:root {
    color-scheme: dark;

    --bg: #0d1117;
    --panel: #161b22;
    --panel-hover: #1c2128;
    --border: #30363d;

    --text: #e6edf3;
    --muted: #8b949e;

    --accent: #58a6ff;
    --accent-soft: rgba(88, 166, 255, 0.12);

    --max-width: 850px;
}


/* ---------- Base ---------- */

* {
    box-sizing: border-box;
}

html {
    scroll-behavior: smooth;
}

body {
    margin: 0;
    padding: 0;

    background: var(--bg);
    color: var(--text);

    font-family:
        -apple-system,
        BlinkMacSystemFont,
        "Segoe UI",
        Roboto,
        Helvetica,
        Arial,
        sans-serif;

    line-height: 1.6;
}


/* ---------- Header ---------- */

.site-header {
    width: min(var(--max-width), calc(100% - 32px));

    margin: 0 auto;
    padding: 64px 0 38px;
}

.brand {
    display: inline-block;

    margin-bottom: 28px;

    color: var(--muted);

    font-size: 0.85rem;
    font-weight: 600;

    letter-spacing: 0.12em;
    text-decoration: none;
}

.brand:hover {
    color: var(--text);
}

.site-header h1 {
    margin: 0;

    font-size: clamp(2rem, 7vw, 3.2rem);
    line-height: 1.1;

    letter-spacing: -0.035em;
}

.site-header p {
    margin: 14px 0 0;

    color: var(--muted);

    font-size: 1.05rem;
}


/* ---------- Bench ---------- */

.bench {
    width: min(var(--max-width), calc(100% - 32px));

    margin: 0 auto;
}


/* ---------- Individual tools ---------- */

.tool {
    margin-bottom: 12px;

    overflow: hidden;

    background: var(--panel);

    border: 1px solid var(--border);
    border-radius: 10px;
}

.tool summary {
    display: flex;

    align-items: center;
    justify-content: space-between;

    gap: 20px;

    min-height: 64px;

    padding: 0 20px;

    cursor: pointer;

    font-size: 1rem;
    font-weight: 600;

    user-select: none;

    list-style: none;
}

.tool summary::-webkit-details-marker {
    display: none;
}

.tool summary:hover {
    background: var(--panel-hover);
}

.tool[open] summary {
    border-bottom: 1px solid var(--border);
}

.tool[open] {
    box-shadow:
        0 0 0 1px var(--accent-soft);
}


/* ---------- Expand / collapse symbol ---------- */

.tool-symbol {
    display: flex;

    align-items: center;
    justify-content: center;

    width: 30px;
    height: 30px;

    flex-shrink: 0;

    color: var(--muted);

    font-size: 1.35rem;
    font-weight: 400;

    transition: transform 0.18s ease;
}

.tool[open] .tool-symbol {
    transform: rotate(45deg);

    color: var(--accent);
}


/* ---------- Tool body ---------- */

.tool-content {
    padding: 24px 20px 26px;
}

.tool-content > :first-child {
    margin-top: 0;
}

.tool-content > :last-child {
    margin-bottom: 0;
}


/* ---------- Forms ---------- */

.tool-field {
    margin-bottom: 18px;
}

.tool-field label {
    display: block;

    margin-bottom: 7px;

    color: var(--muted);

    font-size: 0.9rem;
    font-weight: 500;
}

.tool-row {
    display: grid;

    grid-template-columns: repeat(2, minmax(0, 1fr));

    gap: 16px;
}

input,
select,
button {
    font: inherit;
}

input,
select {
    width: 100%;

    min-height: 44px;

    padding: 10px 12px;

    background: var(--bg);
    color: var(--text);

    border: 1px solid var(--border);
    border-radius: 7px;

    outline: none;
}

input:focus,
select:focus {
    border-color: var(--accent);

    box-shadow:
        0 0 0 3px var(--accent-soft);
}

button {
    min-height: 44px;

    padding: 10px 16px;

    background: var(--accent);
    color: #0d1117;

    border: 0;
    border-radius: 7px;

    cursor: pointer;

    font-weight: 650;
}

button:hover {
    filter: brightness(1.08);
}


/* ---------- Results ---------- */

.tool-result {
    margin-top: 22px;

    padding: 18px;

    background: var(--bg);

    border: 1px solid var(--border);
    border-radius: 8px;
}

.tool-result-label {
    margin: 0 0 4px;

    color: var(--muted);

    font-size: 0.82rem;
    font-weight: 600;

    letter-spacing: 0.05em;
    text-transform: uppercase;
}

.tool-result-value {
    margin: 0;

    font-size: 1.45rem;
    font-weight: 700;
}


/* ---------- Footer ---------- */

.site-footer {
    width: min(var(--max-width), calc(100% - 32px));

    margin: 48px auto 0;

    padding: 30px 0 50px;

    border-top: 1px solid var(--border);

    color: var(--muted);

    font-size: 0.9rem;
}

.site-footer a {
    color: var(--muted);

    text-decoration: none;
}

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

.site-footer p {
    margin: 16px 0 0;
}


/* ---------- Mobile ---------- */

@media (max-width: 600px) {

    .site-header {
        padding-top: 42px;
    }

    .tool-row {
        grid-template-columns: 1fr;
    }

    .tool summary {
        padding: 0 16px;
    }

    .tool-content {
        padding: 20px 16px 22px;
    }
}