:root {
    --bg-primary: #f0f2ff;
    --bg-secondary: #ffffff;
    --bg-card: #ffffff;
    --text-primary: #1a1a2e;
    --text-secondary: #6b7280;
    --border-color: #e5e7eb;
    --accent-color: #6366f1;
    --theme-btn-active: #6366f1;
    --danger-bg: #fee2e2;
    --danger-border: #ef4444;
    --danger-btn: #ef4444;
}

[data-theme="dark"] {
    --bg-primary: #0f1419;
    --bg-secondary: #1a1f2e;
    --bg-card: #1a1f2e;
    --text-primary: #ffffff;
    --text-secondary: #9ca3af;
    --border-color: #374151;
    --accent-color: #818cf8;
    --theme-btn-active: #818cf8;
    --danger-bg: #1f1419;
    --danger-border: #dc2626;
    --danger-btn: #dc2626;
}

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

body {
    font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, "Helvetica Neue", Arial, sans-serif;
    background-color: var(--bg-primary);
    color: var(--text-primary);
    min-height: 100vh;
    transition: background-color 0.3s ease, color 0.3s ease;
}

html {
    scroll-behavior: smooth;
}

.container {
    max-width: 1024px;
    margin: 0 auto;
    padding: 20px;
    min-height: 100vh;
    display: flex;
    flex-direction: column;
}

/* Top navigation bar */
.topbar {
    position: sticky;
    top: 0;
    z-index: 100;
    display: grid;
    grid-template-columns: 1fr auto;
    align-items: center;
    gap: 12px;
    padding: 14px 0;
    background: var(--bg-primary);
}

.brand {
    font-weight: 700;
    font-size: 1.1rem;
    text-decoration: none;
    color: var(--text-primary);
}
/* Common centered header */
.site-header {
    display: flex;
    justify-content: center;
    align-items: center;
    padding: 24px 0 12px;
}

.header-center {
    display: flex;
    gap: 12px;
    flex-wrap: wrap;
    justify-content: center;
}

.header-button {
    display: inline-block;
    text-decoration: none;
    padding: 12px 16px;
    border-radius: 10px;
    border: 1px solid var(--border-color);
    background: var(--bg-secondary);
    color: var(--text-primary);
    font-weight: 600;
    transition: background-color 0.2s ease, color 0.2s ease, border-color 0.2s ease;
    white-space: nowrap;
}

.header-button:hover {
    border-color: var(--accent-color);
    color: var(--accent-color);
    background: color-mix(in srgb, var(--accent-color) 8%, transparent);
}

.header-button:focus-visible {
    outline: none;
    border-color: var(--accent-color);
    box-shadow: 0 0 0 3px color-mix(in srgb, var(--accent-color) 25%, transparent);
}

.header-button:active {
    background: color-mix(in srgb, var(--accent-color) 14%, transparent);
    border-color: var(--accent-color);
}

.main-content {
    flex: 1;
    background-color: var(--bg-card);
    border-radius: 12px;
    padding: 30px;
    margin-bottom: 30px;
    /* Center the content area and cap its width */
    justify-self: center; /* centers within grid column */
    width: 100%;
    max-width: 740px;
    box-shadow: 0 1px 3px rgba(0, 0, 0, 0.1);
}

.page-title {
    font-size: 1.75rem;
    font-weight: 700;
    margin-bottom: 18px;
}

/* Desktop layout: left sidebar + content */
.page-layout {
    display: grid;
    grid-template-columns: 260px 1fr;
    gap: 24px;
}

.sidebar {
    position: sticky;
    top: 24px;
    height: max-content;
}

.sidebar-nav {
    display: flex;
    flex-direction: column;
    gap: 8px;
}

/* Hidden by default; shown on mobile */
.hamburger { display: none; }

/* Modern dropdown for mobile menu */
.mobile-menu {
    position: fixed;
    top: 58px;
    left: 16px;
    width: min(240px, 90vw);
    background: var(--bg-card);
    border: 1px solid var(--border-color);
    border-radius: 12px;
    padding: 10px;
    box-shadow: 0 10px 30px rgba(0,0,0,0.12);
    z-index: 1002; /* ensure above content and theme toggle */
}

/* Tabs layout */
.tabs-layout {
    display: grid;
    grid-template-columns: 220px 1fr;
    gap: 24px;
}

.tab-list {
    display: flex;
    flex-direction: column;
    gap: 8px;
}

.tab-button {
    text-align: left;
    padding: 12px 14px;
    border-radius: 8px;
    border: 1px solid var(--border-color);
    background: var(--bg-secondary);
    color: var(--text-primary);
    cursor: pointer;
    transition: background-color 0.2s ease, color 0.2s ease, border-color 0.2s ease;
}

.tab-button[aria-selected="true"] {
    border-color: var(--accent-color);
    color: var(--accent-color);
    background: color-mix(in srgb, var(--accent-color) 8%, transparent);
}

.tab-button:hover {
    border-color: var(--accent-color);
}

/* Sidebar links (anchor-based navigation) */
.sidebar-link {
    display: block;
    text-decoration: none;
    text-align: left;
    padding: 12px 14px;
    border-radius: 8px;
    border: 1px solid var(--border-color);
    background: var(--bg-secondary);
    color: var(--text-primary);
    transition: background-color 0.2s ease, color 0.2s ease, border-color 0.2s ease;
}

.sidebar-link:hover {
    border-color: var(--accent-color);
    color: var(--accent-color);
}

.tab-panels {
    min-height: 400px;
}

.tab-panel {
    animation: fadeIn 140ms ease;
}

.main-content > section + section {
    margin-top: 32px;
    padding-top: 16px;
    border-top: 3px double var(--border-color);
}

.section-title {
    font-size: 1.25rem;
    font-weight: 600;
    margin-bottom: 16px;
    padding-bottom: 10px;
    border-bottom: 2px solid var(--border-color);
}

.legal-content p,
.legal-content li {
    color: var(--text-secondary);
    line-height: 1.8;
}

.legal-content > * + * {
    margin-top: 10px;
}

.legal-content ol,
.legal-content ul {
    padding-left: 1.25rem;
    display: grid;
    gap: 8px;
}

@keyframes fadeIn {
    from { opacity: 0 }
    to { opacity: 1 }
}

.terms-table {
    display: flex;
    flex-direction: column;
    gap: 0;
    border: 1px solid var(--border-color);
    border-radius: 10px;
    overflow: hidden;
}

.term-row {
    display: grid;
    grid-template-columns: 200px 1fr;
    padding: 14px 16px;
    border-bottom: 1px solid var(--border-color);
    background: var(--bg-secondary);
}

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

.term-row:nth-child(odd) {
    background: color-mix(in srgb, var(--accent-color) 5%, var(--bg-secondary));
}

.term-label {
    font-weight: 600;
    color: var(--text-primary);
}

.term-value {
    color: var(--text-secondary);
    line-height: 1.6;
}

.theme-toggle {
    position: fixed;
    top: 20px;
    right: 20px;
    background-color: var(--bg-card);
    border: 2px solid var(--border-color);
    width: 50px;
    height: 50px;
    cursor: pointer;
    display: flex;
    align-items: center;
    justify-content: center;
    border-radius: 50%;
    transition: all 0.3s ease;
    color: var(--text-primary);
    font-size: 1.5rem;
    box-shadow: 0 2px 8px rgba(0, 0, 0, 0.1);
    z-index: 1000;
}

.theme-toggle:hover {
    transform: scale(1.1);
    box-shadow: 0 4px 12px rgba(0, 0, 0, 0.15);
    border-color: var(--accent-color);
}

.theme-toggle:active {
    transform: scale(0.95);
}

.theme-icon {
    font-size: 1.5rem;
}

.theme-label {
    font-size: 0.875rem;
}

.redirect-message {
    text-align: center;
    padding: 60px 20px;
    background-color: var(--bg-card);
    border-radius: 12px;
    margin-top: 100px;
}

.redirect-message h1 {
    font-size: 1.5rem;
    margin-bottom: 20px;
    color: var(--text-primary);
}

.redirect-message p {
    color: var(--text-secondary);
    margin-bottom: 10px;
}

.redirect-message a {
    color: var(--accent-color);
    text-decoration: none;
}

.redirect-message a:hover {
    text-decoration: underline;
}

@media (max-width: 640px) {
    .tabs-layout {
        grid-template-columns: 1fr;
    }

    .tab-list {
        flex-direction: row;
        gap: 10px;
        overflow-x: auto;
    }

    .tab-button {
        white-space: nowrap;
    }

    /* New responsive layout rules */
    .page-layout {
        display: grid;
        grid-template-columns: 1fr;
        gap: 16px;
    }

    .sidebar { display: none; }

    .hamburger {
        position: fixed;
        top: 16px;
        left: 16px;
        display: inline-flex;
        align-items: center;
        justify-content: center;
        width: 44px;
        height: 44px;
        padding: 0;
        border-radius: 10px;
        border: 1px solid var(--border-color);
        background: var(--bg-secondary);
        color: var(--text-primary);
        cursor: pointer;
        z-index: 1001;
        box-shadow: 0 6px 18px rgba(0,0,0,0.12);
    }

    .mobile-menu { left: 16px; right: auto; top: 66px; }

    .mobile-link {
        text-decoration: none;
        color: var(--text-primary);
        padding: 8px 10px;
        border-radius: 6px;
        display: block;
    }

    .mobile-link:hover {
        background: color-mix(in srgb, var(--accent-color) 10%, transparent);
    }
    .term-row {
        grid-template-columns: 1fr;
        gap: 6px;
    }
    
    .term-label {
        flex: none;
    }
    
    .theme-toggle {
        width: 45px;
        height: 45px;
        top: 15px;
        right: 15px;
    }
}