/* ========== Custom Scrollbar ========== */
::-webkit-scrollbar {
    width: 8px;
}

::-webkit-scrollbar-track {
    background: var(--bg-primary);
}

::-webkit-scrollbar-thumb {
    background: var(--text-tertiary);
    border-radius: 4px;
}

::-webkit-scrollbar-thumb:hover {
    background: var(--text-secondary);
}

/* ========== Page Loader ========== */
.page-loader {
    position: fixed;
    inset: 0;
    z-index: 9999;
    background: var(--bg-primary);
    display: flex;
    align-items: center;
    justify-content: center;
    transition: opacity 0.5s ease, visibility 0.5s ease;
}

.page-loader.hidden {
    opacity: 0;
    visibility: hidden;
    pointer-events: none;
}

.loader-spinner {
    position: relative;
    width: 48px;
    height: 48px;
}

.loader-ring {
    width: 100%;
    height: 100%;
    border: 3px solid transparent;
    border-top-color: var(--accent);
    border-right-color: var(--accent);
    border-radius: 50%;
    animation: loaderSpin 0.8s linear infinite;
}

@keyframes loaderSpin {
    to { transform: rotate(360deg); }
}

/* ========== Mobile Menu ========== */
.mobile-menu {
    position: fixed;
    top: var(--nav-height);
    left: 0;
    right: 0;
    bottom: 0;
    z-index: 999;
    display: none;
    background: transparent;
}

.mobile-menu-overlay {
    position: absolute;
    inset: 0;
    background: rgba(0, 0, 0, 0);
    pointer-events: none;
    z-index: 1;
    transition: background 0.3s ease;
}

.mobile-menu.active .mobile-menu-overlay {
    background: rgba(0, 0, 0, 0.4);
    pointer-events: auto;
}

.mobile-nav-panel {
    position: relative;
    z-index: 2;
    background: #ffffff;
    max-height: calc(100vh - var(--nav-height));
    overflow-y: auto;
    overflow-x: hidden;
    padding: 24px 0;
    transform: translateY(-100%);
    opacity: 0;
    transition: transform 0.35s cubic-bezier(0.4, 0, 0.2, 1), opacity 0.3s ease;
}

.mobile-menu.active .mobile-nav-panel {
    transform: translateY(0);
    opacity: 1;
}

.mobile-nav-brand {
    padding: 0 24px 20px;
    border-bottom: 1px solid rgba(0, 0, 0, 0.06);
    margin-bottom: 16px;
}

.mobile-nav-brand-logo {
    display: flex;
    align-items: center;
    gap: 10px;
    font-size: 18px;
    font-weight: 700;
    color: var(--text-primary);
    margin-bottom: 4px;
}

.mobile-nav-brand-logo .logo-icon {
    font-size: 20px;
    background: linear-gradient(135deg, #2997ff, #a855f7);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
}

.mobile-nav-brand-desc {
    font-size: 13px;
    color: var(--text-tertiary);
}

.mobile-nav-links {
    list-style: none;
    padding: 0 16px;
    margin: 0;
}

.mobile-nav-links li {
    opacity: 0;
    transform: translateY(-8px);
    transition: opacity 0.3s ease, transform 0.3s ease;
}

.mobile-menu.active .mobile-nav-links li {
    opacity: 1;
    transform: translateY(0);
}

.mobile-nav-links li:nth-child(1) { transition-delay: 0.08s; }
.mobile-nav-links li:nth-child(2) { transition-delay: 0.12s; }
.mobile-nav-links li:nth-child(3) { transition-delay: 0.16s; }
.mobile-nav-links li:nth-child(4) { transition-delay: 0.20s; }
.mobile-nav-links li:nth-child(5) { transition-delay: 0.24s; }
.mobile-nav-links li:nth-child(6) { transition-delay: 0.28s; }

.mobile-nav-links a {
    display: flex;
    align-items: center;
    min-height: 52px;
    padding: 14px 16px;
    font-size: 16px;
    font-weight: 500;
    color: var(--text-primary);
    border-radius: 12px;
    transition: background 0.2s ease, color 0.2s ease;
    -webkit-tap-highlight-color: transparent;
    touch-action: manipulation;
    user-select: none;
}

.mobile-nav-links a:hover {
    background: rgba(41, 151, 255, 0.06);
    color: var(--accent);
}

.mobile-nav-links a:active {
    background: rgba(41, 151, 255, 0.12);
    color: var(--accent);
}

.mobile-nav-links a[target="_blank"]::after {
    content: '↗';
    margin-left: auto;
    font-size: 14px;
    color: var(--text-tertiary);
}

.mobile-nav-divider {
    height: 1px;
    background: rgba(0, 0, 0, 0.06);
    margin: 16px 24px;
}

.mobile-nav-cta {
    display: block;
    margin: 8px 24px 0;
    padding: 16px;
    text-align: center;
    font-size: 16px;
    font-weight: 600;
    color: #ffffff;
    background: linear-gradient(135deg, #2997ff, #a855f7);
    border-radius: 14px;
    opacity: 0;
    transform: translateY(10px);
    transition: opacity 0.3s ease, transform 0.3s ease, background 0.2s ease;
    -webkit-tap-highlight-color: transparent;
    touch-action: manipulation;
    user-select: none;
}

.mobile-menu.active .mobile-nav-cta {
    opacity: 1;
    transform: translateY(0);
    transition-delay: 0.32s;
}

.mobile-nav-cta:active {
    opacity: 0.9;
    transform: scale(0.98);
}

.mobile-nav-footer {
    padding: 24px;
    margin-top: 24px;
    border-top: 1px solid rgba(0, 0, 0, 0.06);
    text-align: center;
}

.mobile-nav-footer p {
    font-size: 12px;
    color: var(--text-tertiary);
    line-height: 1.6;
}

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

:root {
    --bg-primary: #ffffff;
    --bg-secondary: #f5f5f7;
    --bg-card: #ffffff;
    --bg-card-hover: #f5f5f7;
    --text-primary: #1d1d1f;
    --text-secondary: #6e6e73;
    --text-tertiary: #86868b;
    --accent: #0066cc;
    --accent-hover: #0052a3;
    --accent-glow: rgba(0, 102, 204, 0.1);
    --gradient-start: #0066cc;
    --gradient-mid: #5b4cdb;
    --gradient-end: #7c3aed;
    --border-color: rgba(0, 0, 0, 0.08);
    --border-hover: rgba(0, 0, 0, 0.15);
    --nav-height: 52px;
    --radius-sm: 8px;
    --radius-md: 16px;
    --radius-lg: 24px;
    --radius-xl: 32px;
    --transition: 0.3s cubic-bezier(0.4, 0, 0.2, 1);
    --font-sans: -apple-system, BlinkMacSystemFont, "SF Pro Display", "SF Pro Text", "Helvetica Neue", "PingFang SC", "Noto Sans CJK SC", sans-serif;
}

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

body {
    font-family: var(--font-sans);
    background: var(--bg-primary);
    color: var(--text-primary);
    line-height: 1.6;
    overflow-x: hidden;
}

.container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 24px;
}

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

/* ========== AI Chat Widget ========== */
.ai-chat-toggle {
    position: fixed;
    bottom: 28px;
    right: 28px;
    width: 60px;
    height: 60px;
    border-radius: 50%;
    background: linear-gradient(135deg, #0066cc, #5b4cdb, #7c3aed);
    border: none;
    cursor: pointer;
    display: flex;
    align-items: center;
    justify-content: center;
    box-shadow: 0 8px 32px rgba(0, 102, 204, 0.35), 0 2px 8px rgba(0, 0, 0, 0.1);
    z-index: 9998;
    transition: transform 0.3s cubic-bezier(0.4, 0, 0.2, 1), box-shadow 0.3s ease;
    animation: chatPulse 3s ease-in-out infinite;
}

.ai-chat-toggle:hover {
    transform: scale(1.08);
    box-shadow: 0 10px 40px rgba(0, 102, 204, 0.45), 0 4px 12px rgba(0, 0, 0, 0.12);
}

.ai-chat-toggle:active {
    transform: scale(0.96);
}

.ai-chat-toggle svg {
    width: 28px;
    height: 28px;
    fill: none;
    stroke: #fff;
    stroke-width: 1.8;
    stroke-linecap: round;
    stroke-linejoin: round;
    transition: opacity 0.2s ease;
}

.ai-chat-toggle .icon-chat,
.ai-chat-toggle .icon-close {
    position: absolute;
    transition: opacity 0.25s ease, transform 0.25s ease;
}

.ai-chat-toggle.active .icon-chat {
    opacity: 0;
    transform: scale(0.6);
}

.ai-chat-toggle.active .icon-close {
    opacity: 1;
    transform: scale(1);
}

.ai-chat-toggle:not(.active) .icon-close {
    opacity: 0;
    transform: scale(0.6);
}

.ai-chat-toggle:not(.active) .icon-chat {
    opacity: 1;
    transform: scale(1);
}

@keyframes chatPulse {
    0%, 100% { box-shadow: 0 8px 32px rgba(0, 102, 204, 0.35), 0 2px 8px rgba(0, 0, 0, 0.1); }
    50% { box-shadow: 0 8px 40px rgba(91, 76, 219, 0.4), 0 2px 12px rgba(0, 0, 0, 0.12); }
}

.ai-chat-window {
    position: fixed;
    bottom: 100px;
    right: 28px;
    width: 420px;
    height: 560px;
    max-height: calc(100vh - 140px);
    border-radius: var(--radius-lg);
    background: var(--bg-primary);
    box-shadow: 0 24px 80px rgba(0, 0, 0, 0.15), 0 4px 16px rgba(0, 0, 0, 0.08);
    z-index: 9997;
    display: flex;
    flex-direction: column;
    overflow: hidden;
    opacity: 0;
    visibility: hidden;
    transform: translateY(20px) scale(0.95);
    transition: opacity 0.35s cubic-bezier(0.4, 0, 0.2, 1),
                visibility 0.35s cubic-bezier(0.4, 0, 0.2, 1),
                transform 0.35s cubic-bezier(0.4, 0, 0.2, 1);
    pointer-events: none;
}

.ai-chat-window.open {
    opacity: 1;
    visibility: visible;
    transform: translateY(0) scale(1);
    pointer-events: auto;
}

.ai-chat-header {
    padding: 18px 20px;
    background: linear-gradient(135deg, #0066cc, #5b4cdb, #7c3aed);
    color: #fff;
    flex-shrink: 0;
}

.ai-chat-header-inner {
    display: flex;
    align-items: center;
    gap: 12px;
}

.ai-chat-header-icon {
    width: 36px;
    height: 36px;
    border-radius: 10px;
    background: rgba(255, 255, 255, 0.2);
    display: flex;
    align-items: center;
    justify-content: center;
    flex-shrink: 0;
}

.ai-chat-header-icon svg {
    width: 20px;
    height: 20px;
    fill: none;
    stroke: #fff;
    stroke-width: 2;
    stroke-linecap: round;
    stroke-linejoin: round;
}

.ai-chat-header-text h3 {
    font-size: 16px;
    font-weight: 700;
    margin: 0;
    letter-spacing: -0.01em;
}

.ai-chat-header-text p {
    font-size: 12px;
    opacity: 0.8;
    margin: 2px 0 0;
}

.ai-chat-status {
    display: flex;
    align-items: center;
    gap: 6px;
    margin-left: auto;
    font-size: 11px;
    opacity: 0.8;
}

.ai-chat-status-dot {
    width: 7px;
    height: 7px;
    border-radius: 50%;
    background: #4ade80;
    flex-shrink: 0;
}

.ai-chat-status-dot.error {
    background: #f87171;
}

.ai-chat-new-btn {
    width: 44px;
    height: 44px;
    border-radius: 50%;
    border: none;
    background: linear-gradient(135deg, #0066cc, #5b4cdb);
    color: #fff;
    cursor: pointer;
    display: flex;
    align-items: center;
    justify-content: center;
    flex-shrink: 0;
    transition: transform 0.2s ease, opacity 0.2s ease;
    opacity: 0.7;
}

.ai-chat-new-btn:hover {
    opacity: 1;
}

.ai-chat-new-btn:active {
    transform: scale(0.95);
}

.ai-chat-new-btn svg {
    width: 20px;
    height: 20px;
}

.ai-chat-messages {
    flex: 1;
    overflow-y: auto;
    padding: 20px;
    display: flex;
    flex-direction: column;
    gap: 16px;
    scroll-behavior: smooth;
}

.ai-chat-messages::-webkit-scrollbar {
    width: 4px;
}

.ai-chat-messages::-webkit-scrollbar-track {
    background: transparent;
}

.ai-chat-messages::-webkit-scrollbar-thumb {
    background: var(--text-tertiary);
    border-radius: 2px;
}

.ai-message {
    display: flex;
    gap: 10px;
    max-width: 88%;
    animation: msgIn 0.3s cubic-bezier(0.4, 0, 0.2, 1);
}

@keyframes msgIn {
    from { opacity: 0; transform: translateY(8px); }
    to { opacity: 1; transform: translateY(0); }
}

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

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

.ai-message-avatar {
    width: 32px;
    height: 32px;
    border-radius: 10px;
    display: flex;
    align-items: center;
    justify-content: center;
    flex-shrink: 0;
    font-size: 14px;
}

.ai-message.user .ai-message-avatar {
    background: linear-gradient(135deg, #0066cc, #5b4cdb);
    color: #fff;
}

.ai-message.assistant .ai-message-avatar {
    background: var(--bg-secondary);
    color: var(--accent);
}

.ai-message-bubble {
    padding: 12px 16px;
    border-radius: 16px;
    font-size: 14px;
    line-height: 1.65;
    word-break: break-word;
    white-space: pre-wrap;
}

.ai-message.user .ai-message-bubble {
    background: linear-gradient(135deg, #0066cc, #5b4cdb);
    color: #fff;
    border-bottom-right-radius: 6px;
}

.ai-message.assistant .ai-message-bubble {
    background: var(--bg-secondary);
    color: var(--text-primary);
    border: 1px solid var(--border-color);
    border-bottom-left-radius: 6px;
}

.ai-message-bubble code {
    background: rgba(0, 0, 0, 0.06);
    padding: 2px 6px;
    border-radius: 4px;
    font-family: "SF Mono", "Fira Code", "Cascadia Code", monospace;
    font-size: 13px;
}

.ai-message.user .ai-message-bubble code {
    background: rgba(255, 255, 255, 0.2);
}

.ai-typing-indicator {
    display: flex;
    gap: 4px;
    padding: 4px 0;
}

.ai-typing-indicator span {
    width: 7px;
    height: 7px;
    border-radius: 50%;
    background: var(--text-tertiary);
    animation: typingBounce 1.2s ease-in-out infinite;
}

.ai-typing-indicator span:nth-child(2) { animation-delay: 0.15s; }
.ai-typing-indicator span:nth-child(3) { animation-delay: 0.3s; }

@keyframes typingBounce {
    0%, 60%, 100% { transform: translateY(0); opacity: 0.4; }
    30% { transform: translateY(-6px); opacity: 1; }
}

.ai-chat-input-area {
    padding: 14px 16px;
    border-top: 1px solid var(--border-color);
    background: var(--bg-primary);
    flex-shrink: 0;
}

.ai-chat-input-row {
    display: flex;
    gap: 10px;
    align-items: flex-end;
}

.ai-chat-input {
    flex: 1;
    padding: 12px 16px;
    border: 1px solid var(--border-color);
    border-radius: 24px;
    font-size: 14px;
    font-family: var(--font-sans);
    color: var(--text-primary);
    background: var(--bg-secondary);
    resize: none;
    outline: none;
    transition: border-color 0.2s ease, box-shadow 0.2s ease;
    max-height: 120px;
    min-height: 44px;
    line-height: 1.5;
}

.ai-chat-input:focus {
    border-color: var(--accent);
    box-shadow: 0 0 0 3px var(--accent-glow);
    background: var(--bg-primary);
}

.ai-chat-input::placeholder {
    color: var(--text-tertiary);
}

.ai-chat-send {
    width: 44px;
    height: 44px;
    border-radius: 50%;
    border: none;
    background: linear-gradient(135deg, #0066cc, #5b4cdb);
    color: #fff;
    cursor: pointer;
    display: flex;
    align-items: center;
    justify-content: center;
    flex-shrink: 0;
    transition: transform 0.2s ease, opacity 0.2s ease;
}

.ai-chat-send:hover {
    transform: scale(1.05);
}

.ai-chat-send:active {
    transform: scale(0.95);
}

.ai-chat-send:disabled {
    opacity: 0.5;
    cursor: not-allowed;
    transform: none;
}

.ai-chat-send svg {
    width: 20px;
    height: 20px;
    fill: none;
    stroke: #fff;
    stroke-width: 2;
    stroke-linecap: round;
    stroke-linejoin: round;
}

.ai-chat-footer {
    text-align: center;
    padding: 6px 16px 10px;
    font-size: 11px;
    color: var(--text-tertiary);
    background: var(--bg-primary);
    border-top: 1px solid var(--border-color);
    flex-shrink: 0;
}

/* Markdown rendering in chat messages */
.ai-code-block {
    background: rgba(0, 0, 0, 0.35);
    color: #e2e8f0;
    padding: 12px 14px;
    border-radius: 8px;
    font-family: 'JetBrains Mono', 'Fira Code', 'Cascadia Code', 'Consolas', monospace;
    font-size: 13px;
    line-height: 1.6;
    overflow-x: auto;
    margin: 8px 0;
    white-space: pre;
}

.ai-code-block code {
    background: none;
    padding: 0;
    font-size: inherit;
}

.ai-code-inline {
    background: rgba(0, 0, 0, 0.25);
    color: #e2e8f0;
    padding: 2px 6px;
    border-radius: 4px;
    font-family: 'JetBrains Mono', 'Fira Code', 'Consolas', monospace;
    font-size: 12px;
}

.ai-message.assistant .ai-message-bubble ul {
    margin: 6px 0;
    padding-left: 20px;
}

.ai-message.assistant .ai-message-bubble li {
    margin-bottom: 4px;
}

.ai-message.assistant .ai-message-bubble strong {
    font-weight: 700;
}

.ai-message.assistant .ai-message-bubble em {
    font-style: italic;
}

/* ========== Navigation ========== */
.nav {
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    z-index: 1000;
    height: var(--nav-height);
    background: rgba(255, 255, 255, 0.8);
    backdrop-filter: saturate(180%) blur(20px);
    -webkit-backdrop-filter: saturate(180%) blur(20px);
    border-bottom: 1px solid var(--border-color);
    transition: var(--transition);
}

.nav-container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 24px;
    height: 100%;
    display: flex;
    align-items: center;
    justify-content: space-between;
}

.nav-logo {
    display: flex;
    align-items: center;
    gap: 8px;
    font-size: 18px;
    font-weight: 600;
    letter-spacing: -0.02em;
    transition: var(--transition);
}

.nav-logo:hover {
    opacity: 0.8;
}

.logo-icon {
    font-size: 20px;
    background: linear-gradient(135deg, var(--gradient-start), var(--gradient-end));
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
}

.nav-links {
    display: flex;
    align-items: center;
    gap: 36px;
    list-style: none;
}

.nav-links a {
    font-size: 14px;
    color: var(--text-secondary);
    transition: var(--transition);
    letter-spacing: -0.01em;
}

.nav-links a:hover {
    color: var(--text-primary);
}

.nav-cta {
    padding: 8px 20px;
    font-size: 14px;
    font-weight: 500;
    background: var(--accent);
    color: #ffffff;
    border-radius: 980px;
    transition: var(--transition);
    letter-spacing: -0.01em;
}

.nav-cta:hover {
    background: var(--accent-hover);
    transform: scale(1.02);
}

.nav-toggle {
    display: none;
    flex-direction: column;
    gap: 5px;
    background: none;
    border: none;
    cursor: pointer;
    padding: 4px;
}

.nav-toggle span {
    display: block;
    width: 20px;
    height: 1.5px;
    background: var(--text-primary);
    transition: var(--transition);
    border-radius: 2px;
}

/* ========== Hero Section ========== */
.hero {
    min-height: 100vh;
    display: flex;
    align-items: center;
    position: relative;
    overflow: hidden;
    padding: 0 0 20px;
}

.hero-bg {
    position: absolute;
    inset: 0;
    background:
        radial-gradient(ellipse 80% 60% at 50% 0%, rgba(0, 102, 204, 0.1) 0%, transparent 60%),
        radial-gradient(ellipse 60% 50% at 80% 50%, rgba(91, 76, 219, 0.08) 0%, transparent 50%),
        radial-gradient(ellipse 60% 50% at 20% 80%, rgba(124, 58, 237, 0.06) 0%, transparent 50%);
    pointer-events: none;
}

.hero-content {
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 24px;
    position: relative;
    z-index: 1;
    text-align: center;
    width: 100%;
}

.hero-badge {
    display: inline-flex;
    align-items: center;
    gap: 6px;
    padding: 6px 16px;
    font-size: 13px;
    font-weight: 500;
    color: var(--accent);
    background: var(--accent-glow);
    border: 1px solid rgba(0, 102, 204, 0.2);
    border-radius: 980px;
    margin-bottom: 32px;
    letter-spacing: -0.01em;
}

.hero-title {
    font-size: clamp(48px, 8vw, 96px);
    font-weight: 700;
    line-height: 1.05;
    letter-spacing: -0.04em;
    margin-bottom: 24px;
    color: var(--text-primary);
}

.gradient-text {
    background: linear-gradient(135deg, var(--gradient-start), var(--gradient-mid), var(--gradient-end));
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
    background-size: 200% 200%;
    animation: gradientShift 6s ease infinite;
}

@keyframes gradientShift {
    0%, 100% { background-position: 0% 50%; }
    50% { background-position: 100% 50%; }
}

.hero-subtitle {
    font-size: clamp(18px, 2.5vw, 28px);
    color: var(--text-secondary);
    max-width: 640px;
    margin: 0 auto 40px;
    line-height: 1.5;
    letter-spacing: -0.02em;
    font-weight: 400;
}

/* ========== Hero Scroll Hint ========== */
.hero-scroll-hint {
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: 8px;
    margin-top: 40px;
    opacity: 0;
    animation: fadeInUp 0.8s ease forwards;
    animation-delay: 1.2s;
    transition: opacity 0.4s ease;
}

@keyframes fadeInUp {
    from {
        opacity: 0;
        transform: translateY(20px);
    }
    to {
        opacity: 1;
        transform: translateY(0);
    }
}

.scroll-mouse {
    width: 26px;
    height: 42px;
    border: 2px solid var(--text-tertiary);
    border-radius: 13px;
    position: relative;
    display: flex;
    justify-content: center;
    padding-top: 8px;
}

.scroll-wheel {
    width: 3px;
    height: 8px;
    background: var(--text-secondary);
    border-radius: 2px;
    animation: scrollWheel 1.5s ease-in-out infinite;
}

@keyframes scrollWheel {
    0%, 100% {
        opacity: 1;
        transform: translateY(0);
    }
    50% {
        opacity: 0.2;
        transform: translateY(10px);
    }
}

.scroll-text {
    font-size: 13px;
    color: var(--text-tertiary);
    letter-spacing: 0.05em;
}

/* Hero Stats */
.hero-stats {
    display: flex;
    align-items: center;
    justify-content: center;
    gap: 40px;
    flex-wrap: wrap;
}

.stat {
    display: flex;
    align-items: baseline;
    gap: 2px;
    justify-content: center;
}

.stat-number {
    font-size: 48px;
    font-weight: 700;
    letter-spacing: -0.03em;
    color: var(--text-primary);
    line-height: 1;
}

.stat-suffix {
    font-size: 28px;
    font-weight: 600;
    color: var(--text-secondary);
    line-height: 1;
}

.stat-label {
    font-size: 14px;
    color: var(--text-tertiary);
    margin-left: 4px;
}

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


/* ========== Section Common ========== */
.section {
    padding: 120px 0;
    position: relative;
}

.section-dark {
    background: var(--bg-secondary);
}

.section-header {
    text-align: center;
    margin-bottom: 72px;
}

.section-tag {
    display: inline-block;
    font-size: 14px;
    font-weight: 600;
    color: var(--accent);
    text-transform: uppercase;
    letter-spacing: 0.1em;
    margin-bottom: 16px;
}

.section-title {
    font-size: clamp(36px, 5vw, 56px);
    font-weight: 700;
    letter-spacing: -0.03em;
    line-height: 1.1;
    margin-bottom: 16px;
}

.section-desc {
    font-size: 19px;
    color: var(--text-secondary);
    width: 100%;
    margin: 0 auto;
    line-height: 1.5;
    white-space: nowrap;
    text-align: center;
}

/* ========== Services Grid ========== */
.services-grid {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 20px;
}

.service-card {
    background: var(--bg-card);
    border: 1px solid var(--border-color);
    border-radius: var(--radius-lg);
    padding: 36px;
    transition: var(--transition);
    position: relative;
    overflow: hidden;
}

.service-card::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    height: 1px;
    background: linear-gradient(90deg, transparent, var(--accent), transparent);
    opacity: 0;
    transition: var(--transition);
}

.service-card:hover {
    background: var(--bg-card-hover);
    border-color: var(--border-hover);
    transform: translateY(-4px);
}

.service-card:hover::before {
    opacity: 1;
}

.service-icon {
    width: 64px;
    height: 64px;
    margin-bottom: 20px;
    display: block;
    color: var(--accent);
}

.service-icon svg {
    width: 100%;
    height: 100%;
}

.service-title {
    font-size: 22px;
    font-weight: 600;
    letter-spacing: -0.02em;
    margin-bottom: 12px;
}

.service-desc {
    font-size: 15px;
    color: var(--text-secondary);
    line-height: 1.6;
    margin-bottom: 20px;
}

.service-features {
    list-style: none;
    display: flex;
    flex-direction: column;
    gap: 8px;
}

.service-features li {
    font-size: 14px;
    color: var(--text-tertiary);
    line-height: 1.5;
}

/* ========== About Section ========== */
.about-content {
    max-width: 800px;
    margin: 0 auto;
}

.about-paragraph {
    font-size: 16px;
    color: var(--text-secondary);
    line-height: 1.8;
    margin-bottom: 20px;
}

.about-paragraph:last-of-type {
    margin-bottom: 40px;
}

.about-paragraph strong {
    color: var(--text-primary);
    font-weight: 600;
}

.about-stats {
    display: flex;
    align-items: center;
    justify-content: center;
    gap: 32px;
    padding: 32px 0;
    border-top: 1px solid var(--border-color);
    border-bottom: 1px solid var(--border-color);
}

.about-stat {
    text-align: center;
}

.about-stat-number {
    display: block;
    font-size: 36px;
    font-weight: 700;
    letter-spacing: -0.03em;
    color: var(--text-primary);
    line-height: 1;
    margin-bottom: 8px;
}

.about-stat-label {
    font-size: 14px;
    color: var(--text-tertiary);
}

.about-stat-divider {
    width: 1px;
    height: 48px;
    background: var(--border-color);
}

/* ========== Partners Section ========== */
.partners-grid {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 16px;
    max-width: 800px;
    margin: 0 auto;
}

.partner-card {
    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: center;
    padding: 32px 24px;
    background: var(--bg-card);
    border: 1px solid var(--border-color);
    border-radius: var(--radius-md);
    transition: all 0.4s cubic-bezier(0.4, 0, 0.2, 1);
    text-align: center;
    position: relative;
    overflow: hidden;
}

.partner-card::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    height: 2px;
    background: linear-gradient(90deg, transparent, var(--accent), transparent);
    opacity: 0;
    transition: opacity 0.4s ease;
}

.partner-card::after {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    background: radial-gradient(circle at var(--mouse-x, 50%) var(--mouse-y, 50%), rgba(0, 102, 204, 0.06) 0%, transparent 60%);
    opacity: 0;
    transition: opacity 0.4s ease;
    pointer-events: none;
}

.partner-card:hover {
    border-color: rgba(0, 102, 204, 0.15);
    transform: translateY(-4px);
    box-shadow: 0 4px 20px rgba(0, 102, 204, 0.08);
}

.partner-card:hover::before {
    opacity: 1;
}

.partner-card:hover::after {
    opacity: 1;
}

.partner-name {
    font-size: 18px;
    font-weight: 600;
    color: var(--text-primary);
    margin-bottom: 6px;
}

.partner-desc {
    font-size: 13px;
    color: var(--text-tertiary);
}

/* ========== Advantages ========== */
.advantages-grid {
    display: grid;
    grid-template-columns: repeat(2, 1fr);
    gap: 2px;
}

.advantage-item {
    padding: 48px 40px;
    background: var(--bg-primary);
    position: relative;
    transition: all 0.4s cubic-bezier(0.4, 0, 0.2, 1);
    border: 1px solid transparent;
    border-radius: 12px;
    overflow: hidden;
}

.advantage-item::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    height: 2px;
    background: linear-gradient(90deg, transparent, var(--accent), transparent);
    opacity: 0;
    transition: opacity 0.4s ease;
}

.advantage-item::after {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    background: radial-gradient(circle at var(--mouse-x, 50%) var(--mouse-y, 50%), rgba(0, 102, 204, 0.04) 0%, transparent 60%);
    opacity: 0;
    transition: opacity 0.4s ease;
    pointer-events: none;
}

.advantage-item:hover {
    border-color: rgba(0, 102, 204, 0.15);
    box-shadow: 0 4px 20px rgba(0, 102, 204, 0.08);
}

.advantage-item:hover::before {
    opacity: 1;
}

.advantage-item:hover::after {
    opacity: 1;
}

.advantage-number {
    font-size: 14px;
    font-weight: 600;
    color: var(--accent);
    letter-spacing: 0.05em;
    margin-bottom: 16px;
    font-variant-numeric: tabular-nums;
}

.advantage-title {
    font-size: 24px;
    font-weight: 600;
    letter-spacing: -0.02em;
    margin-bottom: 12px;
    line-height: 1.3;
}

.advantage-desc {
    font-size: 15px;
    color: var(--text-secondary);
    line-height: 1.6;
}

/* ========== Benchmark Customers ========== */
.benchmark-grid {
    display: grid;
    grid-template-columns: repeat(4, 1fr);
    gap: 20px;
    max-width: 900px;
    margin: 0 auto 60px;
}

.benchmark-item {
    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: center;
    padding: 40px 24px;
    background: var(--bg-card);
    border: 1px solid var(--border-color);
    border-radius: var(--radius-md);
    transition: var(--transition);
    text-align: center;
}

.benchmark-item:hover {
    background: var(--bg-card-hover);
    border-color: var(--border-hover);
    transform: translateY(-4px);
}

.benchmark-icon {
    font-size: 40px;
    margin-bottom: 16px;
}

.benchmark-name {
    font-size: 20px;
    font-weight: 600;
    color: var(--text-primary);
    margin-bottom: 8px;
}

.benchmark-industry {
    font-size: 13px;
    color: var(--text-tertiary);
}

/* ========== Logo Grid (Static Two-Row) ========== */
.logo-grid {
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: 48px;
    margin: 0 auto;
}

.logo-row {
    display: flex;
    justify-content: center;
    flex-wrap: nowrap;
    gap: 24px;
    max-width: 1600px;
    width: 100%;
}

.logo-card {
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: 8px;
    padding: 20px 20px;
    transition: all 0.4s cubic-bezier(0.4, 0, 0.2, 1);
    text-align: center;
    flex: 0 0 auto;
    width: 150px;
    border-radius: 16px;
    background: var(--bg-card);
    border: 1px solid var(--border-color);
    position: relative;
    overflow: hidden;
}

.logo-card::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    height: 2px;
    background: linear-gradient(90deg, transparent, var(--accent), transparent);
    opacity: 0;
    transition: opacity 0.4s ease;
}

.logo-card::after {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    background: radial-gradient(circle at var(--mouse-x, 50%) var(--mouse-y, 50%), rgba(0, 102, 204, 0.06) 0%, transparent 60%);
    opacity: 0;
    transition: opacity 0.4s ease;
    pointer-events: none;
}

.logo-card:hover {
    transform: translateY(-4px);
    border-color: rgba(0, 102, 204, 0.15);
    box-shadow: 0 4px 20px rgba(0, 102, 204, 0.08);
}

.logo-card:hover::before {
    opacity: 1;
}

.logo-card:hover::after {
    opacity: 1;
}

.logo-img {
    width: 110px;
    height: 110px;
    object-fit: contain;
    margin-bottom: 2px;
}

.logo-name {
    font-size: 15px;
    font-weight: 600;
    color: var(--text-primary);
    line-height: 1.3;
}

.logo-industry {
    font-size: 12px;
    color: var(--text-tertiary);
    line-height: 1.3;
}

/* ========== Cases ========== */
#cases .section-header {
    margin-bottom: 72px;
}

#cases .section-title {
    font-size: clamp(42px, 6vw, 68px);
}

#cases .section-desc {
    font-size: 21px;
}
.cases-grid {
    display: grid;
    grid-template-columns: repeat(2, 1fr);
    gap: 20px;
}

.case-card {
    background: var(--bg-card);
    border: 1px solid var(--border-color);
    border-radius: var(--radius-lg);
    padding: 40px;
    transition: var(--transition);
}

.case-card:hover {
    border-color: var(--border-hover);
    transform: translateY(-4px);
}

.case-industry {
    display: inline-block;
    font-size: 13px;
    font-weight: 600;
    color: var(--accent);
    background: var(--accent-glow);
    padding: 4px 12px;
    border-radius: 980px;
    margin-bottom: 16px;
    letter-spacing: 0.02em;
}

.case-title {
    font-size: 22px;
    font-weight: 600;
    letter-spacing: -0.02em;
    margin-bottom: 12px;
    line-height: 1.3;
}

.case-desc {
    font-size: 15px;
    color: var(--text-secondary);
    line-height: 1.6;
    margin-bottom: 20px;
}

.case-tags {
    display: flex;
    gap: 8px;
    flex-wrap: wrap;
}

.case-tags span {
    font-size: 13px;
    color: var(--text-tertiary);
    background: rgba(0, 0, 0, 0.04);
    padding: 4px 12px;
    border-radius: 980px;
    border: 1px solid var(--border-color);
}

/* ========== Buttons ========== */
.btn {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    gap: 8px;
    padding: 14px 28px;
    font-size: 17px;
    font-weight: 500;
    border-radius: 980px;
    border: none;
    cursor: pointer;
    transition: var(--transition);
    letter-spacing: -0.02em;
    font-family: inherit;
}

.btn-primary {
    background: var(--accent);
    color: #ffffff;
}

.btn-primary:hover {
    background: var(--accent-hover);
    transform: scale(1.04);
    box-shadow: 0 8px 30px rgba(0, 102, 204, 0.2);
}

.btn-large {
    padding: 18px 48px;
    font-size: 19px;
    width: 100%;
    max-width: 320px;
}

/* ========== CTA Section ========== */
.cta-section {
    padding: 120px 0;
    position: relative;
    overflow: hidden;
}

.cta-bg {
    position: absolute;
    inset: 0;
    background:
        radial-gradient(ellipse 60% 50% at 50% 50%, rgba(0, 102, 204, 0.08) 0%, transparent 70%);
    pointer-events: none;
}

.cta-content {
    position: relative;
    z-index: 1;
    max-width: 600px;
    margin: 0 auto;
    text-align: center;
}

.cta-title {
    font-size: clamp(36px, 5vw, 52px);
    font-weight: 700;
    letter-spacing: -0.03em;
    line-height: 1.1;
    margin-bottom: 16px;
}

.cta-desc {
    font-size: 19px;
    color: var(--text-secondary);
    margin-bottom: 48px;
    line-height: 1.5;
}

.cta-links {
    display: flex;
    justify-content: center;
    gap: 16px;
    margin-bottom: 32px;
}

.cta-link-btn {
    display: inline-flex;
    align-items: center;
    gap: 8px;
    padding: 10px 24px;
    border-radius: 50px;
    font-size: 15px;
    font-weight: 500;
    color: var(--accent);
    background: rgba(41, 151, 255, 0.06);
    border: 1px solid rgba(41, 151, 255, 0.15);
    text-decoration: none;
    transition: all 0.3s ease;
}

.cta-link-btn:hover {
    background: rgba(41, 151, 255, 0.12);
    border-color: rgba(41, 151, 255, 0.3);
    transform: translateY(-1px);
    box-shadow: 0 4px 12px rgba(41, 151, 255, 0.1);
}

.cta-link-btn svg {
    flex-shrink: 0;
}

/* ========== Success Message ========= */
.cta-success {
    text-align: center;
    padding: 40px 20px;
    margin-top: 16px;
}

.success-icon {
    width: 64px;
    height: 64px;
    border-radius: 50%;
    background: #30d158;
    color: #fff;
    font-size: 32px;
    display: flex;
    align-items: center;
    justify-content: center;
    margin: 0 auto 20px;
    animation: successPop 0.5s ease;
}

@keyframes successPop {
    0%   { transform: scale(0); }
    70%  { transform: scale(1.15); }
    100% { transform: scale(1); }
}

.success-title {
    font-size: 24px;
    font-weight: 700;
    color: var(--text-primary);
    margin-bottom: 12px;
}

.success-desc {
    font-size: 16px;
    color: var(--text-secondary);
    line-height: 1.6;
    max-width: 480px;
    margin: 0 auto;
}

/* ========== QR Code Section ========= */
.cta-qr-section {
    text-align: center;
    margin-top: 48px;
    padding-top: 40px;
    border-top: 1px solid var(--border-color);
}

.cta-qr-title {
    font-size: 16px;
    font-weight: 600;
    color: var(--text-secondary);
    margin-bottom: 20px;
}

.cta-qr-card {
    display: inline-block;
    padding: 16px;
    background: #fff;
    border-radius: 16px;
    box-shadow: 0 4px 24px rgba(0, 0, 0, 0.08);
}

.cta-qr-img {
    width: 200px;
    height: auto;
    display: block;
    border-radius: 8px;
}

.cta-qr-hint {
    font-size: 13px;
    color: var(--text-tertiary);
    margin-top: 16px;
}

.cta-form {
    display: flex;
    flex-direction: column;
    gap: 16px;
}

.form-submit {
    display: flex;
    justify-content: center;
}

.form-row {
    display: grid;
    grid-template-columns: repeat(2, 1fr);
    gap: 16px;
}

.form-full {
    width: 100%;
}

.form-textarea {
    border-radius: var(--radius-lg);
    resize: vertical;
    min-height: 120px;
}

.form-textarea:focus {
    outline: none;
    border-color: var(--border-hover);
    box-shadow: 0 0 0 3px rgba(41, 151, 255, 0.1);
}

.form-textarea::placeholder {
    color: var(--text-tertiary);
}

.form-input {
    width: 100%;
    padding: 14px 18px;
    font-size: 16px;
    font-family: inherit;
    background: #fafafa;
    border: 1px solid var(--border-color);
    border-radius: var(--radius-md);
    color: var(--text-primary);
    transition: var(--transition);
    outline: none;
}

.form-input::placeholder {
    color: var(--text-tertiary);
}

.form-input:focus {
    border-color: var(--accent);
    background: rgba(0, 102, 204, 0.04);
    box-shadow: 0 0 0 3px var(--accent-glow);
}

.form-select {
    appearance: none;
    cursor: pointer;
    background-image: url("data:image/svg+xml,%3Csvg width='12' height='8' viewBox='0 0 12 8' fill='none' xmlns='http://www.w3.org/2000/svg'%3E%3Cpath d='M1 1.5L6 6.5L11 1.5' stroke='%2386868b' stroke-width='1.5' stroke-linecap='round' stroke-linejoin='round'/%3E%3C/svg%3E");
    background-repeat: no-repeat;
    background-position: right 16px center;
    padding-right: 40px;
}

.form-textarea {
    min-height: 100px;
    resize: vertical;
}

/* ========== Footer ========== */
.footer {
    border-top: 1px solid var(--border-color);
    padding: 64px 0 32px;
}

.footer-grid {
    display: grid;
    grid-template-columns: 2fr repeat(3, 1fr);
    gap: 48px;
    margin-bottom: 48px;
}

.footer-col {
    /* already styled by footer-grid */
}

/* ========== Back to Top Button ========== */
.back-to-top {
    position: fixed;
    bottom: 32px;
    right: 32px;
    width: 44px;
    height: 44px;
    border-radius: 50%;
    background: var(--bg-card);
    border: 1px solid var(--border-color);
    color: var(--text-secondary);
    font-size: 18px;
    cursor: pointer;
    display: flex;
    align-items: center;
    justify-content: center;
    opacity: 0;
    visibility: hidden;
    transform: translateY(10px);
    transition: opacity 0.3s ease, transform 0.3s ease, visibility 0.3s ease, var(--transition);
    z-index: 100;
}

.back-to-top.visible {
    opacity: 1;
    visibility: visible;
    transform: translateY(0);
}

.back-to-top:hover {
    background: var(--bg-card-hover);
    color: var(--accent);
    border-color: var(--border-hover);
}

.footer-brand {
    max-width: 280px;
}

.footer-desc {
    font-size: 14px;
    color: var(--text-tertiary);
    margin-top: 16px;
    line-height: 1.6;
}

.footer-title {
    font-size: 13px;
    font-weight: 600;
    color: var(--text-secondary);
    text-transform: uppercase;
    letter-spacing: 0.08em;
    margin-bottom: 16px;
}

.footer-links {
    list-style: none;
    display: flex;
    flex-direction: column;
    gap: 10px;
}

.footer-links a {
    font-size: 14px;
    color: var(--text-tertiary);
    transition: var(--transition);
}

.footer-links a:hover {
    color: var(--text-secondary);
}

.footer-links > li {
    font-size: 14px;
    color: var(--text-tertiary);
}

.footer-bottom {
    border-top: 1px solid var(--border-color);
    padding-top: 24px;
    text-align: center;
}

.footer-bottom p {
    font-size: 13px;
    color: var(--text-tertiary);
}

/* ========== Animations ========== */
.fade-in {
    opacity: 0;
    transform: translateY(24px);
    animation: fadeIn 0.8s ease forwards;
}

.fade-in:nth-child(1) { animation-delay: 0.1s; }
.fade-in:nth-child(2) { animation-delay: 0.25s; }
.fade-in:nth-child(3) { animation-delay: 0.4s; }
.fade-in:nth-child(4) { animation-delay: 0.55s; }
.fade-in:nth-child(5) { animation-delay: 0.7s; }

@keyframes fadeIn {
    to {
        opacity: 1;
        transform: translateY(0);
    }
}

/* Scroll reveal */
.reveal {
    opacity: 0;
    transform: translateY(32px);
    transition: opacity 0.6s ease, transform 0.6s ease;
}

.reveal.visible {
    opacity: 1;
    transform: translateY(0);
}

/* ========== Responsive ========== */
@media (max-width: 1024px) {
    .services-grid {
        grid-template-columns: repeat(2, 1fr);
    }

    .footer-grid {
        grid-template-columns: repeat(2, 1fr);
        gap: 36px;
    }

    .hero-visual {
        display: none;
    }

    .partners-grid {
        grid-template-columns: repeat(3, 1fr);
    }

}

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

    .nav-toggle {
        display: flex;
    }

    .mobile-menu {
        display: none !important;
        pointer-events: none;
        background: #ffffff !important;
    }

    .mobile-menu.active {
        display: block !important;
        pointer-events: auto;
        background: #ffffff !important;
    }

    /* 关闭时彻底禁用菜单内所有元素交互 */
    .mobile-menu:not(.active) .mobile-nav-links,
    .mobile-menu:not(.active) .mobile-nav-links a,
    .mobile-menu:not(.active) .mobile-nav-cta,
    .mobile-menu:not(.active) .mobile-menu-overlay {
        pointer-events: none !important;
    }

    /* 打开时恢复交互 */
    .mobile-menu.active .mobile-nav-links,
    .mobile-menu.active .mobile-nav-links a,
    .mobile-menu.active .mobile-nav-cta,
    .mobile-menu.active .mobile-menu-overlay {
        pointer-events: auto !important;
    }

    .nav-toggle.active span:nth-child(1) {
        transform: rotate(45deg) translate(4px, 4px);
    }

    .nav-toggle.active span:nth-child(2) {
        opacity: 0;
    }

    .nav-toggle.active span:nth-child(3) {
        transform: rotate(-45deg) translate(4px, -4px);
    }

    /* Lock body scroll and block clicks on page content when mobile menu is open */
    body.menu-open {
        overflow: hidden;
    }

    body.menu-open .hero,
    body.menu-open .section,
    body.menu-open .cta-section,
    body.menu-open .footer,
    body.menu-open .back-to-top {
        pointer-events: none;
    }

    /* Prevent links from being followed while menu is open, but allow menu links */
    body.menu-open a:not(.mobile-nav-links a):not(.mobile-nav-cta) {
        pointer-events: none !important;
    }

    .hero {
        padding-top: calc(var(--nav-height) + 40px);
        min-height: auto;
        padding-bottom: 60px;
    }

    .hero-title {
        font-size: 40px;
    }

    .hero-subtitle {
        font-size: 17px;
    }

    .hero-stats {
        gap: 24px;
        margin-top: 40px;
    }

    .hero-scroll-hint {
        margin-top: 24px;
    }

    .stat-number {
        font-size: 36px;
    }

    .stat-suffix {
        font-size: 20px;
    }

    .section {
        padding: 80px 0;
    }

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

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

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

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

    .about-stats {
        gap: 20px;
    }

    .about-stat-number {
        font-size: 28px;
    }

    .form-row {
        grid-template-columns: 1fr;
    }

    .footer-grid {
        grid-template-columns: 1fr;
        gap: 32px;
    }

    .footer-brand {
        max-width: 100%;
    }

    .cta-section {
        padding: 80px 0;
    }
}

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

    .hero-stats {
        flex-direction: column;
        gap: 20px;
    }

    .stat-divider {
        width: 40px;
        height: 1px;
    }

    .logo-card {
        padding: 16px 12px;
    }

    .logo-img {
        width: 56px;
        height: 56px;
    }

    .logo-name {
        font-size: 13px;
    }

    .logo-industry {
        font-size: 11px;
    }
}