/* :root {
    --bg-color: #0f1417;
    --bg-color-fff: #ffffff;
    --bg-color-nav: #ffffff;
    --text-color: #fff;
    --primary-color: #007aff;
    --light-color: #d3e3ff;
    --secondary-color: #2c2c2e;
    --accent-color: #ff3b30;
    --card-bg: #1c1c1e;
    --border-radius: 8px;
    --font-size: 48px;
    --line-height: 1.5;
    --bs-btn-hover-color: #212529;
    --text-gray-color: #6c757d;
} */

:root {
    --bg-deep: #0a0a0f;
    --bg-card: #12121a;
    --bg-card-hover: #181825;
    --border-subtle: #1e1e2e;
    --accent-primary: #6c8cff;
    --accent-secondary: #a78bfa;
    --accent-glow: rgba(108, 140, 255, 0.25);
    --text-primary: #e2e2ed;
    --text-secondary: #a0a0b8;
    --text-muted: #6b6b80;
    --gradient-hero: linear-gradient(135deg, #0f0f1a 0%, #0a0a14 30%, #0d0d20 60%, #0a0a16 100%);
    --gradient-card-border: linear-gradient(145deg, rgba(108, 140, 255, 0.3), rgba(167, 139, 250, 0.25), rgba(108, 140, 255, 0.15));
    --gradient-accent: linear-gradient(135deg, #6c8cff, #a78bfa);
    --gradient-text: linear-gradient(135deg, #b4c6ff, #c4b5fd);
    --radius-lg: 1.25rem;
    --radius-md: 1rem;
    --radius-sm: 0.75rem;
    --shadow-card: 0 4px 24px rgba(0, 0, 0, 0.4), 0 1px 3px rgba(0, 0, 0, 0.5);
    --shadow-glow: 0 0 60px rgba(108, 140, 255, 0.08), 0 0 120px rgba(167, 139, 250, 0.05);
    --transition-smooth: all 0.35s cubic-bezier(0.4, 0, 0.2, 1);
}

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

.btn:hover {
    color: var(--bs-btn-hover-color);
}

.max-w90 {
    max-width: 90% !important;
}

* {
    box-sizing: border-box;
}

body {
    font-family: 'Inter', 'Noto Sans SC', -apple-system, BlinkMacSystemFont, sans-serif;
    background: var(--bg-deep);
    color: var(--text-primary);
    min-height: 100vh;
    overflow-x: hidden;
    -webkit-font-smoothing: antialiased;
    -moz-osx-font-smoothing: grayscale;
    letter-spacing: 0.01em;
}

/* --- 全局背景光晕 --- */
.bg-ambient {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    pointer-events: none;
    z-index: 0;
    overflow: hidden;
}

.bg-ambient .orb {
    position: absolute;
    border-radius: 50%;
    filter: blur(140px);
    opacity: 0.06;
    animation: orbDrift 18s ease-in-out infinite alternate;
}

.bg-ambient .orb-1 {
    width: 600px;
    height: 600px;
    background: #6c8cff;
    top: -15%;
    left: -10%;
    animation-delay: 0s;
}

.bg-ambient .orb-2 {
    width: 500px;
    height: 500px;
    background: #a78bfa;
    bottom: -20%;
    right: -8%;
    animation-delay: -6s;
    animation-duration: 20s;
}

.bg-ambient .orb-3 {
    width: 350px;
    height: 350px;
    background: #5b7cfa;
    top: 55%;
    left: 50%;
    animation-delay: -12s;
    animation-duration: 22s;
    opacity: 0.04;
}

@keyframes orbDrift {
    0% {
        transform: translate(0, 0) scale(1);
    }

    33% {
        transform: translate(60px, -40px) scale(1.15);
    }

    66% {
        transform: translate(-30px, 50px) scale(0.9);
    }

    100% {
        transform: translate(20px, -20px) scale(1.08);
    }
}

nav.navbar {
    background: rgba(10, 10, 15, 0.7);
    backdrop-filter: blur(24px);
    -webkit-backdrop-filter: blur(24px);
    border-bottom: 1px solid var(--border-subtle);
    z-index: 1030;
    transition: var(--transition-smooth);
}

nav.navbar .navbar-brand {
    font-weight: 700;
    font-size: 1.35rem;
    letter-spacing: -0.02em;
    color: var(--text-primary);
    display: flex;
    align-items: center;
    gap: 0.55rem;
    transition: var(--transition-smooth);
}

.language-switcher button {
    color: #fff;
}

/* --- Hero 区域 --- */
.hero-section {
    position: relative;
    z-index: 1;
    padding: 7rem 0 5rem;
    text-align: center;
}

.hero-badge {
    display: inline-flex;
    align-items: center;
    gap: 0.5rem;
    background: rgba(108, 140, 255, 0.08);
    border: 1px solid rgba(108, 140, 255, 0.2);
    border-radius: 3rem;
    padding: 0.4rem 1.2rem;
    font-size: 0.8rem;
    font-weight: 600;
    color: var(--accent-primary);
    letter-spacing: 0.04em;
    text-transform: uppercase;
    margin-bottom: 2rem;
    animation: fadeInUp 0.7s ease-out;
}

.hero-badge .badge-icon {
    font-size: 1rem;
}

.hero-title {
    font-size: clamp(2.5rem, 6vw, 4.2rem);
    font-weight: 900;
    letter-spacing: -0.03em;
    line-height: 1.1;
    margin-bottom: 1.5rem;
    animation: fadeInUp 0.7s ease-out 0.1s both;
    background: var(--gradient-text);
    -webkit-background-clip: text;
    background-clip: text;
    -webkit-text-fill-color: transparent;
}

.hero-subtitle {
    font-size: clamp(1.05rem, 2vw, 1.25rem);
    color: var(--text-secondary);
    max-width: 680px;
    margin: 0 auto 2.5rem;
    font-weight: 400;
    line-height: 1.7;
    animation: fadeInUp 0.7s ease-out 0.2s both;
}

.hero-actions {
    display: flex;
    flex-wrap: wrap;
    justify-content: center;
    gap: 1rem;
    animation: fadeInUp 0.7s ease-out 0.3s both;
}

.btn-hero-primary {
    border-radius: 3rem;
    padding: 0.75rem 2.2rem;
    font-weight: 600;
    font-size: 1rem;
    letter-spacing: 0.02em;
    background: var(--gradient-accent);
    border: none;
    color: #fff;
    box-shadow: 0 6px 28px rgba(108, 140, 255, 0.35);
    transition: var(--transition-smooth);
}

.btn-hero-primary:hover {
    box-shadow: 0 10px 36px rgba(108, 140, 255, 0.5);
    transform: translateY(-2px);
    color: #fff;
}

.btn-hero-outline {
    border-radius: 3rem;
    padding: 0.75rem 2.2rem;
    font-weight: 600;
    font-size: 1rem;
    letter-spacing: 0.02em;
    border: 1.5px solid var(--border-subtle);
    color: var(--text-primary);
    background: transparent;
    transition: var(--transition-smooth);
}

.btn-hero-outline:hover {
    border-color: rgba(255, 255, 255, 0.3);
    background: rgba(255, 255, 255, 0.03);
    color: #fff;
}

.btn-tool-outline {
    border-radius: 3rem;
    padding: 0.75rem 2.2rem;
    font-weight: 600;
    font-size: 1rem;
    letter-spacing: 0.02em;
    border: 1.5px solid rgba(255, 255, 255, 0.3);
    color: var(--text-primary);
    background: transparent;
    transition: var(--transition-smooth);
}

.btn-tool-outline:hover {
    border-color: rgba(108, 140, 255, 0.3);
    background: rgba(255, 255, 255, 0.03);
    color: #fff;
}

/* --- 特色卡片区域 --- */
.features-section {
    position: relative;
    z-index: 1;
    padding: 3rem 0 6rem;
}

.section-label {
    text-align: center;
    font-size: 0.8rem;
    font-weight: 700;
    letter-spacing: 0.08em;
    text-transform: uppercase;
    color: var(--accent-primary);
    margin-bottom: 0.8rem;
}

.section-heading {
    text-align: center;
    font-size: clamp(1.8rem, 3.5vw, 2.4rem);
    font-weight: 800;
    letter-spacing: -0.02em;
    margin-bottom: 3.5rem;
    color: var(--text-primary);
}

.feature-card {
    background: var(--bg-card);
    border: 1px solid var(--border-subtle);
    border-radius: var(--radius-lg);
    padding: 2.2rem 1.8rem;
    height: 100%;
    transition: var(--transition-smooth);
    position: relative;
    overflow: hidden;
    box-shadow: var(--shadow-card);
    animation: fadeInUp 0.6s ease-out both;
}

.feature-card:nth-child(1) {
    animation-delay: 0.05s;
}

.feature-card:nth-child(2) {
    animation-delay: 0.15s;
}

.feature-card:nth-child(3) {
    animation-delay: 0.25s;
}

.feature-card:nth-child(4) {
    animation-delay: 0.35s;
}

.feature-card::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    height: 2px;
    background: var(--gradient-card-border);
    opacity: 0;
    transition: opacity 0.4s ease;
}

.feature-card:hover {
    background: var(--bg-card-hover);
    border-color: rgba(108, 140, 255, 0.3);
    transform: translateY(-6px);
    box-shadow: var(--shadow-card), var(--shadow-glow);
}

.feature-card:hover .btn-tool-outline {
    border-color: rgba(108, 140, 255, 0.3);
    background: rgba(255, 255, 255, 0.03);
    color: #fff;
}

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

.feature-icon-wrap {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    width: 54px;
    height: 54px;
    border-radius: var(--radius-sm);
    background: rgba(108, 140, 255, 0.1);
    margin-bottom: 1.4rem;
    transition: var(--transition-smooth);
}

.feature-card:hover .feature-icon-wrap {
    background: rgba(108, 140, 255, 0.18);
    box-shadow: 0 0 28px rgba(108, 140, 255, 0.2);
}

.feature-icon-wrap i {
    font-size: 1.6rem;
    color: var(--accent-primary);
    transition: var(--transition-smooth);
}

.feature-card:hover .feature-icon-wrap i {
    color: #b4c6ff;
}

.feature-card h5 {
    font-weight: 700;
    font-size: 1.1rem;
    letter-spacing: -0.01em;
    margin-bottom: 0.6rem;
    color: var(--text-primary);
}

.feature-card p {
    color: var(--text-secondary);
    font-size: 0.9rem;
    line-height: 1.65;
    margin-bottom: 0;
}

.tool-card {
    background: var(--bg-card);
    border: 1px solid var(--border-subtle);
    border-radius: var(--radius-lg);
    padding: 3rem 2.5rem;
    text-align: center;
    box-shadow: var(--shadow-card);
    position: relative;
    overflow: hidden;
    transition: var(--transition-smooth);
    animation: fadeInUp 0.7s ease-out 0.4s both;
}

.tool-card:hover {
    border-color: rgba(167, 139, 250, 0.35);
    box-shadow: var(--shadow-card), 0 0 80px rgba(167, 139, 250, 0.06);
}

.text-primary2 {
    color: var(--primary-color);
}

.text-primary3 {
    color: var(--accent-primary);
}

.text-light2 {
    color: var(--light-color);
}

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

body.zh .retooldiv {
    max-width: 400px;
}

/* --- 动画 --- */
@keyframes fadeInUp {
    from {
        opacity: 0;
        transform: translateY(28px);
    }

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

/* --- 响应式微调 --- */
@media (max-width: 768px) {
    .hero-section {
        padding: 5rem 0 3rem;
    }

    .feature-card {
        padding: 1.6rem 1.3rem;
    }

    .principle-card {
        padding: 2rem 1.5rem;
    }

    .principle-text {
        font-size: 1.2rem;
    }

    .mission-card {
        padding: 2rem 1.5rem;
    }
}