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

:root {
    --bg: #f9fafb;
    --surface: #ffffff;
    --surface-raised: #ffffff;
    --border: rgba(0,0,0,0.08);
    --border-strong: rgba(0,0,0,0.14);
    --text-primary: #0d1117;
    --text-secondary: #586069;
    --text-muted: #8b949e;
    --accent: #2563eb;
    --accent-hover: #1d4ed8;
    --accent-light: #eff6ff;
    --accent-light-border: #bfdbfe;
    --green: #059669;
    --green-light: #ecfdf5;
    --red: #dc2626;
    --red-light: #fef2f2;
    --shadow-sm: 0 1px 2px rgba(0,0,0,0.05);
    --shadow-md: 0 4px 12px rgba(0,0,0,0.08), 0 1px 3px rgba(0,0,0,0.04);
    --shadow-lg: 0 10px 32px rgba(0,0,0,0.1), 0 2px 8px rgba(0,0,0,0.04);
    --radius-sm: 6px;
    --radius: 10px;
    --radius-lg: 14px;
    --radius-xl: 20px;
}

html.dark {
    --bg: #0d1117;
    --surface: #161b22;
    --surface-raised: #1c2128;
    --border: rgba(255,255,255,0.06);
    --border-strong: rgba(255,255,255,0.12);
    --text-primary: #e6edf3;
    --text-secondary: #8b949e;
    --text-muted: #6e7681;
    --accent: #3b82f6;
    --accent-hover: #60a5fa;
    --accent-light: rgba(59,130,246,0.08);
    --accent-light-border: rgba(59,130,246,0.2);
    --green: #10b981;
    --green-light: rgba(16,185,129,0.08);
    --red: #f87171;
    --red-light: rgba(248,113,113,0.08);
    --shadow-sm: 0 1px 2px rgba(0,0,0,0.3);
    --shadow-md: 0 4px 12px rgba(0,0,0,0.4), 0 1px 3px rgba(0,0,0,0.2);
    --shadow-lg: 0 10px 32px rgba(0,0,0,0.5), 0 2px 8px rgba(0,0,0,0.2);
}

html { scroll-behavior: smooth; }

body {
    font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', system-ui, sans-serif;
    background: var(--bg);
    color: var(--text-primary);
    line-height: 1.6;
    min-height: 100vh;
    display: flex;
    flex-direction: column;
    transition: background 0.2s, color 0.2s;
    -webkit-font-smoothing: antialiased;
    width: 100%;
    overflow-x: hidden;
}

header {
    position: sticky;
    top: 0;
    z-index: 100;
    background: rgba(249,250,251,0.85);
    backdrop-filter: blur(12px);
    -webkit-backdrop-filter: blur(12px);
    border-bottom: 0px solid var(--border);
    transition: background 0.2s;
}
html.dark header { background: rgba(13,17,23,0.88); }

.header-inner {
    max-width: 1100px;
    margin: 0 auto;
    padding: 0 24px;
    height: 66px;
    padding-top: 8px;
    display: flex;
    align-items: center;
    justify-content: space-between;
    gap: 20px;
}

.logo {
    display: flex;
    align-items: center;
    gap: 5px;
    text-decoration: none;
}

.logo-mark {
    width: 30px;
    height: 34px;
    flex-shrink: 0;
    position: relative;
    display: flex;
    align-items: center;
    justify-content: center;
}
.logo-mark::before {
    content: "";
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    background: var(--accent);
    border-radius: 0 0 0 0;
    clip-path: polygon(0% 0%, calc(100% - 8px) 0%, 100% 8px, 100% 100%, 0% 100%);
    z-index: 1;
}

.logo-mark::after {
    content: "";
    position: absolute;
    top: 0;
    right: 0;
    width: 8px;
    height: 8px;
    background: rgba(255, 255, 255, 0.4); 
    border-bottom-left-radius: 3px; 
    clip-path: polygon(0 0, 100% 100%, 0 100%);
    z-index: 2;
}

.logo-mark svg { display: block; z-index: 3;}

.logo-dot {
    position: absolute;
    bottom: -2px;
    right: -2px;
    width: 10px;
    height: 10px;
    background-color: #3fb950;
    border-radius: 50%;
    border: 2px solid var(--surface);
    z-index: 4; 
    transition: background-color 0.3s ease;
}
.logo-dot.is-offline {
    background-color: #f85149;
}

.logo-text { line-height: 1.2; }
.logo-name {
    font-size: 30px;
    font-weight: 700;
    color: var(--text-primary);
    letter-spacing: -0.02em;
}
.logo-name span { color: var(--accent); font-weight: 700; }

nav { display: flex; align-items: center; gap: 4px; }

.hamburger-btn {
    display: none;
    width: 34px;
    height: 34px;
    border-radius: var(--radius-sm);
    border: none;
    background: transparent;
    color: var(--text-primary);
    cursor: pointer;
    align-items: center;
    justify-content: center;
    margin-left: auto;
    transition: background 0.15s, color 0.15s;
}
.hamburger-btn:hover { background: var(--border); }
.hamburger-btn svg { transition: transform 0.2s; }

.nav-scrim {
    display: none;
    position: fixed;
    inset: 0;
    background: rgba(0,0,0,0.4);
    z-index: 199;
    opacity: 0;
    transition: opacity 0.25s ease;
}
.nav-scrim.open { opacity: 1; }

.nav-drawer { display: none; }
body.drawer-open { overflow: hidden; }

.nav-link {
    font-size: 13px;
    font-weight: 500;
    color: var(--text-secondary);
    text-decoration: none;
    padding: 6px 12px;
    border-radius: var(--radius-sm);
    transition: color 0.15s, background 0.15s;
}
.nav-link:hover { color: var(--text-primary); background: var(--border); }

.nav-dropdown { position: relative; }
.nav-dropdown-btn {
    font-size: 13px;
    font-weight: 600;
    color: var(--text-secondary);
    padding: 8px 14px;
    border-radius: var(--radius-sm);
    border: none;
    background: none;
    cursor: pointer;
    display: flex;
    align-items: center;
    gap: 6px;
    transition: color 0.15s, background 0.15s;
}
.nav-dropdown-btn:hover { color: var(--text-primary); background: var(--border); }
.nav-dropdown-btn svg { transition: transform 0.2s; }
.nav-dropdown-btn.open svg { transform: rotate(180deg); }

.dropdown-menu {
    position: absolute;
    top: calc(100% + 10px);
    left: 50%;
    min-width: 460px;
    max-width: min(460px, 92vw);
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 4px;
    background: var(--surface-raised);
    border: 1px solid var(--border-strong);
    border-radius: var(--radius-lg);
    box-shadow: var(--shadow-lg);
    padding: 10px;
    overflow: hidden;
    opacity: 0;
    visibility: hidden;
    pointer-events: none;
    transform: translate(-50%, -8px);
    transition: opacity 0.22s ease, transform 0.22s ease, visibility 0.22s;
    z-index: 50;
}
.dropdown-menu.open {
    opacity: 1;
    visibility: visible;
    pointer-events: auto;
    transform: translate(-50%, 0);
}
.dropdown-column {
    display: flex;
    flex-direction: column;
    gap: 2px;
}
.dropdown-column-title {
    font-size: 11px;
    font-weight: 700;
    letter-spacing: 0.04em;
    text-transform: uppercase;
    color: var(--text-muted);
    padding: 6px 10px 8px;
}
.dropdown-item {
    display: flex;
    align-items: center;
    gap: 10px;
    padding: 9px 10px;
    text-decoration: none;
    font-size: 13px;
    font-weight: 500;
    color: var(--text-primary);
    border-radius: var(--radius-sm);
    transition: background 0.12s;
}
.dropdown-item:hover { background: var(--bg); }
.dropdown-icon {
    width: 28px;
    height: 28px;
    border-radius: var(--radius-sm);
    background: var(--accent-light);
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 14px;
    flex-shrink: 0;
}

.theme-btn {
    width: 34px;
    height: 34px;
    border-radius: var(--radius-sm);
    border: none;
    background: transparent;
    cursor: pointer;
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 16px;
    transition: background 0.15s, border-color 0.15s;
}
.theme-btn:hover { background: var(--bg); }

.nav-divider {
    width: 1px;
    height: 20px;
    background: var(--border-strong);
    margin: 0 4px;
}

@media (max-width: 600px) {
    .header-inner {
        padding: 0 12px;
        gap: 8px;
    }
    .logo-name {
        font-size: 20px;
    }

    nav { display: none; }
    .hamburger-btn { display: flex; }

    .nav-scrim { display: block; pointer-events: none; }
    .nav-scrim.open { pointer-events: auto; }

    .nav-drawer {
        display: flex;
        position: fixed;
        top: 0;
        right: 0;
        bottom: 0;
        width: min(82vw, 320px);
        max-width: 100vw;
        box-sizing: border-box;
        background: var(--surface);
        border-left: 1px solid var(--border);
        box-shadow: var(--shadow-lg);
        z-index: 200;
        flex-direction: column;
        gap: 4px;
        padding: 20px 16px;
        transform: translateX(100%);
        transition: transform 0.3s ease;
        overflow-y: auto;
        overflow-x: hidden;
    }
    .nav-drawer.open { transform: translateX(0); }

    .nav-drawer-close {
        align-self: flex-end;
        width: 32px;
        height: 32px;
        border: none;
        background: transparent;
        border-radius: 50%;
        cursor: pointer;
        display: flex;
        align-items: center;
        justify-content: center;
        margin-bottom: 8px;
        transition: background 0.15s;
    }
    .nav-drawer-close:hover { background: var(--border); }

    .nav-drawer .nav-link,
    .nav-drawer .theme-btn-mobile {
        width: 100%;
        justify-content: flex-start;
        padding: 12px 10px;
        border-radius: var(--radius-sm);
        font-size: 14px;
    }
    .theme-btn-mobile {
        display: flex;
        align-items: center;
        gap: 10px;
        background: none;
        border: none;
        color: var(--text-secondary);
        cursor: pointer;
        width: 100%;
        text-align: left;
        transition: background 0.15s;
    }
    .theme-btn-mobile:hover { background: var(--border); }

    .nav-drawer .nav-dropdown-btn {
        width: 100%;
        justify-content: space-between;
        padding: 12px 10px;
        box-sizing: border-box;
        text-align: left;
    }
    .nav-drawer .dropdown-menu {
        position: static;
        left: auto;
        display: none;
        grid-template-columns: 1fr;
        min-width: 0;
        width: 100%;
        border: none;
        box-shadow: none;
        background: var(--bg);
        border-radius: var(--radius);
        opacity: 1;
        visibility: visible;
        pointer-events: auto;
        transform: none;
        padding: 8px;
        margin-top: 4px;
    }
    .nav-drawer .dropdown-menu.open {
        display: grid;
        transform: none;
        opacity: 1;
        visibility: visible;
        pointer-events: auto;
    }
    .nav-drawer .dropdown-column + .dropdown-column {
        margin-top: 6px;
    }

    .nav-divider { display: none; }
}

main {
    max-width: 800px;
    margin: 0 auto;
    padding: 50px 24px 80px;
    width: 100%;
}

.back-link {
    display: inline-flex;
    align-items: center;
    gap: 6px;
    color: var(--accent);
    text-decoration: none;
    font-size: 13.5px;
    font-weight: 600;
    margin-bottom: 24px;
}
.back-link:hover { text-decoration: underline; }

.policy-card {
    background: var(--surface);
    border: 1px solid var(--border-strong);
    border-radius: var(--radius-xl);
    padding: 40px;
    box-shadow: var(--shadow-md);
}

@media (max-width: 600px) {
    .policy-card { padding: 24px; }
}

h1 {
    font-size: clamp(26px, 4vw, 34px);
    font-weight: 800;
    letter-spacing: -0.03em;
    color: var(--text-primary);
    margin-bottom: 6px;
    line-height: 1.2;
}

.last-updated {
    font-size: 13px;
    color: var(--text-muted);
    margin-bottom: 28px;
}

h2 {
    font-size: 17px;
    font-weight: 700;
    letter-spacing: -0.01em;
    color: var(--text-primary);
    margin-top: 32px;
    margin-bottom: 10px;
}

p {
    font-size: 14.5px;
    color: var(--text-secondary);
    margin-bottom: 16px;
    line-height: 1.65;
}

ul {
    margin-left: 20px;
    margin-bottom: 16px;
    color: var(--text-secondary);
    font-size: 14.5px;
}

li { margin-bottom: 6px; }

.highlight-box {
    background-color: var(--accent-light);
    border-left: 4px solid var(--accent);
    padding: 16px;
    border-radius: 0 var(--radius) var(--radius) 0;
    margin: 24px 0;
    font-size: 13.5px;
    color: var(--text-primary);
    line-height: 1.6;
}

.highlight-box strong {
    color: var(--accent);
}

footer {
    border-top: 1px solid var(--border);
    background: var(--surface);
    padding: 28px 24px;
    margin-top: auto;
}

.footer-inner {
    max-width: 1100px;
    margin: 0 auto;
    display: flex;
    align-items: center;
    justify-content: space-between;
    gap: 20px;
    flex-wrap: wrap;
}

.footer-copy { font-size: 12.5px; color: var(--text-muted); }
.footer-links { display: flex; align-items: center; gap: 20px; }
.footer-link { font-size: 12.5px; font-weight: 500; color: var(--text-muted); text-decoration: none; transition: color 0.15s; }
.footer-link:hover { color: var(--text-primary); }

.lang-container {
    position: relative;
    display: inline-block;
}

.lang-btn {
    font-size: 12.5px;
    font-weight: 500;
    color: var(--text-muted);
    background: none;
    border: 1px solid var(--border-strong);
    padding: 6px 12px;
    border-radius: var(--radius-sm);
    cursor: pointer;
    display: flex;
    align-items: center;
    gap: 6px;
    transition: all 0.15s;
}

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

.lang-menu {
    position: absolute;
    bottom: calc(100% + 8px);
    right: 0;
    min-width: 140px;
    background: var(--surface-raised);
    border: 1px solid var(--border-strong);
    border-radius: var(--radius);
    box-shadow: var(--shadow-lg);
    overflow: hidden;
    opacity: 0;
    visibility: hidden;
    transform: translateY(4px);
    transition: all 0.15s ease;
    z-index: 150;
}

.lang-menu.open {
    opacity: 1;
    visibility: visible;
    transform: translateY(0);
}

.lang-item {
    width: 100%;
    background: none;
    border: none;
    display: flex;
    align-items: center;
    justify-content: space-between;
    padding: 10px 14px;
    font-size: 13px;
    font-weight: 500;
    color: var(--text-primary);
    cursor: pointer;
    text-align: left;
    transition: background 0.1s;
}

.lang-item:hover {
    background: var(--bg);
}

.lang-item.active {
    color: var(--accent);
    font-weight: 600;
}