/* =========================================
   ITInfraCore - Modern Cloud Infrastructure
   ========================================= */

:root {
    --color-primary: #2563eb;
    --color-primary-dark: #1d4ed8;
    --color-primary-light: #3b82f6;
    --color-accent: #06b6d4;
    --color-bg: #0f172a;
    --color-bg-light: #1e293b;
    --color-bg-card: #162032;
    --color-text: #f8fafc;
    --color-text-muted: #94a3b8;
    --color-border: rgba(148, 163, 184, 0.15);
    --gradient-primary: linear-gradient(135deg, var(--color-primary) 0%, var(--color-accent) 100%);
    --shadow-sm: 0 1px 2px rgba(0,0,0,0.3);
    --shadow-md: 0 4px 6px -1px rgba(0,0,0,0.3), 0 2px 4px -2px rgba(0,0,0,0.3);
    --shadow-lg: 0 10px 15px -3px rgba(0,0,0,0.3), 0 4px 6px -4px rgba(0,0,0,0.3);
    --radius: 12px;
    --radius-sm: 8px;
    --max-width: 1200px;
    --header-height: 72px;
    --transition: 0.25s ease;
}

* { margin: 0; padding: 0; box-sizing: border-box; }
html { scroll-behavior: smooth; scroll-padding-top: var(--header-height); }
body {
    font-family: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, sans-serif;
    background-color: var(--color-bg); color: var(--color-text); line-height: 1.6; -webkit-font-smoothing: antialiased;
}
a { color: var(--color-primary-light); text-decoration: none; transition: color var(--transition); }
a:hover { color: var(--color-accent); }
.container { width: 100%; max-width: var(--max-width); margin: 0 auto; padding: 0 24px; }

/* Buttons */
.btn {
    display: inline-flex; align-items: center; justify-content: center;
    padding: 12px 28px; border-radius: var(--radius-sm);
    font-weight: 600; font-size: 0.95rem; cursor: pointer; border: none;
    transition: all var(--transition); text-decoration: none;
}
.btn-primary { background: var(--gradient-primary); color: white; box-shadow: 0 4px 14px rgba(37,99,235,0.4); }
.btn-primary:hover { transform: translateY(-2px); box-shadow: 0 6px 20px rgba(37,99,235,0.5); color: white; }
.btn-secondary { background: transparent; color: var(--color-text); border: 1.5px solid var(--color-border); }
.btn-secondary:hover { border-color: var(--color-primary-light); color: var(--color-primary-light); }
.btn-outline { background: transparent; color: var(--color-primary-light); border: 1.5px solid var(--color-primary); }
.btn-outline:hover { background: var(--color-primary); color: white; }
.btn-full { width: 100%; }

/* Header */
.header {
    position: fixed; top: 0; left: 0; width: 100%; height: var(--header-height);
    background: rgba(15,23,42,0.85); backdrop-filter: blur(16px); -webkit-backdrop-filter: blur(16px);
    border-bottom: 1px solid var(--color-border); z-index: 1000; transition: background var(--transition);
}
.header-inner { display: flex; align-items: center; justify-content: space-between; height: 100%; }
.logo { display: flex; align-items: center; gap: 8px; font-weight: 800; font-size: 1.35rem; color: var(--color-text); text-decoration: none; }
.logo-icon { display: flex; align-items: center; justify-content: center; width: 36px; height: 36px; background: var(--gradient-primary); border-radius: var(--radius-sm); color: white; font-size: 0.9rem; }
.logo-text { letter-spacing: -0.5px; }
.nav-list { display: flex; list-style: none; gap: 32px; }
.nav-list a { color: var(--color-text-muted); font-weight: 500; font-size: 0.95rem; position: relative; }
.nav-list a::after { content: ''; position: absolute; bottom: -4px; left: 0; width: 0; height: 2px; background: var(--gradient-primary); transition: width var(--transition); border-radius: 2px; }
.nav-list a:hover { color: var(--color-text); }
.nav-list a:hover::after { width: 100%; }
.mobile-menu-toggle { display: none; flex-direction: column; gap: 5px; background: none; border: none; cursor: pointer; padding: 4px; }
.mobile-menu-toggle span { display: block; width: 24px; height: 2px; background: var(--color-text); border-radius: 2px; transition: all var(--transition); }

/* Hero */
.hero { position: relative; min-height: 100vh; display: flex; align-items: center; justify-content: center; text-align: center; padding: calc(var(--header-height) + 40px) 24px 80px; overflow: hidden; }
.hero-bg { position: absolute; inset: 0; background: radial-gradient(ellipse at 20% 30%, rgba(37,99,235,0.12) 0%, transparent 50%), radial-gradient(ellipse at 80% 70%, rgba(6,182,212,0.08) 0%, transparent 50%); pointer-events: none; }
.hero-content { position: relative; z-index: 1; max-width: 800px; }
.hero h1 { font-size: clamp(2.2rem, 5vw, 3.6rem); font-weight: 800; line-height: 1.15; letter-spacing: -1.5px; margin-bottom: 20px; }
.hero h1 .accent { background: var(--gradient-primary); -webkit-background-clip: text; -webkit-text-fill-color: transparent; background-clip: text; }
.hero-subtitle { font-size: clamp(1rem, 2vw, 1.25rem); color: var(--color-text-muted); margin-bottom: 36px; max-width: 640px; margin-left: auto; margin-right: auto; }
.hero-cta { display: flex; gap: 16px; justify-content: center; flex-wrap: wrap; }

/* Sections */
.section-title { font-size: clamp(1.6rem, 3vw, 2.4rem); font-weight: 800; text-align: center; margin-bottom: 12px; letter-spacing: -0.5px; }
.section-subtitle { color: var(--color-text-muted); text-align: center; max-width: 560px; margin: 0 auto 56px; font-size: 1.05rem; }
.features { padding: 100px 0; }
.features-grid { display: grid; grid-template-columns: repeat(3, 1fr); gap: 24px; }
.feature-card { background: var(--color-bg-card); border: 1px solid var(--color-border); border-radius: var(--radius); padding: 40px 32px; transition: all var(--transition); }
.feature-card:hover { transform: translateY(-6px); box-shadow: var(--shadow-lg); border-color: rgba(37,99,235,0.3); }
.feature-icon { width: 64px; height: 64px; display: flex; align-items: center; justify-content: center; background: rgba(37,99,235,0.1); border-radius: var(--radius-sm); color: var(--color-primary-light); margin-bottom: 24px; }
.feature-card h3 { font-size: 1.2rem; font-weight: 700; margin-bottom: 12px; }
.feature-card p { color: var(--color-text-muted); font-size: 0.95rem; margin-bottom: 20px; }
.feature-list { list-style: none; }
.feature-list li { color: var(--color-text-muted); font-size: 0.9rem; padding: 6px 0; display: flex; align-items: center; gap: 8px; }
.feature-list li::before { content: '\2713'; color: var(--color-accent); font-weight: bold; }

/* Pricing */
.pricing { padding: 100px 0; background: var(--color-bg-light); }
.pricing-grid { display: grid; grid-template-columns: repeat(3, 1fr); gap: 24px; align-items: start; }
.pricing-card { background: var(--color-bg-card); border: 1px solid var(--color-border); border-radius: var(--radius); padding: 36px 32px; position: relative; transition: all var(--transition); }
.pricing-card:hover { transform: translateY(-4px); box-shadow: var(--shadow-lg); }
.pricing-card.featured { border-color: var(--color-primary); background: linear-gradient(180deg, rgba(37,99,235,0.08) 0%, var(--color-bg-card) 100%); }
.popular-badge { position: absolute; top: -12px; right: 24px; background: var(--gradient-primary); color: white; font-size: 0.75rem; font-weight: 700; padding: 6px 14px; border-radius: 20px; text-transform: uppercase; letter-spacing: 0.5px; }
.pricing-header { text-align: center; margin-bottom: 28px; padding-bottom: 24px; border-bottom: 1px solid var(--color-border); }
.pricing-header h3 { font-size: 1.3rem; font-weight: 700; margin-bottom: 8px; }
.pricing-desc { color: var(--color-text-muted); font-size: 0.9rem; margin-bottom: 16px; }
.pricing-price { display: flex; align-items: baseline; justify-content: center; gap: 2px; }
.pricing-price .currency { font-size: 1.2rem; font-weight: 600; color: var(--color-text-muted); }
.pricing-price .amount { font-size: 2.6rem; font-weight: 800; letter-spacing: -1px; }
.pricing-price .period { color: var(--color-text-muted); font-size: 0.9rem; }
.pricing-features { list-style: none; margin-bottom: 28px; }
.pricing-features li { padding: 10px 0; display: flex; align-items: center; gap: 10px; color: var(--color-text-muted); font-size: 0.95rem; border-bottom: 1px solid rgba(148,163,184,0.07); }
.pricing-features li:last-child { border-bottom: none; }
.pricing-features .check { color: var(--color-accent); font-weight: bold; }
.pricing-note { text-align: center; color: var(--color-text-muted); font-size: 0.85rem; margin-top: 32px; }

/* About */
.about { padding: 100px 0; }
.about-inner { display: grid; grid-template-columns: 1fr 1fr; gap: 64px; align-items: center; }
.about-text p { color: var(--color-text-muted); margin-bottom: 24px; }
.about-list { list-style: none; }
.about-list li { padding: 10px 0; color: var(--color-text-muted); display: flex; gap: 8px; }
.about-list li::before { content: '\2022'; color: var(--color-primary-light); font-weight: bold; }
.about-stats { display: grid; grid-template-columns: repeat(2, 1fr); gap: 24px; }
.stat { background: var(--color-bg-card); border: 1px solid var(--color-border); border-radius: var(--radius); padding: 28px; text-align: center; }
.stat-number { display: block; font-size: 1.8rem; font-weight: 800; background: var(--gradient-primary); -webkit-background-clip: text; -webkit-text-fill-color: transparent; background-clip: text; margin-bottom: 6px; }
.stat-label { color: var(--color-text-muted); font-size: 0.9rem; }

/* Contact */
.contact { padding: 100px 0; background: var(--color-bg-light); }
.contact-grid { display: grid; grid-template-columns: 1fr 1fr; gap: 56px; align-items: start; }
.contact-info { display: flex; flex-direction: column; gap: 28px; }
.contact-item { display: flex; align-items: flex-start; gap: 16px; }
.contact-icon { width: 48px; height: 48px; display: flex; align-items: center; justify-content: center; background: rgba(37,99,235,0.1); border-radius: var(--radius-sm); color: var(--color-primary-light); flex-shrink: 0; }
.contact-label { display: block; color: var(--color-text-muted); font-size: 0.85rem; margin-bottom: 4px; }
.contact-value { color: var(--color-text); font-weight: 500; font-size: 1.05rem; }
.contact-form { background: var(--color-bg-card); border: 1px solid var(--color-border); border-radius: var(--radius); padding: 40px; }
.form-group { margin-bottom: 20px; }
.form-group label { display: block; font-size: 0.9rem; font-weight: 500; margin-bottom: 8px; }
.form-group input, .form-group select, .form-group textarea {
    width: 100%; padding: 12px 16px; background: var(--color-bg);
    border: 1px solid var(--color-border); border-radius: var(--radius-sm);
    color: var(--color-text); font-family: inherit; font-size: 0.95rem;
    transition: border-color var(--transition);
}
.form-group input:focus, .form-group select:focus, .form-group textarea:focus { outline: none; border-color: var(--color-primary); }
.form-group input::placeholder, .form-group textarea::placeholder { color: var(--color-text-muted); opacity: 0.6; }
.form-group select { cursor: pointer; appearance: none; background-image: url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' width='16' height='16' viewBox='0 0 24 24' fill='none' stroke='%2394a3b8' stroke-width='2' stroke-linecap='round' stroke-linejoin='round'%3E%3Cpolyline points='6 9 12 15 18 9'%3E%3C/polyline%3E%3C/svg%3E"); background-repeat: no-repeat; background-position: right 14px center; padding-right: 40px; }
.error-message { display: block; color: #f87171; font-size: 0.8rem; margin-top: 6px; min-height: 1em; }
.form-note { color: var(--color-text-muted); font-size: 0.85rem; text-align: center; margin-top: 16px; }

/* Footer */
.footer { padding: 64px 0 0; border-top: 1px solid var(--color-border); }
.footer-inner { display: grid; grid-template-columns: 2fr 1fr 1fr; gap: 40px; margin-bottom: 48px; }
.footer-brand p { color: var(--color-text-muted); margin-top: 16px; max-width: 320px; font-size: 0.95rem; }
.footer-links h4 { font-size: 1rem; font-weight: 700; margin-bottom: 20px; }
.footer-links ul { list-style: none; }
.footer-links li { margin-bottom: 12px; }
.footer-links a { color: var(--color-text-muted); font-size: 0.95rem; }
.footer-links a:hover { color: var(--color-text); }
.footer-bottom { border-top: 1px solid var(--color-border); padding: 24px 0; text-align: center; }
.footer-bottom p { color: var(--color-text-muted); font-size: 0.85rem; }

/* Back to top */
.back-to-top {
    position: fixed; bottom: 24px; right: 24px; width: 44px; height: 44px;
    background: var(--color-bg-card); border: 1px solid var(--color-border);
    border-radius: var(--radius-sm); display: flex; align-items: center; justify-content: center;
    color: var(--color-text-muted); opacity: 0; visibility: hidden;
    transition: all var(--transition); z-index: 999; cursor: pointer;
}
.back-to-top.visible { opacity: 1; visibility: visible; }
.back-to-top:hover { background: var(--color-primary); color: white; border-color: var(--color-primary); }

/* Mobile */
@media (max-width: 992px) {
    .features-grid, .pricing-grid { grid-template-columns: repeat(2, 1fr); }
    .about-inner, .contact-grid { grid-template-columns: 1fr; }
    .about-stats { max-width: 500px; }
}
@media (max-width: 768px) {
    .nav { display: none; position: absolute; top: var(--header-height); left: 0; width: 100%; background: rgba(15,23,42,0.98); backdrop-filter: blur(16px); border-bottom: 1px solid var(--color-border); padding: 20px 24px; }
    .nav.active { display: block; }
    .nav-list { flex-direction: column; gap: 16px; }
    .mobile-menu-toggle { display: flex; }
    .hero-cta { flex-direction: column; }
    .features-grid, .pricing-grid, .about-inner, .contact-grid, .footer-inner { grid-template-columns: 1fr; }
    .pricing-card.featured { order: -1; }
    .about-stats { max-width: 100%; }
    .footer-inner { gap: 32px; text-align: center; }
    .footer-brand { display: flex; flex-direction: column; align-items: center; }
}