/* ===== A* WIDGET — SAE STYLE =====
   Sober palette aligned on sae_styles.css: white background, SAE black for
   text, SAE red as the single accent. Algorithm states use a monochrome
   grey scale and the red accent to stay on brand. */

@import url("https://fonts.googleapis.com/css2?family=Inter:wght@400;500;600;700;800&family=JetBrains+Mono:wght@400;500;700&display=swap");

:root {
    --sae-red: #E30613;
    --sae-black: #1a1a1a;
    --sae-white: #ffffff;
    --sae-gray: #888888;
    --sae-code-bg: #2d2d2d;

    /* Surfaces */
    --bg: var(--sae-white);
    --panel: #ffffff;
    --panel2: #f5f5f5;
    --line: #e2e2e2;
    --line-soft: #ececec;

    /* Text */
    --text: var(--sae-black);
    --muted: #555555;
    --muted2: var(--sae-gray);

    /* A* state colors (sober: greys + SAE red as accent) */
    --start: var(--sae-black);
    --goal: var(--sae-red);
    --wall: var(--sae-black);
    --open: #c7c7c7;        /* frontier — light grey */
    --closed: #9a9a9a;      /* visited — medium grey */
    --current: var(--sae-red);
    --path: var(--sae-red);

    --shadow: 0 1px 2px rgba(26, 26, 26, .04), 0 4px 12px rgba(26, 26, 26, .06);
    --radius: 6px;
}

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

html, body {
    background: var(--bg);
    color: var(--text);
    font-family: "Inter", "Segoe UI", system-ui, sans-serif;
    min-height: 100vh;
}

.wrap { max-width: 1180px; margin: 0 auto; padding: 28px 22px 60px; }

/* ===== HEADER ===== */
header {
    display: flex; align-items: flex-end; justify-content: space-between;
    gap: 20px; flex-wrap: wrap; margin-bottom: 22px;
    padding-bottom: 16px; border-bottom: 3px solid var(--sae-red);
}
h1 {
    font-family: "Inter", system-ui, sans-serif;
    font-weight: 800; font-size: clamp(26px, 3.4vw, 38px);
    letter-spacing: -.01em; line-height: 1; text-transform: uppercase;
    color: var(--sae-black);
}
h1 .star { color: var(--sae-red); }
.sub { color: var(--muted); font-size: 14px; margin-top: 8px; max-width: 560px; line-height: 1.5; }
.formula {
    font-family: "JetBrains Mono", monospace;
    background: var(--panel2); border: 1px solid var(--line);
    border-radius: var(--radius); padding: 10px 14px; font-size: 13px;
    white-space: nowrap; color: var(--text);
}
.formula b { color: var(--sae-red); }
.formula .g, .formula .h { color: var(--sae-black); font-weight: 600; }

/* ===== TOOLBAR ===== */
.toolbar {
    display: flex; gap: 10px; flex-wrap: wrap; align-items: center;
    background: var(--panel); border: 1px solid var(--line);
    border-radius: var(--radius); padding: 12px; margin-bottom: 18px;
    box-shadow: var(--shadow);
}
.group {
    display: flex; gap: 6px; align-items: center;
    padding: 0 10px; border-right: 1px solid var(--line-soft);
}
.group:last-child { border-right: none; }
.group-label {
    font-size: 10px; text-transform: uppercase; letter-spacing: .1em;
    color: var(--muted2); margin-right: 4px; font-weight: 600;
}

button {
    font-family: "Inter", sans-serif; font-weight: 500; font-size: 13px;
    color: var(--text); background: var(--panel);
    border: 1px solid var(--line); border-radius: var(--radius);
    padding: 7px 12px; cursor: pointer;
    transition: background .12s, border-color .12s, color .12s;
    display: flex; align-items: center; gap: 6px;
}
button:hover { border-color: var(--sae-black); }
button.on { background: var(--sae-black); color: var(--sae-white); border-color: var(--sae-black); }
button.primary { background: var(--sae-red); color: var(--sae-white); border-color: var(--sae-red); }
button.primary:hover { filter: brightness(.92); }
button.ghost { background: transparent; }
button:disabled { opacity: .4; cursor: not-allowed; }

.dot { width: 9px; height: 9px; border-radius: 2px; border: 1px solid var(--line); }
.speed { display: flex; align-items: center; gap: 8px; font-size: 12px; color: var(--muted); }
input[type=range] { accent-color: var(--sae-red); width: 90px; }
.toggle { display: flex; align-items: center; gap: 7px; font-size: 13px; color: var(--muted); cursor: pointer; user-select: none; }
.toggle input { accent-color: var(--sae-red); width: 15px; height: 15px; }

/* ===== STAGE ===== */
.stage { display: grid; grid-template-columns: 1fr 320px; gap: 18px; align-items: start; }
@media (max-width: 880px) { .stage { grid-template-columns: 1fr; } }

.board-card {
    background: var(--panel); border: 1px solid var(--line);
    border-radius: var(--radius); padding: 18px;
    box-shadow: var(--shadow); overflow: auto;
}
#grid { display: grid; gap: 2px; margin: 0 auto; width: max-content; }

/* ===== CELLS ===== */
.cell {
    position: relative; background: var(--panel2);
    border: 1px solid var(--line-soft); border-radius: 3px;
    cursor: pointer; display: flex; align-items: center; justify-content: center;
    transition: background .15s, box-shadow .15s, border-color .15s;
    user-select: none;
}
.cell .g, .cell .h {
    position: absolute; top: 2px;
    font-family: "JetBrains Mono", monospace; font-size: 9px;
    font-weight: 500; line-height: 1; opacity: .85;
}
.cell .g { left: 3px; color: var(--muted); }
.cell .h { right: 3px; color: var(--muted); }
.cell .f {
    font-family: "JetBrains Mono", monospace;
    font-size: 12px; font-weight: 700; color: var(--text); margin-top: 4px;
}
.cell .arrow {
    position: absolute; font-size: 10px; color: var(--muted2);
    bottom: 1px; left: 50%; transform: translateX(-50%); line-height: 1;
}

.cell.wall { background: var(--wall); border-color: var(--wall); cursor: pointer; }
.cell.wall .g, .cell.wall .h, .cell.wall .f, .cell.wall .arrow { display: none; }

.cell.open { background: #efefef; border-color: #cfcfcf; }
.cell.closed { background: #dcdcdc; border-color: #bdbdbd; }
.cell.current {
    background: color-mix(in srgb, var(--sae-red) 18%, var(--sae-white));
    border-color: var(--sae-red);
    box-shadow: 0 0 0 1px var(--sae-red);
    z-index: 2;
}
.cell.current .f { color: var(--sae-red); }
.cell.path {
    background: color-mix(in srgb, var(--sae-red) 22%, var(--sae-white));
    border-color: var(--sae-red);
}
.cell.path .arrow { color: var(--sae-red); opacity: 1; font-weight: 700; }

.cell.start { background: var(--sae-black) !important; border-color: var(--sae-black) !important; }
.cell.goal { background: var(--sae-red) !important; border-color: var(--sae-red) !important; }
.cell.start .badge, .cell.goal .badge {
    font-family: "Inter", sans-serif; font-weight: 800; font-size: 15px;
    color: var(--sae-white);
}
.cell.start .g, .cell.start .h, .cell.start .f, .cell.start .arrow,
.cell.goal .g, .cell.goal .h, .cell.goal .f { display: none; }

/* ===== SIDE PANELS ===== */
.side { display: flex; flex-direction: column; gap: 14px; }
.card {
    background: var(--panel); border: 1px solid var(--line);
    border-radius: var(--radius); padding: 16px; box-shadow: var(--shadow);
}
.card h3 {
    font-family: "Inter", sans-serif; font-size: 12px;
    font-weight: 700; text-transform: uppercase; letter-spacing: .1em;
    color: var(--sae-red); margin-bottom: 12px;
    padding-bottom: 8px; border-bottom: 1px solid var(--line);
}
.legend { display: grid; grid-template-columns: 1fr 1fr; gap: 9px 12px; font-size: 12.5px; }
.legend div { display: flex; align-items: center; gap: 8px; color: var(--text); }
.sw { width: 16px; height: 16px; border-radius: 3px; flex-shrink: 0; border: 1px solid var(--line); }

.stats { display: grid; grid-template-columns: 1fr 1fr; gap: 10px; }
.stat {
    background: var(--panel2); border: 1px solid var(--line-soft);
    border-radius: var(--radius); padding: 10px 12px;
}
.stat .k {
    font-size: 10px; text-transform: uppercase; letter-spacing: .08em;
    color: var(--muted2); font-weight: 600;
}
.stat .v {
    font-family: "JetBrains Mono", monospace;
    font-size: 19px; font-weight: 700; margin-top: 2px; color: var(--sae-black);
}

#narr { font-size: 13.5px; line-height: 1.55; color: var(--text); min-height: 74px; }
#narr .tag {
    display: inline-block; font-family: "JetBrains Mono", monospace;
    font-size: 10.5px; font-weight: 700; padding: 2px 8px;
    border-radius: 3px; margin-bottom: 8px; text-transform: uppercase;
    letter-spacing: .04em;
}
#narr ul { margin: 6px 0 0 16px; color: var(--muted); font-size: 12.5px; }
#narr li { margin: 3px 0; }
#narr code, .hint code {
    font-family: "JetBrains Mono", monospace;
    color: var(--sae-red); background: var(--panel2);
    padding: 1px 5px; border-radius: 3px; font-size: .92em;
}
.hint { font-size: 12px; color: var(--muted2); margin-top: 10px; line-height: 1.5; }