/* ===================================
   Milo Landing Page Styles
   极简现代风格设计
   =================================== */

/* CSS Variables */
:root {
    --color-primary: #3b82f6;
    --color-primary-dark: #2563eb;
    --color-primary-light: #60a5fa;
    --color-text: #1f2937;
    --color-text-muted: #6b7280;
    --color-text-light: #9ca3af;
    --color-bg: #ffffff;
    --color-bg-alt: #f9fafb;
    --color-border: #e5e7eb;
    --color-shadow: rgba(0, 0, 0, 0.1);

    --font-main: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', sans-serif;
    --font-display: 'Outfit', sans-serif;

    --spacing-xs: 0.5rem;
    --spacing-sm: 1rem;
    --spacing-md: 1.5rem;
    --spacing-lg: 2rem;
    --spacing-xl: 3rem;
    --spacing-2xl: 4rem;
    --spacing-3xl: 6rem;

    --transition: all 0.3s cubic-bezier(0.4, 0, 0.2, 1);
    --transition-fast: all 0.15s cubic-bezier(0.4, 0, 0.2, 1);
}

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

html {
    scroll-behavior: smooth;
}

body {
    font-family: var(--font-main);
    color: var(--color-text);
    background-color: var(--color-bg);
    line-height: 1.6;
    -webkit-font-smoothing: antialiased;
    -moz-osx-font-smoothing: grayscale;
    overflow-x: hidden;
}

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

ul {
    list-style: none;
}

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

/* Typography */
h1, h2, h3, h4, h5, h6 {
    font-family: var(--font-display);
    font-weight: 600;
    line-height: 1.2;
    color: var(--color-text);
}

p {
    color: var(--color-text-muted);
    line-height: 1.7;
}

.highlight {
    color: var(--color-primary);
    font-weight: 500;
}

/* ===================================
   Navigation
   =================================== */
.nav {
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    z-index: 1000;
    background: rgba(255, 255, 255, 0.8);
    backdrop-filter: blur(12px);
    -webkit-backdrop-filter: blur(12px);
    border-bottom: 1px solid var(--color-border);
}

.nav-container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 1rem 2rem;
    display: flex;
    align-items: center;
    justify-content: space-between;
}

.nav-logo {
    display: flex;
    align-items: center;
    gap: 0.75rem;
    font-family: var(--font-display);
    font-weight: 700;
    font-size: 1.25rem;
    letter-spacing: 0.05em;
}

.logo-img {
    width: 32px;
    height: 32px;
    object-fit: contain;
}

.logo-text {
    color: var(--color-text);
}

.nav-menu {
    display: flex;
    align-items: center;
    gap: 2rem;
}

.nav-link {
    font-size: 0.9375rem;
    font-weight: 500;
    color: var(--color-text-muted);
    transition: var(--transition-fast);
    position: relative;
}

.nav-link::after {
    content: '';
    position: absolute;
    bottom: -4px;
    left: 0;
    width: 0;
    height: 2px;
    background: var(--color-primary);
    transition: width 0.3s ease;
}

.nav-link:hover {
    color: var(--color-primary);
}

.nav-link:hover::after {
    width: 100%;
}

.nav-cta {
    padding: 0.625rem 1.5rem;
    background: var(--color-primary);
    color: white;
    border-radius: 8px;
    font-size: 0.9375rem;
    font-weight: 500;
    transition: var(--transition);
    box-shadow: 0 4px 6px -1px rgba(59, 130, 246, 0.2);
}

.nav-cta:hover {
    background: var(--color-primary-dark);
    transform: translateY(-1px);
    box-shadow: 0 6px 12px -1px rgba(59, 130, 246, 0.3);
}

/* ===================================
   Hero Section
   =================================== */
.hero {
    padding: 8rem 2rem 4rem;
    min-height: 100vh;
    display: flex;
    align-items: center;
    background: linear-gradient(135deg, #f9fafb 0%, #ffffff 100%);
    position: relative;
    overflow: hidden;
}

.hero::before {
    content: '';
    position: absolute;
    top: -50%;
    right: -10%;
    width: 60%;
    height: 200%;
    background: radial-gradient(circle, rgba(59, 130, 246, 0.05) 0%, transparent 70%);
    animation: float 20s ease-in-out infinite;
}

@keyframes float {
    0%, 100% { transform: translate(0, 0); }
    50% { transform: translate(-30px, 30px); }
}

.hero-container {
    max-width: 1200px;
    margin: 0 auto;
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 4rem;
    align-items: center;
    position: relative;
    z-index: 1;
}

.hero-badge {
    display: inline-flex;
    align-items: center;
    gap: 0.5rem;
    padding: 0.5rem 1rem;
    background: rgba(59, 130, 246, 0.1);
    border-radius: 100px;
    font-size: 0.875rem;
    font-weight: 500;
    color: var(--color-primary);
    margin-bottom: 1.5rem;
}

.badge-dot {
    width: 8px;
    height: 8px;
    background: var(--color-primary);
    border-radius: 50%;
    animation: pulse 2s ease-in-out infinite;
}

@keyframes pulse {
    0%, 100% { opacity: 1; }
    50% { opacity: 0.5; }
}

.hero-title {
    margin-bottom: 1.5rem;
}

.title-main {
    display: block;
    font-size: 4rem;
    font-weight: 700;
    background: linear-gradient(135deg, var(--color-primary) 0%, var(--color-primary-dark) 100%);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
    margin-bottom: 0.5rem;
}

.title-sub {
    display: block;
    font-size: 2rem;
    font-weight: 600;
    color: var(--color-text);
}

.hero-description {
    font-size: 1.125rem;
    margin-bottom: 1rem;
    color: var(--color-text-muted);
}

.hero-tagline {
    font-size: 1.25rem;
    font-weight: 500;
    color: var(--color-text);
    margin-bottom: 2rem;
    font-family: var(--font-display);
}

.hero-actions {
    display: flex;
    gap: 1rem;
    flex-wrap: wrap;
}

.btn {
    display: inline-flex;
    align-items: center;
    gap: 0.5rem;
    padding: 0.875rem 1.75rem;
    border-radius: 10px;
    font-size: 1rem;
    font-weight: 500;
    transition: var(--transition);
    cursor: pointer;
    border: none;
}

.btn-primary {
    background: var(--color-primary);
    color: white;
    box-shadow: 0 4px 12px rgba(59, 130, 246, 0.3);
}

.btn-primary:hover {
    background: var(--color-primary-dark);
    transform: translateY(-2px);
    box-shadow: 0 6px 20px rgba(59, 130, 246, 0.4);
}

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

.btn-secondary:hover {
    border-color: var(--color-primary);
    color: var(--color-primary);
    transform: translateY(-2px);
}

.btn-large {
    padding: 1rem 2rem;
    font-size: 1.125rem;
}

/* Hero Card */
.hero-visual {
    position: relative;
}

.hero-card {
    background: white;
    border-radius: 16px;
    box-shadow: 0 20px 60px rgba(0, 0, 0, 0.1);
    overflow: hidden;
    border: 1px solid var(--color-border);
    animation: cardFloat 6s ease-in-out infinite;
}

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

.card-header {
    padding: 1rem 1.5rem;
    background: #f9fafb;
    border-bottom: 1px solid var(--color-border);
    display: flex;
    align-items: center;
    gap: 1rem;
}

.card-dots {
    display: flex;
    gap: 0.375rem;
}

.dot {
    width: 12px;
    height: 12px;
    border-radius: 50%;
}

.dot.red { background: #ef4444; }
.dot.yellow { background: #f59e0b; }
.dot.green { background: #10b981; }

.card-title {
    font-size: 0.875rem;
    font-weight: 500;
    color: var(--color-text-muted);
}

.card-body {
    padding: 1.5rem;
    display: flex;
    flex-direction: column;
    gap: 1rem;
}

.message {
    display: flex;
    gap: 0.75rem;
    max-width: 85%;
}

.message.assistant {
    align-self: flex-start;
}

.message.user {
    align-self: flex-end;
    flex-direction: row-reverse;
}

.message-avatar {
    width: 32px;
    height: 32px;
    border-radius: 8px;
    overflow: hidden;
    flex-shrink: 0;
}

.message-avatar img {
    width: 100%;
    height: 100%;
    object-fit: contain;
}

.message-content {
    background: #f3f4f6;
    padding: 0.75rem 1rem;
    border-radius: 12px;
    font-size: 0.9375rem;
}

.message.user .message-content {
    background: var(--color-primary);
    color: white;
}

/* ===================================
   Value Proposition
   =================================== */
.value-prop {
    padding: var(--spacing-3xl) 2rem;
    background: white;
}

.value-prop-container {
    max-width: 1200px;
    margin: 0 auto;
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 3rem;
}

.value-item {
    text-align: center;
}

.value-icon {
    width: 64px;
    height: 64px;
    margin: 0 auto 1.5rem;
    display: flex;
    align-items: center;
    justify-content: center;
    background: linear-gradient(135deg, rgba(59, 130, 246, 0.1) 0%, rgba(59, 130, 246, 0.05) 100%);
    border-radius: 16px;
    color: var(--color-primary);
}

.value-item h3 {
    font-size: 1.25rem;
    margin-bottom: 1rem;
}

.value-item p {
    font-size: 1rem;
    line-height: 1.8;
}

/* ===================================
   Sections Common
   =================================== */
section {
    position: relative;
}

.section-container {
    max-width: 1200px;
    margin: 0 auto;
    padding: var(--spacing-3xl) 2rem;
}

.section-header {
    text-align: center;
    margin-bottom: var(--spacing-3xl);
}

.section-label {
    display: inline-block;
    padding: 0.5rem 1rem;
    background: rgba(59, 130, 246, 0.1);
    color: var(--color-primary);
    font-size: 0.875rem;
    font-weight: 600;
    border-radius: 100px;
    margin-bottom: 1rem;
    letter-spacing: 0.05em;
}

.section-header h2 {
    font-size: 2.5rem;
    margin-bottom: 1rem;
}

.section-header p {
    font-size: 1.125rem;
    max-width: 600px;
    margin: 0 auto;
}

/* ===================================
   Roles Section
   =================================== */
.roles {
    background: var(--color-bg-alt);
}

.roles-grid {
    display: grid;
    grid-template-columns: repeat(4, 1fr);
    gap: 2rem;
}

.role-card {
    background: white;
    padding: 2rem;
    border-radius: 16px;
    border: 1px solid var(--color-border);
    transition: var(--transition);
}

.role-card:hover {
    transform: translateY(-8px);
    box-shadow: 0 12px 24px rgba(0, 0, 0, 0.1);
    border-color: var(--color-primary);
}

.role-icon {
    font-size: 3rem;
    margin-bottom: 1rem;
}

.role-card h3 {
    font-size: 1.5rem;
    margin-bottom: 0.5rem;
}

.role-tag {
    display: inline-block;
    padding: 0.25rem 0.75rem;
    background: rgba(59, 130, 246, 0.1);
    color: var(--color-primary);
    font-size: 0.75rem;
    font-weight: 600;
    border-radius: 6px;
    margin-bottom: 1rem;
    text-transform: uppercase;
    letter-spacing: 0.05em;
}

.role-card p {
    font-size: 0.9375rem;
    line-height: 1.7;
}

/* ===================================
   Capabilities Section
   =================================== */
.capabilities-grid {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 2rem;
}

.capability-card {
    background: white;
    padding: 2.5rem;
    border-radius: 20px;
    border: 1px solid var(--color-border);
    text-align: center;
    transition: var(--transition);
}

.capability-card:hover {
    transform: translateY(-4px);
    box-shadow: 0 20px 40px rgba(0, 0, 0, 0.08);
}

.capability-icon {
    width: 80px;
    height: 80px;
    margin: 0 auto 1.5rem;
    display: flex;
    align-items: center;
    justify-content: center;
    background: linear-gradient(135deg, rgba(59, 130, 246, 0.1) 0%, rgba(59, 130, 246, 0.05) 100%);
    border-radius: 20px;
    color: var(--color-primary);
}

.capability-card h3 {
    font-size: 1.5rem;
    margin-bottom: 0.5rem;
}

.capability-card h4 {
    font-size: 1.125rem;
    color: var(--color-text-muted);
    margin-bottom: 1.5rem;
    font-weight: 500;
}

.capability-card ul {
    text-align: left;
}

.capability-card li {
    padding: 0.5rem 0;
    font-size: 0.9375rem;
    color: var(--color-text-muted);
    position: relative;
    padding-left: 1.5rem;
}

.capability-card li::before {
    content: '✓';
    position: absolute;
    left: 0;
    color: var(--color-primary);
    font-weight: 600;
}

/* ===================================
   Features Section
   =================================== */
.features {
    background: var(--color-bg-alt);
}

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

.feature-item {
    display: flex;
    gap: 1.5rem;
    padding: 2rem;
    background: white;
    border-radius: 16px;
    border: 1px solid var(--color-border);
    transition: var(--transition);
}

.feature-item:hover {
    transform: translateX(8px);
    box-shadow: 0 8px 24px rgba(0, 0, 0, 0.08);
    border-color: var(--color-primary);
}

.feature-icon {
    width: 56px;
    height: 56px;
    flex-shrink: 0;
    display: flex;
    align-items: center;
    justify-content: center;
    background: linear-gradient(135deg, rgba(59, 130, 246, 0.1) 0%, rgba(59, 130, 246, 0.05) 100%);
    border-radius: 12px;
    color: var(--color-primary);
}

.feature-content h3 {
    font-size: 1.25rem;
    margin-bottom: 0.5rem;
}

.feature-content p {
    font-size: 0.9375rem;
    line-height: 1.7;
}

/* ===================================
   Tech Section
   =================================== */
.tech-grid {
    display: grid;
    grid-template-columns: repeat(4, 1fr);
    gap: 2rem;
}

.tech-card {
    text-align: center;
    padding: 2rem;
    background: var(--color-bg-alt);
    border-radius: 16px;
    transition: var(--transition);
}

.tech-card:hover {
    background: white;
    box-shadow: 0 8px 24px rgba(0, 0, 0, 0.08);
    transform: translateY(-4px);
}

.tech-icon {
    width: 72px;
    height: 72px;
    margin: 0 auto 1.5rem;
    display: flex;
    align-items: center;
    justify-content: center;
    background: white;
    border-radius: 16px;
    color: var(--color-primary);
    border: 1px solid var(--color-border);
}

.tech-card h3 {
    font-size: 1.25rem;
    margin-bottom: 0.75rem;
}

.tech-card p {
    font-size: 0.9375rem;
}

/* ===================================
   CTA Section
   =================================== */
.cta {
    background: linear-gradient(135deg, var(--color-primary) 0%, var(--color-primary-dark) 100%);
    color: white;
}

.cta-container {
    max-width: 800px;
    margin: 0 auto;
    padding: var(--spacing-3xl) 2rem;
    text-align: center;
}

.cta-content h2 {
    font-size: 3rem;
    color: white;
    margin-bottom: 1rem;
}

.cta-content > p {
    font-size: 1.25rem;
    color: rgba(255, 255, 255, 0.9);
    margin-bottom: 2rem;
}

.cta-actions {
    display: flex;
    gap: 1rem;
    justify-content: center;
    flex-wrap: wrap;
    margin-bottom: 1.5rem;
}

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

.cta .btn-primary:hover {
    background: #f9fafb;
    transform: translateY(-2px);
    box-shadow: 0 8px 20px rgba(0, 0, 0, 0.15);
}

.cta .btn-secondary {
    background: transparent;
    color: white;
    border-color: rgba(255, 255, 255, 0.5);
}

.cta .btn-secondary:hover {
    background: rgba(255, 255, 255, 0.1);
    border-color: white;
}

.cta-note {
    font-size: 0.9375rem;
    color: rgba(255, 255, 255, 0.7);
}

/* ===================================
   Footer
   =================================== */
.footer {
    background: #111827;
    color: white;
    padding: 4rem 2rem 2rem;
}

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

.footer-brand {
    display: flex;
    flex-direction: column;
    align-items: center;
    text-align: center;
    margin-bottom: 3rem;
}

.footer-logo {
    display: flex;
    align-items: center;
    gap: 0.75rem;
    font-family: var(--font-display);
    font-size: 1.5rem;
    font-weight: 700;
    margin-bottom: 0.5rem;
}

.footer-logo img {
    width: 40px;
    height: 40px;
}

.footer-brand p {
    color: rgba(255, 255, 255, 0.6);
    font-size: 1rem;
}

.footer-links {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 3rem;
    margin-bottom: 3rem;
    max-width: 800px;
    margin-left: auto;
    margin-right: auto;
}

.footer-section h4 {
    color: white;
    font-size: 1rem;
    margin-bottom: 1rem;
}

.footer-section a {
    display: block;
    color: rgba(255, 255, 255, 0.6);
    font-size: 0.9375rem;
    padding: 0.5rem 0;
    transition: var(--transition-fast);
}

.footer-section a:hover {
    color: white;
    padding-left: 4px;
}

.footer-bottom {
    text-align: center;
    padding-top: 2rem;
    border-top: 1px solid rgba(255, 255, 255, 0.1);
}

.footer-bottom p {
    color: rgba(255, 255, 255, 0.5);
    font-size: 0.875rem;
}

/* ===================================
   Animations
   =================================== */
.fade-in {
    opacity: 0;
    transform: translateY(30px);
    transition: opacity 0.8s ease, transform 0.8s ease;
}

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

/* Staggered animation delays */
.roles-grid .fade-in:nth-child(1) { transition-delay: 0.1s; }
.roles-grid .fade-in:nth-child(2) { transition-delay: 0.2s; }
.roles-grid .fade-in:nth-child(3) { transition-delay: 0.3s; }
.roles-grid .fade-in:nth-child(4) { transition-delay: 0.4s; }

.capabilities-grid .fade-in:nth-child(1) { transition-delay: 0.1s; }
.capabilities-grid .fade-in:nth-child(2) { transition-delay: 0.2s; }
.capabilities-grid .fade-in:nth-child(3) { transition-delay: 0.3s; }

.features-list .fade-in:nth-child(odd) { transition-delay: 0.1s; }
.features-list .fade-in:nth-child(even) { transition-delay: 0.2s; }

/* ===================================
   Responsive Design
   =================================== */
@media (max-width: 1024px) {
    .hero-container {
        grid-template-columns: 1fr;
        gap: 3rem;
    }

    .title-main {
        font-size: 3rem;
    }

    .title-sub {
        font-size: 1.5rem;
    }

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

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

    .features-list {
        grid-template-columns: 1fr;
    }

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

@media (max-width: 768px) {
    .nav-menu {
        display: none;
    }

    .hero {
        padding: 6rem 1.5rem 3rem;
    }

    .hero-container {
        gap: 2rem;
    }

    .title-main {
        font-size: 2.5rem;
    }

    .title-sub {
        font-size: 1.25rem;
    }

    .hero-description {
        font-size: 1rem;
    }

    .hero-actions {
        flex-direction: column;
    }

    .hero-actions .btn {
        width: 100%;
        justify-content: center;
    }

    .value-prop-container {
        grid-template-columns: 1fr;
        gap: 2rem;
    }

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

    .section-container {
        padding: var(--spacing-2xl) 1.5rem;
    }

    .section-header h2 {
        font-size: 2rem;
    }

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

    .footer-links {
        grid-template-columns: 1fr;
        gap: 2rem;
    }

    .cta-content h2 {
        font-size: 2rem;
    }

    .cta-actions {
        flex-direction: column;
    }

    .cta-actions .btn {
        width: 100%;
        justify-content: center;
    }
}

@media (max-width: 480px) {
    .nav-container {
        padding: 1rem;
    }

    .logo-img {
        width: 24px;
        height: 24px;
    }

    .title-main {
        font-size: 2rem;
    }

    .section-header h2 {
        font-size: 1.75rem;
    }
}

/* ===================================
   Performance Optimizations
   =================================== */
.fade-in {
    will-change: opacity, transform;
}

.hero-card,
.role-card,
.capability-card,
.feature-item,
.tech-card {
    will-change: transform, box-shadow;
}

/* Smooth scrolling for anchor links */
html {
    scroll-behavior: smooth;
}

/* Selection styling */
::selection {
    background: var(--color-primary);
    color: white;
}

::-moz-selection {
    background: var(--color-primary);
    color: white;
}

/* Focus styles for accessibility */
a:focus,
button:focus {
    outline: 2px solid var(--color-primary);
    outline-offset: 2px;
}

/* Print styles */
@media print {
    .nav,
    .hero-actions,
    .cta,
    .footer {
        display: none;
    }

    .fade-in {
        opacity: 1 !important;
        transform: none !important;
    }
}