/* Core Reset and Variables */
:root {
    --bg-main: #0b0f19;
    --bg-darker: #05070c;
    --bg-card: rgba(17, 24, 39, 0.7);
    --bg-input: rgba(3, 7, 18, 0.6);
    
    --border-glass: rgba(255, 255, 255, 0.08);
    --border-active: rgba(139, 92, 246, 0.6);
    
    --text-primary: #f3f4f6;
    --text-secondary: #9ca3af;
    --text-muted: #6b7280;
    
    --accent-indigo: #6366f1;
    --accent-purple: #8b5cf6;
    --accent-pink: #ec4899;
    --accent-success: #10b981;
    --accent-danger: #ef4444;
    --accent-info: #06b6d4;
    --accent-warning: #f59e0b;
    
    --accent-grad: linear-gradient(135deg, #6366f1, #8b5cf6, #d946ef);
    --btn-shadow: 0 4px 14px 0 rgba(139, 92, 246, 0.4);
    
    --font-outfit: 'Outfit', sans-serif;
    --font-grotesk: 'Space Grotesk', sans-serif;
    
    --transition-smooth: all 0.3s cubic-bezier(0.4, 0, 0.2, 1);
}

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

body {
    background-color: var(--bg-main);
    color: var(--text-primary);
    font-family: var(--font-outfit);
    line-height: 1.6;
    overflow-x: hidden;
    min-height: 100vh;
}

/* Beautiful Decorative Glows */
.decor-glow {
    position: absolute;
    border-radius: 50%;
    filter: blur(100px);
    opacity: 0.15;
    pointer-events: none;
    z-index: 0;
}
.glow-1 {
    width: 40vw;
    height: 40vw;
    background: var(--accent-indigo);
    top: -10vw;
    left: -10vw;
    animation: pulse-glow 15s infinite alternate;
}
.glow-2 {
    width: 35vw;
    height: 35vw;
    background: var(--accent-pink);
    bottom: -5vw;
    right: -5vw;
    animation: pulse-glow 12s infinite alternate-reverse;
}
.glow-3 {
    width: 25vw;
    height: 25vw;
    background: var(--accent-purple);
    top: 30vh;
    left: 45vw;
}

@keyframes pulse-glow {
    0% { transform: scale(1) translate(0, 0); opacity: 0.1; }
    100% { transform: scale(1.15) translate(40px, 30px); opacity: 0.2; }
}

/* Scrollbar Customization */
::-webkit-scrollbar {
    width: 8px;
    height: 8px;
}
::-webkit-scrollbar-track {
    background: var(--bg-darker);
}
::-webkit-scrollbar-thumb {
    background: rgba(255, 255, 255, 0.15);
    border-radius: 4px;
}
::-webkit-scrollbar-thumb:hover {
    background: var(--accent-purple);
}

/* Bố cục chính Dashboard */
.app-container {
    position: relative;
    z-index: 1;
    display: grid;
    grid-template-columns: 280px 1fr;
    min-height: 100vh;
}

/* Sidebar Styling */
.app-sidebar {
    background-color: rgba(5, 7, 12, 0.85);
    border-right: 1px solid var(--border-glass);
    backdrop-filter: blur(20px);
    padding: 2rem 1.5rem;
    display: flex;
    flex-direction: column;
    height: 100vh;
    position: sticky;
    top: 0;
}

/* Sidebar Hamburger Menu Toggle (Hidden on desktop) */
.menu-toggle {
    display: none;
}

.brand-logo {
    display: flex;
    align-items: center;
    gap: 0.85rem;
    margin-bottom: 2.5rem;
    padding-left: 0.25rem;
}

.logo-icon {
    font-size: 2rem;
    filter: drop-shadow(0 0 10px var(--accent-purple));
}

.brand-name {
    display: flex;
    flex-direction: column;
    font-family: var(--font-grotesk);
}

.brand-name span:first-child {
    font-size: 1.15rem;
    font-weight: 800;
    letter-spacing: 1px;
    background: var(--accent-grad);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
}

.badge-premium {
    font-size: 0.65rem;
    font-weight: 700;
    color: var(--accent-indigo);
    letter-spacing: 1.5px;
    margin-top: 0.1rem;
}

.sidebar-nav {
    display: flex;
    flex-direction: column;
    gap: 0.5rem;
}

.nav-tab-btn {
    background: transparent;
    border: 1px solid transparent;
    color: var(--text-secondary);
    font-family: var(--font-outfit);
    font-size: 0.95rem;
    font-weight: 500;
    text-align: left;
    padding: 0.85rem 1rem;
    border-radius: 12px;
    cursor: pointer;
    display: flex;
    align-items: center;
    gap: 0.75rem;
    transition: var(--transition-smooth);
}

.nav-tab-btn:hover {
    color: var(--text-primary);
    background-color: rgba(255, 255, 255, 0.04);
}

.nav-tab-btn.active {
    color: var(--text-primary);
    background: rgba(139, 92, 246, 0.12);
    border-color: rgba(139, 92, 246, 0.25);
    box-shadow: inset 0 0 12px rgba(139, 92, 246, 0.05);
}

.nav-tab-btn.active .nav-icon {
    transform: scale(1.15);
    filter: drop-shadow(0 0 6px var(--accent-purple));
}

.nav-icon {
    font-size: 1.15rem;
    transition: var(--transition-smooth);
}

.sidebar-footer {
    margin-top: auto;
    padding-top: 1.5rem;
    border-top: 1px solid var(--border-glass);
}

.author-credits {
    font-size: 0.75rem;
    color: var(--text-muted);
    text-align: center;
    font-weight: 500;
}

/* Main Workspace Area */
.app-main {
    padding: 2.5rem 3rem;
    overflow-y: auto;
}

.app-header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    margin-bottom: 2.5rem;
    border-bottom: 1px solid var(--border-glass);
    padding-bottom: 1.5rem;
}

.app-header h1 {
    font-family: var(--font-grotesk);
    font-size: 1.85rem;
    font-weight: 700;
    letter-spacing: -0.5px;
    color: var(--text-primary);
}

.app-header .subtitle {
    font-size: 0.95rem;
    color: var(--text-secondary);
}

.time-badge {
    background: rgba(255, 255, 255, 0.03);
    border: 1px solid var(--border-glass);
    color: var(--accent-purple);
    font-family: var(--font-grotesk);
    font-size: 0.95rem;
    font-weight: 600;
    padding: 0.45rem 1rem;
    border-radius: 30px;
    box-shadow: 0 0 15px rgba(139, 92, 246, 0.05);
}

/* Tab contents rendering */
.tab-content {
    display: none;
    animation: fadeTab 0.4s cubic-bezier(0.16, 1, 0.3, 1) forwards;
}

.tab-content.active {
    display: block;
}

@keyframes fadeTab {
    from {
        opacity: 0;
        transform: translateY(12px);
    }
    to {
        opacity: 1;
        transform: translateY(0);
    }
}

/* Layout Grids */
.grid-layout {
    display: grid;
    grid-template-columns: 1fr;
    gap: 2.5rem;
}

.grid-layout.single-col {
    grid-template-columns: 1fr;
}

/* Glassmorphic Cards */
.glass-card {
    background: var(--bg-card);
    border: 1px solid var(--border-glass);
    backdrop-filter: blur(16px);
    border-radius: 20px;
    padding: 2rem;
    box-shadow: 0 10px 30px -10px rgba(0, 0, 0, 0.5);
    transition: var(--transition-smooth);
}

.glass-card:hover {
    border-color: rgba(255, 255, 255, 0.12);
    box-shadow: 0 15px 40px -10px rgba(0, 0, 0, 0.6);
}

.card-header {
    margin-bottom: 1.75rem;
}

.card-title {
    font-family: var(--font-grotesk);
    font-size: 1.35rem;
    font-weight: 700;
    color: var(--text-primary);
    display: flex;
    align-items: center;
    gap: 0.85rem;
}

.card-title span {
    display: flex;
    align-items: center;
    justify-content: center;
    width: 28px;
    height: 28px;
    border-radius: 8px;
    background: var(--accent-grad);
    font-size: 0.95rem;
    color: var(--text-primary);
}

.card-subtitle {
    font-size: 0.9rem;
    color: var(--text-secondary);
    margin-top: 0.25rem;
}

/* Form Controls & Inputs */
.controls-row {
    display: flex;
    justify-content: space-between;
    align-items: flex-end;
    gap: 1.5rem;
    margin-bottom: 1.5rem;
    flex-wrap: wrap;
}

.controls-row.flex-end {
    justify-content: flex-end;
}

.controls-row.flex-between {
    justify-content: space-between;
}

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

.input-label {
    font-size: 0.85rem;
    font-weight: 600;
    letter-spacing: 0.5px;
    text-transform: uppercase;
    color: var(--text-secondary);
}

.input-with-addon {
    display: flex;
    align-items: center;
    background: var(--bg-input);
    border: 1px solid var(--border-glass);
    border-radius: 10px;
    overflow: hidden;
    transition: var(--transition-smooth);
}

.input-with-addon:focus-within {
    border-color: var(--border-active);
    box-shadow: 0 0 10px rgba(139, 92, 246, 0.15);
}

.form-input {
    background: transparent;
    border: none;
    color: var(--text-primary);
    font-family: var(--font-outfit);
    font-size: 0.95rem;
    font-weight: 600;
    padding: 0.65rem 1rem;
    outline: none;
}

.form-input.text-center {
    text-align: center;
}

input[type=number]::-webkit-inner-spin-button, 
input[type=number]::-webkit-outer-spin-button {
    -webkit-appearance: none;
    margin: 0;
}

.addon-text {
    background: rgba(255, 255, 255, 0.03);
    border-left: 1px solid var(--border-glass);
    color: var(--text-secondary);
    font-size: 0.85rem;
    font-weight: 600;
    padding: 0 0.85rem;
    height: 100%;
    display: flex;
    align-items: center;
}

.custom-select {
    background-color: var(--bg-input);
    border: 1px solid var(--border-glass);
    border-radius: 10px;
    padding: 0.65rem 1.5rem 0.65rem 1rem;
    font-family: var(--font-outfit);
    font-weight: 600;
    color: var(--text-primary);
    outline: none;
    cursor: pointer;
    transition: var(--transition-smooth);
}

.custom-select:focus {
    border-color: var(--border-active);
    box-shadow: 0 0 10px rgba(139, 92, 246, 0.15);
}

/* Beautiful Premium Buttons */
.button-group {
    display: flex;
    gap: 0.5rem;
}

.flex-wrap {
    flex-wrap: wrap;
}

.justify-end {
    justify-content: flex-end;
}

.justify-center {
    justify-content: center;
}

.align-center {
    align-items: center;
}

.btn {
    border: 1px solid transparent;
    border-radius: 10px;
    font-family: var(--font-outfit);
    font-size: 0.85rem;
    font-weight: 600;
    padding: 0.65rem 1.15rem;
    cursor: pointer;
    transition: var(--transition-smooth);
    display: inline-flex;
    align-items: center;
    justify-content: center;
}

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

.btn-primary:hover {
    background: #7c3aed;
    transform: translateY(-1px);
}

.btn-primary:active {
    transform: translateY(0);
}

.btn-glow {
    background: var(--accent-grad);
    box-shadow: var(--btn-shadow);
}

.btn-glow:hover {
    box-shadow: 0 6px 20px 0 rgba(139, 92, 246, 0.6);
    transform: translateY(-2px);
}

.btn-secondary {
    background: rgba(255, 255, 255, 0.05);
    border-color: var(--border-glass);
    color: var(--text-primary);
}

.btn-secondary:hover {
    background: rgba(255, 255, 255, 0.08);
}

.btn-accent {
    background: rgba(6, 182, 212, 0.15);
    border-color: rgba(6, 182, 212, 0.25);
    color: var(--accent-info);
}

.btn-accent:hover {
    background: rgba(6, 182, 212, 0.25);
    transform: translateY(-1px);
}

.btn-danger {
    background: rgba(239, 68, 68, 0.12);
    border-color: rgba(239, 68, 68, 0.2);
    color: var(--accent-danger);
}

.btn-danger:hover {
    background: rgba(239, 68, 68, 0.22);
    transform: translateY(-1px);
}

.btn-info {
    background: rgba(99, 102, 241, 0.15);
    border-color: rgba(99, 102, 241, 0.2);
    color: var(--accent-indigo);
}

.btn-info:hover {
    background: rgba(99, 102, 241, 0.25);
    transform: translateY(-1px);
}

/* Modern Textareas Grid */
.textareas-grid {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 1.5rem;
}

.textarea-container {
    display: flex;
    flex-direction: column;
    gap: 0.5rem;
    position: relative;
}

.area-label {
    font-size: 0.8rem;
    font-weight: 600;
    text-transform: uppercase;
    letter-spacing: 0.5px;
    color: var(--text-secondary);
    padding-left: 0.25rem;
}

.modern-textarea {
    background: var(--bg-input);
    border: 1px solid var(--border-glass);
    border-radius: 12px;
    color: var(--text-primary);
    font-family: monospace;
    font-size: 0.95rem;
    line-height: 1.5;
    padding: 1rem;
    width: 100%;
    min-height: 200px;
    resize: vertical;
    outline: none;
    transition: var(--transition-smooth);
}

.modern-textarea:focus {
    border-color: var(--border-active);
    box-shadow: 0 0 12px rgba(139, 92, 246, 0.1);
}

.modern-textarea.output-area {
    background: rgba(5, 7, 12, 0.4);
    font-weight: 500;
    color: var(--text-primary);
}

.modern-textarea.small-height {
    min-height: 80px;
    height: 80px;
}

.modern-textarea.medium-height {
    min-height: 180px;
}

.modern-textarea.large-height {
    min-height: 310px;
}

/* Interactive Textarea Footer */
.textarea-footer {
    display: flex;
    justify-content: flex-end;
    align-items: center;
    gap: 0.85rem;
    position: absolute;
    bottom: 10px;
    right: 10px;
    z-index: 10;
}

.count-badge {
    background: rgba(16, 185, 129, 0.1);
    border: 1px solid rgba(16, 185, 129, 0.25);
    color: var(--accent-success);
    font-family: var(--font-grotesk);
    font-size: 0.75rem;
    font-weight: 600;
    padding: 0.2rem 0.65rem;
    border-radius: 6px;
    text-shadow: 0 0 4px rgba(16, 185, 129, 0.2);
}

.btn-copy {
    background: rgba(255, 255, 255, 0.05);
    border: 1px solid var(--border-glass);
    color: var(--text-secondary);
    font-family: var(--font-outfit);
    font-size: 0.75rem;
    font-weight: 600;
    padding: 0.3rem 0.85rem;
    border-radius: 6px;
    cursor: pointer;
    transition: var(--transition-smooth);
}

.btn-copy:hover {
    background: var(--accent-purple);
    border-color: var(--accent-purple);
    color: var(--text-primary);
    box-shadow: 0 0 10px rgba(139, 92, 246, 0.3);
}

.btn-copy.copied {
    background: var(--accent-success);
    border-color: var(--accent-success);
    color: var(--text-primary);
    box-shadow: 0 0 10px rgba(16, 185, 129, 0.3);
}

/* Layout 3D-4D Split Inputs */
.multi-inputs-layout {
    display: grid;
    grid-template-columns: 1fr 1.5fr;
    gap: 1.5rem;
}

.inputs-stack {
    display: flex;
    flex-direction: column;
}

.textarea-container.output-container {
    height: 100%;
}

.textarea-container.output-container .modern-textarea {
    flex-grow: 1;
}

/* Filter inputs cards in TAB 3 */
.filter-inputs-grid {
    display: grid;
    grid-template-columns: repeat(5, 1fr);
    gap: 1rem;
    margin-bottom: 1.25rem;
}

.filter-input-col {
    display: flex;
    flex-direction: column;
    gap: 0.4rem;
}

.filter-input-col.span-2 {
    grid-column: span 2;
}

.filter-input-col.full-width {
    grid-column: span 5;
}

.filter-label {
    font-size: 0.75rem;
    font-weight: 700;
    text-transform: uppercase;
    color: var(--text-secondary);
}

.text-success {
    color: var(--accent-success) !important;
}

.text-danger {
    color: var(--accent-danger) !important;
}

.filter-textarea {
    background: var(--bg-input);
    border: 1px solid var(--border-glass);
    border-radius: 8px;
    color: var(--text-primary);
    font-family: monospace;
    font-size: 0.95rem;
    padding: 0.5rem;
    height: 60px;
    resize: none;
    outline: none;
    transition: var(--transition-smooth);
}

.filter-textarea:focus {
    border-color: var(--border-active);
}

.success-border {
    border-color: rgba(16, 185, 129, 0.2);
}
.success-border:focus {
    border-color: var(--accent-success);
}

.danger-border {
    border-color: rgba(239, 68, 68, 0.2);
}
.danger-border:focus {
    border-color: var(--accent-danger);
}

/* Selector Dashboard in TAB 4 */
.quick-selectors-dashboard {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 1.5rem;
}

.selector-group-card {
    background: rgba(255, 255, 255, 0.02);
    border: 1px solid var(--border-glass);
    border-radius: 12px;
    padding: 1.15rem;
}

.selector-group-card.span-2 {
    grid-column: span 2;
}

.group-title {
    font-family: var(--font-grotesk);
    font-size: 0.85rem;
    font-weight: 700;
    text-transform: uppercase;
    letter-spacing: 0.5px;
    margin-bottom: 0.85rem;
    padding-bottom: 0.4rem;
    border-bottom: 1px solid var(--border-glass);
}

.group-title.label-dau { color: #f97316; }
.group-title.label-duoi { color: #c084fc; }
.group-title.label-tong { color: #f43f5e; }
.group-title.label-chanle { color: #34d399; }
.group-title.label-taixiu { color: #f472b6; }
.group-title.label-kep { color: #fbbf24; }
.group-title.label-hieu { color: #a78bfa; }
.group-title.label-congiap { color: #cbd5e1; }
.group-title.label-hinhhoc { color: #fda4af; }
.group-title.label-chiadu { color: #22d3ee; }

.buttons-grid {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 0.4rem;
}

.buttons-grid.grid-10 {
    grid-template-columns: repeat(5, 1fr);
}

.buttons-grid.grid-12 {
    grid-template-columns: repeat(6, 1fr);
}

.span-5 {
    grid-column: span 3;
}

.bg-black {
    background-color: #000 !important;
}

.text-white {
    color: #fff !important;
}

.btn-quick {
    border: 1px solid transparent;
    border-radius: 6px;
    font-family: var(--font-outfit);
    font-size: 0.75rem;
    font-weight: 600;
    padding: 0.45rem;
    cursor: pointer;
    text-align: center;
    color: var(--text-primary);
    transition: var(--transition-smooth);
    background-color: rgba(255, 255, 255, 0.03);
}

.btn-quick:active {
    transform: scale(0.97);
}

.btn-quick.label-dau {
    border-color: rgba(249, 115, 22, 0.15);
}
.btn-quick.label-dau:hover,
.btn-quick.label-dau.active {
    background-color: #f97316;
    box-shadow: 0 0 10px rgba(249, 115, 22, 0.4);
    border-color: #f97316;
}

.btn-quick.label-duoi {
    border-color: rgba(192, 132, 252, 0.15);
}
.btn-quick.label-duoi:hover,
.btn-quick.label-duoi.active {
    background-color: #a855f7;
    box-shadow: 0 0 10px rgba(168, 85, 247, 0.4);
    border-color: #a855f7;
}

.btn-quick.label-tong {
    border-color: rgba(244, 63, 94, 0.15);
}
.btn-quick.label-tong:hover,
.btn-quick.label-tong.active {
    background-color: #e11d48;
    box-shadow: 0 0 10px rgba(225, 29, 72, 0.4);
    border-color: #e11d48;
}

.btn-quick.label-chanle {
    border-color: rgba(52, 211, 153, 0.15);
}
.btn-quick.label-chanle:hover,
.btn-quick.label-chanle.active {
    background-color: #10b981;
    box-shadow: 0 0 10px rgba(16, 185, 129, 0.4);
    border-color: #10b981;
}

.btn-quick.label-taixiu {
    border-color: rgba(244, 114, 182, 0.15);
}
.btn-quick.label-taixiu:hover,
.btn-quick.label-taixiu.active {
    background-color: #ec4899;
    box-shadow: 0 0 10px rgba(236, 72, 153, 0.4);
    border-color: #ec4899;
}

.btn-quick.label-kep {
    border-color: rgba(251, 191, 36, 0.15);
}
.btn-quick.label-kep:hover,
.btn-quick.label-kep.active {
    background-color: #d97706;
    box-shadow: 0 0 10px rgba(217, 119, 6, 0.4);
    border-color: #d97706;
}

.btn-quick.label-hieu {
    border-color: rgba(167, 139, 250, 0.15);
}
.btn-quick.label-hieu:hover,
.btn-quick.label-hieu.active {
    background-color: #7c3aed;
    box-shadow: 0 0 10px rgba(124, 58, 237, 0.4);
    border-color: #7c3aed;
}

.btn-quick.label-congiap {
    border-color: rgba(203, 213, 225, 0.15);
}
.btn-quick.label-congiap:hover,
.btn-quick.label-congiap.active {
    background-color: #64748b;
    box-shadow: 0 0 10px rgba(100, 116, 139, 0.4);
    border-color: #64748b;
}

.btn-quick.label-hinhhoc {
    border-color: rgba(253, 164, 175, 0.15);
}
.btn-quick.label-hinhhoc:hover,
.btn-quick.label-hinhhoc.active {
    background-color: #f43f5e;
    box-shadow: 0 0 10px rgba(244, 63, 94, 0.4);
    border-color: #f43f5e;
}

.btn-quick.label-chiadu {
    border-color: rgba(34, 211, 238, 0.15);
}
.btn-quick.label-chiadu:hover,
.btn-quick.label-chiadu.active {
    background-color: #06b6d4;
    box-shadow: 0 0 10px rgba(6, 182, 212, 0.4);
    border-color: #06b6d4;
}

/* Glassmorphic Small Result Box for Selectors */
.group-result-box {
    background: rgba(255, 255, 255, 0.025);
    border: 1px solid var(--border-glass);
    border-radius: 10px;
    padding: 0.65rem 0.85rem;
    margin-top: 0.75rem;
    display: flex;
    flex-direction: column;
    gap: 0.4rem;
    box-shadow: inset 0 0 15px rgba(255, 255, 255, 0.01);
    animation: fadeInResult 0.3s cubic-bezier(0.16, 1, 0.3, 1) forwards;
}

@keyframes fadeInResult {
    from {
        opacity: 0;
        transform: translateY(4px);
    }
    to {
        opacity: 1;
        transform: translateY(0);
    }
}

.result-header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    border-bottom: 1px solid rgba(255, 255, 255, 0.04);
    padding-bottom: 0.35rem;
}

.selected-label {
    font-family: var(--font-grotesk);
    font-size: 0.75rem;
    font-weight: 700;
    text-transform: uppercase;
    letter-spacing: 0.5px;
    color: var(--text-primary);
    display: inline-flex;
    align-items: center;
}

.result-content-wrapper {
    display: flex;
    gap: 0.5rem;
    align-items: stretch;
}

.result-textarea-small {
    background: rgba(3, 7, 18, 0.55);
    border: 1px solid var(--border-glass);
    border-radius: 8px;
    color: var(--text-primary);
    font-family: monospace;
    font-size: 0.85rem;
    line-height: 1.4;
    padding: 0.45rem 0.65rem;
    width: 100%;
    min-height: 48px;
    resize: none;
    outline: none;
    overflow-y: hidden;
    transition: border-color 0.3s, background-color 0.3s;
}

.result-textarea-small:focus {
    border-color: var(--border-active);
    background: rgba(3, 7, 18, 0.7);
}

.btn-copy-small {
    background: rgba(255, 255, 255, 0.04);
    border: 1px solid var(--border-glass);
    color: var(--text-secondary);
    font-family: var(--font-outfit);
    font-size: 0.7rem;
    font-weight: 700;
    padding: 0 0.85rem;
    border-radius: 6px;
    cursor: pointer;
    transition: var(--transition-smooth);
    display: inline-flex;
    align-items: center;
    justify-content: center;
    min-width: 60px;
    user-select: none;
}

.btn-copy-small:hover {
    background: var(--accent-purple);
    border-color: var(--accent-purple);
    color: var(--text-primary);
    box-shadow: 0 0 10px rgba(139, 92, 246, 0.35);
}

.btn-copy-small.copied {
    background: var(--accent-success);
    border-color: var(--accent-success);
    color: var(--text-primary);
    box-shadow: 0 0 10px rgba(16, 185, 129, 0.35);
}

/* Compare TAB 5 inputs */
.textareas-triple-grid {
    display: grid;
    grid-template-columns: 1fr 1fr 1fr;
    gap: 1.5rem;
}

/* SEO Footer informative card */
.app-footer {
    margin-top: 3rem;
    border-top: 1px solid var(--border-glass);
    padding-top: 2rem;
}

.footer-intro-card {
    background: rgba(255, 255, 255, 0.015);
    border: 1px solid var(--border-glass);
    border-radius: 16px;
    padding: 1.5rem 2rem;
}

.footer-intro-card h3 {
    font-family: var(--font-grotesk);
    font-size: 1.1rem;
    font-weight: 700;
    margin-bottom: 0.75rem;
    color: var(--text-primary);
}

.footer-intro-card p {
    font-size: 0.85rem;
    color: var(--text-secondary);
    margin-bottom: 0.75rem;
}
.footer-intro-card p:last-child {
    margin-bottom: 0;
}

/* Touch Optimizations & General Performance Settings */
button, 
input, 
select, 
textarea {
    -webkit-tap-highlight-color: transparent;
    touch-action: manipulation;
}

/* Premium Responsive Styles & Layout Refinement */
@media screen and (max-width: 1024px) {
    .app-container {
        grid-template-columns: 1fr;
        padding-top: 0; /* Changed from 70px to 0 since sidebar is now relative within the page flow */
    }
    
    .app-sidebar {
        position: relative; /* Changed from fixed to relative to sit inside the page container */
        height: auto;
        flex-direction: column;
        align-items: stretch;
        justify-content: flex-start;
        padding: 1.5rem 1.5rem 1.25rem 1.5rem;
        z-index: 100;
        border-right: none;
        border-bottom: 1px solid var(--border-glass);
        background: rgba(5, 7, 12, 0.85);
        backdrop-filter: blur(20px);
        -webkit-backdrop-filter: blur(20px);
        box-shadow: 0 4px 20px rgba(0, 0, 0, 0.2);
    }
    
    .brand-logo {
        margin-bottom: 1.25rem;
        justify-content: center;
        padding-left: 0;
    }
    
    /* Premium Hamburger Toggle Button */
    .menu-toggle {
        display: none !important;
    }
    
    /* Dropdown Drawer Menu */
    .sidebar-nav {
        position: relative;
        top: auto;
        left: auto;
        right: auto;
        background: transparent;
        backdrop-filter: none;
        -webkit-backdrop-filter: none;
        border: none;
        padding: 0;
        flex-direction: row;
        flex-wrap: wrap;
        gap: 0.5rem;
        max-width: 100%;
        width: 100%;
        overflow-x: visible;
        overflow-y: visible;
        max-height: none;
        transform: none;
        opacity: 1;
        visibility: visible;
        box-shadow: none;
        z-index: 1;
    }
    
    .sidebar-nav.active {
        transform: none;
        opacity: 1;
        visibility: visible;
    }
    
    .nav-tab-btn {
        flex: 1 1 calc(33.333% - 0.35rem);
        justify-content: center;
        padding: 0.75rem 1rem;
        font-size: 0.9rem;
        white-space: nowrap;
        background: rgba(255, 255, 255, 0.02);
        border: 1px solid rgba(255, 255, 255, 0.05);
        border-radius: 12px;
        color: var(--text-secondary);
        display: flex;
        align-items: center;
        gap: 0.5rem;
        transition: var(--transition-smooth);
    }
    
    .nav-tab-btn:hover {
        background: rgba(255, 255, 255, 0.06);
        color: var(--text-primary);
        border-color: rgba(255, 255, 255, 0.15);
    }
    
    .nav-tab-btn.active {
        background: var(--accent-grad);
        color: var(--text-primary);
        border-color: transparent;
        box-shadow: var(--shadow-glow);
    }
    
    .sidebar-footer {
        display: none;
    }
    
    .app-main {
        padding: 2rem 1.5rem;
    }
    
    .textareas-triple-grid {
        grid-template-columns: 1fr 1fr;
    }
    
    .span-md-full {
        grid-column: span 2;
    }
}

@media screen and (max-width: 900px) {
    .textareas-grid,
    .multi-inputs-layout,
    .quick-selectors-dashboard {
        grid-template-columns: 1fr;
    }
    
    .textarea-container.output-container {
        height: auto;
    }
    
    .filter-inputs-grid {
        grid-template-columns: repeat(2, 1fr);
    }
    
    .filter-input-col.span-2,
    .filter-input-col.full-width {
        grid-column: span 2;
    }
    
    .selector-group-card.span-2 {
        grid-column: span 1;
    }
    
    .buttons-grid.grid-10,
    .buttons-grid.grid-12 {
        grid-template-columns: repeat(4, 1fr);
    }
    
    .span-5 {
        grid-column: span 2;
    }
}

@media screen and (max-width: 640px) {
    .app-sidebar {
        height: auto;
        padding: 1.25rem 1rem 0.75rem 1rem;
    }
    
    .brand-logo {
        margin-bottom: 1rem;
    }
    
    .brand-name {
        display: flex !important; /* Keep brand name text visible as we stack elements vertically */
    }
    
    .logo-icon {
        font-size: 1.75rem;
    }
    
    .sidebar-nav {
        top: auto;
        padding: 0;
        gap: 0.4rem;
        max-width: 100%;
    }
    
    .nav-tab-btn {
        flex: 1 1 calc(50% - 0.2rem); /* 2 columns grid on mobile */
        padding: 0.65rem 0.85rem;
        font-size: 0.85rem;
        border-radius: 8px;
        gap: 0.4rem;
    }
    
    .app-main {
        padding: 1.25rem 0.85rem;
    }
    
    .app-header {
        flex-direction: column;
        align-items: flex-start;
        gap: 0.75rem;
    }
    
    .filter-inputs-grid {
        grid-template-columns: 1fr;
    }
    
    .filter-input-col.span-2,
    .filter-input-col.full-width {
        grid-column: span 1;
    }
    
    .buttons-grid.grid-10,
    .buttons-grid.grid-12 {
        grid-template-columns: repeat(3, 1fr);
    }
    
    .span-5 {
        grid-column: span 1;
    }
    
    .textareas-triple-grid {
        grid-template-columns: 1fr;
    }
    
    .span-md-full {
        grid-column: span 1;
    }
    
    .controls-row {
        flex-direction: column;
        align-items: stretch;
    }
    
    .button-group {
        justify-content: flex-start;
    }
}