:root {
    --bg-color: #0f1115;
    --panel-bg: #1a1e26;
    --text-primary: #f8fafc;
    --text-secondary: #94a3b8;
    --accent-primary: #e11d48; /* TUF Red */
    --accent-blue: #3b82f6;
    --accent-green: #10b981;
    --border-color: #2d3748;
    --font-family: 'Inter', system-ui, -apple-system, sans-serif;
}

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

body {
    background-color: var(--bg-color);
    color: var(--text-primary);
    font-family: var(--font-family);
    min-height: 100vh;
    display: flex;
    justify-content: center;
    padding: 2rem 1.5rem;
    line-height: 1.5;
}

.container {
    max-width: 1200px;
    width: 100%;
    display: flex;
    flex-direction: column;
    gap: 2rem;
}

header {
    text-align: center;
}

header h1 {
    font-size: 2.5rem;
    font-weight: 800;
    margin-bottom: 0.5rem;
    color: var(--text-primary);
}

header p {
    color: var(--text-secondary);
    font-size: 1.1rem;
    font-weight: 400;
}

.controls {
    background: var(--panel-bg);
    padding: 1.5rem;
    border-radius: 12px;
    border: 1px solid var(--border-color);
    display: flex;
    flex-wrap: wrap;
    gap: 1rem;
    align-items: flex-end;
    justify-content: space-between;
}

.input-group {
    display: flex;
    flex-direction: column;
    gap: 0.5rem;
}

.array-input-group {
    flex-grow: 3;
    min-width: 250px;
}

.speed-group {
    flex-grow: 1;
    min-width: 150px;
}

select#speed-dropdown {
    background: var(--bg-color);
    border: 1px solid var(--border-color);
    color: var(--text-primary);
    padding: 0.875rem 1rem;
    border-radius: 8px;
    font-family: var(--font-family);
    font-size: 1rem;
    transition: all 0.2s ease;
    cursor: pointer;
    appearance: none;
    -webkit-appearance: none;
    background-image: url("data:image/svg+xml;charset=US-ASCII,%3Csvg%20xmlns%3D%22http%3A%2F%2Fwww.w3.org%2F2000%2Fsvg%22%20width%3D%22292.4%22%20height%3D%22292.4%22%3E%3Cpath%20fill%3D%22%2394a3b8%22%20d%3D%22M287%2069.4a17.6%2017.6%200%200%200-13-5.4H18.4c-5%200-9.3%201.8-12.9%205.4A17.6%2017.6%200%200%200%200%2082.2c0%205%201.8%209.3%205.4%2012.9l128%20127.9c3.6%203.6%207.8%205.4%2012.8%205.4s9.2-1.8%2012.8-5.4L287%2095c3.5-3.5%205.4-7.8%205.4-12.8%200-5-1.9-9.2-5.5-12.8z%22%2F%3E%3C%2Fsvg%3E");
    background-repeat: no-repeat;
    background-position: right 1rem top 50%;
    background-size: 0.65rem auto;
}

select#speed-dropdown:focus {
    outline: none;
    border-color: var(--accent-primary);
}

select#speed-dropdown option {
    background: var(--panel-bg);
    color: var(--text-primary);
}

.input-group label {
    font-size: 0.875rem;
    color: var(--text-secondary);
    font-weight: 600;
    text-transform: uppercase;
    letter-spacing: 0.05em;
}

.input-group input {
    background: var(--bg-color);
    border: 1px solid var(--border-color);
    color: var(--text-primary);
    padding: 0.875rem 1rem;
    border-radius: 8px;
    font-family: 'JetBrains Mono', monospace;
    font-size: 1rem;
    transition: all 0.2s ease;
}

.input-group input:focus {
    outline: none;
    border-color: var(--accent-primary);
}

.button-group {
    display: flex;
    gap: 1rem;
    flex-wrap: wrap;
}

button {
    padding: 0.875rem 1.5rem;
    border-radius: 8px;
    font-family: var(--font-family);
    font-weight: 600;
    font-size: 1rem;
    cursor: pointer;
    transition: all 0.2s;
    border: none;
}

.primary-btn {
    background-color: var(--accent-primary);
    color: white;
}

.primary-btn:hover:not(:disabled) {
    background-color: #be123c;
    transform: translateY(-2px);
}

.primary-btn:disabled {
    opacity: 0.5;
    cursor: not-allowed;
}

.secondary-btn {
    background-color: transparent;
    color: var(--text-primary);
    border: 1px solid var(--border-color);
}

.secondary-btn:hover {
    background-color: rgba(255, 255, 255, 0.05);
}

.main-content {
    display: grid;
    grid-template-columns: 1fr;
    gap: 2rem;
}

@media (min-width: 992px) {
    .main-content {
        grid-template-columns: 3fr 2fr;
    }
}

.visualization-area {
    display: flex;
    flex-direction: column;
    gap: 1.5rem;
}

.array-container {
    display: flex;
    flex-wrap: wrap;
    gap: 0.75rem;
    justify-content: center;
    padding: 2.5rem 1.5rem;
    background: var(--panel-bg);
    border-radius: 12px;
    border: 1px solid var(--border-color);
    min-height: 200px;
    align-items: center;
}

.array-element {
    width: 55px;
    height: 55px;
    background: var(--bg-color);
    border: 2px solid var(--border-color);
    border-radius: 8px;
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 1.25rem;
    font-weight: 700;
    position: relative;
    transition: all 0.3s ease;
    color: var(--text-primary);
}

.array-element.active {
    border-color: var(--accent-primary);
    transform: translateY(-5px);
    background: var(--accent-primary);
    color: white;
}

.array-element.current-subarray {
    background: rgba(225, 29, 72, 0.15);
    border-color: var(--accent-primary);
}

.array-element.max-subarray {
    background: rgba(16, 185, 129, 0.2);
    border-color: var(--accent-green);
}

.array-element.max-subarray.active {
    background: var(--accent-green);
    border-color: var(--accent-green);
}

.array-element::after {
    content: '↑';
    position: absolute;
    bottom: -35px;
    font-size: 1.5rem;
    font-weight: 900;
    color: var(--accent-primary);
    opacity: 0;
    transform: translateY(-5px);
    transition: opacity 0.3s ease;
}

.array-element.active::after {
    opacity: 1;
    animation: bounce 1s infinite;
}

@keyframes bounce {
    0%, 100% { transform: translateY(0); }
    50% { transform: translateY(-8px); }
}

.status-panel {
    display: flex;
    flex-direction: column;
    gap: 1.5rem;
}

@media (min-width: 600px) {
    .status-panel {
        flex-direction: row;
    }
}

.status-card {
    flex: 1;
    background: var(--panel-bg);
    padding: 1.5rem;
    border-radius: 12px;
    border: 1px solid var(--border-color);
    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: center;
    transition: all 0.3s ease;
    min-height: 160px;
}

.status-label {
    font-size: 0.875rem;
    color: var(--text-secondary);
    margin-bottom: 0.5rem;
    text-transform: uppercase;
    letter-spacing: 0.1em;
    font-weight: 600;
}

.status-value {
    font-size: 3rem;
    font-weight: 800;
    line-height: 1;
    margin-bottom: 0.5rem;
    transition: all 0.3s ease;
}

.current-sum-card .status-value {
    color: var(--text-primary);
}

.max-sum-card .status-value {
    color: var(--accent-green);
}

.status-card.negative-flash {
    background: rgba(225, 29, 72, 0.1);
    border-color: var(--accent-primary);
}

.status-card.negative-flash .status-value {
    color: var(--accent-primary);
}

.status-warning {
    color: var(--accent-primary);
    font-size: 0.875rem;
    font-weight: 600;
    background: rgba(225, 29, 72, 0.15);
    padding: 4px 12px;
    border-radius: 6px;
    margin-top: 0.5rem;
    text-align: center;
    transition: all 0.3s ease;
}

.status-warning.hidden {
    display: none;
}

.status-warning.success {
    color: var(--accent-green);
    background: rgba(16, 185, 129, 0.15);
}

.status-warning.neutral {
    color: var(--text-secondary);
    background: rgba(148, 163, 184, 0.1);
}

.status-card.new-max-flash {
    background: rgba(16, 185, 129, 0.1);
    border-color: var(--accent-green);
}

.code-panel {
    background: var(--bg-color);
    border-radius: 12px;
    border: 1px solid var(--border-color);
    padding: 1.5rem;
    overflow-x: auto;
    height: 100%;
    display: flex;
    flex-direction: column;
}

pre {
    font-family: 'JetBrains Mono', 'Fira Code', Consolas, monospace;
    font-size: 0.95rem;
    line-height: 1.6;
    color: #e2e8f0;
    margin: 0;
}

code span {
    display: block;
    padding: 2px 12px;
    border-radius: 4px;
    transition: background-color 0.2s ease;
    border-left: 3px solid transparent;
}

code span.highlight {
    background-color: var(--panel-bg);
    border-left: 3px solid var(--accent-primary);
}

footer {
    text-align: center;
    padding-top: 1rem;
    border-top: 1px solid var(--border-color);
    color: var(--text-secondary);
}

footer a {
    color: var(--accent-primary);
    text-decoration: none;
    font-weight: 600;
}

footer a:hover {
    text-decoration: underline;
}