:root {
    --bg: #0d0f14;
    --surf: #141720;
    --surf2: #1c2030;
    --brd: rgba(255,255,255,0.07);
    --brd2: rgba(255,255,255,0.13);
    --tx: #e8eaf0;
    --mu: #8a90a8;
    --ac: #00c8e8;
    --acd: rgba(0,200,232,0.08);
    --acd2: rgba(0,200,232,0.16);
    --gr: #4ade80;
    --am: #fbbf24;
    --rail: 48px;
    --full: 220px;
    --top: 52px;
    --d-nt-stroke: #00c8e8;
    --d-nt-fill: #1c2030;
    --d-nt-text: #00c8e8;
    --d-t-stroke: #4ade80;
    --d-t-fill: #1c2030;
    --d-t-text: #4ade80;
    --d-line: #8a90a8;
    --d-cap: #8a90a8;
}

.lt {
    --bg: #eef0f5;
    --surf: #ffffff;
    --surf2: #e2e6ef;
    --brd: rgba(0,0,0,0.07);
    --brd2: rgba(0,0,0,0.14);
    --tx: #1a1d2e;
    --mu: #5a6080;
    --ac: #0077aa;
    --acd: rgba(0,119,170,0.08);
    --acd2: rgba(0,119,170,0.16);
    --gr: #16a34a;
    --am: #b45309;
    --d-nt-stroke: #008000;
    --d-nt-fill: #ffffff;
    --d-nt-text: #008000;
    --d-t-stroke: #0000ff;
    --d-t-fill: #ffffff;
    --d-t-text: #0000ff;
    --d-line: #000000;
    --d-cap: #000000;
}

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

html, body {
    height: 100%;
    background: var(--bg);
    color: var(--tx);
    font-family: 'Inter', sans-serif;
    line-height: 1.5;
}

/* ── LAYOUT SHELL ── */
.page {
    display: flex;
    flex-direction: column;
    min-height: 100vh;
    background: var(--bg);
    transition: background 0.15s, color 0.15s;
}

/* ── TOPBAR ── */
.topbar {
    position: sticky;
    top: 0;
    z-index: 100;
    height: var(--top);
    background: var(--surf);
    border-bottom: 0.5px solid var(--brd2);
    display: flex;
    align-items: center;
    padding: 0 8px;
    flex-shrink: 0;
}

.hbtn {
    width: 30px;
    height: 30px;
    background: var(--surf2);
    border: 0.5px solid var(--brd2);
    border-radius: 6px;
    display: flex;
    align-items: center;
    justify-content: center;
    cursor: pointer;
    color: var(--mu);
    flex-shrink: 0;
    margin-right: 14px;
    transition: color 0.12s, border-color 0.12s;
}

    .hbtn:hover {
        color: var(--tx);
        border-color: var(--ac);
    }

.logo {
    font-family: 'JetBrains Mono', monospace;
    font-size: 15px;
    font-weight: 600;
    color: var(--ac);
    display: flex;
    align-items: center;
    gap: 9px;
    white-space: nowrap;
    text-decoration: none;
}

.logo-box {
    width: 28px;
    height: 28px;
    background: var(--acd2);
    border: 0.5px solid var(--ac);
    border-radius: 7px;
    display: flex;
    align-items: center;
    justify-content: center;
    flex-shrink: 0;
}

.tnav {
    display: flex;
    align-items: center;
    gap: 2px;
    margin-left: auto;
}

    .tnav a {
        font-family: 'Inter', sans-serif;
        font-size: 14px;
        font-weight: 500;
        color: var(--mu);
        text-decoration: none;
        padding: 7px 13px;
        border-radius: 7px;
        cursor: pointer;
        transition: color 0.12s, background 0.12s;
    }

        .tnav a:hover {
            color: var(--tx);
            background: var(--acd);
        }

    .tnav .login {
        color: var(--ac);
        border: 0.5px solid var(--ac);
        margin-left: 8px;
    }

        .tnav .login:hover {
            background: var(--acd2);
        }

.ttheme {
    width: 30px;
    height: 30px;
    background: var(--surf2);
    border: 0.5px solid var(--brd2);
    border-radius: 6px;
    display: flex;
    align-items: center;
    justify-content: center;
    cursor: pointer;
    margin-left: 10px;
    color: var(--mu);
    transition: color 0.12s;
}

    .ttheme:hover {
        color: var(--tx);
    }

/* ── ABOUT DROPDOWN ── */
.about-menu {
    position: relative;
}

.about-btn {
    font-family: 'Inter', sans-serif;
    font-size: 14px;
    font-weight: 500;
    color: var(--mu);
    text-decoration: none;
    padding: 7px 13px;
    border-radius: 7px;
    cursor: pointer;
    transition: color 0.12s, background 0.12s;
    display: flex;
    align-items: center;
    gap: 5px;
    background: none;
    border: none;
}

    .about-btn:hover {
        color: var(--tx);
        background: var(--acd);
    }

.about-dropdown {
    display: none;
    position: absolute;
    top: calc(100% + 6px);
    left: 0;
    background: var(--surf);
    border: 0.5px solid var(--brd2);
    border-radius: 8px;
    min-width: 240px;
    box-shadow: 0 8px 24px rgba(0,0,0,0.3);
    z-index: 200;
    overflow: hidden;
}

    .about-dropdown.open {
        display: block;
    }

/* ── BODY ── */
.body {
    display: flex;
    flex: 1;
    min-height: 0;
}

/* ── SIDEBAR ── */
.sidebar {
    width: var(--full);
    min-width: var(--full);
    background: var(--surf);
    border-right: 0.5px solid var(--brd2);
    display: flex;
    flex-direction: column;
    position: sticky;
    top: var(--top);
    height: calc(100vh - var(--top));
    overflow: hidden;
    flex-shrink: 0;
    transition: width 0.2s ease, min-width 0.2s ease;
}

    .sidebar.rail {
        width: var(--rail);
        min-width: var(--rail);
    }

.sb-scroll {
    flex: 1;
    overflow-y: auto;
    overflow-x: hidden;
    padding: 14px 0 0;
}

    .sb-scroll::-webkit-scrollbar {
        width: 3px;
    }

    .sb-scroll::-webkit-scrollbar-thumb {
        background: var(--brd2);
        border-radius: 2px;
    }

.sb-section {
    padding: 0 8px 12px;
}

.sb-label {
    font-family: 'JetBrains Mono', monospace;
    font-size: 9px;
    font-weight: 500;
    letter-spacing: 1.5px;
    color: var(--mu);
    text-transform: uppercase;
    padding: 0 6px 7px;
    display: flex;
    align-items: center;
    gap: 6px;
    white-space: nowrap;
    overflow: hidden;
    transition: opacity 0.15s, height 0.2s;
}

    .sb-label::after {
        content: '';
        flex: 1;
        height: 0.5px;
        background: var(--brd2);
    }

.rail .sb-label {
    opacity: 0;
    height: 0;
    padding: 0;
    pointer-events: none;
}

.sb-item {
    display: flex;
    align-items: center;
    gap: 10px;
    padding: 8px 8px;
    border-radius: 7px;
    font-size: 13px;
    font-weight: 500;
    color: var(--mu);
    cursor: pointer;
    transition: color 0.12s, background 0.12s;
    position: relative;
    white-space: nowrap;
    overflow: hidden;
    text-decoration: none;
}

    .sb-item:hover {
        color: var(--tx);
        background: var(--acd);
    }

    .sb-item.active {
        color: var(--ac);
        background: var(--acd2);
    }

        .sb-item.active::before {
            content: '';
            position: absolute;
            left: 0;
            top: 5px;
            bottom: 5px;
            width: 2px;
            background: var(--ac);
            border-radius: 2px;
        }

.rail .sb-item.active::before {
    display: none;
}

.rail .sb-item .lbl {
    opacity: 0;
    width: 0;
    overflow: hidden;
}

.sb-badge {
    margin-left: auto;
    font-family: 'JetBrains Mono', monospace;
    font-size: 9px;
    color: var(--mu);
    border: 0.5px solid var(--brd2);
    padding: 1px 5px;
    border-radius: 3px;
    flex-shrink: 0;
    opacity: 0.55;
}

.rail .sb-badge {
    display: none;
}

/* tooltip in rail mode */
.sb-item .tip {
    display: none;
    position: fixed;
    left: calc(var(--rail) + 4px);
    background: var(--surf);
    border: 0.5px solid var(--brd2);
    color: var(--tx);
    font-family: 'JetBrains Mono', monospace;
    font-size: 11px;
    white-space: nowrap;
    padding: 5px 11px;
    border-radius: 6px;
    pointer-events: none;
    z-index: 200;
    box-shadow: 0 4px 16px rgba(0,0,0,0.3);
}

.rail .sb-item:hover .tip {
    display: block;
}

.sb-bottom {
    padding: 8px;
    border-top: 0.5px solid var(--brd2);
    flex-shrink: 0;
}

    .sb-bottom .sb-item {
        margin-bottom: 2px;
    }

.ic {
    width: 16px;
    height: 16px;
    flex-shrink: 0;
    opacity: 0.65;
}

.sb-item.active .ic, .sb-item:hover .ic {
    opacity: 1;
}

/* ── SIDEBAR HISTORY ── */
.sb-history-group-label {
    font-family: 'JetBrains Mono', monospace;
    font-size: 9px;
    font-weight: 500;
    letter-spacing: 1px;
    color: var(--mu);
    text-transform: uppercase;
    padding: 8px 14px 4px;
    opacity: 0.6;
}

.sb-history-item {
    display: flex;
    align-items: flex-start;
    justify-content: space-between;
    padding: 7px 10px;
    border-radius: 7px;
    font-size: 12px;
    color: var(--mu);
    cursor: pointer;
    transition: color 0.12s, background 0.12s;
    gap: 6px;
    position: relative;
}

    .sb-history-item:hover {
        color: var(--tx);
        background: var(--acd);
    }

.sb-history-preview {
    flex: 1;
    font-family: 'JetBrains Mono', monospace;
    font-size: 11px;
    line-height: 1.4;
    overflow: hidden;
    text-overflow: ellipsis;
    white-space: nowrap;
    min-width: 0;
}

.sb-history-delete {
    width: 16px;
    height: 16px;
    flex-shrink: 0;
    opacity: 0;
    background: none;
    border: none;
    color: var(--mu);
    cursor: pointer;
    padding: 0;
    display: flex;
    align-items: center;
    justify-content: center;
    transition: color 0.12s, opacity 0.12s;
    border-radius: 3px;
}

.sb-history-item:hover .sb-history-delete {
    opacity: 1;
}

.sb-history-delete:hover {
    color: #f87171;
}

.rail .sb-history-group-label,
.rail .sb-history-item {
    display: none;
}

/* ── MAIN CONTENT ── */
.main {
    flex: 1;
    min-width: 0;
}

/* ── HERO ── */
.hero {
    padding: 52px 52px 32px;
    max-width: 900px;
}

.badge {
    display: inline-flex;
    align-items: center;
    gap: 7px;
    font-family: 'JetBrains Mono', monospace;
    font-size: 11px;
    color: var(--ac);
    background: var(--acd);
    border: 0.5px solid var(--ac);
    padding: 5px 12px;
    border-radius: 5px;
    letter-spacing: 0.5px;
    margin-bottom: 20px;
}

.dot {
    width: 6px;
    height: 6px;
    border-radius: 50%;
    background: var(--ac);
    animation: pulse 2s infinite;
    flex-shrink: 0;
}

@keyframes pulse {
    0%, 100% {
        opacity: 1;
    }

    50% {
        opacity: 0.3;
    }
}

.hero h1 {
    font-family: 'Inter', sans-serif;
    font-size: 42px;
    font-weight: 700;
    line-height: 1.15;
    letter-spacing: -0.8px;
    margin-bottom: 16px;
    color: var(--tx);
}

    .hero h1 em {
        color: var(--ac);
        font-style: normal;
    }

.hero p {
    font-size: 16px;
    color: var(--mu);
    max-width: 480px;
    line-height: 1.7;
}

/* ── SHOWCASE ── */
.showcase {
    margin: 36px 52px 0;
    border: 0.5px solid var(--brd2);
    border-radius: 12px;
    overflow: visible;
    background: var(--surf);
}

.sc-header {
    padding: 12px 20px;
    border-bottom: 0.5px solid var(--brd2);
    background: var(--surf2);
    border-radius: 12px 12px 0 0;
    display: flex;
    align-items: center;
    gap: 10px;
}

.sc-header-label {
    font-family: 'Inter', sans-serif;
    font-size: 13px;
    font-weight: 500;
    color: var(--tx);
}

.sc-header-sub {
    font-family: 'JetBrains Mono', monospace;
    font-size: 11px;
    color: var(--mu);
}

.sc-body {
    display: flex;
    align-items: center;
    padding: 0;
}

.code-col {
    flex: 0 0 220px;
    padding: 20px;
}

.clabel {
    font-family: 'JetBrains Mono', monospace;
    font-size: 9px;
    letter-spacing: 1px;
    color: var(--mu);
    text-transform: uppercase;
    margin-bottom: 10px;
    display: flex;
    align-items: center;
    gap: 7px;
}

.clabel-dot {
    width: 6px;
    height: 6px;
    border-radius: 50%;
    background: var(--ac);
    opacity: 0.6;
}

.cblock {
    background: var(--bg);
    border: 0.5px solid var(--brd2);
    border-radius: 7px;
    padding: 14px 16px;
    font-family: 'JetBrains Mono', monospace;
    font-size: 13px;
    line-height: 2;
    color: var(--mu);
}

.kw {
    color: var(--ac);
}

.str {
    color: var(--gr);
}

.pu {
    color: var(--am);
}

.arr-col {
    flex-shrink: 0;
    width: 48px;
    display: flex;
    align-items: center;
    justify-content: center;
    color: var(--ac);
    font-size: 22px;
    opacity: 0.35;
}

.svg-col {
    flex: 1;
    padding: 20px;
    display: flex;
    align-items: center;
    min-width: 0;
    overflow: hidden;
}

    .svg-col svg {
        max-width: 100%;
        height: auto;
        display: block;
    }

    /* diagram theme via CSS vars */
    .svg-col .non-terminal-node rect {
        stroke: var(--d-nt-stroke);
        fill: var(--d-nt-fill);
    }

    .svg-col .non-terminal-node text {
        fill: var(--d-nt-text);
    }

    .svg-col .terminal-node rect {
        stroke: var(--d-t-stroke);
        fill: var(--d-t-fill);
    }

    .svg-col .terminal-node text {
        fill: var(--d-t-text);
    }

    .svg-col line {
        stroke: var(--d-line);
    }

    .svg-col path[fill="none"] {
        stroke: var(--d-line);
    }

    .svg-col path[fill="#000000"] {
        stroke: var(--d-cap);
        fill: var(--d-cap);
    }

    .svg-col .terminal-node-start circle,
    .svg-col .terminal-node-end circle {
        stroke: var(--d-cap);
    }

        .svg-col .terminal-node-start circle:last-child,
        .svg-col .terminal-node-end circle:last-child {
            fill: var(--d-cap);
        }

/* ── STATS ── */
.stats {
    display: flex;
    gap: 12px;
    padding: 0 52px;
    margin-top: 20px;
}

.stat {
    flex: 1;
    background: var(--surf);
    border: 0.5px solid var(--brd2);
    border-radius: 10px;
    padding: 16px 18px;
}

.stat-v {
    font-family: 'JetBrains Mono', monospace;
    font-size: 22px;
    font-weight: 600;
    color: var(--ac);
    line-height: 1;
    margin-bottom: 5px;
}

.stat-l {
    font-size: 12px;
    color: var(--mu);
    font-weight: 500;
}

/* ── USER MENU ── */
.user-menu {
    position: relative;
    margin-left: 8px;
}

.user-btn {
    display: flex;
    align-items: center;
    gap: 8px;
    background: var(--surf2);
    border: 0.5px solid var(--brd2);
    border-radius: 7px;
    padding: 5px 10px 5px 6px;
    cursor: pointer;
    color: var(--tx);
    font-family: 'Inter', sans-serif;
    font-size: 14px;
    font-weight: 500;
    transition: border-color 0.12s, background 0.12s;
}

    .user-btn:hover {
        border-color: var(--ac);
        background: var(--acd);
    }

.avatar {
    width: 24px;
    height: 24px;
    border-radius: 50%;
    object-fit: cover;
    flex-shrink: 0;
}

.avatar-fallback {
    width: 24px;
    height: 24px;
    border-radius: 50%;
    background: var(--ac);
    color: var(--bg);
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 12px;
    font-weight: 700;
    flex-shrink: 0;
}

.user-name {
    max-width: 140px;
    overflow: hidden;
    text-overflow: ellipsis;
    white-space: nowrap;
}

.user-dropdown {
    display: none;
    position: absolute;
    top: calc(100% + 6px);
    right: 0;
    background: var(--surf);
    border: 0.5px solid var(--brd2);
    border-radius: 8px;
    min-width: 140px;
    box-shadow: 0 8px 24px rgba(0,0,0,0.3);
    z-index: 200;
    overflow: hidden;
}

    .user-dropdown.open {
        display: block;
    }

    .user-dropdown .divider {
        height: 0.5px;
        background: var(--brd2);
        margin: 4px 0;
    }

.dropdown-item {
    display: flex;
    align-items: center;
    gap: 8px;
    padding: 10px 16px;
    font-size: 14px;
    color: var(--mu);
    text-decoration: none;
    transition: color 0.12s, background 0.12s;
}

    .dropdown-item:hover {
        color: var(--tx);
        background: var(--acd);
    }


/* ── RESULT PAGE ── */
.result-page {
    padding: 80px 52px;
    max-width: 560px;
    display: flex;
    flex-direction: column;
    align-items: flex-start;
    gap: 20px;
}

.result-icon {
    width: 48px;
    height: 48px;
    border-radius: 12px;
    display: flex;
    align-items: center;
    justify-content: center;
    border: 0.5px solid;
}

.result-title {
    font-family: 'Inter', sans-serif;
    font-size: 28px;
    font-weight: 700;
    color: var(--tx);
    letter-spacing: -0.3px;
}

.result-sub {
    font-size: 14px;
    color: var(--mu);
    line-height: 1.7;
    max-width: 420px;
}

.result-actions {
    display: flex;
    gap: 12px;
    margin-top: 8px;
}

.result-btn-primary {
    font-family: 'Inter', sans-serif;
    font-size: 13px;
    font-weight: 500;
    padding: 10px 20px;
    border-radius: 8px;
    border: 0.5px solid var(--ac);
    background: var(--acd2);
    color: var(--ac);
    text-decoration: none;
    transition: background 0.12s, color 0.12s;
}

    .result-btn-primary:hover {
        background: var(--ac);
        color: var(--bg);
    }

.result-btn-secondary {
    font-family: 'Inter', sans-serif;
    font-size: 13px;
    font-weight: 500;
    padding: 10px 20px;
    border-radius: 8px;
    border: 0.5px solid var(--brd2);
    background: var(--surf2);
    color: var(--mu);
    text-decoration: none;
    transition: color 0.12s;
}

    .result-btn-secondary:hover {
        color: var(--tx);
    }

.result-note {
    font-family: 'JetBrains Mono', monospace;
    font-size: 11px;
    color: var(--mu);
    background: var(--surf2);
    border: 0.5px solid var(--brd2);
    border-radius: 6px;
    padding: 10px 14px;
    line-height: 1.6;
}

/* ── FOOTER ── */
.site-footer {
    height: 40px;
    padding: 0 24px;
    background: var(--surf2);
    border-top: 0.5px solid var(--brd2);
    display: flex;
    align-items: center;
    justify-content: space-between;
    flex-shrink: 0;
    font-family: 'JetBrains Mono', monospace;
    font-size: 10px;
    color: var(--mu);
    gap: 16px;
}

.site-footer-left {
    display: flex;
    align-items: center;
    gap: 8px;
}

.site-footer-right {
    display: flex;
    align-items: center;
    gap: 8px;
}

.site-footer-sep {
    opacity: 0.4;
}

.site-footer a {
    color: var(--mu);
    text-decoration: none;
    transition: color 0.12s;
}

    .site-footer a:hover {
        color: var(--ac);
    }