/* ==========================================================================
   IP Checker - Modern Minimalist Design System
   ========================================================================== */

:root {
    /* 色彩系统 - 深色模式默认 */
    --bg-primary: #0b0f17;
    --bg-surface: #121824;
    --bg-surface-elevated: #1a2234;
    --bg-surface-hover: #222d42;
    --border-subtle: #1e293b;
    --border-strong: #334155;
    
    --text-primary: #f8fafc;
    --text-secondary: #94a3b8;
    --text-muted: #64748b;
    
    --accent-blue: #38bdf8;
    --accent-blue-subtle: rgba(56, 189, 248, 0.12);
    --accent-v4: #38bdf8;
    --accent-v4-bg: rgba(56, 189, 248, 0.15);
    --accent-v6: #34d399;
    --accent-v6-bg: rgba(52, 211, 153, 0.15);
    --accent-warn: #fbbf24;
    --accent-warn-bg: rgba(251, 191, 36, 0.15);
    --accent-error: #f87171;
    --accent-error-bg: rgba(248, 113, 113, 0.15);
    
    --font-sans: 'Inter', -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, sans-serif;
    --font-mono: 'Fira Code', ui-monospace, SFMono-Regular, Menlo, Monaco, Consolas, monospace;

    --radius-sm: 6px;
    --radius-md: 10px;
    --radius-lg: 16px;
    --radius-xl: 20px;

    --shadow-sm: 0 1px 2px 0 rgba(0, 0, 0, 0.05);
    --shadow-md: 0 4px 6px -1px rgba(0, 0, 0, 0.2), 0 2px 4px -2px rgba(0, 0, 0, 0.2);
    --shadow-lg: 0 10px 15px -3px rgba(0, 0, 0, 0.3), 0 4px 6px -4px rgba(0, 0, 0, 0.3);

    --transition: all 0.2s cubic-bezier(0.4, 0, 0.2, 1);
}

/* 浅色主题模式 */
body.theme-light {
    --bg-primary: #f8fafc;
    --bg-surface: #ffffff;
    --bg-surface-elevated: #f1f5f9;
    --bg-surface-hover: #e2e8f0;
    --border-subtle: #e2e8f0;
    --border-strong: #cbd5e1;
    
    --text-primary: #0f172a;
    --text-secondary: #475569;
    --text-muted: #94a3b8;

    --accent-blue: #0284c7;
    --accent-blue-subtle: rgba(2, 132, 199, 0.1);
    --accent-v4: #0284c7;
    --accent-v4-bg: rgba(2, 132, 199, 0.12);
    --accent-v6: #059669;
    --accent-v6-bg: rgba(5, 150, 105, 0.12);
    
    --shadow-md: 0 4px 6px -1px rgba(0, 0, 0, 0.05), 0 2px 4px -2px rgba(0, 0, 0, 0.05);
    --shadow-lg: 0 10px 15px -3px rgba(0, 0, 0, 0.08), 0 4px 6px -4px rgba(0, 0, 0, 0.05);
}

/* 全局重置 */
*, *::before, *::after {
    box-sizing: border-box;
    margin: 0;
    padding: 0;
}

body {
    font-family: var(--font-sans);
    background-color: var(--bg-primary);
    color: var(--text-primary);
    line-height: 1.5;
    -webkit-font-smoothing: antialiased;
    min-height: 100vh;
    display: flex;
    flex-direction: column;
    transition: background-color 0.3s ease, color 0.3s ease;
}

.app-container {
    max-width: 900px;
    margin: 0 auto;
    padding: 24px 20px 48px;
    width: 100%;
    flex: 1;
    display: flex;
    flex-direction: column;
    gap: 28px;
}

/* ==========================================================================
   Header & Nav
   ========================================================================= */
.site-header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 12px 0;
    border-bottom: 1px solid var(--border-subtle);
}

.brand {
    display: flex;
    align-items: center;
    gap: 12px;
}

.logo-icon {
    display: flex;
    align-items: center;
    justify-content: center;
    width: 38px;
    height: 38px;
    background-color: var(--bg-surface-elevated);
    border: 1px solid var(--border-strong);
    border-radius: var(--radius-md);
    color: var(--accent-blue);
}

.brand-text h1 {
    font-size: 1.2rem;
    font-weight: 700;
    letter-spacing: -0.02em;
    line-height: 1.2;
}

.badge-subtle {
    font-size: 0.72rem;
    font-weight: 600;
    color: var(--text-muted);
    letter-spacing: 0.05em;
    text-transform: uppercase;
}

.btn-icon {
    background: var(--bg-surface);
    border: 1px solid var(--border-subtle);
    color: var(--text-secondary);
    width: 38px;
    height: 38px;
    border-radius: var(--radius-md);
    display: flex;
    align-items: center;
    justify-content: center;
    cursor: pointer;
    transition: var(--transition);
}

.btn-icon:hover {
    background: var(--bg-surface-hover);
    color: var(--text-primary);
    border-color: var(--border-strong);
}

/* 主题切换图标控制 */
body.theme-dark .icon-moon { display: none; }
body.theme-dark .icon-sun { display: block; }
body.theme-light .icon-sun { display: none; }
body.theme-light .icon-moon { display: block; }

/* ==========================================================================
   Main Hero Card (主 IP 展示)
   ========================================================================== */
.hero-card {
    background: var(--bg-surface);
    border: 1px solid var(--border-subtle);
    border-radius: var(--radius-xl);
    padding: 32px 28px;
    box-shadow: var(--shadow-lg);
    display: flex;
    flex-direction: column;
    gap: 20px;
    position: relative;
    overflow: hidden;
}

.hero-header {
    display: flex;
    justify-content: space-between;
    align-items: center;
}

.hero-label {
    font-size: 0.85rem;
    font-weight: 600;
    color: var(--text-secondary);
    text-transform: uppercase;
    letter-spacing: 0.06em;
}

.version-badge {
    padding: 4px 10px;
    border-radius: 9999px;
    font-size: 0.78rem;
    font-weight: 700;
    letter-spacing: 0.03em;
}

.version-badge.ipv4 {
    background: var(--accent-v4-bg);
    color: var(--accent-v4);
    border: 1px solid rgba(56, 189, 248, 0.3);
}

.version-badge.ipv6 {
    background: var(--accent-v6-bg);
    color: var(--accent-v6);
    border: 1px solid rgba(52, 211, 153, 0.3);
}

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

.ip-address {
    font-family: var(--font-mono);
    font-size: clamp(1.6rem, 4vw, 2.5rem);
    font-weight: 700;
    color: var(--text-primary);
    word-break: break-all;
    letter-spacing: -0.02em;
    cursor: pointer;
    transition: color 0.15s ease;
}

.ip-address:hover {
    color: var(--accent-blue);
}

.btn-copy {
    display: inline-flex;
    align-items: center;
    gap: 8px;
    background: var(--bg-surface-elevated);
    border: 1px solid var(--border-strong);
    color: var(--text-primary);
    padding: 10px 18px;
    border-radius: var(--radius-md);
    font-size: 0.9rem;
    font-weight: 600;
    cursor: pointer;
    transition: var(--transition);
    flex-shrink: 0;
}

.btn-copy:hover {
    background: var(--bg-surface-hover);
    border-color: var(--accent-blue);
    transform: translateY(-1px);
}

.ip-meta-bar {
    display: flex;
    align-items: center;
    flex-wrap: wrap;
    gap: 12px;
    padding-top: 14px;
    border-top: 1px solid var(--border-subtle);
}

.meta-item {
    display: inline-flex;
    align-items: center;
    gap: 6px;
    font-size: 0.84rem;
    color: var(--text-secondary);
    background: var(--bg-surface-elevated);
    padding: 6px 12px;
    border-radius: var(--radius-sm);
    border: 1px solid var(--border-subtle);
}

.meta-item svg {
    color: var(--text-muted);
}

.protocol-tag span {
    font-family: var(--font-mono);
    font-size: 0.8rem;
}

/* ==========================================================================
   Dual Stack Section (双栈独立检测)
   ========================================================================== */
.section-title-bar {
    display: flex;
    justify-content: space-between;
    align-items: center;
    margin-bottom: 14px;
}

.section-title-bar h2 {
    font-size: 1.05rem;
    font-weight: 600;
    letter-spacing: -0.01em;
    color: var(--text-primary);
}

.subtitle-tag {
    font-size: 0.78rem;
    color: var(--text-muted);
}

.btn-refresh {
    display: inline-flex;
    align-items: center;
    gap: 6px;
    background: transparent;
    border: 1px solid var(--border-subtle);
    color: var(--text-secondary);
    padding: 6px 12px;
    border-radius: var(--radius-sm);
    font-size: 0.8rem;
    font-weight: 500;
    cursor: pointer;
    transition: var(--transition);
}

.btn-refresh:hover {
    background: var(--bg-surface);
    color: var(--text-primary);
    border-color: var(--border-strong);
}

.btn-refresh.loading svg {
    animation: spin 1s linear infinite;
}

@keyframes spin {
    100% { transform: rotate(360deg); }
}

.dual-stack-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(320px, 1fr));
    gap: 16px;
}

.stack-card {
    background: var(--bg-surface);
    border: 1px solid var(--border-subtle);
    border-radius: var(--radius-lg);
    padding: 20px;
    box-shadow: var(--shadow-sm);
    display: flex;
    flex-direction: column;
    gap: 14px;
    transition: var(--transition);
}

.stack-card:hover {
    border-color: var(--border-strong);
    box-shadow: var(--shadow-md);
}

.stack-card-header {
    display: flex;
    justify-content: space-between;
    align-items: center;
}

.stack-title {
    display: flex;
    align-items: center;
    gap: 8px;
}

.indicator {
    width: 8px;
    height: 8px;
    border-radius: 50%;
}

.indicator-v4 { background-color: var(--accent-v4); box-shadow: 0 0 8px var(--accent-v4); }
.indicator-v6 { background-color: var(--accent-v6); box-shadow: 0 0 8px var(--accent-v6); }

.stack-title h3 {
    font-size: 0.95rem;
    font-weight: 600;
}

.status-badge {
    font-size: 0.72rem;
    padding: 2px 8px;
    border-radius: var(--radius-sm);
    font-weight: 600;
    background: var(--bg-surface-elevated);
    color: var(--text-muted);
}

.status-badge.online {
    background: var(--accent-v6-bg);
    color: var(--accent-v6);
}

.status-badge.offline {
    background: var(--accent-error-bg);
    color: var(--accent-error);
}

.stack-body {
    display: flex;
    flex-direction: column;
    gap: 10px;
}

.stack-ip-wrapper {
    display: flex;
    align-items: center;
    justify-content: space-between;
    gap: 8px;
    background: var(--bg-surface-elevated);
    padding: 10px 14px;
    border-radius: var(--radius-md);
    border: 1px solid var(--border-subtle);
    min-height: 48px;
}

.stack-ip {
    font-family: var(--font-mono);
    font-size: 0.92rem;
    font-weight: 600;
    color: var(--text-primary);
    word-break: break-all;
}

.btn-copy-mini {
    background: transparent;
    border: none;
    color: var(--text-secondary);
    cursor: pointer;
    display: flex;
    align-items: center;
    padding: 4px;
    border-radius: var(--radius-sm);
    transition: var(--transition);
}

.btn-copy-mini:hover {
    color: var(--accent-blue);
    background: var(--bg-surface-hover);
}

.stack-meta {
    display: flex;
    justify-content: space-between;
    align-items: center;
    font-size: 0.75rem;
    color: var(--text-muted);
    padding: 0 4px;
}

.stack-meta .latency {
    font-family: var(--font-mono);
}

/* ==========================================================================
   CLI Guide Section
   ========================================================================== */
.cli-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
    gap: 12px;
}

.cli-item {
    background: var(--bg-surface);
    border: 1px solid var(--border-subtle);
    border-radius: var(--radius-md);
    padding: 12px 14px;
    display: flex;
    flex-direction: column;
    gap: 8px;
}

.cli-desc {
    font-size: 0.78rem;
    color: var(--text-secondary);
    font-weight: 500;
}

.cli-code-row {
    display: flex;
    align-items: center;
    justify-content: space-between;
    gap: 8px;
    background: var(--bg-surface-elevated);
    padding: 6px 10px;
    border-radius: var(--radius-sm);
    border: 1px solid var(--border-subtle);
}

.cli-code-row code {
    font-family: var(--font-mono);
    font-size: 0.8rem;
    color: var(--text-primary);
    overflow: hidden;
    text-overflow: ellipsis;
    white-space: nowrap;
}

.btn-copy-code {
    background: transparent;
    border: none;
    color: var(--accent-blue);
    font-size: 0.75rem;
    font-weight: 600;
    cursor: pointer;
    padding: 2px 6px;
    border-radius: var(--radius-sm);
    transition: var(--transition);
    flex-shrink: 0;
}

.btn-copy-code:hover {
    background: var(--accent-blue-subtle);
}

/* ==========================================================================
   Details Table Section
   ========================================================================== */
.details-card {
    background: var(--bg-surface);
    border: 1px solid var(--border-subtle);
    border-radius: var(--radius-lg);
    padding: 16px 20px;
}

.details-table {
    display: flex;
    flex-direction: column;
}

.detail-row {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 10px 0;
    border-bottom: 1px solid var(--border-subtle);
    font-size: 0.85rem;
    gap: 16px;
}

.detail-row:last-child {
    border-bottom: none;
}

.dt-label {
    color: var(--text-secondary);
    font-weight: 500;
    flex-shrink: 0;
}

.dt-value {
    color: var(--text-primary);
    text-align: right;
    word-break: break-all;
}

.dt-value.monospace {
    font-family: var(--font-mono);
    font-size: 0.8rem;
}

/* ==========================================================================
   Footer
   ========================================================================== */
.site-footer {
    text-align: center;
    padding-top: 16px;
    color: var(--text-muted);
    font-size: 0.8rem;
    border-top: 1px solid var(--border-subtle);
}

/* ==========================================================================
   Toast Notification
   ========================================================================== */
.toast {
    position: fixed;
    bottom: 24px;
    left: 50%;
    transform: translateX(-50%) translateY(100px);
    background: #0f172a;
    color: #f8fafc;
    border: 1px solid var(--border-strong);
    padding: 10px 20px;
    border-radius: 9999px;
    font-size: 0.85rem;
    font-weight: 500;
    box-shadow: var(--shadow-lg);
    opacity: 0;
    pointer-events: none;
    transition: transform 0.25s cubic-bezier(0.175, 0.885, 0.32, 1.275), opacity 0.25s ease;
    z-index: 1000;
}

.toast.show {
    opacity: 1;
    transform: translateX(-50%) translateY(0);
}

/* ==========================================================================
   Responsive
   ========================================================================== */
@media (max-width: 640px) {
    .app-container {
        padding: 16px 12px 32px;
        gap: 20px;
    }

    .hero-card {
        padding: 20px 16px;
    }

    .ip-display-group {
        flex-direction: column;
        align-items: flex-start;
    }

    .btn-copy {
        width: 100%;
        justify-content: center;
    }

    .dual-stack-grid {
        grid-template-columns: 1fr;
    }

    .detail-row {
        flex-direction: column;
        align-items: flex-start;
        gap: 4px;
    }

    .dt-value {
        text-align: left;
    }
}