:root {
    /* Light Theme (Warmer White and Red) */
    --bg-primary: #f8f8f4; /* Main background: Slightly warmer off-white */
    --bg-secondary: #f0f4f8; /* Light grey for secondary background/content areas */
    --bg-tertiary: #e2e8f0; /* Slightly darker light grey */
    --bg-card: rgba(255, 255, 255, 0.95); /* Card background */
    --bg-accent: rgba(239, 68, 68, 0.1); /* Red accent background */
    --text-primary: #1e293b;
    --text-secondary: #4b5563;
    --text-muted: #6b7280;
    --border-color: #cbd5e1; /* Neutral light grey border */
    --accent-primary: #ef4444; /* Red */
    --accent-secondary: #dc2626; /* Darker Red */
    --accent-hover: #b91c1c; /* Even Darker Red */
    --success-color: #10b981;
    --danger-color: #ef4444;
    --warning-color: #f59e0b;
    --info-color: #3b82f6;
    
    /* Shadows - keeping them standard for general depth */
    --shadow-sm: 0 1px 2px 0 rgba(0, 0, 0, 0.05);
    --shadow-md: 0 4px 6px -1px rgba(0, 0, 0, 0.1), 0 2px 4px -1px rgba(0, 0, 0, 0.06);
    --shadow-lg: 0 10px 15px -3px rgba(0, 0, 0, 0.1), 0 4px 6px -2px rgba(0, 0, 0, 0.05);
    --shadow-xl: 0 20px 25px -5px rgba(0, 0, 0, 0.1), 0 10px 10px -5px rgba(0, 0, 0, 0.04);
    --shadow-glow: 0 0 0 1px rgba(239, 68, 68, 0.1), 0 4px 16px rgba(239, 68, 68, 0.15); /* Red glow */
    
    /* Gradients */
    --gradient-primary: linear-gradient(135deg, #ef4444 0%, #dc2626 100%); /* Red gradient for accents */
    --gradient-secondary: linear-gradient(135deg, #f0f4f8 0%, #e2e8f0 100%); /* Subtle grey gradient for content areas */
    --gradient-success: linear-gradient(135deg, #4facfe 0%, #00f2fe 100%);
    --gradient-hero: linear-gradient(135deg, #ef4444 0%, #b91c1c 50%, #dc2626 100%); /* Red hero gradient for particles */
    --gradient-card: linear-gradient(145deg, rgba(255,255,255,0.9) 0%, rgba(255,255,255,0.7) 100%); /* Card background gradient */
    
    /* Border Radius */
    --radius-sm: 0.375rem;
    --radius-md: 0.5rem;
    --radius-lg: 0.75rem;
    --radius-xl: 1rem;
    --radius-2xl: 1.5rem;
    
    /* Transitions */
    --transition-fast: 0.15s ease-out;
    --transition-normal: 0.3s ease-out;
    --transition-slow: 0.5s ease-out;
}

[data-theme="dark"] {
    /* Dark Theme (Red and Black) */
    --bg-primary: #0f172a; /* Main background: Dark black */
    --bg-secondary: #1e293b; /* Slightly lighter black/dark grey for secondary background/content areas */
    --bg-tertiary: #334155; /* Even lighter black/dark grey */
    --bg-card: rgba(30, 41, 59, 0.95); /* Dark card background */
    --bg-accent: rgba(239, 68, 68, 0.2); /* Red accent background */
    --text-primary: #f1f5f9; /* Off-white text */
    --text-secondary: #cbd5e1;
    --text-muted: #64748b;
    --border-color: #334155; /* Darker border */
    --accent-primary: #ef4444; /* Red */
    --accent-secondary: #dc2626; /* Darker Red */
    --accent-hover: #b91c1c; /* Even Darker Red */
    --success-color: #34d399;
    --danger-color: #f87171;
    --warning-color: #fbbf24;
    --info-color: #60a5fa;
    
    --shadow-sm: 0 1px 2px 0 rgba(0, 0, 0, 0.3);
    --shadow-md: 0 4px 6px -1px rgba(0, 0, 0, 0.4), 0 2px 4px -1px rgba(0, 0, 0, 0.3);
    --shadow-lg: 0 10px 15px -3px rgba(0, 0, 0, 0.4), 0 4px 6px -2px rgba(0, 0, 0, 0.3);
    --shadow-xl: 0 20px 25px -5px rgba(0, 0, 0, 0.5), 0 10px 10px -5px rgba(0, 0, 0, 0.4);
    --shadow-glow: 0 0 0 1px rgba(239, 68, 68, 0.2), 0 4px 16px rgba(239, 68, 68, 0.3); /* Red glow */
    
    --gradient-card: linear-gradient(145deg, rgba(30, 41, 59, 0.95) 0%, rgba(51, 65, 85, 0.8) 100%);
}

/* Reset and Base Styles */
* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

html {
    scroll-behavior: smooth;
}

body {
    font-family: 'Inter', 'Segoe UI', system-ui, -apple-system, sans-serif;
    background: var(--bg-primary); /* Uses the primary background color */
    color: var(--text-primary);
    line-height: 1.6;
    transition: all var(--transition-normal);
    font-feature-settings: 'liga' 1, 'kern' 1;
    -webkit-font-smoothing: antialiased;
    -moz-osx-font-smoothing: grayscale;
}

/* Import Inter font */
@import url('https://fonts.googleapis.com/css2?family=Inter:wght@300;400;500;600;700;800&display=swap');

#globalcontainer {
    max-width: 1400px;
    margin: 0 auto;
    padding: 2rem;
    position: relative;
    z-index: 1;
}

/* Particles Background Enhancement */
#particles-js {
    position: fixed;
    width: 100%;
    height: 100%;
    top: 0;
    left: 0;
    z-index: -1;
    background: var(--bg-primary); 
    opacity: 0.9;
}

/* Enhanced Header Styles */
.SNORKY {
    background: linear-gradient(135deg, #FF4B2B 0%, #FF416C 100%); /* Fiery Red to Hot Pink/Orange (keeping this specific gradient for the SNORKY text) */
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
    font-size: clamp(2.5rem, 8vw, 4.5rem);
    font-weight: 800;
    text-align: center;
    margin-bottom: 1rem;
    letter-spacing: -0.02em;
    position: relative;
    animation: glow 3s ease-in-out infinite alternate;
}

@keyframes glow {
    from {
        filter: drop-shadow(0 0 20px rgba(239, 68, 68, 0.4)); /* Red glow */
    }
    to {
        filter: drop_shadow(0 0 30px rgba(239, 68, 68, 0.8)); /* Red glow */
    }
}

h1 {
    text-align: center;
    margin-bottom: 1.5rem;
}

p {
    text-align: center;
    color: var(--text-secondary); 
    font-size: 1.2rem;
    margin-bottom: 2.5rem;
    text-shadow: 0 2px 4px rgba(0, 0, 0, 0.3);
    font-weight: 400;
    max-width: 600px;
    margin-left: auto;
    margin-right: auto;
}

/* Modern Theme Toggle Button */
.theme-toggle-button {
    background: var(--gradient-primary);
    color: white;
    padding: 0.75rem 2rem;
    border: none;
    border-radius: var(--radius-xl);
    cursor: pointer;
    font-size: 1rem;
    font-weight: 600;
    transition: all var(--transition-normal);
    display: block;
    margin: 2rem auto;
    box-shadow: var(--shadow-lg);
    position: relative;
    overflow: hidden;
    backdrop-filter: blur(10px);
}

.theme-toggle-button::before {
    content: '';
    position: absolute;
    top: 0;
    left: -100%;
    width: 100%;
    height: 100%;
    background: linear-gradient(90deg, transparent, rgba(255,255,255,0.2), transparent);
    transition: left 0.5s;
}

.theme-toggle-button:hover::before {
    left: 100%;
}

.theme-toggle-button:hover {
    transform: translateY(-2px) scale(1.02);
    box-shadow: var(--shadow-xl);
}

.theme-toggle-button:active {
    transform: translateY(0) scale(0.98);
}

/* Modern Card/Container Styles */
.mainsquares {
    background: var(--gradient-card);
    border-radius: var(--radius-2xl);
    padding: 2rem;
    margin: 2rem 0;
    box-shadow: var(--shadow-lg);
    backdrop-filter: blur(20px);
    border: 1px solid var(--border-color);
    position: relative;
    overflow: hidden;
    transition: all var(--transition-normal);
}

.mainsquares::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    height: 1px;
    background: var(--gradient-primary);
    opacity: 0.5;
}

.mainsquares:hover {
    transform: translateY(-4px);
    box-shadow: var(--shadow-xl);
}

/* Form and Input Styling */
.rulebody {
    display: grid;
    gap: 2rem;
}

#headerInner1, #headerInner2 {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(140px, 1fr));
    gap: 1rem;
    align-items: center;
}

.headerelement, select {
    padding: 1rem;
    border: 2px solid var(--border-color);
    border-radius: var(--radius-lg);
    font-size: 0.95rem;
    font-weight: 500;
    background: var(--bg-card);
    color: var(--text-primary);
    transition: all var(--transition-normal);
    backdrop-filter: blur(10px);
    position: relative;
}

.headerelement::placeholder {
    color: var(--text-muted);
    font-weight: 400;
}

.headerelement:focus, select:focus {
    border-color: var(--accent-primary);
    outline: none;
    box-shadow: var(--shadow-glow);
    transform: translateY(-1px);
}

.headerelement:hover, select:hover {
    border-color: var(--accent-secondary);
    transform: translateY(-1px);
}

#rightarrow {
    font-size: 2.5rem;
    background: var(--gradient-primary);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
    font-weight: 800;
    text-align: center;
    display: flex;
    align-items: center;
    justify-content: center;
}

#rightarrow::after {
    content: '→';
}

/* Protocol Options Styling */
.protoOptions {
    display: grid;
    gap: 2rem;
}

.selectedProtoOptions {
    background: var(--bg-accent);
    border-radius: var(--radius-xl);
    padding: 2rem;
    border: 2px solid var(--accent-primary);
    position: relative;
    backdrop-filter: blur(10px);
}

.selectedProtoOptions::before {
    content: '';
    position: absolute;
    top: -1px;
    left: -1px;
    right: -1px;
    bottom: -1px;
    background: var(--gradient-primary);
    border-radius: var(--radius-xl);
    z-index: -1;
    opacity: 0.1;
}

.selectedProtoOptions h2 {
    background: var(--gradient-primary);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
    text-align: center;
    margin-bottom: 1.5rem;
    font-size: 1.75rem;
    font-weight: 700;
    letter-spacing: -0.01em;
}

.tcpinputs {
    margin: 0.5rem;
    padding: 0.75rem 1rem;
    border-radius: var(--radius-md);
    border: 2px solid var(--border-color);
    background: var(--bg-card);
    color: var(--text-primary);
    font-weight: 500;
    transition: all var(--transition-normal);
}

.tcpinputs:focus {
    border-color: var(--accent-primary);
    box-shadow: var(--shadow-glow);
    outline: none;
}

/* TCP Flags Styling */
.opflags {
    margin: 0 0.75rem 0.5rem 0;
    transform: scale(1.2);
    accent-color: var(--accent-primary);
}

.opflags + label {
    font-weight: 500;
    color: var(--text-primary);
    cursor: pointer;
    padding: 0.5rem;
    border-radius: var(--radius-sm);
    transition: all var(--transition-fast);
}

.opflags:checked + label {
    background: var(--bg-accent);
    color: var(--accent-primary);
}

/* Divider Styling */
.style1 {
    border: 0;
    height: 2px;
    background: var(--gradient-primary);
    margin: 2rem 0;
    border-radius: 1px;
    opacity: 0.6;
}

/* Misc Options */
#miscOptions {
    display: grid;
    gap: 1.5rem;
    margin-top: 2rem;
}

#miscOptions > div {
    display: flex;
    gap: 1rem;
    align-items: center;
    flex-wrap: wrap;
}

#miscOptions select, #miscOptions input {
    flex: 1;
    min-width: 120px;
    padding: 0.75rem;
    border: 2px solid var(--border-color);
    border-radius: var(--radius-md);
    background: var(--bg-card);
    color: var(--text-primary);
    font-weight: 500;
    transition: all var(--transition-normal);
}

/* Content Match Section */
.contentMatch {
    min-height: 400px;
}

.contentpluses {
    position: relative;
    display: flex;
    align-items: center;
    justify-content: space-between;
    padding: 1.5rem 2rem;
    background: var(--bg-secondary); 
    border-radius: var(--radius-xl);
    cursor: pointer;
    transition: all var(--transition-normal);
    margin: 1.5rem 0;
    overflow: hidden;
}

.contentpluses::before {
    content: '';
    position: absolute;
    top: 0;
    left: -100%;
    width: 100%;
    height: 100%;
    background: linear-gradient(90deg, transparent, rgba(255,255,255,0.1), transparent);
    transition: left 0.6s;
}

.contentpluses:hover::before {
    left: 100%;
}

.contentpluses:hover {
    transform: translateY(-3px) scale(1.02);
    box-shadow: var(--shadow-xl);
}

.contentHeaders {
    font-weight: 700;
    color: var(--text-primary); 
    font-size: 1.25rem;
    text-shadow: none; 
}

.plusexplode {
    transition: all var(--transition-normal);
    filter: drop-shadow(0 2px 4px rgba(0, 0, 0, 0.2));
}

.plusexplode:hover {
    transform: scale(1.1) rotate(90deg);
}

/* Content and PCRE Divs */
#contentdiv, #pcrediv {
    background: var(--bg-secondary);
    border-radius: var(--radius-xl);
    padding: 2rem;
    margin: 1.5rem 0;
    border: 2px solid var(--border-color); 
    backdrop-filter: blur(20px);
    box-shadow: var(--shadow-lg);
}

#contentdiv input, #pcrediv input {
    width: 100%;
    padding: 1rem;
    margin: 0.75rem 0;
    border: 2px solid var(--border-color);
    border-radius: var(--radius-lg);
    background: var(--bg-card);
    color: var(--text-primary);
    font-weight: 500;
    font-size: 1rem;
    transition: all var(--transition-normal);
}

#contentdiv input:focus, #pcrediv input:focus {
    border-color: var(--accent-primary);
    box-shadow: var(--shadow-glow);
    outline: none;
    transform: translateY(-1px);
}

.diditinput {
    width: calc(50% - 0.5rem) !important;
    display: inline-block;
}

.check {
    position: relative;
    margin: 0.75rem 1rem 0.75rem 0;
    display: inline-flex;
    align-items: center;
    gap: 0.5rem;
}

.check input[type="checkbox"] {
    width: auto !important;
    margin: 0 !important;
    transform: scale(1.2);
    accent-color: var(--accent-primary);
}

.check label {
    font-weight: 500;
    color: var(--text-primary);
    cursor: pointer;
    user-select: none;
}

/* Control Buttons */
.control-buttons {
    display: flex;
    gap: 1rem;
    justify-content: center;
    margin-top: 2rem;
}

.control-buttons img {
    cursor: pointer;
    transition: all var(--transition-normal);
    padding: 0.75rem;
    background: var(--bg-card);
    border-radius: var(--radius-lg);
    box-shadow: var(--shadow-md);
    backdrop-filter: blur(10px);
}

.control-buttons img:hover {
    transform: translateY(-2px) scale(1.1);
    box-shadow: var(--shadow-lg);
}

.control-buttons img:active {
    transform: translateY(0) scale(0.95);
}

/* Rule Output Styling */
.ruleOutput {
    background: var(--bg-secondary); 
    background-image: 
        linear-gradient(45deg, transparent 25%, rgba(0,0,0,0.02) 25%, rgba(0,0,0,0.02) 50%, transparent 50%, transparent 75%, rgba(0,0,0,0.02) 75%), /* Subtler pattern */
        var(--bg-primary); 
    color: var(--text-primary);
    font-family: 'JetBrains Mono', 'Fira Code', 'Consolas', monospace;
    min-height: 200px;
    position: relative;
    overflow: hidden;
    border-radius: var(--radius-2xl);
    border: 2px solid var(--accent-primary); /* Accent border to stand out slightly */
}

#innerRuleOutput {
    padding: 2rem;
    font-size: 0.95rem;
    line-height: 1.8;
    cursor: pointer;
    word-break: break-all;
    background: rgba(0, 0, 0, 0.05); /* Very subtle background for inner output */
    backdrop-filter: blur(10px);
    transition: all var(--transition-normal);
    position: relative;
    z-index: 1;
}

#innerRuleOutput:hover {
    background: rgba(0, 0, 0, 0.1);
    transform: scale(1.01);
}

#innerRuleOutput::before {
    content: 'Click to copy';
    position: absolute;
    top: 1rem;
    right: 1rem;
    background: var(--accent-primary);
    color: white;
    padding: 0.5rem 1rem;
    border-radius: var(--radius-md);
    font-size: 0.8rem;
    opacity: 0;
    transition: all var(--transition-normal);
    pointer-events: none;
}

#innerRuleOutput:hover::before {
    opacity: 1;
}

#GlobalResults {
    position: fixed;
    top: 2rem;
    right: 2rem;
    background: var(--gradient-card);
    color: white;
    padding: 1rem 2rem;
    border-radius: var(--radius-xl);
    font-weight: 700;
    z-index: 1000;
    box-shadow: var(--shadow-xl);
    backdrop-filter: blur(10px);
    animation: slideInRight 0.3s ease-out;
}

@keyframes slideInRight {
    from {
        transform: translateX(100%);
        opacity: 0;
    }
    to {
        transform: translateX(0);
        opacity: 1;
    }
}

/* Footer Links */
.footer-link {
    text-align: center;
    margin-top: 3rem;
    padding: 2rem;
    background: rgba(255, 255, 255, 0.1);
    border-radius: var(--radius-xl);
    backdrop-filter: blur(10px);
}

.footer-link span {
    color: rgba(255, 255, 255, 0.8);
    font-weight: 500;
    margin: 0 1rem;
}

.footer-link a {
    color: var(--accent-secondary);
    text-decoration: none;
    margin: 0 1rem;
    font-weight: 600;
    padding: 0.5rem 1rem;
    border-radius: var(--radius-md);
    transition: all var(--transition-normal);
    background: rgba(255, 255, 255, 0.1);
    backdrop-filter: blur(10px);
}

.footer-link a:hover {
    background: var(--accent-secondary);
    color: white;
    transform: translateY(-2px);
    box-shadow: var(--shadow-lg);
}

/* Error Animation */
.error-shake {
    animation: shake 0.6s ease-in-out;
    border-color: var(--danger-color) !important; /* Highlight border on error */
    box-shadow: 0 0 0 3px rgba(239, 68, 68, 0.5) !important; /* Red glow on error */
}

@keyframes shake {
    0%, 100% { transform: translateX(0); }
    10%, 30%, 50%, 70%, 90% { transform: translateX(-4px); }
    20%, 40%, 60%, 80% { transform: translateX(4px); }
}

/* Loading States */
.loading {
    opacity: 0.6;
    pointer-events: none;
    position: relative;
}

.loading::after {
    content: '';
    position: absolute;
    top: 50%;
    left: 50%;
    width: 2rem;
    height: 2rem;
    margin: -1rem 0 0 -1rem;
    border: 2px solid var(--accent-primary);
    border-radius: 50%;
    border-top-color: transparent;
    animation: spin 1s linear infinite;
}

@keyframes spin {
    to { transform: rotate(360deg); }
}

/* Responsive Design */
@media (max-width: 1200px) {
    #globalcontainer {
        max-width: 100%;
        padding: 1.5rem;
    }
}

@media (max-width: 768px) {
    .SNORKY {
        font-size: clamp(2rem, 10vw, 3rem);
    }
    
    #headerInner1, #headerInner2 {
        grid-template-columns: 1fr;
        gap: 1rem;
    }
    
    .mainsquares {
        padding: 1.5rem;
        margin: 1.5rem 0;
    }
    
    .contentpluses {
        padding: 1rem 1.5rem;
    }
    
    #contentdiv, #pcrediv {
        padding: 1.5rem;
    }
    
    .diditinput {
        width: 100% !important;
        margin-bottom: 0.5rem;
    }
    
    #miscOptions > div {
        flex-direction: column;
        align-items: stretch;
    }
    
    #miscOptions select, #miscOptions input {
        width: 100%;
    }
    
    .control-buttons {
        gap: 0.75rem;
    }
    
    #GlobalResults {
        top: 1rem;
        right: 1rem;
        left: 1rem;
        text-align: center;
    }
}

@media (max-width: 480px) {
    #globalcontainer {
        padding: 1rem;
    }
    
    .mainsquares {
        padding: 1rem;
    }
    
    p {
        font-size: 1rem;
    }
    
    .theme-toggle-button {
        padding: 0.5rem 1.5rem;
        font-size: 0.9rem;
    }
}

/* High contrast mode support */
@media (prefers-contrast: high) {
    :root {
        --shadow-sm: 0 1px 2px 0 rgba(0, 0, 0, 0.8);
        --shadow-md: 0 4px 6px -1px rgba(0, 0, 0, 0.8);
        --shadow-lg: 0 10px 15px -3px rgba(0, 0, 0, 0.8);
        --shadow-xl: 0 20px 25px -5px rgba(0, 0, 0, 0.8);
    }
    
    .mainsquares {
        border: 3px solid var(--accent-primary);
    }
}

/* Reduced motion support */
@media (prefers-reduced-motion: reduce) {
    *,
    *::before,
    *::after {
        animation-duration: 0.01ms !important;
        animation-iteration-count: 1 !important;
        transition-duration: 0.01ms !important;
    }
}