@import url('https://fonts.googleapis.com/css2?family=JetBrains+Mono:wght@400;700&family=Outfit:wght@400;700&family=Space+Grotesk:wght@700&display=swap');

:root {
    --bg-dark: #020617;
    --panel-dark: rgba(15, 23, 42, 0.8);
    --accent-cyan: #22d3ee;
    --accent-blue: #3b82f6;
    --accent-purple: #a855f7;
    --accent-green: #4ade80;
    --accent-amber: #fbbf24;
    --text-primary: #f8fafc;
    --text-secondary: #94a3b8;
    --text-muted: #475569;
    --border-soft: rgba(255, 255, 255, 0.08);
    --border-active: rgba(34, 211, 238, 0.3);
}

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

body.sim-page {
    font-family: 'Outfit', sans-serif;
    color: var(--text-primary);
    background-color: #000;
    line-height: 1.5;
    width: 100%; height: 100%;
    margin: 0; padding: 0;
    overflow: hidden;
}

#phet-stage {
    position: absolute; top: 0; left: 0;
    width: 1280px; height: 720px;
    background-color: var(--bg-dark);
    overflow: hidden; transform-origin: 0 0;
    box-shadow: 0 0 50px rgba(0, 0, 0, 0.4);
    touch-action: none;
    display: flex; flex-direction: column;
}

#bgCanvas {
    position: absolute; top:0; left:0; width:100% !important; height:100% !important;
    opacity: 0.4;
    filter: blur(2px);
    z-index: 0;
}

/* Compact Nav for this page */
nav {
    padding: 0.55rem 1.5rem !important;
    min-height: unset !important;
    position: relative; z-index: 10;
    height: 60px;
    flex-shrink: 0;
}

nav .logo {
    font-size: 1rem !important;
}

nav .logo .icon {
    font-size: 1.1rem !important;
}

nav .nav-center {
    font-size: 0.82rem !important;
}

nav .btn {
    padding: 0.35rem 1rem !important;
    font-size: 0.8rem !important;
}

.sim-main {
    padding: 10px 20px 20px;
    height: 660px;
    display: flex;
    flex-direction: column;
    position: relative;
    z-index: 5;
    flex-grow: 1;
}

/* Cycle Phase Nav - Ultra Compact */
.dashboard-header {
    display: flex;
    justify-content: center;
    gap: 1.5rem;
    margin-bottom: 0.8rem;
    padding: 0.6rem;
    background: rgba(30, 41, 59, 0.5);
    backdrop-filter: blur(12px);
    border-radius: 12px;
    border: 1px solid var(--border-soft);
    box-shadow: 0 4px 20px rgba(0, 0, 0, 0.3);
}

.phase-indicator {
    display: flex;
    align-items: center;
    gap: 0.5rem;
    opacity: 0.25;
    transition: all 0.4s cubic-bezier(0.175, 0.885, 0.32, 1.275);
    padding: 0.2rem 0.8rem;
    border-radius: 8px;
}

.phase-indicator.active {
    opacity: 1;
    background: rgba(255, 255, 255, 0.03);
}

.phase-icon {
    width: 28px;
    height: 28px;
    border-radius: 6px;
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 0.8rem;
    background: rgba(15, 23, 42, 0.6);
    border: 1px solid var(--border-soft);
}

#phase-fetch.active .phase-icon {
    color: var(--accent-cyan);
    border-color: var(--accent-cyan);
    box-shadow: 0 0 10px var(--accent-cyan);
}

#phase-decode.active .phase-icon {
    color: var(--accent-purple);
    border-color: var(--accent-purple);
    box-shadow: 0 0 10px var(--accent-purple);
}

#phase-execute.active .phase-icon {
    color: var(--accent-green);
    border-color: var(--accent-green);
    box-shadow: 0 0 10px var(--accent-green);
}

#phase-store.active .phase-icon {
    color: var(--accent-amber);
    border-color: var(--accent-amber);
    box-shadow: 0 0 10px var(--accent-amber);
}

.phase-label {
    font-size: 0.75rem;
    font-weight: 800;
    letter-spacing: 1px;
    font-family: 'Space Grotesk', sans-serif;
}

/* Layout Architecture */
.simulation-layout {
    display: grid;
    grid-template-columns: 220px 1fr 300px;
    gap: 0.8rem;
    flex: 1;
}

/* RAM Memory Panel */
.memory-unit {
    background: var(--panel-dark);
    border: 1px solid var(--border-soft);
    border-radius: 16px;
    padding: 0.8rem;
    display: flex;
    flex-direction: column;
    height: 520px;
}

.memory-title {
    font-size: 0.8rem;
    font-weight: 700;
    color: var(--accent-cyan);
    margin-bottom: 0.8rem;
    text-transform: uppercase;
    display: flex;
    align-items: center;
    gap: 8px;
}

.memory-list {
    overflow-y: auto;
    flex: 1;
    padding-right: 4px;
    scrollbar-width: thin;
    scrollbar-color: var(--accent-cyan) transparent;
}

.memory-list::-webkit-scrollbar {
    width: 4px;
}
.memory-list::-webkit-scrollbar-track {
    background: transparent;
}
.memory-list::-webkit-scrollbar-thumb {
    background: rgba(34, 211, 238, 0.3);
    border-radius: 10px;
}

.mem-cell {
    display: flex;
    background: rgba(2, 6, 23, 0.4);
    border: 1px solid var(--border-soft);
    border-radius: 6px;
    margin-bottom: 4px;
    transition: all 0.3s;
}

.mem-cell.active-mem {
    border-color: var(--accent-cyan);
    background: rgba(34, 211, 238, 0.15);
    box-shadow: inset 0 0 10px rgba(34, 211, 238, 0.1);
}

.cell-addr {
    width: 35px;
    background: rgba(15, 23, 42, 0.6);
    color: var(--text-muted);
    font-family: 'JetBrains Mono', monospace;
    font-size: 0.7rem;
    display: flex;
    align-items: center;
    justify-content: center;
    border-right: 1px solid var(--border-soft);
}

.cell-content {
    flex: 1;
    padding: 0.4rem;
    display: flex;
    flex-direction: column;
}

.cell-content .val {
    font-family: 'JetBrains Mono', monospace;
    font-weight: 700;
    color: #fff;
    font-size: 0.85rem;
}

.cell-content .lbl {
    font-size: 0.6rem;
    color: var(--text-muted);
    font-style: italic;
}

/* CPU Core Panel */
.cpu-architecture {
    display: flex;
    flex-direction: column;
    gap: 0.8rem;
}

.cpu-frame {
    background: linear-gradient(135deg, #0f172a 0%, #020617 100%);
    border: 2px solid #334155;
    border-radius: 20px;
    padding: 1rem;
    position: relative;
    box-shadow: inset 0 0 30px rgba(0, 0, 0, 0.8), 0 10px 30px rgba(0, 0, 0, 0.5);
}

.cpu-title {
    position: absolute;
    top: -10px;
    left: 20px;
    background: #020617;
    padding: 0 10px;
    font-size: 0.6rem;
    font-weight: 800;
    color: var(--accent-cyan);
    letter-spacing: 2px;
}

.registers-grid {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 0.8rem;
}

.register {
    background: rgba(30, 41, 59, 0.4);
    border: 1px solid var(--border-soft);
    border-radius: 10px;
    padding: 0.5rem;
    display: flex;
    flex-direction: column;
    align-items: center;
    transition: all 0.3s cubic-bezier(0.175, 0.885, 0.32, 1.275);
    min-height: 65px;
}

.register.active-reg {
    border-color: var(--accent-cyan);
    background: rgba(34, 211, 238, 0.08);
    transform: translateY(-2px);
    box-shadow: 0 4px 12px rgba(34, 211, 238, 0.15);
}

.reg-label {
    font-size: 0.6rem;
    font-weight: 800;
    color: var(--text-muted);
    text-transform: uppercase;
    margin-bottom: 2px;
}

.reg-value {
    font-family: 'JetBrains Mono', monospace;
    font-size: 1.1rem;
    font-weight: 700;
    color: #fff;
    text-shadow: 0 0 10px rgba(255, 255, 255, 0.1);
}

.reg-desc {
    font-size: 0.55rem;
    color: var(--text-muted);
    text-align: center;
}

.register.accent {
    border-top: 2px solid var(--accent-green);
}

/* ALU Component */
.alu-block {
    margin-top: 1rem;
    padding: 0.8rem;
    border: 1px solid rgba(255, 255, 255, 0.03);
    background: rgba(255, 255, 255, 0.02);
    border-radius: 15px;
    display: flex;
    align-items: center;
    justify-content: center;
    gap: 1.2rem;
}

.alu-shape {
    width: 80px;
    height: 80px;
    clip-path: polygon(0% 0%, 40% 0%, 50% 15%, 60% 0%, 100% 0%, 80% 100%, 20% 100%);
    background: linear-gradient(135deg, #1e293b, #0f172a);
    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: center;
    border: 1px solid #334155;
    position: relative;
    z-index: 2;
}

.alu-visual.pulse .alu-shape {
    animation: alu-glow 0.8s infinite alternate;
}

@keyframes alu-glow {
    from {
        border-color: #334155;
        box-shadow: 0 0 0 transparent;
    }

    to {
        border-color: var(--accent-green);
        box-shadow: 0 0 20px rgba(74, 222, 128, 0.3);
    }
}

.alu-text {
    font-size: 0.7rem;
    font-weight: 800;
    opacity: 0.4;
    letter-spacing: 2px;
}

.alu-op {
    font-size: 1.4rem;
    font-weight: 900;
    color: var(--accent-green);
    margin-top: -5px;
}

.alu-in,
.alu-out-val {
    background: #020617;
    border: 1px solid var(--border-soft);
    border-radius: 6px;
    padding: 0.2rem 0.6rem;
    font-family: 'JetBrains Mono', monospace;
    font-size: 0.95rem;
    color: #fff;
    min-width: 45px;
    text-align: center;
}

.alu-out-val {
    color: var(--accent-amber);
    border-color: rgba(251, 191, 36, 0.4);
}

/* Control Panel (Right) */
.control-center {
    display: flex;
    flex-direction: column;
    gap: 0.8rem;
}

.card-box {
    background: var(--panel-dark);
    border: 1px solid var(--border-soft);
    border-radius: 16px;
    padding: 1rem;
}

.input-panel h3 {
    font-size: 0.9rem;
    margin-bottom: 0.5rem;
    color: var(--text-secondary);
}

#problem-input {
    width: 100%;
    background: #020617;
    border: 1px solid var(--border-soft);
    border-radius: 8px;
    padding: 0.6rem;
    color: #fff;
    font-family: inherit;
    font-size: 0.9rem;
    margin-bottom: 0.6rem;
}

.example-pills {
    display: flex;
    gap: 0.5rem;
}

.pill {
    font-size: 0.65rem;
    padding: 0.2rem 0.6rem;
    background: rgba(255, 255, 255, 0.05);
    border: 1px solid var(--border-soft);
    border-radius: 50px;
    cursor: pointer;
    transition: 0.3s;
}

.pill:hover {
    background: var(--accent-cyan);
    color: #020617;
    border-color: var(--accent-cyan);
}

.playback-controls {
    display: flex;
    flex-direction: column;
    gap: 0.4rem;
}

.btn-ctrl {
    width: 100%;
    padding: 0.5rem;
    border-radius: 8px;
    font-weight: 700;
    font-size: 0.8rem;
    cursor: pointer;
    display: flex;
    align-items: center;
    justify-content: center;
    gap: 0.5rem;
    transition: 0.3s;
    border: 1px solid transparent;
}

.btn-primary {
    background: var(--accent-blue);
    color: #fff;
}

.btn-primary:hover {
    background: #2563eb;
    transform: translateY(-1px);
}

.btn-outline {
    background: transparent;
    color: var(--text-secondary);
    border-color: var(--border-soft);
}

.btn-outline:hover {
    border-color: var(--accent-cyan);
    color: var(--accent-cyan);
}

#play-pause.running {
    background: #ef4444;
}

.educational-panel {
    flex: 1;
    display: flex;
    flex-direction: column;
}

.insight-badge {
    background: rgba(34, 211, 238, 0.1);
    color: var(--accent-cyan);
    font-size: 0.6rem;
    font-weight: 800;
    padding: 0.2rem 0.6rem;
    border-radius: 4px;
    width: fit-content;
    margin-bottom: 0.6rem;
    letter-spacing: 1px;
}

#cycle-description {
    font-size: 0.8rem;
    color: #cbd5e1;
    font-style: italic;
    line-height: 1.4;
}

/* Final Result Banner - overlays the step log, no layout shift */
#result-banner {
    position: absolute;
    bottom: 0;
    left: 0;
    right: 0;
    background: linear-gradient(135deg, rgba(2, 6, 23, 0.92), rgba(15, 23, 42, 0.97));
    border-top: 2px solid rgba(74, 222, 128, 0.6);
    border-radius: 0 0 10px 10px;
    padding: 0.8rem 1rem;
    text-align: center;
    animation: result-slide-up 0.4s cubic-bezier(0.175, 0.885, 0.32, 1.275);
    z-index: 10;
}

@keyframes result-slide-up {
    from {
        transform: translateY(100%);
        opacity: 0;
    }

    to {
        transform: translateY(0);
        opacity: 1;
    }
}

@keyframes result-fade-out {
    from {
        opacity: 1;
        transform: translateY(0);
    }

    to {
        opacity: 0;
        transform: translateY(10px);
    }
}

#result-banner.fade-out {
    animation: result-fade-out 1s ease forwards;
}

.result-label {
    font-size: 0.65rem;
    font-weight: 800;
    color: var(--accent-green);
    letter-spacing: 1px;
    margin-bottom: 0.3rem;
}

.result-value {
    font-family: 'JetBrains Mono', monospace;
    font-size: 2rem;
    font-weight: 900;
    color: #fff;
    text-shadow: 0 0 20px rgba(74, 222, 128, 0.7);
}

/* Step Log inside CPU Frame */
.step-log {
    margin-top: 0.8rem;
    border-top: 1px solid var(--border-soft);
    padding-top: 0.6rem;
    max-height: 120px;
    display: flex;
    flex-direction: column;
    position: relative;
    /* needed so banner can overlay */
    overflow: hidden;
}

.step-log-header {
    display: flex;
    gap: 0.5rem;
    padding: 0.2rem 0.5rem;
    font-size: 0.6rem;
    font-weight: 800;
    color: var(--text-muted);
    letter-spacing: 1px;
    border-bottom: 1px solid var(--border-soft);
    margin-bottom: 0.3rem;
}

.step-col-phase {
    width: 110px;
    flex-shrink: 0;
}

.step-col-action {
    flex: 1;
}

.step-log-body {
    overflow-y: auto;
    flex: 1;
}

.step-log-body::-webkit-scrollbar {
    width: 2px;
}

.step-log-body::-webkit-scrollbar-thumb {
    background: #334155;
}

.step-row {
    display: flex;
    gap: 0.5rem;
    padding: 0.2rem 0.5rem;
    font-size: 0.72rem;
    border-radius: 4px;
    transition: background 0.2s;
}

.step-row.active-row {
    background: rgba(34, 211, 238, 0.08);
    border-left: 2px solid var(--accent-cyan);
}

.step-row .step-phase {
    width: 110px;
    flex-shrink: 0;
    font-family: 'JetBrains Mono', monospace;
    font-weight: 700;
    font-size: 0.68rem;
}

.step-row .step-action {
    flex: 1;
    color: #cbd5e1;
    font-family: 'JetBrains Mono', monospace;
    font-size: 0.68rem;
}

/* Phase color coding */
.step-row.phase-fetch .step-phase {
    color: var(--accent-cyan);
}

.step-row.phase-decode .step-phase {
    color: var(--accent-purple);
}

.step-row.phase-execute .step-phase {
    color: var(--accent-green);
}

.step-row.phase-store .step-phase {
    color: var(--accent-amber);
}

.memory-list::-webkit-scrollbar {
    width: 3px;
}

.memory-list::-webkit-scrollbar-thumb {
    background: #334155;
    border-radius: 10px;
}

/* Responsive Adjustments */

/* Pipeline UI */
.pipeline-panel {
    border-color: rgba(168, 85, 247, 0.2);
    background: linear-gradient(135deg, rgba(15, 23, 42, 0.8), rgba(88, 28, 135, 0.05));
}

.header-with-badge {
    display: flex;
    justify-content: space-between;
    align-items: center;
    margin-bottom: 0.5rem;
}

.header-with-badge h3 {
    font-size: 0.9rem;
    color: var(--accent-purple);
}

.badge-new {
    font-size: 0.55rem;
    background: var(--accent-purple);
    color: #fff;
    padding: 2px 6px;
    border-radius: 4px;
    font-weight: 800;
}

.pipeline-view {
    display: none;
    margin-top: 1rem;
    gap: 10px;
    animation: fadeIn 0.3s ease;
}

.pipeline-view.active {
    display: flex;
    flex-direction: column;
}

@keyframes fadeIn {
    from { opacity: 0; transform: translateY(5px); }
    to { opacity: 1; transform: translateY(0); }
}