/* ═══════════════════════════════════════════════════════════════════
   SIMPLEX SOLVER — Premium Animated Interface
   ═══════════════════════════════════════════════════════════════════ */

/* ── Reset & Base ────────────────────────────────────────────────── */
*, *::before, *::after { margin: 0; padding: 0; box-sizing: border-box; }

:root {
    /* Core Palette */
    --bg-deep: #06060f;
    --bg-dark: #0a0a1a;
    --bg-card: rgba(15, 15, 35, 0.6);
    --bg-card-hover: rgba(20, 20, 50, 0.8);

    /* Accent */
    --indigo: #6366f1;
    --purple: #a855f7;
    --violet: #8b5cf6;
    --pink: #ec4899;
    --cyan: #22d3ee;
    --emerald: #10b981;
    --amber: #f59e0b;
    --rose: #f43f5e;

    /* Gradient */
    --grad-primary: linear-gradient(135deg, #6366f1, #a855f7);
    --grad-hero: linear-gradient(135deg, #6366f1 0%, #a855f7 50%, #ec4899 100%);
    --grad-green: linear-gradient(135deg, #10b981, #22d3ee);
    --grad-amber: linear-gradient(135deg, #f59e0b, #f43f5e);

    /* Text */
    --text-primary: #f1f5f9;
    --text-secondary: #94a3b8;
    --text-muted: #64748b;
    --text-dim: #475569;

    /* Border */
    --border: rgba(99, 102, 241, 0.15);
    --border-hover: rgba(99, 102, 241, 0.4);

    /* Glow */
    --glow-indigo: 0 0 30px rgba(99, 102, 241, 0.3);
    --glow-purple: 0 0 30px rgba(168, 85, 247, 0.3);

    /* Misc */
    --radius: 16px;
    --radius-sm: 10px;
    --radius-xs: 6px;
    --transition: 0.3s cubic-bezier(0.4, 0, 0.2, 1);
    --transition-slow: 0.6s cubic-bezier(0.4, 0, 0.2, 1);
}

html { scroll-behavior: smooth; }

body {
    font-family: 'Inter', -apple-system, BlinkMacSystemFont, sans-serif;
    background: var(--bg-deep);
    color: var(--text-primary);
    overflow-x: hidden;
    min-height: 100vh;
    line-height: 1.6;
}

/* ── Particle Canvas ─────────────────────────────────────────────── */
#particles {
    position: fixed;
    inset: 0;
    z-index: 0;
    pointer-events: none;
}

/* ── Floating Orbs ───────────────────────────────────────────────── */
.orb {
    position: fixed;
    border-radius: 50%;
    filter: blur(80px);
    opacity: 0.15;
    pointer-events: none;
    z-index: 0;
    animation: orbit 20s ease-in-out infinite;
}
.orb-1 {
    width: 600px; height: 600px;
    background: var(--indigo);
    top: -200px; left: -100px;
}
.orb-2 {
    width: 500px; height: 500px;
    background: var(--purple);
    bottom: -150px; right: -100px;
    animation-delay: -7s;
    animation-duration: 25s;
}
.orb-3 {
    width: 400px; height: 400px;
    background: var(--pink);
    top: 50%; left: 50%;
    transform: translate(-50%, -50%);
    animation-delay: -14s;
    animation-duration: 30s;
}

@keyframes orbit {
    0%, 100% { transform: translate(0, 0) scale(1); }
    25% { transform: translate(60px, -40px) scale(1.1); }
    50% { transform: translate(-40px, 60px) scale(0.9); }
    75% { transform: translate(40px, 40px) scale(1.05); }
}

/* ── Header ──────────────────────────────────────────────────────── */
.header {
    position: fixed; top: 0; left: 0; right: 0;
    z-index: 100;
    padding: 0 2rem;
    background: rgba(6, 6, 15, 0.7);
    backdrop-filter: blur(20px) saturate(1.5);
    border-bottom: 1px solid var(--border);
    transition: var(--transition);
}
.header.scrolled {
    background: rgba(6, 6, 15, 0.95);
    box-shadow: 0 4px 30px rgba(0, 0, 0, 0.5);
}
.header-inner {
    max-width: 1200px; margin: 0 auto;
    display: flex; align-items: center; justify-content: space-between;
    height: 72px;
}
.logo {
    display: flex; align-items: center; gap: 12px;
    cursor: pointer;
    transition: var(--transition);
}
.logo:hover { transform: scale(1.03); }
.logo-icon { width: 40px; height: 40px; }
.logo-icon svg { width: 100%; height: 100%; }
.logo-text {
    font-size: 1.3rem; font-weight: 700;
    letter-spacing: -0.02em;
}
.logo-accent {
    background: var(--grad-primary);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
}

.nav-links { display: flex; gap: 8px; }
.nav-link {
    padding: 8px 18px;
    border-radius: 99px;
    font-size: 0.875rem;
    font-weight: 500;
    color: var(--text-secondary);
    text-decoration: none;
    transition: var(--transition);
    position: relative;
}
.nav-link:hover { color: var(--text-primary); background: rgba(99, 102, 241, 0.1); }
.nav-link.active {
    color: white;
    background: rgba(99, 102, 241, 0.2);
    box-shadow: inset 0 0 0 1px rgba(99, 102, 241, 0.3);
}

.header-right { display: flex; align-items: center; gap: 16px; }
.lang-switch {
    display: flex;
    padding: 3px;
    border-radius: 99px;
    background: rgba(99, 102, 241, 0.12);
    border: 1px solid rgba(99, 102, 241, 0.25);
    flex-shrink: 0;
}
.lang-btn {
    border: none;
    background: transparent;
    color: var(--text-secondary);
    font-family: inherit;
    font-size: 0.75rem;
    font-weight: 700;
    letter-spacing: 0.04em;
    padding: 6px 12px;
    border-radius: 99px;
    cursor: pointer;
    transition: var(--transition);
}
.lang-btn:hover { color: var(--text-primary); }
.lang-btn.active {
    color: white;
    background: var(--grad-primary);
    box-shadow: var(--glow-indigo);
}

/* ── Hero ─────────────────────────────────────────────────────────── */
.hero {
    position: relative;
    z-index: 1;
    min-height: 100vh;
    display: flex;
    align-items: center;
    justify-content: center;
    padding: 120px 2rem 80px;
    gap: 80px;
}
.hero-content { max-width: 560px; }
.hero-badge {
    display: inline-flex; align-items: center; gap: 8px;
    padding: 6px 16px;
    border-radius: 99px;
    font-size: 0.8rem; font-weight: 600;
    color: var(--indigo);
    background: rgba(99, 102, 241, 0.1);
    border: 1px solid rgba(99, 102, 241, 0.2);
    margin-bottom: 24px;
    animation: fadeInUp 0.8s ease-out;
}
.badge-dot {
    width: 6px; height: 6px;
    border-radius: 50%;
    background: var(--indigo);
    animation: pulse-dot 2s ease-in-out infinite;
}
@keyframes pulse-dot {
    0%, 100% { opacity: 1; transform: scale(1); }
    50% { opacity: 0.5; transform: scale(1.5); }
}

.hero-title {
    font-size: 3.5rem;
    font-weight: 800;
    line-height: 1.1;
    letter-spacing: -0.03em;
    margin-bottom: 20px;
    animation: fadeInUp 0.8s ease-out 0.1s both;
}
.gradient-text {
    background: var(--grad-hero);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
}
.hero-subtitle {
    font-size: 1.1rem;
    color: var(--text-secondary);
    line-height: 1.7;
    margin-bottom: 36px;
    animation: fadeInUp 0.8s ease-out 0.2s both;
}
.btn-hero {
    display: inline-flex; align-items: center; gap: 10px;
    padding: 16px 36px;
    border-radius: 99px;
    font-family: inherit;
    font-size: 1rem; font-weight: 600;
    color: white;
    background: var(--grad-primary);
    border: none; cursor: pointer;
    position: relative;
    overflow: hidden;
    transition: var(--transition);
    animation: fadeInUp 0.8s ease-out 0.3s both;
    box-shadow: 0 4px 30px rgba(99, 102, 241, 0.4);
}
.btn-hero::before {
    content: '';
    position: absolute; inset: 0;
    background: linear-gradient(135deg, rgba(255,255,255,0.2), transparent);
    opacity: 0;
    transition: var(--transition);
}
.btn-hero:hover { transform: translateY(-3px) scale(1.03); box-shadow: 0 8px 40px rgba(99, 102, 241, 0.5); }
.btn-hero:hover::before { opacity: 1; }
.btn-hero:active { transform: translateY(-1px) scale(1); }

/* Hero Visual */
.hero-visual {
    perspective: 1200px;
    animation: fadeInUp 1s ease-out 0.4s both;
}
.hero-3d-card {
    width: 380px;
    transform: rotateY(-12deg) rotateX(8deg);
    transition: transform 0.6s ease;
    transform-style: preserve-3d;
    animation: float 6s ease-in-out infinite;
}
.hero-3d-card:hover {
    transform: rotateY(0) rotateX(0);
}
.card-face {
    background: var(--bg-card);
    border: 1px solid var(--border);
    border-radius: var(--radius);
    padding: 24px;
    backdrop-filter: blur(20px);
    box-shadow: var(--glow-indigo), 0 20px 60px rgba(0, 0, 0, 0.5);
}
.mini-tableau { font-family: 'JetBrains Mono', monospace; font-size: 0.85rem; }
.mt-row {
    display: grid;
    grid-template-columns: 50px repeat(5, 1fr);
    gap: 4px;
    padding: 8px 4px;
    border-bottom: 1px solid rgba(99, 102, 241, 0.1);
    transition: var(--transition);
}
.mt-row:hover { background: rgba(99, 102, 241, 0.05); }
.mt-row span { text-align: center; }
.mt-header {
    color: var(--indigo);
    font-weight: 600;
    border-bottom: 2px solid rgba(99, 102, 241, 0.2);
}
.mt-obj { color: var(--amber); border-bottom: none; }
.pivot-glow {
    color: var(--cyan) !important;
    text-shadow: 0 0 12px rgba(34, 211, 238, 0.6);
    font-weight: 700;
    animation: pulse-glow 2s ease-in-out infinite;
}
@keyframes pulse-glow {
    0%, 100% { text-shadow: 0 0 12px rgba(34, 211, 238, 0.6); }
    50% { text-shadow: 0 0 24px rgba(34, 211, 238, 1); }
}

@keyframes float {
    0%, 100% { transform: rotateY(-12deg) rotateX(8deg) translateY(0); }
    50% { transform: rotateY(-12deg) rotateX(8deg) translateY(-15px); }
}

/* ── Animations ──────────────────────────────────────────────────── */
@keyframes fadeInUp {
    from { opacity: 0; transform: translateY(30px); }
    to { opacity: 1; transform: translateY(0); }
}
@keyframes fadeIn {
    from { opacity: 0; }
    to { opacity: 1; }
}
@keyframes scaleIn {
    from { opacity: 0; transform: scale(0.9); }
    to { opacity: 1; transform: scale(1); }
}
@keyframes slideInLeft {
    from { opacity: 0; transform: translateX(-40px); }
    to { opacity: 1; transform: translateX(0); }
}
@keyframes slideInRight {
    from { opacity: 0; transform: translateX(40px); }
    to { opacity: 1; transform: translateX(0); }
}
@keyframes shimmer {
    0% { background-position: -200% 0; }
    100% { background-position: 200% 0; }
}

/* ── Sections ────────────────────────────────────────────────────── */
.section {
    position: relative;
    z-index: 1;
    max-width: 1200px;
    margin: 0 auto;
    padding: 80px 2rem 60px;
}
.section-header {
    text-align: center;
    margin-bottom: 50px;
}
.section-number {
    font-size: 0.875rem;
    font-weight: 700;
    color: var(--indigo);
    letter-spacing: 0.1em;
    margin-bottom: 12px;
    font-family: 'JetBrains Mono', monospace;
}
.section-title {
    font-size: 2.5rem;
    font-weight: 800;
    letter-spacing: -0.03em;
    margin-bottom: 12px;
}
.section-desc {
    color: var(--text-secondary);
    font-size: 1.05rem;
}

/* ── Glass Cards ─────────────────────────────────────────────────── */
.glass-card {
    background: var(--bg-card);
    border: 1px solid var(--border);
    border-radius: var(--radius);
    padding: 32px;
    backdrop-filter: blur(20px);
    transition: var(--transition);
    position: relative;
    overflow: hidden;
}
.glass-card::before {
    content: '';
    position: absolute; top: 0; left: 0; right: 0;
    height: 1px;
    background: linear-gradient(90deg, transparent, rgba(99, 102, 241, 0.5), transparent);
    opacity: 0;
    transition: var(--transition);
}
.glass-card:hover::before { opacity: 1; }
.glass-card:hover {
    border-color: var(--border-hover);
    box-shadow: var(--glow-indigo);
}

.card-header {
    display: flex; align-items: center; gap: 14px;
    margin-bottom: 28px;
}
.card-header h3 { font-size: 1.15rem; font-weight: 700; }
.card-icon {
    width: 42px; height: 42px;
    border-radius: var(--radius-sm);
    display: grid; place-items: center;
    background: rgba(99, 102, 241, 0.12);
    color: var(--indigo);
}
.card-icon svg { width: 22px; height: 22px; }
.card-icon.purple { background: rgba(168, 85, 247, 0.12); color: var(--purple); }
.card-icon.green { background: rgba(16, 185, 129, 0.12); color: var(--emerald); }
.card-icon.amber { background: rgba(245, 158, 11, 0.12); color: var(--amber); }

/* ── Input Grid ──────────────────────────────────────────────────── */
.input-grid {
    display: grid;
    grid-template-columns: 1fr 1.4fr;
    gap: 28px;
    margin-bottom: 28px;
}
@media (max-width: 900px) {
    .input-grid { grid-template-columns: 1fr; }
    .hero { flex-direction: column; text-align: center; gap: 40px; padding-top: 100px; }
    .hero-title { font-size: 2.5rem; }
    .hero-3d-card { width: 320px; }
}

/* ── Toggle ──────────────────────────────────────────────────────── */
.toggle-group {
    display: flex; gap: 6px;
    background: rgba(0, 0, 0, 0.3);
    border-radius: var(--radius-sm);
    padding: 4px;
}
.toggle-btn {
    flex: 1;
    display: flex; align-items: center; justify-content: center; gap: 6px;
    padding: 10px 20px;
    border: none;
    border-radius: 8px;
    font-family: inherit;
    font-size: 0.875rem;
    font-weight: 600;
    color: var(--text-muted);
    background: transparent;
    cursor: pointer;
    transition: var(--transition);
}
.toggle-btn:hover { color: var(--text-secondary); }
.toggle-btn.active {
    color: white;
    background: var(--grad-primary);
    box-shadow: 0 4px 15px rgba(99, 102, 241, 0.4);
}

/* ── Stepper ─────────────────────────────────────────────────────── */
.stepper {
    display: flex; align-items: center;
    background: rgba(0, 0, 0, 0.3);
    border-radius: var(--radius-sm);
    border: 1px solid var(--border);
    overflow: hidden;
}
.stepper-btn {
    width: 44px; height: 44px;
    border: none;
    background: transparent;
    color: var(--text-secondary);
    font-size: 1.2rem;
    cursor: pointer;
    transition: var(--transition);
    font-family: inherit;
}
.stepper-btn:hover { color: white; background: rgba(99, 102, 241, 0.2); }
.stepper input {
    width: 60px; height: 44px;
    border: none;
    background: transparent;
    color: white;
    text-align: center;
    font-family: 'JetBrains Mono', monospace;
    font-size: 1.1rem;
    font-weight: 600;
    border-left: 1px solid var(--border);
    border-right: 1px solid var(--border);
}

/* ── Form ────────────────────────────────────────────────────────── */
.config-form { display: flex; flex-direction: column; gap: 20px; }
.form-group { display: flex; flex-direction: column; gap: 8px; }
.form-group label {
    font-size: 0.8rem;
    font-weight: 600;
    text-transform: uppercase;
    letter-spacing: 0.08em;
    color: var(--text-secondary);
}
.form-row { display: grid; grid-template-columns: 1fr 1fr; gap: 16px; }

/* ── Buttons ─────────────────────────────────────────────────────── */
.btn-primary {
    display: inline-flex; align-items: center; justify-content: center; gap: 8px;
    padding: 14px 28px;
    border: none;
    border-radius: var(--radius-sm);
    font-family: inherit;
    font-size: 0.9rem; font-weight: 600;
    color: white;
    background: var(--grad-primary);
    cursor: pointer;
    transition: var(--transition);
    box-shadow: 0 4px 20px rgba(99, 102, 241, 0.3);
}
.btn-primary:hover { transform: translateY(-2px); box-shadow: 0 6px 30px rgba(99, 102, 241, 0.5); }
.btn-primary:active { transform: translateY(0); }
.btn-primary:disabled {
    opacity: 0.5; cursor: not-allowed;
    transform: none !important; box-shadow: none !important;
}

.btn-secondary {
    display: inline-flex; align-items: center; justify-content: center; gap: 8px;
    padding: 12px 24px;
    border: 1px solid var(--border);
    border-radius: var(--radius-sm);
    font-family: inherit;
    font-size: 0.875rem; font-weight: 600;
    color: var(--text-secondary);
    background: transparent;
    cursor: pointer;
    transition: var(--transition);
}
.btn-secondary:hover {
    color: white;
    border-color: var(--border-hover);
    background: rgba(99, 102, 241, 0.1);
}

.glow-btn {
    position: relative;
    overflow: hidden;
}
.glow-btn::after {
    content: '';
    position: absolute; inset: -2px;
    background: var(--grad-hero);
    border-radius: inherit;
    z-index: -1;
    opacity: 0;
    filter: blur(12px);
    transition: var(--transition);
}
.glow-btn:hover::after { opacity: 0.6; }

/* ── Coefficient Input ───────────────────────────────────────────── */
.obj-section, .con-section { margin-bottom: 24px; }
.section-label {
    font-size: 0.75rem;
    font-weight: 700;
    text-transform: uppercase;
    letter-spacing: 0.1em;
    color: var(--indigo);
    margin-bottom: 14px;
    display: flex; align-items: center; gap: 8px;
}
.section-label::after {
    content: '';
    flex: 1;
    height: 1px;
    background: linear-gradient(90deg, rgba(99, 102, 241, 0.3), transparent);
}

.coeff-row {
    display: flex; align-items: center; gap: 8px;
    margin-bottom: 10px;
    flex-wrap: wrap;
}
.coeff-input-wrap {
    display: flex; align-items: center; gap: 4px;
}
.coeff-input {
    width: 72px; height: 40px;
    border: 1px solid var(--border);
    border-radius: var(--radius-xs);
    background: rgba(0, 0, 0, 0.4);
    color: white;
    text-align: center;
    font-family: 'JetBrains Mono', monospace;
    font-size: 0.9rem;
    transition: var(--transition);
    outline: none;
}
.coeff-input:focus {
    border-color: var(--indigo);
    box-shadow: 0 0 0 3px rgba(99, 102, 241, 0.2);
}
.coeff-input.pivot-highlight {
    border-color: var(--cyan);
    box-shadow: 0 0 0 3px rgba(34, 211, 238, 0.3);
    animation: pulse-border 1.5s ease-in-out infinite;
}
@keyframes pulse-border {
    0%, 100% { box-shadow: 0 0 0 3px rgba(34, 211, 238, 0.2); }
    50% { box-shadow: 0 0 0 6px rgba(34, 211, 238, 0.4); }
}

.var-label {
    font-family: 'JetBrains Mono', monospace;
    font-size: 0.85rem;
    color: var(--text-secondary);
    min-width: 22px;
}
.op-label {
    font-size: 0.9rem;
    color: var(--text-muted);
    margin: 0 2px;
}
.con-label {
    font-family: 'JetBrains Mono', monospace;
    font-size: 0.75rem;
    font-weight: 600;
    color: var(--purple);
    min-width: 80px;
}
.bi-input {
    width: 80px; height: 40px;
    border: 1px solid var(--border);
    border-radius: var(--radius-xs);
    background: rgba(0, 0, 0, 0.4);
    color: var(--amber);
    text-align: center;
    font-family: 'JetBrains Mono', monospace;
    font-size: 0.9rem;
    transition: var(--transition);
    outline: none;
}
.bi-input:focus {
    border-color: var(--amber);
    box-shadow: 0 0 0 3px rgba(245, 158, 11, 0.2);
}

.leq-symbol {
    color: var(--emerald);
    font-weight: 700;
    font-size: 1rem;
    margin: 0 4px;
}

/* ── Problem Preview ─────────────────────────────────────────────── */
.preview-card { text-align: center; }
.problem-preview {
    font-family: 'JetBrains Mono', monospace;
    font-size: 1rem;
    line-height: 2.2;
    padding: 24px;
    background: rgba(0, 0, 0, 0.3);
    border-radius: var(--radius-sm);
    border: 1px solid rgba(99, 102, 241, 0.1);
    margin-bottom: 24px;
    text-align: left;
}
.preview-actions {
    display: flex; gap: 12px; justify-content: center;
}

/* ── Progress Bar ────────────────────────────────────────────────── */
.progress-container {
    margin-bottom: 40px;
    animation: fadeInUp 0.5s ease-out;
}
.progress-bar {
    height: 6px;
    background: rgba(99, 102, 241, 0.15);
    border-radius: 99px;
    overflow: hidden;
    margin-bottom: 12px;
}
.progress-fill {
    height: 100%;
    width: 0%;
    background: var(--grad-primary);
    border-radius: 99px;
    transition: width 0.8s cubic-bezier(0.4, 0, 0.2, 1);
    position: relative;
}
.progress-fill::after {
    content: '';
    position: absolute; right: 0; top: -2px;
    width: 10px; height: 10px;
    border-radius: 50%;
    background: white;
    box-shadow: 0 0 10px var(--indigo);
}
.progress-label {
    text-align: center;
    font-size: 0.85rem;
    color: var(--text-secondary);
}

/* ── Iteration Card ──────────────────────────────────────────────── */
.iteration-card {
    background: var(--bg-card);
    border: 1px solid var(--border);
    border-radius: var(--radius);
    margin-bottom: 20px;
    overflow: hidden;
    animation: scaleIn 0.5s ease-out;
}
.iter-header {
    display: flex; align-items: center; justify-content: space-between;
    padding: 18px 24px;
    background: rgba(99, 102, 241, 0.05);
    border-bottom: 1px solid var(--border);
    cursor: pointer;
    transition: var(--transition);
}
.iter-header:hover { background: rgba(99, 102, 241, 0.1); }
.iter-title {
    display: flex; align-items: center; gap: 12px;
    font-weight: 700;
}
.iter-badge {
    display: inline-flex; align-items: center; justify-content: center;
    width: 32px; height: 32px;
    border-radius: 8px;
    font-size: 0.85rem; font-weight: 700;
    background: var(--grad-primary);
    color: white;
    font-family: 'JetBrains Mono', monospace;
}
.iter-info {
    display: flex; gap: 16px;
}
.iter-tag {
    font-size: 0.75rem;
    font-weight: 600;
    padding: 4px 12px;
    border-radius: 99px;
    background: rgba(16, 185, 129, 0.1);
    color: var(--emerald);
    border: 1px solid rgba(16, 185, 129, 0.2);
}
.iter-tag.entering { background: rgba(34, 211, 238, 0.1); color: var(--cyan); border-color: rgba(34, 211, 238, 0.2); }
.iter-tag.leaving { background: rgba(244, 63, 94, 0.1); color: var(--rose); border-color: rgba(244, 63, 94, 0.2); }

.iter-body {
    padding: 24px;
    overflow-x: auto;
}

/* ── Simplex Table ───────────────────────────────────────────────── */
.simplex-table {
    width: 100%;
    border-collapse: collapse;
    font-family: 'JetBrains Mono', monospace;
    font-size: 0.85rem;
}
.simplex-table th {
    padding: 12px 16px;
    text-align: center;
    color: var(--indigo);
    font-weight: 600;
    border-bottom: 2px solid rgba(99, 102, 241, 0.2);
    white-space: nowrap;
}
.simplex-table td {
    padding: 12px 16px;
    text-align: center;
    border-bottom: 1px solid rgba(99, 102, 241, 0.08);
    transition: all 0.4s ease;
}
.simplex-table tr:hover td { background: rgba(99, 102, 241, 0.04); }
.simplex-table .base-cell {
    font-weight: 600;
    color: var(--purple);
}
.simplex-table .obj-row td {
    border-top: 2px solid rgba(245, 158, 11, 0.3);
    color: var(--amber);
    font-weight: 600;
}
.simplex-table .pivot-cell {
    color: var(--cyan) !important;
    font-weight: 700;
    position: relative;
    background: rgba(34, 211, 238, 0.08) !important;
    box-shadow: inset 0 0 0 2px rgba(34, 211, 238, 0.4);
    border-radius: 4px;
    text-shadow: 0 0 8px rgba(34, 211, 238, 0.5);
}
.simplex-table .pivot-col {
    background: rgba(34, 211, 238, 0.03);
}
.simplex-table .pivot-row td {
    background: rgba(34, 211, 238, 0.03);
}
.simplex-table .ratio-cell {
    color: var(--text-muted);
    font-size: 0.8rem;
}
.simplex-table .bi-cell {
    color: var(--amber);
}

/* ── Results ─────────────────────────────────────────────────────── */
.results-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(260px, 1fr));
    gap: 20px;
}
.result-card {
    background: var(--bg-card);
    border: 1px solid var(--border);
    border-radius: var(--radius);
    padding: 28px;
    text-align: center;
    animation: scaleIn 0.5s ease-out both;
    position: relative;
    overflow: hidden;
}
.result-card::after {
    content: '';
    position: absolute; top: 0; left: 0; right: 0;
    height: 3px;
}
.result-card.z-card::after { background: var(--grad-primary); }
.result-card.status-card::after { background: var(--grad-green); }
.result-card.var-card::after { background: var(--grad-amber); }

.result-label {
    font-size: 0.75rem;
    font-weight: 700;
    text-transform: uppercase;
    letter-spacing: 0.1em;
    color: var(--text-muted);
    margin-bottom: 12px;
}
.result-value {
    font-family: 'JetBrains Mono', monospace;
    font-size: 2rem;
    font-weight: 800;
    margin-bottom: 4px;
}
.result-value.z-val { color: var(--indigo); }
.result-value.status-val { color: var(--emerald); font-size: 1.1rem; }
.result-value.var-val { color: var(--amber); font-size: 1.3rem; }

.result-sub {
    font-size: 0.8rem;
    color: var(--text-muted);
}

/* ── Status Badge ────────────────────────────────────────────────── */
.status-icon {
    display: inline-flex; align-items: center; justify-content: center;
    width: 56px; height: 56px;
    border-radius: 50%;
    margin-bottom: 16px;
}
.status-icon.success { background: rgba(16, 185, 129, 0.15); }
.status-icon.warning { background: rgba(245, 158, 11, 0.15); }
.status-icon.error { background: rgba(244, 63, 94, 0.15); }

/* ── Toast ────────────────────────────────────────────────────────── */
.toast-container {
    position: fixed;
    top: 90px; right: 24px;
    z-index: 1000;
    display: flex; flex-direction: column; gap: 10px;
}
.toast {
    display: flex; align-items: center; gap: 12px;
    padding: 14px 20px;
    border-radius: var(--radius-sm);
    background: rgba(15, 15, 35, 0.95);
    border: 1px solid var(--border);
    backdrop-filter: blur(20px);
    box-shadow: 0 10px 40px rgba(0, 0, 0, 0.5);
    font-size: 0.875rem;
    animation: slideInRight 0.4s ease-out;
    max-width: 360px;
}
.toast.success { border-color: rgba(16, 185, 129, 0.4); }
.toast.error { border-color: rgba(244, 63, 94, 0.4); }
.toast.info { border-color: rgba(99, 102, 241, 0.4); }
.toast-icon {
    width: 20px; height: 20px;
    flex-shrink: 0;
}

/* ── Hidden ──────────────────────────────────────────────────────── */
.hidden { display: none !important; }

/* ── Footer ──────────────────────────────────────────────────────── */
.footer {
    position: relative;
    z-index: 1;
    text-align: center;
    padding: 40px 2rem;
    color: var(--text-dim);
    font-size: 0.85rem;
    border-top: 1px solid var(--border);
}

/* ── Scrollbar ───────────────────────────────────────────────────── */
::-webkit-scrollbar { width: 8px; height: 8px; }
::-webkit-scrollbar-track { background: transparent; }
::-webkit-scrollbar-thumb {
    background: rgba(99, 102, 241, 0.3);
    border-radius: 99px;
}
::-webkit-scrollbar-thumb:hover { background: rgba(99, 102, 241, 0.5); }

/* ── Iter chevron ────────────────────────────────────────────────── */
.iter-chevron {
    width: 20px; height: 20px;
    color: var(--text-muted);
    transition: transform 0.3s ease;
}
.iter-header.collapsed .iter-chevron {
    transform: rotate(-90deg);
}
.iter-body.collapsed {
    display: none;
}

/* ── Bland Notice ────────────────────────────────────────────────── */
.bland-notice {
    display: flex; align-items: center; gap: 10px;
    padding: 12px 18px;
    background: rgba(245, 158, 11, 0.08);
    border: 1px solid rgba(245, 158, 11, 0.2);
    border-radius: var(--radius-sm);
    margin-top: 12px;
    font-size: 0.85rem;
    color: var(--amber);
    animation: fadeIn 0.3s ease;
}

/* ── Example Dropdown ────────────────────────────────────────────── */
.example-dropdown {
    position: relative;
    display: inline-block;
}
/* Allow dropdown to escape the card boundaries and stay above footer */
.preview-card {
    overflow: visible !important;
    z-index: 10;
}

.dropdown-content {
    display: none;
    position: absolute;
    bottom: 100%;
    left: 0;
    width: 220px;
    background: var(--bg-card);
    backdrop-filter: blur(20px);
    border: 1px solid var(--border);
    border-radius: var(--radius-sm);
    box-shadow: 0 10px 40px rgba(0, 0, 0, 0.5);
    z-index: 1000;
    margin-bottom: 8px;
    overflow: hidden;
    animation: fadeInUp 0.3s ease-out;
}
.dropdown-content a {
    color: var(--text-secondary);
    padding: 12px 16px;
    text-decoration: none;
    display: block;
    font-size: 0.875rem;
    font-weight: 500;
    transition: var(--transition);
}
.dropdown-content a:hover {
    background: rgba(99, 102, 241, 0.1);
    color: white;
}
.dropdown-content.show {
    display: block;
}


/* ── Responsive ──────────────────────────────────────────────────── */

@media (max-width: 600px) {
    .section { padding: 60px 1rem 40px; }
    .section-title { font-size: 1.8rem; }
    .glass-card { padding: 20px; }
    .input-grid { grid-template-columns: 1fr; }
    .hero-title { font-size: 2rem; }
    .hero-visual { display: none; }
    .results-grid { grid-template-columns: 1fr; }
    .preview-actions { flex-direction: column; }
    .nav-links { display: none; }
    .header { padding: 0 1rem; }
}

/* ── Degeneracy animation ────────────────────────────────────────── */
.degen-flash {
    animation: flashAmber 0.6s ease 3;
}
@keyframes flashAmber {
    0%, 100% { background: transparent; }
    50% { background: rgba(245, 158, 11, 0.08); }
}

/* ── Loading spinner ─────────────────────────────────────────────── */
.spinner {
    width: 20px; height: 20px;
    border: 2px solid rgba(255,255,255,0.2);
    border-top-color: white;
    border-radius: 50%;
    animation: spin 0.6s linear infinite;
    display: inline-block;
}
@keyframes spin {
    to { transform: rotate(360deg); }
}

/* Cells value animation */
.cell-updated {
    animation: cellFlash 0.6s ease;
}
@keyframes cellFlash {
    0% { background: rgba(99, 102, 241, 0.3); }
    100% { background: transparent; }
}