:root {
    --bg-color: #0f172a;
    --text-color: #e2e8f0;
    --accent-color: #38bdf8;
    --accent-glow: rgba(56, 189, 248, 0.5);
    
    --frame-dark: #1f140d;
    --frame-light: #4a2e1b;
    --frame-border: #6d4223;
    
    --bead-color: #f59e0b;
    --bead-shadow: #b45309;
    --bead-highlight: #fde68a;
    
    --rod-color: #94a3b8;
    --rod-shadow: #334155;
    
    --reckoning-bar: #3d2516;
}

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

body {
    font-family: 'Inter', sans-serif;
    background: radial-gradient(circle at center, #1e293b 0%, var(--bg-color) 100%);
    color: var(--text-color);
    min-height: 100vh;
    display: flex;
    flex-direction: column;
    margin: 0;
}

.main-content {
    flex: 1;
    display: flex;
    justify-content: center;
    align-items: center;
    padding: 40px 20px;
}

.app-wrapper {
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: 40px;
    padding: 40px;
    background: rgba(30, 41, 59, 0.6);
    border: 1px solid rgba(255, 255, 255, 0.1);
    border-radius: 24px;
    box-shadow: 0 25px 50px -12px rgba(0, 0, 0, 0.7), inset 0 1px 1px rgba(255, 255, 255, 0.1);
    backdrop-filter: blur(16px);
    -webkit-backdrop-filter: blur(16px);
    transform: scale(0.8);
    transform-origin: top center;
}

.app-header {
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: 20px;
    width: 100%;
}

.title {
    font-family: 'Orbitron', sans-serif;
    font-size: 2.5rem;
    font-weight: 700;
    letter-spacing: 0.1em;
    background: linear-gradient(135deg, #e0f2fe 0%, #38bdf8 100%);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    text-shadow: 0 0 30px var(--accent-glow);
    text-transform: uppercase;
}

.display-container {
    background: #020617;
    border: 2px solid #1e293b;
    border-radius: 12px;
    padding: 15px 40px;
    min-width: 300px;
    text-align: right;
    box-shadow: inset 0 0 20px rgba(0, 0, 0, 0.8), 0 0 15px var(--accent-glow);
    position: relative;
    overflow: hidden;
}

.display-container::before {
    content: '';
    position: absolute;
    top: 0; left: 0; right: 0; bottom: 0;
    background: linear-gradient(180deg, rgba(255,255,255,0.05) 0%, transparent 50%, rgba(0,0,0,0.2) 100%);
    pointer-events: none;
}

.display-value {
    font-family: 'Orbitron', monospace;
    font-size: 3.5rem;
    font-weight: 700;
    color: var(--accent-color);
    text-shadow: 0 0 10px var(--accent-glow), 0 0 20px var(--accent-glow);
    letter-spacing: 0.05em;
}

.reset-button {
    background: linear-gradient(145deg, #1e293b, #0f172a);
    color: #94a3b8;
    border: 1px solid #334155;
    padding: 12px 32px;
    border-radius: 8px;
    font-family: 'Orbitron', sans-serif;
    font-size: 1rem;
    font-weight: 700;
    letter-spacing: 0.1em;
    text-transform: uppercase;
    cursor: pointer;
    transition: all 0.3s ease;
    box-shadow: 4px 4px 10px rgba(0,0,0,0.5), -2px -2px 10px rgba(255,255,255,0.05);
}

.reset-button:hover {
    color: var(--accent-color);
    border-color: var(--accent-color);
    box-shadow: 0 0 15px var(--accent-glow), inset 0 0 10px rgba(56, 189, 248, 0.2);
}

.reset-button:active {
    transform: translateY(2px);
    box-shadow: 0 0 5px var(--accent-glow);
}

.abacus-section {
    perspective: 1000px;
}

.abacus-frame {
    position: relative;
    background: linear-gradient(to right, var(--frame-dark), var(--frame-light), var(--frame-dark));
    border: 16px solid var(--frame-border);
    border-radius: 12px;
    padding: 10px 20px;
    box-shadow: 
        inset 0 0 30px rgba(0,0,0,0.8),
        0 20px 40px rgba(0,0,0,0.8),
        0 0 0 2px #26160d;
    transform-style: preserve-3d;
    transform: rotateX(5deg);
}

/* Wood grain effect */
.frame-texture {
    position: absolute;
    top: 0; left: 0; right: 0; bottom: 0;
    opacity: 0.15;
    background-image: repeating-linear-gradient(
        45deg,
        transparent,
        transparent 5px,
        #000 5px,
        #000 10px
    );
    pointer-events: none;
    border-radius: 4px;
}

.reckoning-bar {
    position: absolute;
    top: 32%; /* Positioned above middle to give space for 4 lower beads */
    left: -16px;
    right: -16px;
    height: 18px;
    background: linear-gradient(to bottom, #5a3821, #2e1a0d);
    box-shadow: 0 5px 10px rgba(0,0,0,0.6), inset 0 2px 2px rgba(255,255,255,0.1);
    z-index: 10;
    border-top: 1px solid #7d4d2f;
    border-bottom: 1px solid #1a0e07;
}

/* Unit dots to indicate the decimal place */
.unit-dot {
    position: absolute;
    top: 32%;
    left: 50%;
    transform: translate(-50%, -50%);
    width: 8px;
    height: 8px;
    background: #fef08a;
    border-radius: 50%;
    box-shadow: 0 0 6px #fef08a, inset 0 -1px 2px rgba(0,0,0,0.5);
    z-index: 12;
}

.rods-container {
    display: flex;
    gap: 30px;
    position: relative;
    z-index: 5;
}

.rod {
    position: relative;
    width: 65px;
    height: 460px;
    display: flex;
    flex-direction: column;
    align-items: center;
}

/* The vertical stick */
.rod-stick {
    position: absolute;
    top: -10px;
    bottom: -10px;
    width: 10px;
    background: linear-gradient(to right, var(--rod-shadow), var(--rod-color), var(--rod-shadow));
    border-radius: 5px;
    box-shadow: inset 0 0 5px rgba(0,0,0,0.8), 2px 0 5px rgba(0,0,0,0.4);
    z-index: 1;
}

/* Deck areas */
.deck {
    width: 100%;
    position: relative;
    z-index: 2;
    display: flex;
    flex-direction: column;
    align-items: center;
}

.upper-deck {
    height: 32%; /* Matches reckoning bar top */
    justify-content: flex-start;
    padding-top: 10px;
}

.lower-deck {
    height: 68%; /* Below reckoning bar */
    justify-content: flex-end;
    padding-bottom: 10px;
}

.bead {
    width: 57px;
    height: 34px;
    background: linear-gradient(to bottom, var(--bead-shadow) 0%, var(--bead-color) 20%, var(--bead-highlight) 48%, var(--bead-color) 52%, var(--bead-shadow) 100%);
    clip-path: polygon(0% 50%, 50% 0%, 100% 50%, 50% 100%);
    filter: drop-shadow(0 5px 4px rgba(0,0,0,0.6));
    cursor: pointer;
    position: absolute;
    transition: transform 0.02s ease-out, filter 0.02s;
    z-index: 3;
}

.bead:hover {
    filter: brightness(1.2) drop-shadow(0 6px 6px rgba(0,0,0,0.8));
}

.bead:active {
    transition: none;
}

/* Positioning upper bead */
.bead.upper {
    top: 15px; /* Inactive position */
}

/* Active position for upper bead (moved down) */
.bead.upper.active {
    transform: translateY(90px);
}

/* Positioning lower beads */
.bead.lower {
    /* Base spacing from the bottom of the lower deck */
}

.bead.lower[data-index="0"] { bottom: 15px; }
.bead.lower[data-index="1"] { bottom: 50px; } 
.bead.lower[data-index="2"] { bottom: 85px; } 
.bead.lower[data-index="3"] { bottom: 120px; } 

/* Active positions for lower beads (moved up) */
.bead.lower.active[data-index="0"] { transform: translateY(-130px); }
.bead.lower.active[data-index="1"] { transform: translateY(-130px); }
.bead.lower.active[data-index="2"] { transform: translateY(-130px); }
.bead.lower.active[data-index="3"] { transform: translateY(-130px); }

/* Note: we use transform for animations, but the math for distance to reckoning bar is about 110px from the bottom resting position. */

/* Small screen adjustments */
@media (max-width: 800px) {
    .app-wrapper {
        transform: scale(0.8);
    }
}

@media (max-width: 500px) {
    .app-wrapper {
        transform: scale(0.6);
        padding: 20px;
    }
}