@import url("https://fonts.googleapis.com/css2?family=Space+Grotesk:wght@400;600&display=swap");

:root {
    --bg: #0c0c10;
    --panel: #14151b;
    --panel-edge: #262838;
    --text: #f4f4f6;
    --muted: #a2a7b8;
    --accent: #ff5a52;
    --canvas-bg: #050506;
    --shadow: 0 20px 50px rgba(0, 0, 0, 0.45);
}

* {
    box-sizing: border-box;
    font-family: "Space Grotesk", "Segoe UI", sans-serif;
}

html, body {
    width: 100%;
    height: 100%;
}

body {
    margin: 0;
    background: radial-gradient(1200px 800px at 20% 10%, #222433 0%, #0c0c10 55%, #07070a 100%);
    color: var(--text);
    overflow: hidden;
}

.app {
    width: 100%;
    height: 100%;
    display: grid;
    grid-template-rows: auto 1fr;
}

.topbar {
    display: flex;
    align-items: center;
    gap: 12px;
    padding: 16px 20px 8px 20px;
}

.brand {
    font-weight: 600;
    letter-spacing: 0.06em;
    text-transform: uppercase;
    font-size: 14px;
    color: var(--muted);
}

.menu-toggle {
    width: 44px;
    height: 44px;
    border-radius: 12px;
    background: var(--panel);
    border: 1px solid var(--panel-edge);
    display: grid;
    align-content: center;
    justify-items: center;
    gap: 5px;
    cursor: pointer;
    box-shadow: var(--shadow);
}

.menu-toggle span {
    width: 20px;
    height: 2px;
    background: var(--text);
    border-radius: 999px;
    display: block;
    transition: transform 0.2s ease, opacity 0.2s ease;
}

.menu-toggle.open span:nth-child(1) {
    transform: translateY(7px) rotate(45deg);
}

.menu-toggle.open span:nth-child(2) {
    opacity: 0;
}

.menu-toggle.open span:nth-child(3) {
    transform: translateY(-7px) rotate(-45deg);
}

.menu {
    position: absolute;
    top: 70px;
    left: 20px;
    width: min(280px, 80vw);
    background: var(--panel);
    border: 1px solid var(--panel-edge);
    border-radius: 16px;
    padding: 16px;
    box-shadow: var(--shadow);
    opacity: 0;
    pointer-events: none;
    transform: translateY(-8px);
    transition: opacity 0.2s ease, transform 0.2s ease;
}

.menu.open {
    opacity: 1;
    pointer-events: auto;
    transform: translateY(0);
}

.menu-section {
    display: grid;
    gap: 8px;
    margin-bottom: 14px;
    font-size: 14px;
}

.menu-section label {
    color: var(--muted);
    text-transform: uppercase;
    letter-spacing: 0.06em;
    font-size: 11px;
}

.menu-section select {
    background: #0f1118;
    border: 1px solid var(--panel-edge);
    color: var(--text);
    border-radius: 10px;
    padding: 10px 12px;
    font-size: 14px;
    outline: none;
}

.menu-section.hint {
    color: var(--muted);
    font-size: 13px;
    line-height: 1.4;
}

.stage {
    display: grid;
    place-items: center;
    padding: 16px 24px 32px;
    width: 100%;
    height: 100%;
}

#canvas {
    background: var(--canvas-bg);
    border-radius: 18px;
    box-shadow: 0 24px 70px rgba(0, 0, 0, 0.55);
    border: 1px solid rgba(255, 255, 255, 0.08);
    touch-action: none;
}

.cell {
    transition: all 0.1s ease-in-out;
    background-color: #101010;
    box-shadow: inset 0px 0px 1px 0px rgba(175, 187, 242, 0.3);
    border: 1px solid green;
}

@media (max-width: 768px) {
    .topbar {
        padding: 12px 12px 6px;
    }

    .menu {
        top: 60px;
        left: 12px;
        width: min(260px, 86vw);
    }

    #canvas {
        border-radius: 0;
        width: 100vw;
        height: 100vh;
        border: none;
    }

    .stage {
        padding: 0;
    }
}