/* Custom Styles */

.bg-gradient-primary {
    background: linear-gradient(45deg, #0d6efd, #0dcaf0) !important;
}

.bg-gradient-warning {
    background: linear-gradient(45deg, #ffc107, #f1c40f) !important;
}

.bg-gradient-info {
    background: linear-gradient(45deg, #0dcaf0, #00d2ff) !important;
}

.feature-card {
    transition: transform 0.3s cubic-bezier(0.34, 1.56, 0.64, 1), box-shadow 0.3s ease;
    border-radius: 1.5rem;
    height: 100%;
    border: 1px solid rgba(0,0,0,0.05);
}

.feature-card:hover {
    transform: translateY(-12px);
    box-shadow: 0 1rem 3rem rgba(0,0,0,0.1) !important;
    background: #fff;
}

.feature-icon {
    width: 80px;
    height: 80px;
    transition: transform 0.3s ease;
}

.feature-card:hover .feature-icon {
    transform: scale(1.1) rotate(5deg);
}

.feature-icon-wrapper {
    position: relative;
    display: inline-block;
}

.rounded-4 {
    border-radius: 1.25rem !important;
}

html {
    scroll-behavior: smooth;
}

#typed-headline {
    display: inline;
    vertical-align: baseline;
    white-space: pre-wrap;
}

.typed-cursor {
    font-size: 0.95em;
    color: var(--accent);
    opacity: 1;
    display: inline-block;
    vertical-align: baseline;
    margin-left: 0.1rem;
    font-weight: 200;
    line-height: 1;
    transform: translateZ(0);
    backface-visibility: hidden;
}

h1, h2, h3, h4, h5, h6 {
    letter-spacing: -0.02em;
}

.text-muted {
    font-size: 0.95rem;
    line-height: 1.6;
}

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

/* ═══ Theme Variables ═══ */
:root {
    --font: -apple-system, BlinkMacSystemFont, 'SF Pro Display', 'SF Pro Text', 'Helvetica Neue', 'Microsoft YaHei UI', system-ui, sans-serif;
    --font-mono: 'SF Mono', 'Fira Code', 'Cascadia Code', Menlo, monospace;
    --radius: 8px;
    --radius-sm: 4px;
    --radius-lg: 12px;
    --radius-xl: 16px;
    --transition: 0.25s cubic-bezier(0.4, 0, 0.2, 1);
    --shadow-sm: 0 1px 2px rgba(0,0,0,0.04);
    --shadow: 0 2px 8px rgba(0,0,0,0.06);
    --shadow-md: 0 4px 16px rgba(0,0,0,0.08);
    --shadow-lg: 0 8px 32px rgba(0,0,0,0.12);
    --max-w: 1140px;
    --max-w-lg: 1200px;
    /* Accent */
    --accent: #0d6efd;
    --accent-hover: #0b5ed7;
    --accent-light: rgba(13,110,253,0.1);
    --success: #198754;
    --warning: #ffc107;
    --danger: #dc3545;
}

/* ═══ Light Theme (default) ═══ */
:root, [data-theme="light"] {
    --bg: #ffffff;
    --bg-secondary: #f5f5f7;
    --bg-tertiary: #fbfbfd;
    --bg-elevated: #ffffff;
    --bg-blur: rgba(255,255,255,0.72);
    --border: rgba(0,0,0,0.08);
    --border-strong: rgba(0,0,0,0.14);
    --text-primary: #1d1d1f;
    --text-secondary: #6e6e73;
    --text-tertiary: #86868b;
    --text-quaternary: #aeaeb2;
    --card-bg: #ffffff;
    --card-border: rgba(0,0,0,0.06);
    --card-shadow: 0 2px 12px rgba(0,0,0,0.06);
    --input-bg: #f5f5f7;
    --input-border: rgba(0,0,0,0.1);
    --input-focus: var(--accent);
    --nav-bg: rgba(255,255,255,0.72);
    --badge-bg: #f5f5f7;
    --code-bg: #f5f5f7;
    --hover-bg: rgba(0,0,0,0.03);
    --overlay: rgba(0,0,0,0.4);
    --glow: rgba(13,110,253,0.15);
    --dot-color: rgba(0,0,0,0.04);
    --mesh-1: rgba(0,113,227,0.06);
    --mesh-2: rgba(88,86,214,0.05);
    --mesh-3: rgba(52,199,89,0.04);
    --noise-opacity: 0.03;
    --section-fade: linear-gradient(180deg, var(--bg) 0%, var(--bg-secondary) 100%);
}

/* ═══ Dark Theme ═══ */
[data-theme="dark"] {
    --bg: #000000;
    --bg-secondary: #1c1c1e;
    --bg-tertiary: #0a0a0a;
    --bg-elevated: #1c1c1e;
    --bg-blur: rgba(28,28,30,0.72);
    --border: rgba(255,255,255,0.08);
    --border-strong: rgba(255,255,255,0.14);
    --text-primary: #f5f5f7;
    --text-secondary: #a1a1a6;
    --text-tertiary: #86868b;
    --text-quaternary: #636366;
    --card-bg: #1c1c1e;
    --card-border: rgba(255,255,255,0.06);
    --card-shadow: 0 2px 12px rgba(0,0,0,0.3);
    --input-bg: #2c2c2e;
    --input-border: rgba(255,255,255,0.1);
    --input-focus: var(--accent);
    --nav-bg: rgba(28,28,30,0.72);
    --badge-bg: #2c2c2e;
    --code-bg: #2c2c2e;
    --hover-bg: rgba(255,255,255,0.04);
    --overlay: rgba(0,0,0,0.6);
    --glow: rgba(13,110,253,0.2);
    --dot-color: rgba(255,255,255,0.03);
    --mesh-1: rgba(0,113,227,0.08);
    --mesh-2: rgba(88,86,214,0.06);
    --mesh-3: rgba(52,199,89,0.05);
    --noise-opacity: 0.015;
    --section-fade: linear-gradient(180deg, var(--bg) 0%, var(--bg-secondary) 100%);
    --shadow-sm: 0 1px 2px rgba(0,0,0,0.2);
    --shadow: 0 2px 8px rgba(0,0,0,0.25);
    --shadow-md: 0 4px 16px rgba(0,0,0,0.3);
    --shadow-lg: 0 8px 32px rgba(0,0,0,0.4);
}

/* Auto system preference */
@media (prefers-color-scheme: dark) {
    :root:not([data-theme="light"]) {
        --dot-color: rgba(255,255,255,0.03);
        --mesh-1: rgba(0,113,227,0.08);
        --mesh-2: rgba(88,86,214,0.06);
        --mesh-3: rgba(52,199,89,0.05);
        --noise-opacity: 0.015;
        --section-fade: linear-gradient(180deg, var(--bg) 0%, var(--bg-secondary) 100%);
        --bg: #000000;
        --bg-secondary: #1c1c1e;
        --bg-tertiary: #0a0a0a;
        --bg-elevated: #1c1c1e;
        --bg-blur: rgba(28,28,30,0.72);
        --border: rgba(255,255,255,0.08);
        --border-strong: rgba(255,255,255,0.14);
        --text-primary: #f5f5f7;
        --text-secondary: #a1a1a6;
        --text-tertiary: #86868b;
        --text-quaternary: #636366;
        --card-bg: #1c1c1e;
        --card-border: rgba(255,255,255,0.06);
        --card-shadow: 0 2px 12px rgba(0,0,0,0.3);
        --input-bg: #2c2c2e;
        --input-border: rgba(255,255,255,0.1);
        --input-focus: var(--accent);
        --nav-bg: rgba(28,28,30,0.72);
        --badge-bg: #2c2c2e;
        --code-bg: #2c2c2e;
        --hover-bg: rgba(255,255,255,0.04);
        --overlay: rgba(0,0,0,0.6);
        --glow: rgba(0,113,227,0.2);
        --shadow-sm: 0 1px 2px rgba(0,0,0,0.2);
        --shadow: 0 2px 8px rgba(0,0,0,0.25);
        --shadow-md: 0 4px 16px rgba(0,0,0,0.3);
        --shadow-lg: 0 8px 32px rgba(0,0,0,0.4);
    }
}

/* ═══ Base ═══ */
/* Subtle dot grid background */
body.ShieldShell-mode::before {
    content: '';
    position: fixed; inset: 0; z-index: -2;
    background-image: radial-gradient(circle, var(--dot-color) 1px, transparent 1px);
    background-size: 24px 24px;
    pointer-events: none;
    transition: background-image 0.4s ease;
}
/* Noise texture overlay */
body.ShieldShell-mode::after {
    content: '';
    position: fixed; inset: 0; z-index: -1;
    opacity: var(--noise-opacity);
    background-image: url("data:image/svg+xml,%3Csvg viewBox='0 0 256 256' xmlns='http://www.w3.org/2000/svg'%3E%3Cfilter id='n'%3E%3CfeTurbulence type='fractalNoise' baseFrequency='0.9' numOctaves='4' stitchTiles='stitch'/%3E%3C/filter%3E%3Crect width='100%25' height='100%25' filter='url(%23n)'/%3E%3C/svg%3E");
    pointer-events: none;
    transition: opacity 0.4s ease;
}
body.ShieldShell-mode {
    font-family: var(--font);
    background: var(--bg);
    color: var(--text-primary);
    transition: background 0.4s ease, color 0.3s ease;
}

/* ═══ Typography ═══ */
.t-headline { 
    font-size: 3.5rem; 
    font-weight: 800; 
    letter-spacing: -0.025em; 
    line-height: 1.2; 
    color: var(--text-primary); 
    min-height: 2.4em;
    display: block;
    position: relative;
    -webkit-font-smoothing: antialiased;
}
.t-title { font-size: 2.25rem; font-weight: 700; letter-spacing: -0.02em; line-height: 1.2; color: var(--text-primary); }
.t-subtitle { font-size: 1.5rem; font-weight: 600; letter-spacing: -0.01em; line-height: 1.3; }
.t-body-lg { font-size: 1.125rem; line-height: 1.5; color: var(--text-secondary); }
.t-body { font-size: 0.9375rem; line-height: 1.5; color: var(--text-secondary); }
.t-caption { font-size: 0.8125rem; line-height: 1.4; color: var(--text-tertiary); }
.t-small { font-size: 0.75rem; color: var(--text-tertiary); }
.t-center { text-align: center; }

/* ═══ Layout ═══ */
.container-ShieldShell { max-width: var(--max-w); margin: 0 auto; padding: 0 1.5rem; }
.section-ShieldShell { padding: 5rem 0; position: relative; }
.section-alt { background: var(--bg-secondary); transition: background 0.4s ease; }

/* ═══ Hero ═══ */
.hero-ShieldShell { 
    min-height: 80vh; 
    display: flex; 
    flex-direction: column; 
    align-items: center; 
    justify-content: center; 
    text-align: center; 
    padding: 6rem 1.5rem 4rem; 
    position: relative; 
    max-width: var(--max-w-lg);
    margin: 0 auto;
}
.hero-ShieldShell::before { content:''; position:absolute; top:-30%; left:50%; transform:translateX(-50%); width:700px; height:700px; background:radial-gradient(circle, var(--glow) 0%, transparent 70%); pointer-events:none; }
.hero-ShieldShell::after { content:''; position:absolute; bottom:-20%; right:-15%; width:500px; height:500px; background:radial-gradient(circle, var(--mesh-2) 0%, transparent 70%); pointer-events:none; filter:blur(40px); }

.hero-inner { position: relative; z-index: 1; max-width: 680px; width: 100%; }
.hero-ShieldShell h1 { margin-bottom: 1rem; }
.hero-desc { max-width: 520px; margin: 0 auto 2.5rem; }
.hero-actions { display: flex; gap: 1rem; justify-content: center; flex-wrap: wrap; }
.hero-metrics { display: flex; gap: 3rem; justify-content: center; margin-top: 4rem; padding-top: 2.5rem; border-top: 1px solid var(--border); }
.metric-val { font-size: 2rem; font-weight: 700; color: var(--accent); }
.metric-label { font-size: 0.8125rem; color: var(--text-tertiary); margin-top: 0.15rem; }

/* ═══ Hero Image ═══ */
.hero-figure {
    margin-top: 3rem;
    position: relative;
    z-index: 1;
    perspective: 1200px;
    width: 100%;
}
.hero-image-wrapper {
    max-width: 800px;
    margin: 0 auto;
    border-radius: var(--radius-xl);
    overflow: hidden;
    box-shadow: var(--shadow-lg);
    border: 1px solid var(--border);
    background: var(--bg-elevated);
    transform: rotateX(5deg) translateY(0);
    transition: transform 0.8s cubic-bezier(0.2, 0.8, 0.2, 1);
}

/* Desktop layout adjustment */
@media (min-width: 992px) {
    .hero-ShieldShell {
        flex-direction: row;
        text-align: left;
        gap: 4rem;
        padding: 8rem 2rem;
        align-items: center;
        max-width: 1400px;
        margin: 0 auto;
    }
    .hero-inner {
        flex: 1;
        max-width: 600px;
    }
    .hero-figure {
        flex: 1.4;
        margin-top: 0;
        display: flex;
        justify-content: center;
        perspective: 2000px;
    }
    .hero-image-wrapper {
        width: 100%;
        max-width: 850px;
        transform: rotateX(6deg) rotateY(-12deg) rotateZ(1deg);
        border-radius: var(--radius-lg);
        box-shadow: 30px 30px 80px rgba(0,0,0,0.25);
        transition: transform 0.6s cubic-bezier(0.16, 1, 0.3, 1);
    }
    .hero-image {
        width: 100%;
        height: auto;
        display: block;
    }
    .hero-figure:hover .hero-image-wrapper {
        transform: rotateX(0deg) rotateY(0deg) rotateZ(0deg) translateY(-20px) scale(1.02);
    }
}

 .hero-image {
    width: 100%;
    height: auto;
    display: block;
    object-fit: cover;
}

/* ═══ Feature cards ═══ */
.feat { text-align: center; }
.feat-icon { 
    width: 64px; 
    height: 64px; 
    border-radius: var(--radius-lg); 
    display: flex; 
    align-items: center; 
    justify-content: center; 
    font-size: 1.8rem; 
    margin: 0 auto 1.25rem; 
    background: var(--accent-light);
    transition: transform 0.3s cubic-bezier(0.34, 1.56, 0.64, 1);
}
.card-ShieldShell.feat:hover .feat-icon {
    transform: scale(1.1) rotate(5deg);
}
.feat h3 { font-size: 1.25rem; font-weight: 700; margin-bottom: 0.75rem; color: var(--text-primary); }
.feat p { font-size: 0.9375rem; color: var(--text-secondary); line-height: 1.6; }

/* ═══ Steps ═══ */
.steps { display: flex; gap: 2rem; }
.step { flex: 1; text-align: center; }
.step-n { width: 52px; height: 52px; border-radius: 50%; background: var(--accent); color: #fff; font-size: 1.25rem; font-weight: 700; display: flex; align-items: center; justify-content: center; margin: 0 auto 1rem; }
.step h3 { font-size: 1.0625rem; font-weight: 600; margin-bottom: 0.35rem; }
.step p { font-size: 0.875rem; color: var(--text-secondary); }

/* ═══ Levels ═══ */
.lvl { text-align: center; position: relative; }
.lvl-name { font-size: 1.125rem; font-weight: 700; margin-bottom: 0.25rem; }
.lvl-desc { font-size: 0.8125rem; color: var(--text-secondary); margin-bottom: 1rem; }
.lvl ul { text-align: left; font-size: 0.8125rem; list-style: none; padding: 0; }
.lvl li { padding: 0.3rem 0; color: var(--text-secondary); }
.lvl li::before { content: '✓'; color: var(--success); font-weight: 600; margin-right: 0.5rem; }
.lvl.recommended { border-color: var(--accent); box-shadow: 0 0 30px var(--glow); }
.lvl.recommended::after { content: '推荐'; position: absolute; top: -11px; left: 50%; transform: translateX(-50%); background: var(--accent); color: #fff; font-size: 0.6875rem; font-weight: 600; padding: 0.15rem 0.75rem; border-radius: 10px; }

/* ═══ Checks grid ═══ */
.check-item { text-align: center; }
.check-icon { 
    width: 44px; 
    height: 44px; 
    border-radius: 12px; 
    display: flex; 
    align-items: center; 
    justify-content: center; 
    font-size: 1.25rem; 
    margin: 0 auto 0.75rem; 
    background: var(--bg-secondary);
    border: 1px solid var(--border);
    color: var(--accent);
    transition: all 0.2s ease;
}
.check-item:hover .check-icon {
    background: var(--accent);
    color: #fff;
    transform: translateY(-2px);
    box-shadow: 0 4px 12px var(--glow);
}
.check-item h4 { font-size: 0.875rem; font-weight: 600; margin-bottom: 0.15rem; }
.check-item p { font-size: 0.75rem; color: var(--text-tertiary); }

/* ═══ CTA ═══ */
.cta-ShieldShell { text-align: center; position: relative; padding: 5rem 0; }
.cta-ShieldShell::before { content:''; position:absolute; bottom:0; left:50%; transform:translateX(-50%); width:500px; height:350px; background:radial-gradient(circle, var(--glow) 0%, transparent 70%); pointer-events:none; }
.cta-ShieldShell h2, .cta-ShieldShell p, .cta-ShieldShell .hero-actions { position: relative; }

/* ═══ Tech comparison ═══ */
.compare-table { width:100%; border-collapse:collapse; font-size:0.875rem; }
.compare-table th { text-align:left; padding:0.75rem 1rem; color:var(--text-tertiary); font-weight:600; font-size:0.75rem; text-transform:uppercase; letter-spacing:0.04em; border-bottom:1px solid var(--border); }
.compare-table td { padding:0.65rem 1rem; border-bottom:1px solid var(--border); color:var(--text-secondary); }
.compare-table tr:hover td { background:var(--hover-bg); }
.compare-table .yes { color:var(--success); font-weight:600; }
.compare-table .no { color:var(--text-quaternary); }
.compare-table .highlight { color:var(--accent); font-weight:600; }

/* ═══ Trust ═══ */
.trust-grid { display:grid; grid-template-columns:repeat(4,1fr); gap:1.5rem; text-align:center; }
.trust-item .ti-val { font-size:2.5rem; font-weight:800; color:var(--accent); letter-spacing:-0.02em; }
.trust-item .ti-label { font-size:0.8125rem; color:var(--text-tertiary); margin-top:0.2rem; }

/* ═══ FAQ ═══ */
.faq-item { border-bottom:1px solid var(--border); }
.faq-q { padding:1rem 0; cursor:pointer; display:flex; justify-content:space-between; align-items:center; font-weight:600; font-size:0.9375rem; color:var(--text-primary); }
.faq-q:hover { color:var(--accent); }
.faq-q .arrow { transition:transform 0.2s; font-size:0.75rem; color:var(--text-tertiary); }
.faq-item.open .arrow { transform:rotate(180deg); }
.faq-a { max-height:0; overflow:hidden; transition:max-height 0.3s ease; }
.faq-item.open .faq-a { max-height:200px; }
.faq-a p { padding: 0 0 1rem; font-size:0.875rem; color:var(--text-secondary); line-height:1.6; text-align: left; }

/* Mesh bg utility */
.mesh-bg { position: relative; overflow: hidden; }
.mesh-bg::before {
    content: ''; position: absolute; top: -20%; right: -10%; width: 50%; height: 60%;
    background: radial-gradient(ellipse, var(--mesh-1) 0%, transparent 70%);
    pointer-events: none; filter: blur(60px);
}
.mesh-bg::after {
    content: ''; position: absolute; bottom: -20%; left: -10%; width: 40%; height: 50%;
    background: radial-gradient(ellipse, var(--mesh-2) 0%, transparent 70%);
    pointer-events: none; filter: blur(60px);
}

.card-ShieldShell {
    background: var(--card-bg);
    border: 1px solid var(--card-border);
    border-radius: var(--radius-lg);
    box-shadow: var(--card-shadow);
    padding: 1.5rem;
    transition: background 0.4s ease, border-color 0.4s ease, box-shadow 0.3s ease, transform 0.2s ease;
}
.card-ShieldShell:hover { box-shadow: var(--shadow-md); }

.grid-3-ShieldShell { display: grid; grid-template-columns: repeat(3, 1fr); gap: 1.5rem; }
.grid-4-ShieldShell { display: grid; grid-template-columns: repeat(4, 1fr); gap: 1rem; }

@media (max-width: 768px) {
    .t-headline { font-size: 2.25rem; }
    .t-title { font-size: 1.75rem; }
    .hero-metrics { 
        display: grid; 
        grid-template-columns: repeat(2, 1fr); 
        gap: 2rem 1rem; 
        padding-top: 1.5rem;
    }
    .steps { flex-direction: column; }
    .trust-grid { grid-template-columns: repeat(2,1fr); }
    .grid-3-ShieldShell, .grid-4-ShieldShell { grid-template-columns: 1fr; }
    .grid-2-mobile { 
        display: grid; 
        grid-template-columns: repeat(2, 1fr); 
        gap: 1.5rem 1rem; 
    }
}