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

:root {
    --blue-900: #0a1628;
    --blue-800: #1a2a4a;
    --blue-600: #2563eb;
    --blue-500: #3b82f6;
    --blue-400: #60a5fa;
    --blue-100: #dbeafe;
    --blue-50: #eff6ff;
    --grey-900: #111827;
    --grey-700: #374151;
    --grey-500: #6b7280;
    --grey-300: #d1d5db;
    --grey-100: #f3f4f6;
    --white: #ffffff;
    --font: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', sans-serif;
}

html {
    scroll-behavior: smooth;
    -webkit-font-smoothing: antialiased;
    -moz-osx-font-smoothing: grayscale;
}

body {
    font-family: var(--font);
    color: var(--grey-900);
    background: var(--white);
    line-height: 1.6;
    font-size: 17px;
}

.container {
    max-width: 1120px;
    margin: 0 auto;
    padding: 0 24px;
}

/* ── Typography ── */
h1, h2, h3 {
    font-weight: 600;
    letter-spacing: -0.02em;
    line-height: 1.2;
}

.section-title {
    font-size: 2.5rem;
    text-align: center;
    margin-bottom: 56px;
    color: var(--grey-900);
}

/* ── Buttons ── */
.btn {
    display: inline-block;
    background: var(--blue-600);
    color: var(--white);
    padding: 12px 28px;
    border-radius: 980px;
    text-decoration: none;
    font-weight: 500;
    font-size: 0.95rem;
    border: none;
    cursor: pointer;
    transition: background 0.2s ease, transform 0.15s ease;
}

.btn:hover {
    background: var(--blue-500);
    transform: scale(1.02);
}

.btn-lg {
    padding: 16px 40px;
    font-size: 1.05rem;
}

.btn-sm {
    padding: 8px 20px;
    font-size: 0.875rem;
}

/* ── Header ── */
.header {
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    z-index: 100;
    background: rgba(255, 255, 255, 0.85);
    backdrop-filter: blur(20px);
    -webkit-backdrop-filter: blur(20px);
    border-bottom: 1px solid rgba(0, 0, 0, 0.06);
}

.nav {
    display: flex;
    align-items: center;
    justify-content: space-between;
    height: 64px;
}

.logo {
    font-size: 1.35rem;
    font-weight: 600;
    color: var(--grey-900);
    text-decoration: none;
    letter-spacing: -0.03em;
}

.nav-links {
    display: flex;
    align-items: center;
    gap: 32px;
    list-style: none;
}

.nav-links a {
    color: var(--grey-700);
    text-decoration: none;
    font-size: 0.9rem;
    font-weight: 450;
    transition: color 0.2s ease;
}

.nav-links a:hover {
    color: var(--grey-900);
}

/* ── Hero ── */
.hero {
    padding: 180px 0 140px;
    text-align: center;
    background: linear-gradient(180deg, var(--blue-50) 0%, var(--white) 100%);
}

.hero-title {
    font-size: 3.75rem;
    font-weight: 700;
    color: var(--grey-900);
    margin-bottom: 24px;
    letter-spacing: -0.035em;
    line-height: 1.1;
}

.hero-subtitle {
    font-size: 1.25rem;
    color: var(--grey-500);
    max-width: 560px;
    margin: 0 auto 40px;
    line-height: 1.6;
    font-weight: 400;
}

/* ── Services ── */
.services {
    padding: 120px 0;
}

.services-grid {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 40px;
}

.service-card {
    padding: 40px 32px;
    border-radius: 16px;
    background: var(--grey-100);
    transition: transform 0.2s ease, box-shadow 0.2s ease;
}

.service-card:hover {
    transform: translateY(-4px);
    box-shadow: 0 12px 40px rgba(0, 0, 0, 0.06);
}

.service-icon {
    width: 56px;
    height: 56px;
    display: flex;
    align-items: center;
    justify-content: center;
    background: var(--blue-100);
    color: var(--blue-600);
    border-radius: 14px;
    margin-bottom: 24px;
}

.service-card h3 {
    font-size: 1.2rem;
    margin-bottom: 12px;
    color: var(--grey-900);
}

.service-card p {
    color: var(--grey-500);
    font-size: 0.95rem;
    line-height: 1.6;
}

/* ── About ── */
.about {
    padding: 120px 0;
    background: var(--grey-100);
}

.about-content {
    max-width: 720px;
    margin: 0 auto;
    text-align: center;
}

.about-lead {
    font-size: 1.35rem;
    font-weight: 500;
    color: var(--grey-900);
    margin-bottom: 20px;
    line-height: 1.5;
}

.about-content p {
    color: var(--grey-500);
    font-size: 1.05rem;
    line-height: 1.7;
}

/* ── Contact ── */
.contact {
    padding: 120px 0;
}

.contact-subtitle {
    text-align: center;
    color: var(--grey-500);
    font-size: 1.1rem;
    margin-top: -40px;
    margin-bottom: 48px;
}

.contact-form {
    max-width: 600px;
    margin: 0 auto;
    display: flex;
    flex-direction: column;
    gap: 16px;
}

.form-row {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 16px;
}

.contact-form input,
.contact-form textarea {
    width: 100%;
    padding: 16px 20px;
    border: 1px solid var(--grey-300);
    border-radius: 12px;
    font-family: var(--font);
    font-size: 0.95rem;
    color: var(--grey-900);
    background: var(--white);
    transition: border-color 0.2s ease, box-shadow 0.2s ease;
    outline: none;
}

.contact-form input::placeholder,
.contact-form textarea::placeholder {
    color: var(--grey-500);
}

.contact-form input:focus,
.contact-form textarea:focus {
    border-color: var(--blue-500);
    box-shadow: 0 0 0 3px rgba(59, 130, 246, 0.1);
}

.contact-form textarea {
    resize: vertical;
    min-height: 120px;
}

.contact-form .btn {
    align-self: flex-start;
}

/* ── Footer ── */
.footer {
    padding: 32px 0;
    border-top: 1px solid rgba(0, 0, 0, 0.06);
}

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

.footer-text {
    color: var(--grey-500);
    font-size: 0.85rem;
}

/* ── Responsive ── */
@media (max-width: 768px) {
    .hero-title {
        font-size: 2.5rem;
    }

    .hero-subtitle {
        font-size: 1.1rem;
    }

    .hero {
        padding: 140px 0 100px;
    }

    .section-title {
        font-size: 2rem;
    }

    .services-grid {
        grid-template-columns: 1fr;
        gap: 24px;
    }

    .services, .about, .contact {
        padding: 80px 0;
    }

    .form-row {
        grid-template-columns: 1fr;
    }

    .nav-links {
        gap: 20px;
    }

    .footer-content {
        flex-direction: column;
        gap: 12px;
        text-align: center;
    }
}

@media (max-width: 480px) {
    .hero-title {
        font-size: 2rem;
    }

    .nav-links a:not(.btn) {
        display: none;
    }
}