/* ============================================================
   隐捕 StealthCap 官网样式 —— 深色主题（Material Design 3）
   基线 #121212 + 白色叠加层级
   ============================================================ */

:root {
    /* ===== 背景层级（海拔） ===== */
    --bg:            #121212;
    --surface-1:     #1E1E1E;  /* 1dp = 5% 白 */
    --surface-2:     #252526;  /* 2dp = 7% 白 */
    --surface-3:     #2D2D2D;  /* 4dp = 9% 白 */
    --border:        #333333;

    /* ===== 文本 ===== */
    --text-primary:   #E0E0E0;
    --text-secondary: #AAAAAA;
    --text-disabled:  #666666;

    /* ===== 品牌/状态色 ===== */
    --armed:    #E53935;  /* 布控 红 */
    --idle:     #757575;  /* 休眠 灰 */
    --accent:   #2196F3;  /* CTA 蓝 */
    --success:  #4CAF50;
    --warning:  #FF9800;
    --error:    #CF6679;
    --danger:   #E53935;

    /* ===== 间距 ===== */
    --container-max: 1120px;
    --section-py: 96px;
    --section-px: 24px;
}

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

html {
    scroll-behavior: smooth;
}

body {
    font-family: "Segoe UI", -apple-system, BlinkMacSystemFont, "Helvetica Neue",
                 "PingFang SC", "Microsoft YaHei", sans-serif;
    background: var(--bg);
    color: var(--text-primary);
    line-height: 1.6;
    -webkit-font-smoothing: antialiased;
    -moz-osx-font-smoothing: grayscale;
    overflow-x: hidden;
}

a {
    color: var(--accent);
    text-decoration: none;
    transition: color 0.2s;
}

a:hover {
    color: #64B5F6;
}

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

.container {
    max-width: var(--container-max);
    margin: 0 auto;
    padding: 0 var(--section-px);
}

/* ===== 通用按钮 ===== */
.btn {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    gap: 8px;
    padding: 12px 28px;
    border-radius: 6px;
    font-size: 15px;
    font-weight: 600;
    border: none;
    cursor: pointer;
    transition: all 0.2s ease;
    text-decoration: none;
    white-space: nowrap;
}

.btn-primary {
    background: var(--accent);
    color: #fff;
    box-shadow: 0 2px 8px rgba(33, 150, 243, 0.35);
}

.btn-primary:hover {
    background: #1E88E5;
    box-shadow: 0 4px 16px rgba(33, 150, 243, 0.5);
    transform: translateY(-1px);
    color: #fff;
}

.btn-secondary {
    background: var(--surface-2);
    color: var(--text-primary);
    border: 1px solid var(--border);
}

.btn-secondary:hover {
    background: var(--surface-3);
    border-color: var(--text-secondary);
    color: var(--text-primary);
}

.btn-danger {
    background: var(--danger);
    color: #fff;
}

.btn-outline {
    background: transparent;
    color: var(--text-primary);
    border: 1px solid var(--border);
}

.btn-outline:hover {
    border-color: var(--accent);
    color: var(--accent);
}

/* ===== 通用 Section ===== */
section {
    padding: var(--section-py) 0;
}

.section-header {
    text-align: center;
    margin-bottom: 64px;
}

.section-header h2 {
    font-size: 34px;
    font-weight: 700;
    letter-spacing: -0.5px;
    margin-bottom: 12px;
}

.section-header p {
    font-size: 17px;
    color: var(--text-secondary);
    max-width: 640px;
    margin: 0 auto;
}

/* ===== 语言切换 ===== */
.lang-switch {
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    z-index: 1000;
    background: rgba(18, 18, 18, 0.85);
    backdrop-filter: blur(12px);
    -webkit-backdrop-filter: blur(12px);
    border-bottom: 1px solid var(--border);
    transition: transform 0.3s;
}

.lang-switch-inner {
    display: flex;
    justify-content: flex-end;
    align-items: center;
    padding: 8px var(--section-px);
    max-width: var(--container-max);
    margin: 0 auto;
    gap: 8px;
}

.lang-btn {
    background: transparent;
    border: 1px solid var(--border);
    color: var(--text-secondary);
    padding: 4px 14px;
    border-radius: 4px;
    font-size: 13px;
    cursor: pointer;
    transition: all 0.2s;
    font-family: inherit;
}

.lang-btn:hover {
    border-color: var(--accent);
    color: var(--text-primary);
}

.lang-btn.active {
    background: var(--accent);
    border-color: var(--accent);
    color: #fff;
}

/* ===== 导航栏 ===== */
.navbar {
    position: fixed;
    top: 41px;
    left: 0;
    right: 0;
    z-index: 999;
    background: rgba(18, 18, 18, 0.85);
    backdrop-filter: blur(12px);
    -webkit-backdrop-filter: blur(12px);
    border-bottom: 1px solid var(--border);
    transition: transform 0.3s;
}

.navbar-inner {
    display: flex;
    align-items: center;
    justify-content: space-between;
    padding: 14px var(--section-px);
    max-width: var(--container-max);
    margin: 0 auto;
}

.navbar-brand {
    display: flex;
    align-items: center;
    gap: 10px;
    font-size: 20px;
    font-weight: 700;
    color: var(--text-primary);
    text-decoration: none;
}

.brand-logo {
    width: 32px;
    height: 32px;
    border-radius: 8px;
    background: linear-gradient(135deg, var(--accent), #1565C0);
    display: flex;
    align-items: center;
    justify-content: center;
    color: #fff;
    font-weight: 800;
    font-size: 16px;
    box-shadow: 0 2px 8px rgba(33, 150, 243, 0.35);
}

.brand-cn {
    font-size: 19px;
}

.brand-en {
    font-size: 15px;
    color: var(--text-secondary);
    font-weight: 500;
    padding-left: 10px;
    border-left: 1px solid var(--border);
}

.navbar-links {
    display: flex;
    align-items: center;
    gap: 32px;
}

.navbar-links a {
    color: var(--text-secondary);
    font-size: 15px;
    font-weight: 500;
    transition: color 0.2s;
}

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

.navbar-cta {
    background: var(--accent);
    color: #fff !important;
    padding: 8px 20px;
    border-radius: 6px;
    font-weight: 600;
}

.navbar-cta:hover {
    background: #1E88E5;
    color: #fff !important;
}

/* ===== Hero ===== */
.hero {
    padding: 180px 0 120px;
    position: relative;
    overflow: hidden;
}

.hero::before {
    content: "";
    position: absolute;
    top: -200px;
    right: -200px;
    width: 600px;
    height: 600px;
    border-radius: 50%;
    background: radial-gradient(circle, rgba(33, 150, 243, 0.12) 0%, transparent 70%);
    pointer-events: none;
}

.hero::after {
    content: "";
    position: absolute;
    bottom: -200px;
    left: -200px;
    width: 500px;
    height: 500px;
    border-radius: 50%;
    background: radial-gradient(circle, rgba(229, 57, 53, 0.08) 0%, transparent 70%);
    pointer-events: none;
}

.hero-inner {
    display: grid;
    grid-template-columns: 1.1fr 0.9fr;
    gap: 64px;
    align-items: center;
    position: relative;
    z-index: 1;
}

.hero-badge {
    display: inline-flex;
    align-items: center;
    gap: 8px;
    background: var(--surface-1);
    border: 1px solid var(--border);
    color: var(--success);
    padding: 8px 16px;
    border-radius: 100px;
    font-size: 14px;
    font-weight: 500;
    margin-bottom: 28px;
}

.hero h1 {
    font-size: 52px;
    font-weight: 800;
    line-height: 1.15;
    letter-spacing: -1.5px;
    margin-bottom: 24px;
}

.hero-desc {
    font-size: 18px;
    color: var(--text-secondary);
    line-height: 1.75;
    margin-bottom: 36px;
    max-width: 560px;
}

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

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

.hero-window {
    background: var(--surface-1);
    border: 1px solid var(--border);
    border-radius: 12px;
    overflow: hidden;
    box-shadow: 0 24px 64px rgba(0, 0, 0, 0.5);
}

.hero-window-bar {
    background: var(--surface-2);
    padding: 12px 16px;
    display: flex;
    align-items: center;
    gap: 8px;
    border-bottom: 1px solid var(--border);
}

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

.hero-dot.red    { background: #FF5F57; }
.hero-dot.yellow { background: #FEBC2E; }
.hero-dot.green  { background: #28C840; }

.hero-window-title {
    margin-left: 12px;
    font-size: 13px;
    color: var(--text-secondary);
}

.hero-window-body {
    padding: 24px;
}

/* 状态指示器 */
.status-indicator {
    display: flex;
    align-items: center;
    gap: 12px;
    padding: 16px;
    background: var(--surface-2);
    border-radius: 8px;
    margin-bottom: 20px;
}

.status-dot {
    width: 14px;
    height: 14px;
    border-radius: 50%;
    background: var(--armed);
    box-shadow: 0 0 0 4px rgba(229, 57, 53, 0.2);
    animation: pulse 2s infinite;
}

@keyframes pulse {
    0%, 100% { box-shadow: 0 0 0 4px rgba(229, 57, 53, 0.2); }
    50%      { box-shadow: 0 0 0 8px rgba(229, 57, 53, 0.05); }
}

.status-text {
    font-size: 15px;
    font-weight: 600;
}

.status-sub {
    font-size: 13px;
    color: var(--text-secondary);
}

/* 截图网格 */
.capture-grid {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 10px;
}

.capture-thumb {
    aspect-ratio: 16 / 10;
    background: var(--surface-2);
    border-radius: 6px;
    border: 1px solid var(--border);
    position: relative;
    overflow: hidden;
}

.capture-thumb::before {
    content: "";
    position: absolute;
    inset: 0;
    background: linear-gradient(135deg, var(--surface-2), var(--surface-3));
}

.capture-thumb .cap-time {
    position: absolute;
    bottom: 6px;
    left: 8px;
    font-size: 11px;
    color: var(--text-secondary);
    font-variant-numeric: tabular-nums;
}

.capture-thumb .cap-label {
    position: absolute;
    top: 6px;
    right: 8px;
    font-size: 10px;
    color: var(--text-disabled);
}

/* ===== Features ===== */
.features-grid {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 24px;
}

.feature-card {
    background: var(--surface-1);
    border: 1px solid var(--border);
    border-radius: 12px;
    padding: 32px 28px;
    transition: all 0.3s ease;
}

.feature-card:hover {
    transform: translateY(-4px);
    border-color: var(--accent);
    box-shadow: 0 12px 32px rgba(0, 0, 0, 0.4);
}

.feature-icon {
    width: 52px;
    height: 52px;
    border-radius: 12px;
    background: rgba(33, 150, 243, 0.12);
    color: var(--accent);
    display: flex;
    align-items: center;
    justify-content: center;
    margin-bottom: 20px;
}

.feature-icon svg {
    width: 26px;
    height: 26px;
}

.feature-card h3 {
    font-size: 19px;
    font-weight: 700;
    margin-bottom: 10px;
}

.feature-card p {
    font-size: 15px;
    color: var(--text-secondary);
    line-height: 1.65;
}

/* ===== Security ===== */
.security-section {
    background: linear-gradient(180deg, var(--bg) 0%, var(--surface-1) 100%);
    border-top: 1px solid var(--border);
    border-bottom: 1px solid var(--border);
}

.security-grid {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 32px;
}

.security-card {
    text-align: center;
    padding: 8px;
}

.security-icon {
    width: 64px;
    height: 64px;
    border-radius: 50%;
    background: var(--surface-2);
    border: 1px solid var(--border);
    display: flex;
    align-items: center;
    justify-content: center;
    margin: 0 auto 20px;
    color: var(--success);
}

.security-icon svg {
    width: 28px;
    height: 28px;
}

.security-card h3 {
    font-size: 19px;
    font-weight: 700;
    margin-bottom: 12px;
}

.security-card p {
    font-size: 15px;
    color: var(--text-secondary);
    line-height: 1.7;
}

/* ===== Scenarios ===== */
.scenarios-grid {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 24px;
}

.scenario-card {
    background: var(--surface-1);
    border: 1px solid var(--border);
    border-radius: 12px;
    padding: 36px 28px;
    text-align: center;
    transition: all 0.3s ease;
}

.scenario-card:hover {
    border-color: var(--accent);
    background: var(--surface-2);
}

.scenario-icon {
    font-size: 48px;
    margin-bottom: 20px;
    display: block;
}

.scenario-card h3 {
    font-size: 20px;
    font-weight: 700;
    margin-bottom: 12px;
}

.scenario-card p {
    font-size: 15px;
    color: var(--text-secondary);
    line-height: 1.7;
}

/* ===== Pricing ===== */
.pricing-grid {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 24px;
    align-items: stretch;
}

.pricing-card {
    background: var(--surface-1);
    border: 1px solid var(--border);
    border-radius: 12px;
    padding: 36px 32px;
    display: flex;
    flex-direction: column;
    position: relative;
    transition: all 0.3s ease;
}

.pricing-card:hover {
    transform: translateY(-4px);
    box-shadow: 0 16px 40px rgba(0, 0, 0, 0.4);
}

.pricing-card.highlight {
    border: 2px solid var(--accent);
    background: linear-gradient(180deg, var(--surface-2) 0%, var(--surface-1) 100%);
}

.pricing-badge {
    position: absolute;
    top: -12px;
    left: 50%;
    transform: translateX(-50%);
    background: var(--accent);
    color: #fff;
    padding: 4px 16px;
    border-radius: 100px;
    font-size: 12px;
    font-weight: 600;
    white-space: nowrap;
}

.pricing-name {
    font-size: 18px;
    font-weight: 600;
    color: var(--text-secondary);
    margin-bottom: 8px;
}

.pricing-price {
    font-size: 44px;
    font-weight: 800;
    letter-spacing: -1.5px;
    margin-bottom: 4px;
}

.pricing-unit {
    font-size: 14px;
    color: var(--text-secondary);
    margin-bottom: 28px;
}

.pricing-features {
    list-style: none;
    margin-bottom: 32px;
    flex-grow: 1;
}

.pricing-features li {
    font-size: 15px;
    color: var(--text-secondary);
    padding: 8px 0;
    padding-left: 26px;
    position: relative;
}

.pricing-features li::before {
    content: "";
    position: absolute;
    left: 0;
    top: 14px;
    width: 14px;
    height: 14px;
    background: var(--accent);
    -webkit-mask: url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' viewBox='0 0 24 24' fill='none' stroke='black' stroke-width='3' stroke-linecap='round' stroke-linejoin='round'%3E%3Cpolyline points='20 6 9 17 4 12'%3E%3C/polyline%3E%3C/svg%3E") no-repeat center / contain;
            mask: url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' viewBox='0 0 24 24' fill='none' stroke='black' stroke-width='3' stroke-linecap='round' stroke-linejoin='round'%3E%3Cpolyline points='20 6 9 17 4 12'%3E%3C/polyline%3E%3C/svg%3E") no-repeat center / contain;
}

.pricing-card .btn {
    width: 100%;
}

/* ===== FAQ ===== */
.faq-list {
    max-width: 820px;
    margin: 0 auto;
}

.faq-item {
    background: var(--surface-1);
    border: 1px solid var(--border);
    border-radius: 10px;
    margin-bottom: 12px;
    overflow: hidden;
}

.faq-question {
    width: 100%;
    background: transparent;
    border: none;
    padding: 20px 24px;
    display: flex;
    align-items: center;
    justify-content: space-between;
    gap: 16px;
    font-size: 16px;
    font-weight: 600;
    color: var(--text-primary);
    cursor: pointer;
    text-align: left;
    font-family: inherit;
    transition: background 0.2s;
}

.faq-question:hover {
    background: var(--surface-2);
}

.faq-question .faq-icon {
    flex-shrink: 0;
    width: 20px;
    height: 20px;
    color: var(--text-secondary);
    transition: transform 0.3s;
}

.faq-item.open .faq-question .faq-icon {
    transform: rotate(180deg);
}

.faq-answer {
    max-height: 0;
    overflow: hidden;
    transition: max-height 0.3s ease;
}

.faq-answer-inner {
    padding: 0 24px 20px;
    font-size: 15px;
    color: var(--text-secondary);
    line-height: 1.75;
}

/* ===== CTA ===== */
.cta-section {
    background: var(--surface-1);
    border-top: 1px solid var(--border);
    text-align: center;
}

.cta-section h2 {
    font-size: 34px;
    font-weight: 700;
    margin-bottom: 12px;
}

.cta-section p {
    font-size: 17px;
    color: var(--text-secondary);
    margin-bottom: 32px;
}

/* ===== Footer ===== */
.footer {
    background: var(--bg);
    border-top: 1px solid var(--border);
    padding: 40px 0;
}

.footer-inner {
    display: flex;
    justify-content: space-between;
    align-items: center;
    flex-wrap: wrap;
    gap: 16px;
}

.footer-brand {
    display: flex;
    align-items: center;
    gap: 10px;
    font-size: 15px;
    font-weight: 600;
}

.footer-brand .brand-logo {
    width: 28px;
    height: 28px;
    font-size: 14px;
}

.footer-links {
    display: flex;
    gap: 24px;
}

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

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

.footer-copy {
    font-size: 13px;
    color: var(--text-disabled);
    width: 100%;
    text-align: center;
    margin-top: 8px;
}

/* ===== 响应式 ===== */
@media (max-width: 960px) {
    .hero-inner {
        grid-template-columns: 1fr;
        gap: 48px;
    }

    .hero h1 {
        font-size: 38px;
    }

    .hero-visual {
        order: -1;
    }

    .features-grid,
    .security-grid,
    .scenarios-grid,
    .pricing-grid {
        grid-template-columns: 1fr;
    }

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

    section {
        padding: 64px 0;
    }

    .navbar-links {
        display: none;
    }

    .brand-en {
        display: none;
    }
}

@media (max-width: 560px) {
    .hero h1 {
        font-size: 30px;
    }

    .hero-desc {
        font-size: 16px;
    }

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

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

    .cta-section h2 {
        font-size: 26px;
    }

    .pricing-price {
        font-size: 36px;
    }
}