:root {
    --bg-dark: #0f172a;
    --bg-panel: #1e293b;
    --bg-input: #0f172a;
    --border: #334155;
    --text-main: #f8fafc;
    --text-muted: #94a3b8;
    --accent: #3b82f6;
    --accent-hover: #2563eb;
    --success: #10b981;
    --warning: #f59e0b;
    --danger: #ef4444;
}

* {
    box-sizing: border-box;
}

body {
    background-color: var(--bg-dark);
    color: var(--text-main);
    font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, sans-serif;
    margin: 0;
    line-height: 1.6;
}

header {
    background: var(--bg-panel);
    border-bottom: 1px solid var(--border);
    padding: 1rem 2rem;
    display: flex;
    justify-content: space-between;
    align-items: center;
}

.brand {
    font-weight: 600;
    color: #fff;
    font-size: 1.1rem;
    display: flex;
    align-items: center;
    gap: 10px;
}

.brand i {
    color: var(--accent);
}

.nav a {
    color: var(--text-muted);
    text-decoration: none;
    margin-left: 20px;
    font-size: 0.9rem;
}

.nav a:hover {
    color: var(--accent);
}

.tool-container {
    max-width: 800px;
    margin: 2rem auto;
    padding: 0 1rem;
}

.panel {
    background: var(--bg-panel);
    border: 1px solid var(--border);
    border-radius: 8px;
    padding: 1.5rem;
    margin-bottom: 1.5rem;
}

h2 {
    margin-top: 0;
    color: #fff;
    font-size: 1.1rem;
    margin-bottom: 1rem;
}

/* Permission Grid */
.perm-grid {
    display: grid;
    grid-template-columns: 100px repeat(3, 1fr);
    gap: 10px;
    align-items: center;
}

.perm-header {
    font-weight: 600;
    text-align: center;
    color: var(--accent);
    padding: 10px;
    background: var(--bg-input);
    border-radius: 6px;
}

.perm-row-label {
    font-weight: 600;
    color: var(--text-main);
    padding: 10px;
}

.perm-cell {
    display: flex;
    justify-content: center;
    gap: 8px;
    padding: 10px;
    background: var(--bg-input);
    border-radius: 6px;
}

.perm-checkbox {
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: 4px;
}

.perm-checkbox input[type="checkbox"] {
    width: 24px;
    height: 24px;
    cursor: pointer;
    accent-color: var(--accent);
}

.perm-checkbox label {
    font-size: 0.75rem;
    color: var(--text-muted);
}

/* Result Display */
.result-display {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 15px;
    margin-top: 1rem;
}

.result-box {
    background: var(--bg-input);
    border: 1px solid var(--border);
    border-radius: 8px;
    padding: 15px;
    text-align: center;
}

.result-label {
    font-size: 0.8rem;
    color: var(--text-muted);
    margin-bottom: 5px;
}

.result-value {
    font-size: 1.8rem;
    font-weight: 700;
    font-family: 'Consolas', monospace;
    color: var(--accent);
}

.result-value.symbolic {
    font-size: 1.2rem;
    letter-spacing: 2px;
}

/* Octal Input */
.octal-input-row {
    display: flex;
    gap: 10px;
    align-items: center;
    margin-top: 1rem;
}

.octal-input-row input {
    width: 120px;
    padding: 12px;
    font-size: 1.5rem;
    font-family: 'Consolas', monospace;
    text-align: center;
    background: var(--bg-input);
    border: 1px solid var(--border);
    border-radius: 6px;
    color: var(--text-main);
}

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

.octal-input-row span {
    color: var(--text-muted);
    font-size: 0.9rem;
}

/* Commands */
.command-box {
    background: var(--bg-input);
    border: 1px solid var(--border);
    border-radius: 6px;
    padding: 12px 15px;
    font-family: 'Consolas', monospace;
    font-size: 0.9rem;
    color: var(--success);
    display: flex;
    justify-content: space-between;
    align-items: center;
    margin-top: 10px;
}

.copy-btn {
    background: transparent;
    border: 1px solid var(--border);
    color: var(--text-muted);
    padding: 5px 10px;
    border-radius: 4px;
    cursor: pointer;
    font-size: 0.8rem;
}

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

/* Common Permissions */
.common-perms {
    display: flex;
    flex-wrap: wrap;
    gap: 8px;
    margin-top: 1rem;
}

.common-btn {
    background: var(--bg-input);
    border: 1px solid var(--border);
    color: var(--text-muted);
    padding: 8px 12px;
    border-radius: 4px;
    cursor: pointer;
    font-size: 0.85rem;
    font-family: 'Consolas', monospace;
}

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

.common-btn span {
    font-size: 0.75rem;
    color: var(--text-muted);
    margin-left: 5px;
}