/* =========================================================
   Mediabank — CSS
   Brand colors: blue #2563EB · orange #F97316
   ========================================================= */

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

:root {
    --blue:          #2563EB;
    --blue-light:    #DBEAFE;
    --blue-mid:      #3B82F6;
    --orange:        #F97316;
    --orange-dark:   #EA580C;
    --orange-light:  #FFEDD5;
    --text:          #1C2431;
    --text-muted:    #6B7280;
    --bg:            #FFFFFF;
    --bg-alt:        #F8FAFF;
    --bg-dark:       #0F1623;
    --border:        #E5E7EB;
    --radius:        12px;
    --radius-sm:     8px;
    --shadow:        0 4px 24px rgba(37, 99, 235, 0.08);
    --shadow-lg:     0 8px 48px rgba(37, 99, 235, 0.14);
    --transition:    0.2s ease;
    --container:     1080px;
    --font:          'Inter', system-ui, -apple-system, BlinkMacSystemFont, 'Segoe UI', sans-serif;
}

html {
    scroll-behavior: smooth;
    -webkit-text-size-adjust: 100%;
}

body {
    font-family: var(--font);
    font-size: 16px;
    line-height: 1.6;
    color: var(--text);
    background: var(--bg);
    overflow-x: hidden;
}

img {
    max-width: 100%;
    height: auto;
    display: block;
}

a {
    color: inherit;
    text-decoration: none;
}

/* ----- Container ----- */
.container {
    width: 90%;
    max-width: var(--container);
    margin-inline: auto;
}

/* ----- Buttons ----- */
.btn {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    gap: 8px;
    font-family: var(--font);
    font-size: 15px;
    font-weight: 600;
    line-height: 1;
    border-radius: var(--radius-sm);
    border: 2px solid transparent;
    cursor: pointer;
    transition: background var(--transition), color var(--transition),
                border-color var(--transition), transform var(--transition),
                box-shadow var(--transition);
    white-space: nowrap;
    text-decoration: none;
}

.btn:hover { transform: translateY(-1px); }
.btn:active { transform: translateY(0); }

.btn--primary {
    background: var(--blue);
    color: #fff;
    border-color: var(--blue);
}
.btn--primary:hover {
    background: #1D4ED8;
    border-color: #1D4ED8;
    box-shadow: 0 4px 20px rgba(37, 99, 235, 0.35);
}

.btn--outline {
    background: transparent;
    color: var(--blue);
    border-color: var(--blue);
}
.btn--outline:hover {
    background: var(--blue-light);
}

.btn--sm  { padding: 8px 18px; font-size: 14px; }
.btn--lg  { padding: 14px 32px; font-size: 16px; }

/* ----- Section typography ----- */
.section-title {
    font-size: clamp(24px, 4vw, 36px);
    font-weight: 700;
    color: var(--text);
    text-align: center;
    margin-bottom: 12px;
    letter-spacing: -0.5px;
}

.section-subtitle {
    font-size: 17px;
    color: var(--text-muted);
    text-align: center;
    margin-bottom: 40px;
}

/* =========================================================
   HEADER
   ========================================================= */
.header {
    position: sticky;
    top: 0;
    z-index: 100;
    background: rgba(255, 255, 255, 0.92);
    backdrop-filter: blur(12px);
    -webkit-backdrop-filter: blur(12px);
    border-bottom: 1px solid var(--border);
    transition: box-shadow var(--transition);
}

.header.scrolled {
    box-shadow: 0 2px 16px rgba(0,0,0,0.08);
}

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

.header__logo img {
    height: 32px;
    width: auto;
}

.header__nav {
    display: flex;
    align-items: center;
    gap: 28px;
}

.header__nav-link {
    font-size: 15px;
    font-weight: 500;
    color: var(--text-muted);
    transition: color var(--transition);
}
.header__nav-link:hover { color: var(--blue); }

/* Burger (mobile) */
.header__burger {
    display: none;
    flex-direction: column;
    justify-content: center;
    gap: 5px;
    width: 36px;
    height: 36px;
    background: none;
    border: none;
    cursor: pointer;
    padding: 4px;
}
.header__burger span {
    display: block;
    height: 2px;
    background: var(--text);
    border-radius: 2px;
    transition: transform var(--transition), opacity var(--transition);
}
.header__burger.open span:nth-child(1) { transform: translateY(7px) rotate(45deg); }
.header__burger.open span:nth-child(2) { opacity: 0; }
.header__burger.open span:nth-child(3) { transform: translateY(-7px) rotate(-45deg); }

/* Mobile nav overlay */
.header__nav.mobile-open {
    display: flex;
    flex-direction: column;
    align-items: flex-start;
    position: fixed;
    inset: 64px 0 0;
    background: var(--bg);
    padding: 32px 5%;
    gap: 24px;
    border-top: 1px solid var(--border);
}
.header__nav.mobile-open .header__nav-link {
    font-size: 18px;
    color: var(--text);
}

/* =========================================================
   HERO
   ========================================================= */
.hero {
    padding: 100px 0 80px;
    text-align: center;
    background: linear-gradient(160deg, #FFFFFF 60%, #EFF6FF 100%);
}

.hero__inner { max-width: 680px; margin-inline: auto; }

.hero__logo-wrap {
    margin-bottom: 36px;
}
.hero__logo {
    max-width: 280px;
    margin-inline: auto;
}

.hero__tagline {
    font-size: clamp(18px, 2.5vw, 22px);
    color: var(--text-muted);
    line-height: 1.55;
    margin-bottom: 40px;
}

.hero__actions {
    display: flex;
    align-items: center;
    justify-content: center;
    gap: 16px;
    flex-wrap: wrap;
}

/* =========================================================
   ABOUT / FEATURES
   ========================================================= */
.about {
    padding: 80px 0;
    background: var(--bg);
}

.about__intro {
    font-size: clamp(17px, 2vw, 20px);
    line-height: 1.65;
    color: var(--text);
    text-align: center;
    max-width: 760px;
    margin-inline: auto;
    margin-bottom: 60px;
}

.features-grid {
    display: grid;
    grid-template-columns: repeat(2, 1fr);
    gap: 24px;
}

.feature-card {
    background: var(--bg-alt);
    border: 1px solid var(--border);
    border-radius: var(--radius);
    padding: 32px 28px;
    transition: box-shadow var(--transition), transform var(--transition);
}
.feature-card:hover {
    box-shadow: var(--shadow);
    transform: translateY(-2px);
}

.feature-card__num {
    font-size: 48px;
    font-weight: 700;
    line-height: 1;
    color: var(--blue);
    margin-bottom: 16px;
    font-feature-settings: "tnum";
}
.feature-card__num--orange { color: var(--orange); }

.feature-card p {
    font-size: 15px;
    color: var(--text-muted);
    line-height: 1.65;
}

/* =========================================================
   HOW IT WORKS
   ========================================================= */
.how-it-works {
    padding: 80px 0;
    background: var(--bg-alt);
}

.formats {
    display: flex;
    flex-wrap: wrap;
    justify-content: center;
    gap: 10px;
    margin-bottom: 56px;
}

.format-tag {
    background: var(--bg);
    border: 1.5px solid var(--border);
    border-radius: 6px;
    padding: 5px 14px;
    font-size: 13px;
    font-weight: 600;
    color: var(--text);
    letter-spacing: 0.3px;
}
.format-tag--muted {
    border-color: transparent;
    color: var(--text-muted);
    font-weight: 400;
}

.arch-layout {
    display: grid;
    grid-template-columns: 1fr 340px;
    gap: 48px;
    align-items: center;
}

.arch-layout__screenshot img {
    border-radius: var(--radius);
    box-shadow: var(--shadow-lg);
    width: 100%;
}

.arch-layout__cards {
    display: flex;
    flex-direction: column;
    gap: 20px;
}

.arch-card {
    display: flex;
    gap: 16px;
    background: var(--bg);
    border: 1px solid var(--border);
    border-radius: var(--radius);
    padding: 20px;
    transition: box-shadow var(--transition);
}
.arch-card:hover { box-shadow: var(--shadow); }

.arch-card__icon {
    flex-shrink: 0;
    width: 48px;
    height: 48px;
    border-radius: var(--radius-sm);
    display: flex;
    align-items: center;
    justify-content: center;
}
.arch-card__icon--blue { background: var(--blue-light); }
.arch-card__icon--orange   { background: var(--orange-light); }

.arch-card__body h3 {
    font-size: 15px;
    font-weight: 600;
    margin-bottom: 6px;
    color: var(--text);
}
.arch-card__body p {
    font-size: 13px;
    color: var(--text-muted);
    line-height: 1.6;
}

/* =========================================================
   DOCUMENT FEATURES
   ========================================================= */
.doc-features {
    padding: 80px 0;
    background: var(--bg);
}

.doc-features__grid {
    display: grid;
    grid-template-columns: repeat(2, 1fr);
    gap: 32px;
    margin-bottom: 48px;
}

.doc-feature {
    padding: 28px 24px;
    border-radius: var(--radius);
    border: 1px solid var(--border);
    background: var(--bg-alt);
    position: relative;
    overflow: hidden;
}

.doc-feature::before {
    content: '';
    position: absolute;
    top: 0; left: 0;
    width: 4px;
    height: 100%;
    background: var(--blue);
    border-radius: 4px 0 0 4px;
}
.doc-feature:nth-child(2)::before { background: var(--orange); }

.doc-feature__indicator {
    width: 10px;
    height: 10px;
    border-radius: 50%;
    background: var(--blue);
    margin-bottom: 14px;
}
.doc-feature__indicator--orange { background: var(--orange); }

.doc-feature h3 {
    font-size: 17px;
    font-weight: 600;
    margin-bottom: 10px;
    color: var(--text);
}
.doc-feature p {
    font-size: 14px;
    color: var(--text-muted);
    line-height: 1.65;
}

.doc-features__screenshot {
    border-radius: var(--radius);
    overflow: hidden;
    box-shadow: var(--shadow-lg);
    margin-bottom: 32px;
}
.doc-features__screenshot img { width: 100%; }

.doc-features__note {
    display: flex;
    align-items: flex-start;
    gap: 12px;
    background: var(--orange-light);
    border: 1px solid rgba(249, 115, 22, 0.3);
    border-radius: var(--radius);
    padding: 16px 20px;
}
.doc-features__note-icon { flex-shrink: 0; margin-top: 1px; }
.doc-features__note p {
    font-size: 14px;
    color: var(--text);
    line-height: 1.6;
}

/* =========================================================
   DEMO VIDEO
   ========================================================= */
.demo {
    padding: 80px 0;
    background: var(--bg-alt);
}

.demo__video-wrap {
    position: relative;
    width: 100%;
    max-width: 800px;
    margin-inline: auto;
    padding-bottom: min(450px, 56.25%);
    height: 0;
    border-radius: var(--radius);
    overflow: hidden;
    box-shadow: var(--shadow-lg);
}
.demo__video-wrap iframe {
    position: absolute;
    inset: 0;
    width: 100%;
    height: 100%;
    border: none;
}

/* =========================================================
   CONTACTS
   ========================================================= */
.contacts {
    padding: 100px 0;
    background: var(--bg-dark);
    color: #fff;
    text-align: center;
}

.contacts__logo {
    margin-bottom: 40px;
}
.contacts__logo img {
    margin-inline: auto;
    /* invert to show on dark background */
    filter: brightness(0) invert(1);
}

.contacts__title {
    font-size: clamp(26px, 4vw, 40px);
    font-weight: 700;
    margin-bottom: 12px;
    color: #fff;
}
.contacts__sub {
    font-size: 17px;
    color: rgba(255,255,255,0.55);
    margin-bottom: 48px;
}

.contacts__links {
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: 16px;
    margin-bottom: 60px;
}

.contacts__item {
    display: inline-flex;
    align-items: center;
    gap: 10px;
    font-size: 20px;
    font-weight: 500;
    color: #fff;
    padding: 14px 28px;
    border-radius: var(--radius);
    border: 1.5px solid rgba(255,255,255,0.15);
    transition: background var(--transition), border-color var(--transition);
}
.contacts__item:hover {
    background: rgba(255,255,255,0.06);
    border-color: rgba(255,255,255,0.3);
}
.contacts__item svg { opacity: 0.6; }

.contacts__brand {
    display: flex;
    align-items: center;
    justify-content: center;
    gap: 12px;
    color: rgba(255,255,255,0.4);
    font-size: 14px;
}
.contacts__brand img {
    height: 24px;
    /* keep colorful geekchain logo readable on dark bg */
    opacity: 0.85;
}

/* =========================================================
   FOOTER
   ========================================================= */
.footer {
    background: #080D16;
    padding: 20px 0;
    text-align: center;
}
.footer p {
    font-size: 13px;
    color: rgba(255,255,255,0.3);
}
.footer a {
    color: rgba(255,255,255,0.5);
    transition: color var(--transition);
}
.footer a:hover { color: var(--orange); }

/* =========================================================
   RESPONSIVE
   ========================================================= */

/* Tablet ≤ 900px */
@media (max-width: 900px) {
    .arch-layout {
        grid-template-columns: 1fr;
    }
    .arch-layout__cards {
        flex-direction: row;
        flex-wrap: wrap;
    }
    .arch-card { flex: 1 1 260px; }
}

/* Tablet ≤ 768px */
@media (max-width: 768px) {
    .header__nav {
        display: none;
    }
    .header__burger { display: flex; }

    .hero { padding: 72px 0 60px; }
    .hero__logo { max-width: 220px; }
    .hero__tagline br { display: none; }
    .hero__tagline { font-size: 17px; }

    .features-grid {
        grid-template-columns: 1fr;
        gap: 16px;
    }

    .doc-features__grid {
        grid-template-columns: 1fr;
        gap: 16px;
    }

    .contacts__item { font-size: 17px; padding: 12px 20px; }
}

/* Mobile ≤ 480px */
@media (max-width: 480px) {
    .hero { padding: 56px 0 48px; }
    .hero__logo { max-width: 180px; }

    .about { padding: 56px 0; }
    .about__intro { font-size: 16px; }

    .how-it-works,
    .doc-features,
    .demo { padding: 56px 0; }

    .contacts { padding: 72px 0; }

    .btn--lg { padding: 13px 24px; font-size: 15px; }

    .arch-layout__cards { flex-direction: column; }

    .section-title { font-size: 22px; }
    .section-subtitle { font-size: 15px; }
}