/* ============================================
   MODERN MATRIX CALCULATOR - PRODUCTION CSS
   Glassmorphism + Light/Dark Theme + Responsive
   ============================================ */

:root {
    /* Light Theme (Default) */
    --bg-gradient-start: #f5f7fe;
    --bg-gradient-end: #e9eef5;
    --card-bg: rgba(255, 255, 255, 0.75);
    --card-border: rgba(255, 255, 255, 0.5);
    --card-shadow: 0 8px 32px rgba(31, 38, 135, 0.1);
    --text-primary: #1e293b;
    --text-secondary: #334155;
    --text-muted: #64748b;
    --accent: #3b82f6;
    --accent-hover: #2563eb;
    --accent-soft: #e0f2fe;
    --danger: #ef4444;
    --danger-soft: #fee2e2;
    --success: #10b981;
    --border-light: #e2e8f0;
    --btn-bg: #ffffffcc;
    --btn-hover: #f1f5f9;
    --code-bg: #f1f5f9;
    --matrix-input-bg: #ffffff;
    --matrix-input-border: #cbd5e1;
    --result-bg: #f8fafc;
    --footer-bg: rgba(255,255,255,0.6);
    --toggle-bg: #cbd5e1;
}

body.dark {
    --bg-gradient-start: #0f172a;
    --bg-gradient-end: #1e293b;
    --card-bg: rgba(30, 41, 59, 0.7);
    --card-border: rgba(51, 65, 85, 0.5);
    --card-shadow: 0 8px 32px rgba(0, 0, 0, 0.3);
    --text-primary: #f1f5f9;
    --text-secondary: #cbd5e1;
    --text-muted: #94a3b8;
    --accent: #60a5fa;
    --accent-hover: #3b82f6;
    --accent-soft: #1e293b;
    --border-light: #334155;
    --btn-bg: #334155cc;
    --btn-hover: #475569;
    --code-bg: #0f172a;
    --matrix-input-bg: #1e293b;
    --matrix-input-border: #475569;
    --result-bg: #0f172a;
    --footer-bg: rgba(15,23,42,0.8);
    --toggle-bg: #475569;
}

* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
    transition: background-color 0.2s ease, border-color 0.2s ease, color 0.2s ease;
}

body {
    font-family: 'Inter', sans-serif;
    background: linear-gradient(135deg, var(--bg-gradient-start), var(--bg-gradient-end));
    color: var(--text-primary);
    min-height: 100vh;
    line-height: 1.5;
    -webkit-font-smoothing: antialiased;
}

.app-container {
    max-width: 1600px;
    margin: 0 auto;
    padding: 1.5rem;
    min-height: 100vh;
    display: flex;
    flex-direction: column;
    gap: 1.5rem;
}

/* ========== HEADER ========== */
.app-header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    flex-wrap: wrap;
    gap: 1rem;
    backdrop-filter: blur(10px);
    background: var(--card-bg);
    border-radius: 2rem;
    padding: 0.9rem 2rem;
    border: 1px solid var(--card-border);
    box-shadow: var(--card-shadow);
}

.logo-area {
    display: flex;
    align-items: center;
    gap: 1rem;
}

.logo-icon {
    font-size: 2.2rem;
    color: var(--accent);
    filter: drop-shadow(0 2px 4px rgba(0,0,0,0.1));
}

.logo-area h1 {
    font-size: 1.8rem;
    font-weight: 700;
    letter-spacing: 0;
}

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

.tagline {
    font-size: 0.7rem;
    text-transform: uppercase;
    letter-spacing: 1px;
    color: var(--text-muted);
}

.header-controls {
    display: flex;
    gap: 1.5rem;
    align-items: center;
}

.step-toggle-group {
    display: flex;
    align-items: center;
    gap: 0.8rem;
    background: var(--btn-bg);
    padding: 0.4rem 1rem;
    border-radius: 2rem;
    backdrop-filter: blur(4px);
}

.toggle-label {
    font-size: 0.85rem;
    font-weight: 500;
    display: flex;
    align-items: center;
    gap: 0.5rem;
}

.switch {
    position: relative;
    display: inline-block;
    width: 52px;
    height: 26px;
}

.switch input {
    opacity: 0;
    width: 0;
    height: 0;
}

.slider {
    position: absolute;
    cursor: pointer;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    background-color: var(--toggle-bg);
    transition: 0.3s;
    border-radius: 34px;
}

.slider:before {
    position: absolute;
    content: "";
    height: 20px;
    width: 20px;
    left: 3px;
    bottom: 3px;
    background-color: white;
    transition: 0.3s;
    border-radius: 50%;
}

input:checked + .slider {
    background-color: var(--accent);
}

input:checked + .slider:before {
    transform: translateX(26px);
}

.icon-btn {
    background: var(--btn-bg);
    border: 1px solid var(--border-light);
    border-radius: 50%;
    width: 42px;
    height: 42px;
    cursor: pointer;
    color: var(--text-primary);
    font-size: 1.2rem;
    display: flex;
    align-items: center;
    justify-content: center;
    backdrop-filter: blur(4px);
    transition: all 0.2s;
}

.icon-btn:hover {
    background: var(--accent);
    color: white;
    transform: scale(1.05);
}

/* ========== MAIN LAYOUT ========== */
.main-dashboard {
    display: flex;
    flex-direction: column;
    gap: 2rem;
}

.matrices-panel {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(340px, 1fr));
    gap: 1.8rem;
}

.matrix-card {
    background: var(--card-bg);
    backdrop-filter: blur(12px);
    border-radius: 1.75rem;
    padding: 1.5rem;
    border: 1px solid var(--card-border);
    box-shadow: var(--card-shadow);
    transition: transform 0.2s, box-shadow 0.2s;
}

.matrix-card:hover {
    transform: translateY(-3px);
    box-shadow: 0 20px 40px rgba(0, 0, 0, 0.15);
}

.matrix-card-header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    flex-wrap: wrap;
    gap: 1rem;
    margin-bottom: 1.2rem;
}

.matrix-card-header h2 {
    font-size: 1.4rem;
    font-weight: 600;
    display: flex;
    align-items: center;
    gap: 0.5rem;
}

.dimension-controls {
    display: flex;
    gap: 0.8rem;
    align-items: flex-end;
    flex-wrap: wrap;
}

.dim-control {
    display: flex;
    flex-direction: column;
    font-size: 0.7rem;
    font-weight: 500;
    color: var(--text-muted);
}

.dim-control input {
    width: 70px;
    padding: 0.3rem 0.5rem;
    border-radius: 12px;
    border: 1px solid var(--matrix-input-border);
    background: var(--matrix-input-bg);
    color: var(--text-primary);
    text-align: center;
    font-weight: 500;
}

.matrix-grid-container {
    overflow-x: auto;
    margin: 1rem 0;
    max-width: 100%;
}

.matrix-input-grid {
    display: grid;
    gap: 10px;
    justify-content: center;
    padding: 0.5rem 0;
    min-width: fit-content;
}

.matrix-input-grid input {
    width: 70px;
    padding: 10px 5px;
    text-align: center;
    border: 1px solid var(--matrix-input-border);
    border-radius: 12px;
    background: var(--matrix-input-bg);
    color: var(--text-primary);
    font-weight: 500;
    font-size: 0.9rem;
    transition: all 0.15s;
}

.matrix-input-grid input:focus {
    outline: none;
    border-color: var(--accent);
    box-shadow: 0 0 0 2px var(--accent-soft);
}

.matrix-actions {
    display: flex;
    gap: 0.8rem;
    justify-content: flex-end;
    margin-top: 0.8rem;
}

/* Buttons */
.btn-outline, .btn-ghost, .op-btn {
    background: var(--btn-bg);
    border: 1px solid var(--border-light);
    padding: 0.5rem 1rem;
    border-radius: 2rem;
    font-weight: 500;
    font-size: 0.8rem;
    cursor: pointer;
    color: var(--text-primary);
    transition: all 0.2s;
    backdrop-filter: blur(4px);
}

.btn-outline:hover, .btn-ghost:hover, .op-btn:hover {
    background: var(--accent);
    color: white;
    border-color: var(--accent);
    transform: translateY(-2px);
}

.small {
    padding: 0.3rem 0.8rem;
    font-size: 0.75rem;
}

/* Operations Panel */
.operations-panel {
    background: var(--card-bg);
    backdrop-filter: blur(12px);
    border-radius: 1.75rem;
    padding: 1.5rem;
    border: 1px solid var(--card-border);
}

.ops-categories {
    display: flex;
    flex-wrap: wrap;
    gap: 2rem;
    margin-bottom: 2rem;
}

.ops-group {
    flex: 1 1 200px;
}

.ops-group h3 {
    font-size: 0.9rem;
    text-transform: uppercase;
    letter-spacing: 1px;
    color: var(--accent);
    margin-bottom: 1rem;
    display: flex;
    align-items: center;
    gap: 6px;
}

.btn-group {
    display: flex;
    flex-wrap: wrap;
    gap: 0.6rem;
}

.op-btn {
    font-size: 0.8rem;
    padding: 0.45rem 1rem;
    min-height: 38px;
}

.op-btn sup {
    line-height: 0;
}

/* Result Area */
.result-area {
    margin-top: 1rem;
    background: var(--result-bg);
    border-radius: 1.5rem;
    padding: 1.2rem;
}

.result-header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    margin-bottom: 1rem;
}

.result-box {
    background: var(--card-bg);
    border-radius: 1.2rem;
    padding: 1rem;
    font-family: 'Monaco', 'Menlo', monospace;
    font-size: 0.9rem;
    overflow-x: auto;
    white-space: pre-wrap;
    word-break: break-word;
    border-left: 4px solid var(--accent);
    margin-bottom: 1rem;
}

.result-box pre,
.steps-content pre {
    white-space: pre-wrap;
    font-family: inherit;
}

.result-block + .result-block {
    margin-top: 1rem;
}

.result-block h4 {
    color: var(--text-secondary);
    font-family: 'Inter', sans-serif;
    font-size: 0.8rem;
    font-weight: 700;
    letter-spacing: 0;
    margin-bottom: 0.5rem;
    text-transform: uppercase;
}

.matrix-result-wrapper {
    overflow-x: auto;
    padding: 0.25rem 0;
}

.matrix-result-table {
    border-collapse: separate;
    border-spacing: 0;
    color: var(--text-primary);
    font-family: 'Monaco', 'Menlo', monospace;
    font-size: 0.88rem;
    min-width: max-content;
}

.matrix-result-table td {
    background: var(--matrix-input-bg);
    border: 1px solid var(--border-light);
    border-left-width: 0;
    min-width: 72px;
    padding: 0.55rem 0.75rem;
    text-align: right;
    white-space: nowrap;
}

.matrix-result-table tr:first-child td:first-child {
    border-top-left-radius: 10px;
}

.matrix-result-table tr:first-child td:last-child {
    border-top-right-radius: 10px;
}

.matrix-result-table tr:last-child td:first-child {
    border-bottom-left-radius: 10px;
}

.matrix-result-table tr:last-child td:last-child {
    border-bottom-right-radius: 10px;
}

.matrix-result-table td:first-child {
    border-left-width: 1px;
}

.error-text {
    color: var(--danger);
}

.steps-box {
    background: var(--code-bg);
    border-radius: 1rem;
    padding: 1rem;
    margin-top: 0.8rem;
    max-height: 280px;
    overflow-y: auto;
    border: 1px solid var(--border-light);
}

.steps-header {
    font-weight: 600;
    font-size: 0.8rem;
    color: var(--accent);
    margin-bottom: 0.6rem;
    display: flex;
    align-items: center;
    gap: 0.5rem;
}

.steps-content {
    font-size: 0.8rem;
    font-family: monospace;
    white-space: pre-wrap;
    color: var(--text-secondary);
    line-height: 1.5;
}

.error-message {
    background: var(--danger-soft);
    color: var(--danger);
    padding: 0.8rem;
    border-radius: 1rem;
    margin-top: 1rem;
    font-weight: 500;
    border-left: 4px solid var(--danger);
}

.hidden {
    display: none;
}

.loading-badge {
    background: var(--accent-soft);
    padding: 0.3rem 0.8rem;
    border-radius: 2rem;
    font-size: 0.7rem;
    color: var(--accent);
}

.placeholder-text {
    color: var(--text-muted);
    font-style: italic;
}

/* ========== RESPONSIVE ========== */
@media (max-width: 768px) {
    .app-container {
        padding: 0.8rem;
    }
    .matrix-card-header {
        flex-direction: column;
        align-items: flex-start;
    }
    .matrix-input-grid input {
        width: 55px;
        padding: 7px 3px;
        font-size: 0.8rem;
    }
    .ops-categories {
        flex-direction: column;
        gap: 1rem;
    }
    .btn-group {
        justify-content: center;
    }
    .app-header {
        flex-direction: column;
        text-align: center;
    }
    .logo-area {
        justify-content: center;
    }
    .step-toggle-group {
        width: 100%;
        justify-content: center;
    }
    .dim-control input {
        width: 60px;
    }
}

@media (max-width: 420px) {
    .app-container {
        padding: 0.5rem;
    }

    .app-header,
    .matrix-card,
    .operations-panel {
        border-radius: 1rem;
        padding: 1rem;
    }

    .matrices-panel {
        grid-template-columns: minmax(0, 1fr);
    }

    .header-controls,
    .dimension-controls,
    .matrix-actions {
        width: 100%;
        justify-content: center;
    }

    .matrix-input-grid input {
        width: 52px;
    }
}

@media (prefers-reduced-motion: reduce) {
    *,
    *::before,
    *::after {
        transition: none !important;
    }
}

/* Scrollbar modern */
::-webkit-scrollbar {
    width: 8px;
    height: 8px;
}

::-webkit-scrollbar-track {
    background: var(--card-bg);
    border-radius: 10px;
}

::-webkit-scrollbar-thumb {
    background: var(--accent);
    border-radius: 10px;
}

/* Tooltip custom via title attribute */
[data-tooltip] {
    position: relative;
    cursor: help;
}

[data-tooltip]:before {
    content: attr(data-tooltip);
    position: absolute;
    bottom: 125%;
    background: var(--text-primary);
    color: white;
    padding: 4px 8px;
    border-radius: 8px;
    font-size: 0.7rem;
    white-space: nowrap;
    z-index: 10;
    opacity: 0;
    pointer-events: none;
    transition: 0.1s;
}

[data-tooltip]:hover:before {
    opacity: 1;
}

/* Focus states for accessibility */
button:focus-visible, input:focus-visible {
    outline: 3px solid var(--accent);
    outline-offset: 2px;
}

/* print-friendly? not needed but robust */
@media print {
    .app-header, .operations-panel .btn-group, .matrix-actions {
        display: none;
    }
}

/* ===== PREMIUM FOOTER ===== */

.footer {
    margin-top: 4rem;
    padding: 1rem 0 0;
}

.footer-inner {
    position: relative;
    overflow: hidden;
    display: grid;
    grid-template-columns: minmax(0, 1fr) auto;
    align-items: center;
    gap: 2rem;
    padding: 2rem;
    border: 1px solid var(--card-border);
    border-radius: 28px;
    background:
        radial-gradient(circle at top left, rgba(59, 130, 246, 0.22), transparent 34%),
        linear-gradient(135deg, var(--footer-bg), rgba(255, 255, 255, 0.08));
    box-shadow: var(--card-shadow), 0 20px 55px rgba(59, 130, 246, 0.12);
    backdrop-filter: blur(20px);
    -webkit-backdrop-filter: blur(20px);
}

.footer-inner::before {
    content: "";
    position: absolute;
    inset: 0;
    pointer-events: none;
    background: linear-gradient(120deg, transparent 10%, rgba(255, 255, 255, 0.24) 48%, transparent 68%);
    opacity: 0.28;
    transform: translateX(-45%);
}

.footer-brand {
    position: relative;
    z-index: 1;
}

.footer-kicker {
    margin-bottom: 0.45rem;
    color: var(--accent);
    font-size: 0.76rem;
    font-weight: 800;
    letter-spacing: 0.08em;
    text-transform: uppercase;
}

.footer-brand h3 {
    margin-bottom: 0.45rem;
    color: var(--text-primary);
    font-size: clamp(1.35rem, 2vw, 2rem);
    font-weight: 800;
    letter-spacing: 0;
}

.footer-credit {
    color: var(--text-secondary);
    font-size: 0.98rem;
}

.footer-credit span {
    color: var(--accent);
    font-weight: 800;
}

.social-dock {
    position: relative;
    z-index: 1;
    display: grid;
    grid-template-columns: repeat(4, minmax(132px, 1fr));
    gap: 0.85rem;
}

.social {
    position: relative;
    overflow: hidden;
    min-height: 56px;
    display: inline-flex;
    align-items: center;
    justify-content: center;
    gap: 0.7rem;
    padding: 0.95rem 1.1rem;
    border: 1px solid var(--card-border);
    border-radius: 16px;
    color: var(--text-primary);
    background: rgba(255, 255, 255, 0.12);
    box-shadow: inset 0 1px 0 rgba(255, 255, 255, 0.22), 0 10px 28px rgba(15, 23, 42, 0.08);
    text-decoration: none;
    font-size: 0.96rem;
    font-weight: 800;
    line-height: 1;
    white-space: nowrap;
    backdrop-filter: blur(14px);
    -webkit-backdrop-filter: blur(14px);
    transition: transform 0.28s ease, border-color 0.28s ease, box-shadow 0.28s ease, background 0.28s ease, color 0.28s ease;
}

.social::before {
    content: "";
    position: absolute;
    inset: -70% auto auto -40%;
    width: 65%;
    height: 240%;
    background: linear-gradient(120deg, transparent, rgba(255, 255, 255, 0.45), transparent);
    transform: rotate(18deg) translateX(-130%);
    transition: transform 0.55s ease;
}

.social i,
.social span {
    position: relative;
    z-index: 1;
}

.social i {
    font-size: 1.15rem;
}

.social:hover,
.social:focus-visible {
    transform: translateY(-5px);
    color: #ffffff;
}

.social:hover::before,
.social:focus-visible::before {
    transform: rotate(18deg) translateX(235%);
}

.social:focus-visible {
    outline: 3px solid var(--accent);
    outline-offset: 4px;
}

.linkedin:hover,
.linkedin:focus-visible {
    border-color: rgba(0, 119, 181, 0.65);
    background: linear-gradient(135deg, rgba(0, 119, 181, 0.95), rgba(37, 99, 235, 0.82));
    box-shadow: 0 16px 36px rgba(0, 119, 181, 0.34);
}

.github:hover,
.github:focus-visible {
    border-color: rgba(255, 255, 255, 0.38);
    background: linear-gradient(135deg, #111827, #30363d);
    box-shadow: 0 16px 36px rgba(15, 23, 42, 0.34), 0 0 22px rgba(255, 255, 255, 0.18);
}

.insta:hover,
.insta:focus-visible {
    border-color: rgba(225, 48, 108, 0.55);
    background: linear-gradient(135deg, #f09433, #dc2743 48%, #bc1888);
    box-shadow: 0 16px 36px rgba(225, 48, 108, 0.34);
}

.mail:hover,
.mail:focus-visible {
    border-color: rgba(16, 185, 129, 0.55);
    background: linear-gradient(135deg, var(--accent), #10b981);
    box-shadow: 0 16px 36px rgba(16, 185, 129, 0.28), 0 0 24px rgba(59, 130, 246, 0.22);
}

@media (max-width: 1120px) {
    .footer-inner {
        grid-template-columns: 1fr;
        text-align: center;
    }

    .social-dock {
        width: 100%;
        grid-template-columns: repeat(2, minmax(0, 1fr));
    }
}

@media (max-width: 560px) {
    .footer {
        margin-top: 2.5rem;
    }

    .footer-inner {
        padding: 1.35rem;
        border-radius: 22px;
    }

    .footer-kicker {
        font-size: 0.68rem;
    }

    .footer-credit {
        font-size: 0.9rem;
    }

    .social-dock {
        grid-template-columns: 1fr;
    }

    .social {
        width: 100%;
        min-height: 54px;
    }
}