead {
    background: var(--brand-blue);
    color: var(--text-white);
}

.req-table th {
    padding: 16px 24px;
    font-size: 14px;
    font-weight: 600;
    text-align: left;
    white-space: nowrap;
}

.req-table td {
    padding: 16px 24px;
    font-size: 14px;
    color: var(--text-secondary);
    border-bottom: 1px solid var(--border-lighter);
}

.req-table tbody tr:last-child td {
    border-bottom: none;
}

.req-table tbody tr:hover {
    background: var(--brand-blue-bg);
}

/* More Downloads */
.more-downloads {
    padding: 80px 24px 100px;
}

.more-grid {
    max-width: var(--max-width);
    margin: 0 auto;
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 24px;
}

.more-card {
    background: var(--bg-white);
    border: 1px solid var(--border-light);
    border-radius: var(--radius-lg);
    padding: 28px;
    transition: var(--transition);
}
.more-card:hover {
    box-shadow: var(--shadow-md);
    border-color: var(--brand-blue-pale);
}

.more-card h4 {
    font-size: 17px;
    font-weight: 700;
    margin-bottom: 8px;
}

.more-card p {
    font-size: 14px;
    color: var(--text-tertiary);
    line-height: 1.7;
    margin-bottom: 12px;
}

.more-link {
    font-size: 14px;
    font-weight: 600;
    color: var(--brand-blue);
    transition: var(--transition);
}
.more-link:hover {
    color: var(--brand-blue-dark);
    gap: 4px;
}

/* ---------- Responsive ---------- */
@media (max-width: 1024px) {
    .hero {
        grid-template-columns: 1fr;
        text-align: center;
        gap: 40px;
        padding: 60px 24px 80px;
        min-height: auto;
    }
    .hero-content {
        align-items: center;
    }
    .hero-desc {
        max-width: 100%;
    }
    .hero-actions {
        justify-content: center;
    }
    .hero-stats {
        justify-content: center;
    }
    .hero-visual {
        height: 360px;
    }
    .hero-circle {
        width: 240px;
        height: 240px;
    }
    .card-chat {
        right: 10%;
    }
    .card-meeting {
        left: 10%;
    }

    .features-grid {
        grid-template-columns: repeat(2, 1fr);
    }

    .solutions-grid {
        grid-template-columns: repeat(2, 1fr);
    }

    .about-wrapper {
        grid-template-columns: 1fr;
        gap: 40px;
    }

    .download-grid {
        grid-template-columns: repeat(2, 1fr);
    }

    .more-grid {
        grid-template-columns: repeat(2, 1fr);
    }
}

@media (max-width: 768px) {
    :root {
        --header-height: 64px;
    }

    .nav-links {
        display: none;
    }

    .hero {
        padding: 48px 20px 64px;
    }
    .hero h1 {
        font-size: 30px;
    }
    .hero-desc {
        font-size: 16px;
    }
    .hero-stats {
        gap: 16px;
        flex-wrap: wrap;
    }
    .stat-number {
        font-size: 22px;
    }
    .stat-divider {
        display: none;
    }

    .hero-visual {
        height: 280px;
    }
    .hero-circle {
        width: 180px;
        height: 180px;
    }
    .floating-card {
        display: none;
    }

    .features {
        padding: 64px 20px;
    }
    .features-grid {
        grid-template-columns: 1fr;
    }

    .solutions {
        padding: 64px 20px;
    }
    .solutions-grid {
        grid-template-columns: repeat(2, 1fr);
    }

    .about {
        padding: 64px 20px;
    }

    .cta {
        padding: 64px 20px;
    }
    .cta h2 {
        font-size: 28px;
    }

    .footer-container {
        grid-template-columns: 1fr;
        gap: 32px;
    }
    .footer-links {
        grid-template-columns: repeat(2, 1fr);
    }

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

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

    .section-header {
        margin-bottom: 40px;
    }
    .section-header h2 {
        font-size: 28px;
    }
}

@media (max-width: 480px) {
    .hero-actions {
        flex-direction: column;
        width: 100%;
    }
    .hero-actions .btn {
        width: 100%;
        justify-content: center;
    }

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

    .download-hero h1 {
        font-size: 28px;
    }

    .req-table th,
    .req-table td {
        padding: 12px 14px;
        font-size: 12px;
    }
}