/* ==========================================
   Variables & Reset
   ========================================== */
:root {
    --primary-color: #2563eb;
    --primary-dark: #1e40af;
    --primary-light: #3b82f6;
    --secondary-color: #7c3aed;
    --accent-color: #f97316;
    --dark-bg: #0f172a;
    --light-bg: #f8fafc;
    --card-bg: #ffffff;
    --text-dark: #1e293b;
    --text-muted: #64748b;
    --border-color: #e2e8f0;
    --shadow: 0 10px 30px rgba(0, 0, 0, 0.1);
    --shadow-hover: 0 15px 40px rgba(0, 0, 0, 0.15);
}

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

html {
    scroll-behavior: smooth;
}

body {
    font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
    line-height: 1.6;
    color: var(--text-dark);
    background-color: #ffffff;
}

/* ==========================================
   Layout
   ========================================== */
.container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 20px;
}

/* ==========================================
   Header & Navigation
   ========================================== */
.header {
    background: linear-gradient(135deg, var(--dark-bg) 0%, #1a2f5a 100%);
    color: white;
    padding: 1rem 0;
    position: sticky;
    top: 0;
    z-index: 100;
    box-shadow: var(--shadow);
}

.navbar {
    width: 100%;
}

.nav-content {
    display: flex;
    justify-content: space-between;
    align-items: center;
}

.logo {
    display: flex;
    align-items: center;
    gap: 10px;
}

.logo-text {
    font-size: 1.8rem;
    font-weight: 700;
    background: linear-gradient(135deg, var(--primary-light) 0%, var(--secondary-color) 100%);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
}

.nav-menu {
    display: flex;
    list-style: none;
    gap: 2rem;
}

.nav-menu a {
    color: white;
    text-decoration: none;
    font-weight: 500;
    transition: color 0.3s ease;
    position: relative;
}

.nav-menu a:hover {
    color: var(--primary-light);
}

.nav-menu a::after {
    content: '';
    position: absolute;
    bottom: -5px;
    left: 0;
    width: 0;
    height: 2px;
    background: var(--primary-light);
    transition: width 0.3s ease;
}

.nav-menu a:hover::after {
    width: 100%;
}

/* ==========================================
   Hero Section
   ========================================== */
.hero {
    position: relative;
    overflow: hidden;
    background:
        radial-gradient(circle at 12% 18%, rgba(59, 130, 246, 0.22), transparent 28%),
        radial-gradient(circle at 82% 16%, rgba(124, 58, 237, 0.18), transparent 30%),
        linear-gradient(135deg, #f8fafc 0%, #eef2ff 48%, #f8fafc 100%);
    padding: 72px 0 88px;
    isolation: isolate;
}

.hero::before {
    content: '';
    position: absolute;
    inset: 0;
    background-image:
        linear-gradient(rgba(15, 23, 42, 0.035) 1px, transparent 1px),
        linear-gradient(90deg, rgba(15, 23, 42, 0.035) 1px, transparent 1px);
    background-size: 44px 44px;
    mask-image: linear-gradient(to bottom, black, transparent 86%);
    z-index: -2;
}

.hero::after {
    content: '';
    position: absolute;
    width: 520px;
    height: 520px;
    right: -180px;
    bottom: -220px;
    background: linear-gradient(135deg, rgba(37, 99, 235, 0.22), rgba(249, 115, 22, 0.12));
    border-radius: 999px;
    filter: blur(10px);
    z-index: -1;
}

.hero-layout {
    display: grid;
    grid-template-columns: minmax(0, 1.08fr) minmax(320px, 0.72fr);
    gap: clamp(3rem, 6vw, 6rem);
    align-items: start;
}

.hero-content {
    max-width: 780px;
}

.hero-eyebrow {
    display: inline-flex;
    align-items: center;
    gap: 0.55rem;
    margin-bottom: 1.35rem;
    padding: 0.55rem 0.85rem;
    border: 1px solid rgba(37, 99, 235, 0.18);
    border-radius: 999px;
    background: rgba(255, 255, 255, 0.72);
    color: var(--primary-dark);
    box-shadow: 0 10px 30px rgba(37, 99, 235, 0.08);
    font-size: 0.82rem;
    font-weight: 800;
    letter-spacing: 0.08em;
    text-transform: uppercase;
}

.hero-title {
    max-width: 860px;
    font-size: 4.8rem;
    font-weight: 900;
    line-height: 1.02;
    letter-spacing: 0;
    padding-bottom: 0.08em;
    margin-bottom: 1.5rem;
    color: var(--dark-bg);
    background: linear-gradient(135deg, #0f172a 0%, var(--primary-dark) 48%, var(--secondary-color) 100%);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
}

.hero-subtitle {
    max-width: 700px;
    font-size: 1.42rem;
    color: #334155;
    margin-bottom: 1.2rem;
    line-height: 1.45;
    font-weight: 650;
}

.hero-description {
    max-width: 720px;
    font-size: 1.05rem;
    color: var(--text-muted);
    margin-bottom: 1.9rem;
    line-height: 1.85;
}

.hero-points {
    display: flex;
    flex-wrap: wrap;
    gap: 0.75rem;
    margin-bottom: 0;
}

.hero-points span {
    display: inline-flex;
    align-items: center;
    min-height: 40px;
    padding: 0.62rem 0.9rem;
    border: 1px solid rgba(37, 99, 235, 0.14);
    border-radius: 999px;
    background: rgba(255, 255, 255, 0.8);
    color: #1e293b;
    box-shadow: 0 12px 28px rgba(15, 23, 42, 0.07);
    font-size: 0.94rem;
    font-weight: 700;
}

.hero-actions {
    display: flex;
    flex-wrap: wrap;
    gap: 1rem;
    align-items: center;
    max-width: 560px;
    margin-top: 2.2rem;
    padding-top: 1.8rem;
    border-top: 1px solid rgba(37, 99, 235, 0.16);
}

.hero-video-wrap .hero-actions {
    justify-content: center;
    max-width: 100%;
    margin-top: 1.2rem;
    padding-top: 0;
    border-top: 0;
}

.cta-button {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    min-height: 54px;
    background: linear-gradient(135deg, var(--primary-color) 0%, var(--primary-light) 100%);
    color: white;
    padding: 15px 28px;
    border-radius: 999px;
    text-decoration: none;
    font-weight: 800;
    font-size: 1rem;
    letter-spacing: -0.01em;
    transition: transform 0.3s ease, box-shadow 0.3s ease, background 0.3s ease, border-color 0.3s ease;
    border: 2px solid var(--primary-color);
    cursor: pointer;
    box-shadow: 0 14px 35px rgba(37, 99, 235, 0.22);
}

.cta-button:hover {
    transform: translateY(-3px);
    box-shadow: 0 18px 42px rgba(37, 99, 235, 0.32);
}

.cta-button.primary {
    background: linear-gradient(135deg, var(--dark-bg) 0%, var(--primary-dark) 54%, var(--secondary-color) 100%);
    border-color: rgba(15, 23, 42, 0.9);
}

.cta-button.secondary {
    background: rgba(255, 255, 255, 0.72);
    color: var(--dark-bg);
    border-color: rgba(15, 23, 42, 0.16);
    box-shadow: 0 14px 35px rgba(15, 23, 42, 0.08);
    backdrop-filter: blur(12px);
}

.cta-button.secondary:hover {
    border-color: rgba(37, 99, 235, 0.4);
    background: rgba(255, 255, 255, 0.95);
    box-shadow: 0 18px 42px rgba(15, 23, 42, 0.14);
}

.hero-video-wrap {
    align-self: start;
    justify-self: center;
    width: min(100%, 410px);
    margin-top: 40px;
}

.hero-video-card {
    position: relative;
    padding: 14px;
    border: 1px solid rgba(255, 255, 255, 0.72);
    border-radius: 34px;
    background: linear-gradient(145deg, rgba(255, 255, 255, 0.78), rgba(255, 255, 255, 0.36));
    box-shadow:
        0 34px 80px rgba(15, 23, 42, 0.2),
        inset 0 1px 0 rgba(255, 255, 255, 0.8);
    backdrop-filter: blur(18px);
}

.hero-video-card.is-floating {
    position: fixed;
    right: 22px;
    bottom: 92px;
    z-index: 200;
    width: 220px;
    padding: 8px;
    border-radius: 22px;
    box-shadow:
        0 24px 70px rgba(15, 23, 42, 0.34),
        inset 0 1px 0 rgba(255, 255, 255, 0.72);
}

.hero-video-card::before {
    content: '';
    position: absolute;
    inset: -1px;
    border-radius: inherit;
    padding: 1px;
    background: linear-gradient(135deg, rgba(59, 130, 246, 0.65), rgba(124, 58, 237, 0.35), rgba(249, 115, 22, 0.32));
    -webkit-mask: linear-gradient(#fff 0 0) content-box, linear-gradient(#fff 0 0);
    -webkit-mask-composite: xor;
    mask-composite: exclude;
    pointer-events: none;
}

.hero-video-card::after {
    content: 'Intro video';
    position: absolute;
    top: 30px;
    left: 30px;
    z-index: 2;
    padding: 0.38rem 0.7rem;
    border-radius: 999px;
    background: rgba(15, 23, 42, 0.72);
    color: white;
    font-size: 0.75rem;
    font-weight: 800;
    letter-spacing: 0.04em;
    backdrop-filter: blur(10px);
}

.hero-video-card.is-floating::after {
    top: 16px;
    left: 16px;
    padding: 0.28rem 0.52rem;
    font-size: 0.64rem;
}

.hero-video {
    display: block;
    width: 100%;
    aspect-ratio: 9 / 16;
    max-height: 680px;
    object-fit: cover;
    border-radius: 24px;
    background: linear-gradient(160deg, #0f172a, #1e293b);
    box-shadow: inset 0 0 0 1px rgba(255, 255, 255, 0.14);
}

.hero-video-card.is-floating .hero-video {
    max-height: none;
    border-radius: 16px;
}

.floating-video-close {
    display: none;
    position: absolute;
    top: 12px;
    right: 12px;
    z-index: 4;
    align-items: center;
    justify-content: center;
    width: 28px;
    height: 28px;
    border: 1px solid rgba(255, 255, 255, 0.38);
    border-radius: 999px;
    background: rgba(15, 23, 42, 0.78);
    color: white;
    font-size: 1.2rem;
    line-height: 1;
    cursor: pointer;
    backdrop-filter: blur(10px);
    transition: transform 0.2s ease, background 0.2s ease;
}

.hero-video-card.is-floating .floating-video-close {
    display: inline-flex;
}

.floating-video-close:hover {
    transform: scale(1.06);
    background: rgba(249, 115, 22, 0.92);
}

.video-caption {
    max-width: 340px;
    margin: 1rem auto 0;
    color: var(--text-muted);
    font-size: 0.92rem;
    line-height: 1.65;
    text-align: center;
}

/* ==========================================
   Services Section
   ========================================== */
.services {
    padding: 96px 0;
    background:
        linear-gradient(180deg, #ffffff 0%, var(--light-bg) 42%, #eef2ff 100%);
}

.section-title {
    font-size: 2.5rem;
    font-weight: 800;
    text-align: center;
    margin-bottom: 3rem;
    color: var(--dark-bg);
    position: relative;
    padding-bottom: 1rem;
}

.section-title::after {
    content: '';
    position: absolute;
    bottom: 0;
    left: 50%;
    transform: translateX(-50%);
    width: 80px;
    height: 4px;
    background: linear-gradient(90deg, var(--primary-color), var(--secondary-color));
    border-radius: 2px;
}

.services-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(320px, 1fr));
    gap: 1.35rem;
    align-items: stretch;
}

.service-card {
    display: flex;
    flex-direction: column;
    min-height: 280px;
    background:
        linear-gradient(180deg, rgba(255, 255, 255, 0.98) 0%, rgba(248, 250, 252, 0.96) 100%);
    padding: 2.15rem;
    border-radius: 14px;
    box-shadow: 0 18px 45px rgba(15, 23, 42, 0.08);
    transition: all 0.3s ease;
    border: 1px solid rgba(148, 163, 184, 0.28);
    position: relative;
    overflow: hidden;
}

.service-card::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    height: 3px;
    background: linear-gradient(90deg, var(--primary-color), rgba(59, 130, 246, 0.25));
}

.service-card.premium::before {
    background: linear-gradient(90deg, var(--secondary-color), var(--primary-light), var(--accent-color));
}

.service-card:hover {
    transform: translateY(-6px);
    border-color: rgba(37, 99, 235, 0.24);
    box-shadow: 0 24px 60px rgba(15, 23, 42, 0.13);
}

.service-header {
    display: flex;
    justify-content: space-between;
    align-items: flex-start;
    gap: 1rem;
    margin-bottom: 1.25rem;
}

.service-header h3 {
    font-size: 1.28rem;
    color: var(--dark-bg);
    flex: 1;
    line-height: 1.25;
    letter-spacing: 0;
}

.badge {
    background: rgba(37, 99, 235, 0.08);
    color: var(--primary-dark);
    padding: 0.42rem 0.65rem;
    border: 1px solid rgba(37, 99, 235, 0.16);
    border-radius: 999px;
    font-size: 0.68rem;
    font-weight: 800;
    letter-spacing: 0.08em;
    text-transform: uppercase;
    white-space: nowrap;
}

.service-card.premium .badge {
    background: rgba(124, 58, 237, 0.08);
    border-color: rgba(124, 58, 237, 0.18);
    color: var(--secondary-color);
}

.service-description {
    color: #475569;
    margin-bottom: 2rem;
    line-height: 1.75;
    font-size: 0.98rem;
}

.service-price {
    margin-top: auto;
    padding-top: 1.1rem;
    border-top: 1px solid rgba(148, 163, 184, 0.24);
    font-size: 0.98rem;
    font-weight: 800;
    color: var(--primary-dark);
    letter-spacing: 0;
}

.service-card.premium .service-price {
    color: var(--secondary-color);
}

.services-intro {
    max-width: 760px;
    margin: -1.6rem auto 3.4rem;
    text-align: center;
    color: #475569;
    font-size: 1.12rem;
    line-height: 1.8;
}

.services-note {
    width: fit-content;
    max-width: 100%;
    margin: 2.4rem auto 0;
    padding: 0.72rem 1.05rem;
    border: 1px solid rgba(37, 99, 235, 0.18);
    border-radius: 999px;
    background: rgba(255, 255, 255, 0.72);
    color: var(--primary-dark);
    box-shadow: 0 14px 35px rgba(15, 23, 42, 0.07);
    font-size: 0.9rem;
    font-weight: 800;
    letter-spacing: 0.04em;
    text-transform: uppercase;
    text-align: center;
}

/* ==========================================
   Expertise Section
   ========================================== */
.expertise {
    padding: 80px 0;
    background: var(--card-bg);
}

.expertise-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
    gap: 2rem;
}

.expertise-item {
    text-align: center;
    padding: 2rem;
    border-radius: 12px;
    background: var(--light-bg);
    transition: all 0.3s ease;
    border: 2px solid var(--border-color);
}

.expertise-item:hover {
    border-color: var(--primary-color);
    transform: translateY(-4px);
    box-shadow: var(--shadow);
}

.expertise-icon {
    font-size: 3rem;
    margin-bottom: 1rem;
}

.expertise-item h3 {
    font-size: 1.2rem;
    margin-bottom: 0.5rem;
    color: var(--dark-bg);
}

.expertise-item p {
    color: var(--text-muted);
    font-size: 0.95rem;
    line-height: 1.6;
}

/* ==========================================
   Background Section
   ========================================== */
.background {
    padding: 80px 0;
    background: linear-gradient(135deg, var(--dark-bg) 0%, #1a2f5a 100%);
}

.background .section-title {
    color: white;
}

.background .section-title::after {
    background: linear-gradient(90deg, var(--primary-light), var(--accent-color));
}

.background-content {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(240px, 1fr));
    gap: 2rem;
}

.background-card {
    background: rgba(255, 255, 255, 0.1);
    padding: 2rem;
    border-radius: 12px;
    border: 2px solid rgba(255, 255, 255, 0.2);
    color: white;
    backdrop-filter: blur(10px);
    transition: all 0.3s ease;
}

.background-card:hover {
    background: rgba(255, 255, 255, 0.15);
    border-color: var(--primary-light);
    transform: translateY(-4px);
}

.background-card.video-sync-highlight {
    background: rgba(255, 255, 255, 0.2);
    border-color: var(--accent-color);
    box-shadow: 0 0 0 4px rgba(249, 115, 22, 0.18), 0 22px 52px rgba(0, 0, 0, 0.2);
    transform: translateY(-4px) !important;
    animation: videoTopicPulse 0.8s ease-in-out infinite alternate;
}

.background-card h3 {
    font-size: 1.3rem;
    margin-bottom: 1rem;
    color: var(--primary-light);
}

.background-card p {
    color: rgba(255, 255, 255, 0.8);
    line-height: 1.6;
}

/* ==========================================
   CTA Section
   ========================================== */
.cta-section {
    padding: 80px 0;
    background: linear-gradient(135deg, var(--primary-color) 0%, var(--primary-dark) 100%);
    text-align: center;
    color: white;
}

.cta-section h2 {
    font-size: 2.5rem;
    font-weight: 800;
    margin-bottom: 1rem;
}

.cta-section p {
    font-size: 1.2rem;
    margin-bottom: 2rem;
    opacity: 0.9;
}

.scroll-top-button {
    display: none;
    position: fixed;
    right: 22px;
    bottom: 22px;
    z-index: 210;
    align-items: center;
    justify-content: center;
    width: 52px;
    height: 52px;
    border: 1px solid rgba(255, 255, 255, 0.28);
    border-radius: 999px;
    background: linear-gradient(135deg, var(--dark-bg), var(--primary-dark));
    color: white;
    font-size: 1.35rem;
    font-weight: 900;
    cursor: pointer;
    box-shadow: 0 18px 42px rgba(15, 23, 42, 0.24);
    transition: transform 0.2s ease, box-shadow 0.2s ease;
}

.scroll-top-button:hover {
    transform: translateY(-2px);
    box-shadow: 0 22px 52px rgba(15, 23, 42, 0.32);
}

/* ==========================================
   Footer
   ========================================== */
.footer {
    background: var(--dark-bg);
    color: white;
    padding: 60px 0 20px;
}

.footer-content {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
    gap: 2rem;
    margin-bottom: 2rem;
}

.footer-section h3 {
    font-size: 1.2rem;
    margin-bottom: 1rem;
    color: var(--primary-light);
}

.footer-section p {
    color: rgba(255, 255, 255, 0.7);
    margin-bottom: 0.5rem;
    line-height: 1.8;
}

.footer-section a {
    color: var(--primary-light);
    text-decoration: none;
    transition: color 0.3s ease;
}

.footer-section a:hover {
    color: var(--secondary-color);
}

.social-links {
    display: flex;
    gap: 1rem;
}

.social-link {
    display: inline-block;
    padding: 8px 16px;
    border: 2px solid var(--primary-light);
    border-radius: 20px;
    transition: all 0.3s ease;
}

.social-link:hover {
    background: var(--primary-light);
    color: white;
}

.contact-form-section {
    min-width: min(100%, 320px);
}

.contact-form {
    display: grid;
    gap: 0.75rem;
}

.contact-form label {
    color: rgba(255, 255, 255, 0.78);
    font-size: 0.86rem;
    font-weight: 700;
}

.contact-form input,
.contact-form textarea {
    width: 100%;
    border: 1px solid rgba(255, 255, 255, 0.18);
    border-radius: 10px;
    background: rgba(255, 255, 255, 0.08);
    color: white;
    padding: 0.8rem 0.9rem;
    font: inherit;
    outline: none;
    transition: border-color 0.3s ease, background 0.3s ease, box-shadow 0.3s ease;
}

.contact-form textarea {
    resize: vertical;
    min-height: 130px;
}

.contact-form input::placeholder,
.contact-form textarea::placeholder {
    color: rgba(255, 255, 255, 0.42);
}

.contact-form input:focus,
.contact-form textarea:focus {
    border-color: var(--primary-light);
    background: rgba(255, 255, 255, 0.12);
    box-shadow: 0 0 0 3px rgba(59, 130, 246, 0.18);
}

.contact-submit {
    justify-self: start;
    margin-top: 0.25rem;
    padding: 0.78rem 1.05rem;
    border: 1px solid var(--primary-light);
    border-radius: 999px;
    background: var(--primary-light);
    color: white;
    font: inherit;
    font-weight: 800;
    cursor: pointer;
    transition: transform 0.3s ease, box-shadow 0.3s ease, background 0.3s ease;
}

.contact-submit:hover {
    transform: translateY(-2px);
    background: var(--primary-color);
    box-shadow: 0 12px 28px rgba(37, 99, 235, 0.28);
}

.contact-form-note {
    margin-top: 0.8rem;
    font-size: 0.82rem;
}

.footer-bottom {
    text-align: center;
    padding-top: 2rem;
    border-top: 2px solid rgba(255, 255, 255, 0.1);
    color: rgba(255, 255, 255, 0.6);
    font-size: 0.9rem;
}

/* ==========================================
   Systems, Automation & AI Integration Section
   ========================================== */
.ai-applications {
    padding: 80px 0;
    background: linear-gradient(135deg, #f0f9ff 0%, #f5e6ff 100%);
}

.section-subtitle {
    text-align: center;
    font-size: 1.1rem;
    color: var(--text-muted);
    margin-bottom: 3rem;
    max-width: 700px;
    margin-left: auto;
    margin-right: auto;
    line-height: 1.8;
}

.ai-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
    gap: 2rem;
    margin-bottom: 4rem;
}

.ai-card {
    background: var(--card-bg);
    padding: 2.5rem;
    border-radius: 12px;
    box-shadow: var(--shadow);
    border-left: 4px solid var(--primary-color);
    transition: all 0.3s ease;
}

.ai-card:hover {
    transform: translateY(-8px);
    box-shadow: var(--shadow-hover);
    border-left-color: var(--secondary-color);
}

.ai-icon {
    font-size: 2.5rem;
    margin-bottom: 1rem;
}

.ai-card h3 {
    font-size: 1.3rem;
    color: var(--dark-bg);
    margin-bottom: 1.5rem;
}

.ai-list {
    list-style: none;
}

.ai-list li {
    padding: 0.6rem 0 0.6rem 1.5rem;
    color: var(--text-dark);
    position: relative;
    font-size: 0.95rem;
    line-height: 1.6;
}

.ai-list li::before {
    content: '✓';
    position: absolute;
    left: 0;
    color: var(--primary-color);
    font-weight: bold;
}

/* Tech Deep Dive Section */
.tech-deep-dive {
    background: linear-gradient(135deg, rgba(37, 99, 235, 0.1) 0%, rgba(124, 58, 237, 0.1) 100%);
    padding: 3rem;
    border-radius: 16px;
    border: 2px solid var(--border-color);
    margin-top: 3rem;
}

.tech-deep-dive h3 {
    font-size: 1.8rem;
    color: var(--dark-bg);
    margin-bottom: 2rem;
    text-align: center;
}

.tech-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
    gap: 2rem;
}

.tech-item {
    background: var(--card-bg);
    padding: 2rem;
    border-radius: 12px;
    border: 2px solid var(--border-color);
    transition: all 0.3s ease;
}

.tech-item:hover {
    border-color: var(--primary-color);
    box-shadow: var(--shadow);
}

.tech-item h4 {
    font-size: 1.1rem;
    color: var(--primary-color);
    margin-bottom: 0.8rem;
}

.tech-item p {
    color: var(--text-muted);
    font-size: 0.9rem;
    line-height: 1.6;
}

/* ==========================================
   Engineering Principles Section
   ========================================== */
.principles {
    padding: 80px 0;
    background: #ffffff;
}

.principles-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(260px, 1fr));
    gap: 1.35rem;
}

.principle-card {
    min-height: 180px;
    padding: 2rem;
    border-radius: 12px;
    background: var(--light-bg);
    border: 1px solid rgba(148, 163, 184, 0.32);
    box-shadow: 0 14px 35px rgba(15, 23, 42, 0.06);
    transition: transform 0.3s ease, border-color 0.3s ease, box-shadow 0.3s ease;
}

.principle-card:hover {
    transform: translateY(-4px);
    border-color: rgba(37, 99, 235, 0.28);
    box-shadow: 0 20px 46px rgba(15, 23, 42, 0.1);
}

.principle-card.video-sync-highlight {
    border-color: var(--accent-color);
    background: #fff7ed;
    box-shadow: 0 0 0 4px rgba(249, 115, 22, 0.16), 0 22px 52px rgba(15, 23, 42, 0.13);
    transform: translateY(-6px) !important;
    animation: videoTopicPulse 0.8s ease-in-out infinite alternate;
}

.video-sync-cta.video-sync-highlight {
    box-shadow: 0 0 0 6px rgba(249, 115, 22, 0.24), 0 22px 52px rgba(37, 99, 235, 0.35);
    transform: translateY(-3px) scale(1.03) !important;
    animation: videoCtaPulse 0.75s ease-in-out infinite alternate;
}

.video-sync-paused .video-sync-highlight {
    animation-play-state: paused;
}

@keyframes videoTopicPulse {
    from {
        filter: brightness(1);
        box-shadow: 0 0 0 4px rgba(249, 115, 22, 0.18), 0 22px 52px rgba(15, 23, 42, 0.13);
    }
    to {
        filter: brightness(1.12);
        box-shadow: 0 0 0 9px rgba(249, 115, 22, 0.38), 0 26px 60px rgba(249, 115, 22, 0.26);
    }
}

@keyframes videoCtaPulse {
    from {
        filter: brightness(1);
        box-shadow: 0 0 0 6px rgba(249, 115, 22, 0.24), 0 22px 52px rgba(37, 99, 235, 0.35);
    }
    to {
        filter: brightness(1.18);
        box-shadow: 0 0 0 12px rgba(249, 115, 22, 0.42), 0 26px 62px rgba(249, 115, 22, 0.32);
    }
}

.principle-card h3 {
    color: var(--dark-bg);
    font-size: 1.2rem;
    margin-bottom: 0.75rem;
}

.success-letter {
    color: var(--accent-color);
    font-size: 1.45em;
    font-weight: 900;
    line-height: 0;
    text-shadow: 0 0 18px rgba(249, 115, 22, 0.35);
}

.principle-card p {
    color: var(--text-muted);
    line-height: 1.65;
    font-size: 0.96rem;
}

/* ==========================================
   Responsive Design
   ========================================== */
@media (max-width: 768px) {
    .container {
        padding: 0 16px;
    }

    .header {
        position: static;
        padding: 0.85rem 0;
    }

    .nav-content {
        flex-direction: column;
        gap: 0.8rem;
        align-items: stretch;
    }

    .logo {
        justify-content: center;
    }

    .nav-menu {
        flex-wrap: wrap;
        justify-content: center;
        gap: 0.7rem 1rem;
        font-size: 0.88rem;
    }

    .hero-layout {
        grid-template-columns: 1fr;
        gap: 2.25rem;
    }

    .hero-content {
        max-width: 100%;
    }

    .hero-eyebrow {
        font-size: 0.74rem;
        line-height: 1.4;
    }

    .hero-title {
        font-size: 2.55rem;
        letter-spacing: 0;
        line-height: 1.02;
    }

    .hero-subtitle {
        font-size: 1.2rem;
    }

    .hero-actions {
        align-items: stretch;
    }

    .hero-video-wrap {
        width: min(100%, 340px);
        margin-top: 0;
    }

    .section-title {
        font-size: 1.9rem;
    }

    .hero {
        padding: 34px 0 48px;
    }

    .services,
    .expertise,
    .background,
    .ai-applications,
    .principles,
    .cta-section {
        padding: 48px 0;
    }

    .services-grid,
    .expertise-grid,
    .background-content,
    .ai-grid,
    .principles-grid,
    .tech-grid {
        grid-template-columns: 1fr;
    }

    .cta-section h2 {
        font-size: 2rem;
    }

    .service-header {
        flex-direction: column;
    }

    .badge {
        margin-left: 0;
        margin-top: 0.5rem;
    }

    .services-intro {
        margin-top: -1.2rem;
        margin-bottom: 2.6rem;
        font-size: 1rem;
    }
}

@media (max-width: 480px) {
    .hero {
        padding: 32px 0 48px;
    }

    .hero-eyebrow {
        border-radius: 18px;
    }

    .hero-title {
        font-size: 2.35rem;
    }

    .hero-subtitle {
        font-size: 1.08rem;
    }

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

    .hero-actions,
    .hero-actions .cta-button {
        width: 100%;
    }

    .hero-points span {
        width: 100%;
        justify-content: center;
    }

    .hero-video-card {
        padding: 10px;
        border-radius: 28px;
    }

    .hero-video-card.is-floating {
        left: 50%;
        right: auto;
        bottom: 78px;
        width: min(190px, calc(100vw - 32px));
        padding: 7px;
        border-radius: 20px;
        transform: translateX(-50%);
    }

    .hero-video {
        border-radius: 20px;
    }

    .hero-video-card::after {
        top: 22px;
        left: 22px;
    }

    .section-title {
        font-size: 1.5rem;
    }

    .nav-menu {
        gap: 0.5rem;
        font-size: 0.8rem;
    }

    .logo-text {
        font-size: 1.4rem;
    }

    .cta-button {
        padding: 12px 30px;
        font-size: 1rem;
    }

    .service-card {
        min-height: auto;
        padding: 1.6rem;
    }

    .services-note {
        border-radius: 18px;
        font-size: 0.78rem;
        line-height: 1.5;
    }

    .footer-content {
        grid-template-columns: 1fr;
    }
}

/* ==========================================
   Animations
   ========================================== */
@keyframes fadeIn {
    from {
        opacity: 0;
        transform: translateY(20px);
    }
    to {
        opacity: 1;
        transform: translateY(0);
    }
}

.service-card,
.expertise-item,
.background-card,
.ai-card,
.principle-card,
.tech-item {
    animation: fadeIn 0.6s ease forwards;
}

.service-card:nth-child(1) { animation-delay: 0.1s; }
.service-card:nth-child(2) { animation-delay: 0.2s; }
.service-card:nth-child(3) { animation-delay: 0.3s; }
.service-card:nth-child(4) { animation-delay: 0.4s; }
.service-card:nth-child(5) { animation-delay: 0.5s; }
.service-card:nth-child(6) { animation-delay: 0.6s; }
.service-card:nth-child(7) { animation-delay: 0.7s; }
.service-card:nth-child(8) { animation-delay: 0.8s; }