:root {
    --font-main: 'Space Grotesk', sans-serif;
}

* {
    box-sizing: border-box;
    margin: 0;
    padding: 0;
    -webkit-tap-highlight-color: transparent;
}

body {
    font-family: var(--font-main);
    background-color: #111;
    color: #fff;
    height: 100vh;
    height: 100dvh;
    overflow: hidden;
    display: flex;
    justify-content: center;
}

#app {
    width: 100%;
    max-width: 500px;
    height: 100%;
    display: flex;
    flex-direction: column;
    background: #000;
    position: relative;
    box-shadow: 0 0 50px rgba(255, 0, 255, 0.2);
}

.pop-header {
    padding: 20px;
    text-align: center;
    background: #000;
    border-bottom: 4px solid #fff;
    z-index: 10;
}

.pop-header h1 {
    font-size: 2.8rem;
    font-weight: 900;
    letter-spacing: 2px;
    margin-bottom: 4px;
    text-transform: uppercase;
    text-shadow: 3px 3px 0 #FF0055, -3px -3px 0 #00FFFF;
}

.pop-header p {
    font-size: 0.9rem;
    font-weight: 700;
    color: #aaa;
    text-transform: uppercase;
    letter-spacing: 2px;
}

.warhol-grid {
    flex: 1;
    display: grid;
    grid-template-columns: repeat(2, 1fr);
    grid-template-rows: repeat(3, 1fr);
    gap: 4px;
    background: #fff;
    padding: 4px;
    overflow: hidden;
}

.panel {
    position: relative;
    background-color: var(--bg-color, #ff00ff);
    overflow: hidden;
    cursor: pointer;
    display: flex;
    align-items: center;
    justify-content: center;
}

.panel img {
    width: 100%;
    height: 100%;
    object-fit: cover;
    mix-blend-mode: multiply; /* Keeps black outlines, turns white into bg color */
    user-select: none;
    -webkit-user-drag: none;
    transition: transform 0.1s cubic-bezier(0.4, 0, 0.2, 1);
}

/* 50% chance in JS to apply this class for white outlines instead of black */
.panel.inverted img {
    filter: invert(1);
    mix-blend-mode: screen; /* Keeps white outlines, turns black into bg color */
}

.panel:active img {
    transform: scale(0.92);
}

.controls {
    padding: 24px;
    background: #000;
    border-top: 4px solid #fff;
    display: flex;
    justify-content: center;
}

#randomize-btn {
    width: 100%;
    padding: 16px;
    background: #fff;
    color: #000;
    border: none;
    font-family: inherit;
    font-size: 1.2rem;
    font-weight: 900;
    text-transform: uppercase;
    letter-spacing: 2px;
    cursor: pointer;
    transition: all 0.1s;
    box-shadow: 6px 6px 0 #FF0055;
    border-radius: 0;
}

#randomize-btn:active {
    transform: translate(6px, 6px);
    box-shadow: 0px 0px 0 #FF0055;
}