/* ==================== VARIABLES ==================== */
:root {
    --bg-primary: #0a0a0f;
    --bg-secondary: #111118;
    --bg-card: rgba(255, 255, 255, 0.04);
    --bg-card-hover: rgba(255, 255, 255, 0.08);
    --text-primary: #e8e8ed;
    --text-secondary: #9999a8;
    --accent: #4fc3f7;
    --accent-dark: #0288d1;
    --accent-gradient: linear-gradient(135deg, #4fc3f7, #0288d1);
    --border: rgba(255, 255, 255, 0.08);
    --font: 'Inter', -apple-system, BlinkMacSystemFont, sans-serif;
    --radius: 12px;
    --transition: 0.3s ease;
    --green: #66bb6a;
    --red: #ef5350;
}

/* ==================== RESET ==================== */
*,
*::before,
*::after {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

html {
    scroll-behavior: smooth;
    scroll-padding-top: 80px;
}

body {
    font-family: var(--font);
    background: var(--bg-primary);
    color: var(--text-primary);
    line-height: 1.7;
    -webkit-font-smoothing: antialiased;
}

a {
    color: var(--accent);
    text-decoration: none;
    transition: color var(--transition);
}

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

ul {
    list-style: none;
}

/* ==================== UTILITIES ==================== */
.container {
    max-width: 1100px;
    margin: 0 auto;
    padding: 0 24px;
}

.section {
    padding: 100px 0;
}

.section-alt {
    background: var(--bg-secondary);
}

.section-title {
    font-size: 2rem;
    font-weight: 700;
    margin-bottom: 48px;
    text-align: center;
    position: relative;
}

.section-title::after {
    content: '';
    display: block;
    width: 50px;
    height: 3px;
    background: var(--accent-gradient);
    margin: 12px auto 0;
    border-radius: 2px;
}

/* ==================== BUTTONS ==================== */
.btn {
    display: inline-block;
    padding: 12px 28px;
    border-radius: 8px;
    font-weight: 600;
    font-size: 0.95rem;
    cursor: pointer;
    transition: all var(--transition);
    border: none;
    font-family: var(--font);
}

.btn-primary {
    background: var(--accent-gradient);
    color: #000;
}

.btn-primary:hover {
    transform: translateY(-2px);
    box-shadow: 0 8px 25px rgba(79, 195, 247, 0.3);
    color: #000;
}

.btn-outline {
    background: transparent;
    border: 1px solid var(--accent);
    color: var(--accent);
}

.btn-outline:hover {
    background: var(--accent);
    color: #000;
}

/* ==================== NAVBAR ==================== */
.navbar {
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    z-index: 1000;
    padding: 16px 0;
    background: transparent;
    transition: all var(--transition);
}

.navbar.scrolled {
    background: rgba(10, 10, 15, 0.95);
    backdrop-filter: blur(20px);
    padding: 10px 0;
    box-shadow: 0 2px 20px rgba(0, 0, 0, 0.3);
}

.nav-container {
    width: 100%;
    padding: 0 24px;
    display: flex;
    align-items: center;
    justify-content: space-between;
    position: relative;
}

.nav-logo {
    font-size: 1.4rem;
    font-weight: 700;
    color: var(--text-primary);
    display: flex;
    align-items: center;
    gap: 10px;
    flex-shrink: 0;
}

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

.logo-icon {
    font-size: 1.5rem;
    color: var(--accent);
}

.nav-links {
    display: flex;
    gap: 32px;
    align-items: center;
    position: absolute;
    left: 50%;
    transform: translateX(-50%);
}

.nav-links a {
    color: var(--text-secondary);
    font-size: 0.9rem;
    font-weight: 500;
    position: relative;
    padding: 4px 0;
}

.nav-links a::after {
    content: '';
    position: absolute;
    bottom: -2px;
    left: 0;
    width: 0;
    height: 2px;
    background: var(--accent);
    transition: width var(--transition);
}

.nav-links a:hover,
.nav-links a.active {
    color: var(--text-primary);
}

.nav-links a:hover::after,
.nav-links a.active::after {
    width: 100%;
}

/* Hamburger */
.nav-toggle {
    display: none;
    background: none;
    border: none;
    cursor: pointer;
    padding: 8px;
    z-index: 1001;
}

.hamburger {
    display: block;
    width: 24px;
    height: 2px;
    background: var(--text-primary);
    position: relative;
    transition: all var(--transition);
}

.hamburger::before,
.hamburger::after {
    content: '';
    position: absolute;
    left: 0;
    width: 24px;
    height: 2px;
    background: var(--text-primary);
    transition: all var(--transition);
}

.hamburger::before { top: -7px; }
.hamburger::after { top: 7px; }

.nav-toggle.active .hamburger { background: transparent; }
.nav-toggle.active .hamburger::before { top: 0; transform: rotate(45deg); }
.nav-toggle.active .hamburger::after { top: 0; transform: rotate(-45deg); }

/* ==================== HERO ==================== */
.hero {
    min-height: 100vh;
    display: flex;
    align-items: center;
    justify-content: center;
    text-align: center;
    padding: 120px 24px 80px;
    position: relative;
    overflow: hidden;
}

.hero::before {
    content: '';
    position: absolute;
    top: -50%;
    left: -50%;
    width: 200%;
    height: 200%;
    background: radial-gradient(ellipse at center, rgba(79, 195, 247, 0.06) 0%, transparent 60%);
    pointer-events: none;
}

.hero-content {
    position: relative;
    z-index: 1;
}

.hero-icon {
    font-size: 4rem;
    color: var(--accent);
    margin-bottom: 24px;
    filter: drop-shadow(0 0 20px rgba(79, 195, 247, 0.3));
}

.hero-name {
    font-size: 2.8rem;
    font-weight: 700;
    margin-bottom: 12px;
    letter-spacing: -0.5px;
}

.hero-tagline {
    font-size: 1.15rem;
    color: var(--text-secondary);
    margin-bottom: 28px;
    font-weight: 400;
    max-width: 600px;
    margin-left: auto;
    margin-right: auto;
}

.hero-badges {
    display: flex;
    justify-content: center;
    flex-wrap: wrap;
    gap: 10px;
    margin-bottom: 32px;
}

.tag {
    background: rgba(79, 195, 247, 0.1);
    color: var(--accent);
    padding: 6px 16px;
    border-radius: 20px;
    font-size: 0.8rem;
    font-weight: 500;
}

/* ==================== ABOUT ==================== */
.about-content {
    max-width: 700px;
    margin: 0 auto;
    text-align: center;
}

.about-content p {
    font-size: 1.05rem;
    color: var(--text-secondary);
    line-height: 1.9;
    margin-bottom: 16px;
}

.about-content strong {
    color: var(--accent);
}

/* ==================== HOW IT WORKS ==================== */
.steps-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(220px, 1fr));
    gap: 24px;
}

.step-card {
    background: var(--bg-card);
    border: 1px solid var(--border);
    border-radius: var(--radius);
    padding: 28px;
    text-align: center;
    backdrop-filter: blur(10px);
    transition: all var(--transition);
}

.step-card:hover {
    background: var(--bg-card-hover);
    transform: translateY(-4px);
    box-shadow: 0 12px 40px rgba(0, 0, 0, 0.25);
}

.step-number {
    width: 44px;
    height: 44px;
    border-radius: 50%;
    background: var(--accent-gradient);
    color: #000;
    font-weight: 700;
    font-size: 1.2rem;
    display: flex;
    align-items: center;
    justify-content: center;
    margin: 0 auto 16px;
}

.step-card h3 {
    font-size: 1.05rem;
    margin-bottom: 8px;
}

.step-card p {
    font-size: 0.9rem;
    color: var(--text-secondary);
}

/* ==================== OUTCOMES GUIDE ==================== */
.subsection-title {
    font-size: 1.3rem;
    font-weight: 600;
    text-align: center;
    margin-top: 64px;
    margin-bottom: 32px;
    color: var(--text-primary);
}

.outcomes-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
    gap: 24px;
}

.outcome-card {
    background: var(--bg-card);
    border: 1px solid var(--border);
    border-radius: var(--radius);
    padding: 28px;
    backdrop-filter: blur(10px);
    transition: all var(--transition);
}

.outcome-card:hover {
    background: var(--bg-card-hover);
    transform: translateY(-2px);
    box-shadow: 0 8px 30px rgba(0, 0, 0, 0.2);
}

.outcome-icon {
    font-size: 1.8rem;
    margin-bottom: 12px;
}

.outcome-success .outcome-icon { color: var(--green); }
.outcome-diff .outcome-icon { color: var(--accent); }
.outcome-error .outcome-icon { color: var(--red); }

.outcome-card h4 {
    font-size: 1.05rem;
    font-weight: 600;
    margin-bottom: 8px;
}

.outcome-card p {
    font-size: 0.9rem;
    color: var(--text-secondary);
    line-height: 1.7;
    margin-bottom: 16px;
}

.outcome-example {
    background: rgba(255, 255, 255, 0.03);
    border: 1px solid var(--border);
    border-radius: 8px;
    padding: 14px 16px;
    font-size: 0.82rem;
    color: var(--text-secondary);
    line-height: 1.7;
}

.outcome-example-label {
    display: inline-block;
    background: var(--accent-gradient);
    color: #000;
    font-size: 0.7rem;
    font-weight: 700;
    padding: 2px 8px;
    border-radius: 4px;
    margin-bottom: 6px;
    text-transform: uppercase;
}

/* ==================== DEMO ==================== */
.demo-controls {
    background: var(--bg-card);
    border: 1px solid var(--border);
    border-radius: var(--radius);
    padding: 28px;
    margin-bottom: 24px;
}

.control-row {
    display: flex;
    align-items: flex-end;
    gap: 20px;
    flex-wrap: wrap;
}

.control-group {
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: 6px;
}

.control-group label {
    font-size: 0.85rem;
    font-weight: 500;
    color: var(--text-secondary);
}

.control-group input {
    background: var(--bg-secondary);
    border: 1px solid var(--border);
    border-radius: 8px;
    padding: 10px 14px;
    color: var(--text-primary);
    font-family: var(--font);
    font-size: 0.95rem;
    width: 140px;
    text-align: center;
    transition: border-color var(--transition);
}

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

.demo-tables {
    margin-bottom: 32px;
}

.table-section {
    background: var(--bg-card);
    border: 1px solid var(--border);
    border-radius: var(--radius);
    padding: 24px;
    margin-bottom: 16px;
}

.table-section h3 {
    font-size: 0.95rem;
    font-weight: 600;
    margin-bottom: 16px;
    color: var(--accent);
}

.table-wrapper {
    overflow-x: auto;
}

.table-wrapper table {
    width: 100%;
    border-collapse: collapse;
}

.table-wrapper th,
.table-wrapper td {
    padding: 8px 12px;
    text-align: center;
    font-size: 0.85rem;
}

.table-wrapper th {
    color: var(--text-secondary);
    font-weight: 500;
    border-bottom: 1px solid var(--border);
    white-space: nowrap;
}

.table-wrapper td input {
    background: var(--bg-secondary);
    border: 1px solid var(--border);
    border-radius: 6px;
    padding: 8px 10px;
    color: var(--text-primary);
    font-family: var(--font);
    font-size: 1rem;
    width: 100px;
    text-align: center;
    transition: border-color var(--transition);
    -webkit-appearance: none;
}

.table-wrapper td input:focus {
    outline: none;
    border-color: var(--accent);
}

.table-wrapper td label {
    color: var(--text-secondary);
    font-size: 0.8rem;
    font-weight: 500;
}

.demo-actions {
    display: flex;
    gap: 20px;
    justify-content: center;
    margin-top: 24px;
    flex-wrap: wrap;
}

.btn-group {
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: 8px;
    max-width: 220px;
}

.btn-desc {
    font-size: 0.75rem;
    color: var(--text-secondary);
    text-align: center;
    line-height: 1.5;
}

.control-row .btn-group {
    flex-direction: row;
    align-items: center;
    max-width: none;
    gap: 16px;
}

.control-row .btn-group .btn-desc {
    text-align: left;
}

/* Placeholder-style inputs */
.table-wrapper td input.placeholder-mode {
    color: var(--text-secondary);
}

.table-wrapper td input.placeholder-mode:focus {
    color: var(--text-primary);
}

/* ==================== RESULTS ==================== */
.results-container {
    margin-top: 40px;
}

.results-grid {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 24px;
    margin-bottom: 24px;
}

.result-card {
    background: var(--bg-card);
    border: 1px solid var(--border);
    border-radius: var(--radius);
    overflow: hidden;
    transition: all var(--transition);
}

.result-card:hover {
    background: var(--bg-card-hover);
}

.result-header {
    display: flex;
    align-items: center;
    justify-content: space-between;
    padding: 20px 24px;
    border-bottom: 1px solid var(--border);
}

.result-header h3 {
    font-size: 1.1rem;
    font-weight: 600;
}

.result-header h3 i {
    margin-right: 8px;
    color: var(--accent);
}

.complexity-badge {
    background: rgba(79, 195, 247, 0.1);
    color: var(--accent);
    padding: 4px 12px;
    border-radius: 20px;
    font-size: 0.75rem;
    font-weight: 600;
}

.result-body {
    padding: 24px;
    overflow-x: auto;
    -webkit-overflow-scrolling: touch;
}

.result-body table {
    width: 100%;
    min-width: 400px;
    border-collapse: collapse;
    margin-bottom: 16px;
}

.result-body th,
.result-body td {
    padding: 8px 10px;
    text-align: center;
    font-size: 0.82rem;
}

.result-body th {
    color: var(--text-secondary);
    font-weight: 500;
    border-bottom: 1px solid var(--border);
}

.result-body td {
    color: var(--text-primary);
}

.result-total {
    font-size: 1.3rem;
    font-weight: 700;
    text-align: center;
    padding-top: 8px;
    border-top: 1px solid var(--border);
}

.result-total span {
    color: var(--accent);
}

.result-skipped {
    text-align: center;
    color: var(--text-secondary);
    padding: 40px 0;
    font-size: 0.95rem;
}

.result-skipped i {
    display: block;
    font-size: 2rem;
    color: var(--text-secondary);
    margin-bottom: 12px;
    opacity: 0.5;
}

.result-error {
    text-align: center;
    color: var(--red);
    padding: 40px 0;
    font-size: 0.95rem;
}

/* Comparison Bar */
.comparison-bar {
    background: var(--bg-card);
    border: 1px solid var(--border);
    border-radius: var(--radius);
    padding: 24px;
    text-align: center;
}

.comparison-bar .match {
    color: var(--green);
    font-weight: 600;
    font-size: 1rem;
}

.comparison-bar .match i {
    margin-right: 6px;
}

.comparison-bar .diff {
    color: var(--accent);
    font-weight: 600;
    font-size: 1rem;
}

.comparison-bar .diff i {
    margin-right: 6px;
}

.comparison-bar .detail {
    color: var(--text-secondary);
    font-size: 0.85rem;
    margin-top: 6px;
}

/* ==================== ALGORITHMS ==================== */
.algo-grid {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 24px;
}

.algo-card {
    background: var(--bg-card);
    border: 1px solid var(--border);
    border-radius: var(--radius);
    padding: 28px;
    backdrop-filter: blur(10px);
    transition: all var(--transition);
}

.algo-card:hover {
    background: var(--bg-card-hover);
    transform: translateY(-4px);
    box-shadow: 0 12px 40px rgba(0, 0, 0, 0.25);
}

.algo-card h3 {
    font-size: 1.15rem;
    margin-bottom: 8px;
}

.algo-card h3 i {
    margin-right: 8px;
    color: var(--accent);
}

.algo-complexity {
    color: var(--accent);
    font-size: 0.85rem;
    font-weight: 500;
    margin-bottom: 16px;
}

.algo-card ul {
    padding-left: 18px;
}

.algo-card li {
    color: var(--text-secondary);
    font-size: 0.9rem;
    margin-bottom: 8px;
    list-style: disc;
}

/* ==================== TEAM ==================== */
.team-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(240px, 1fr));
    gap: 24px;
    max-width: 800px;
    margin: 0 auto;
}

.team-card {
    background: var(--bg-card);
    border: 1px solid var(--border);
    border-radius: var(--radius);
    padding: 28px;
    text-align: center;
    backdrop-filter: blur(10px);
    transition: all var(--transition);
}

.team-card:hover {
    background: var(--bg-card-hover);
    transform: translateY(-2px);
    box-shadow: 0 8px 30px rgba(0, 0, 0, 0.2);
}

.team-card h3 {
    font-size: 1.05rem;
    font-weight: 600;
    margin-bottom: 4px;
}

.team-card p {
    color: var(--text-secondary);
    font-size: 0.85rem;
}

/* ==================== FOOTER ==================== */
.footer {
    padding: 40px 0;
    text-align: center;
    border-top: 1px solid var(--border);
}

.footer-social {
    display: flex;
    justify-content: center;
    gap: 20px;
    margin-bottom: 16px;
}

.footer-social a {
    color: var(--text-secondary);
    font-size: 1.2rem;
    transition: all var(--transition);
}

.footer-social a:hover {
    color: var(--accent);
    transform: translateY(-2px);
}

.footer-copy {
    color: var(--text-secondary);
    font-size: 0.85rem;
}

/* ==================== RESPONSIVE ==================== */
@media (max-width: 768px) {
    .nav-toggle {
        display: block;
    }

    .nav-links {
        position: fixed;
        top: 0;
        right: -100%;
        left: auto;
        transform: none;
        width: 200px;
        height: 100vh;
        background: rgba(10, 10, 15, 0.98);
        backdrop-filter: blur(20px);
        flex-direction: column;
        justify-content: center;
        align-items: center;
        gap: 28px;
        transition: right var(--transition);
    }

    .nav-links.open {
        right: 0;
    }

    .nav-links a {
        font-size: 1.1rem;
    }

    .hero-name {
        font-size: 2rem;
    }

    .hero-tagline {
        font-size: 1rem;
    }

    .section {
        padding: 70px 0;
    }

    .section-title {
        font-size: 1.6rem;
        margin-bottom: 36px;
    }

    .results-grid {
        grid-template-columns: 1fr;
    }

    .algo-grid {
        grid-template-columns: 1fr;
    }

    .control-row {
        flex-direction: column;
        align-items: stretch;
    }

    .control-group input {
        width: 100%;
    }

    .steps-grid {
        grid-template-columns: 1fr 1fr;
    }

    .outcomes-grid {
        grid-template-columns: 1fr;
    }

    .btn-group {
        max-width: 100%;
    }

    .control-row .btn-group {
        flex-direction: column;
        align-items: stretch;
    }

    .control-row .btn-group .btn-desc {
        text-align: center;
    }
}

@media (max-width: 480px) {
    .hero-name {
        font-size: 1.6rem;
    }

    .steps-grid {
        grid-template-columns: 1fr;
    }

    .team-grid {
        grid-template-columns: 1fr;
    }
}