/* 
 * MediChatApp Modern Overhaul CSS v4
 * High-end SaaS Aesthetic + Navbar Fix + iPhone 16 Pro Max
 */
:root {
    --primary: #2563eb;
    --primary-dark: #1e40af;
    --secondary: #0f172a;
    --accent: #06b6d4;
    --text-main: #334155;
    --text-dark: #0f172a;
    --bg-light: #f8fafc;
    --white: #ffffff;
    --shadow-sm: 0 1px 2px 0 rgb(0 0 0 / 0.05);
    --shadow-md: 0 4px 6px -1px rgb(0 0 0 / 0.1), 0 2px 4px -2px rgb(0 0 0 / 0.1);
    --shadow-lg: 0 10px 15px -3px rgb(0 0 0 / 0.1), 0 4px 6px -4px rgb(0 0 0 / 0.1);
    --font-sans: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, sans-serif;
}
body {
    font-family: var(--font-sans);
    color: var(--text-main);
    line-height: 1.7;
    background-color: var(--white);
    -webkit-font-smoothing: antialiased;
    -moz-osx-font-smoothing: grayscale;
}
h1, h2, h3, h4, h5, h6 {
    color: var(--text-dark);
    font-weight: 700;
    letter-spacing: -0.025em;
}
.display-1, .display-2, .display-3, .display-4 {
    font-weight: 800;
    letter-spacing: -0.05em;
}
/* Improve text readability globally */
p, li, td, th, label, span, div {
    color: var(--text-main);
}
.text-muted {
    color: #64748b !important;
}

/* ===== NAVBAR: BULLETPROOF SINGLE LINE ===== */
.navbar-marketing {
    padding-top: .4rem !important;
    padding-bottom: .4rem !important;
    transition: all 0.3s ease;
    background: rgba(255, 255, 255, 0.97) !important;
    backdrop-filter: blur(12px);
    -webkit-backdrop-filter: blur(12px);
    border-bottom: 1px solid rgba(0,0,0,0.06);
    z-index: 1050;
}
/* Force the container to be a single-line flex row */
.navbar-marketing > .container {
    display: flex !important;
    flex-wrap: nowrap !important;
    align-items: center !important;
    justify-content: space-between !important;
    gap: 0 !important;
    padding-left: 1rem !important;
    padding-right: 1rem !important;
}
/* Brand + action buttons group: force single line */
.navbar-marketing .d-flex.align-items-center {
    display: flex !important;
    flex-wrap: nowrap !important;
    align-items: center !important;
    gap: .3rem !important;
    flex: 1 1 auto;
    min-width: 0;
    overflow: hidden;
}
/* Logo */
.navbar-marketing .navbar-brand {
    flex: 0 0 auto;
    padding: 0 !important;
    margin: 0 !important;
    line-height: 0;
}
.navbar-marketing .navbar-brand img {
    height: 30px !important;
    width: auto !important;
    display: block;
}
/* Action buttons next to logo */
.navbar-marketing .d-flex .btn-sm {
    font-size: .6rem !important;
    padding: .3rem .55rem !important;
    white-space: nowrap !important;
    flex-shrink: 0;
    border-radius: .375rem;
    font-weight: 600;
    line-height: 1.2;
}
/* Phone icon button */
.navbar-marketing .d-flex .btn-transparent {
    font-size: .7rem !important;
    padding: .2rem .3rem !important;
    width: auto !important;
    flex-shrink: 0;
    line-height: 1;
}
/* Hamburger toggle */
.navbar-marketing .navbar-toggler {
    padding: .2rem .35rem !important;
    font-size: .75rem !important;
    flex-shrink: 0;
    border: 1px solid rgba(0,0,0,.1);
    border-radius: .375rem;
    margin-left: .25rem;
}
.navbar-marketing .navbar-toggler-icon {
    width: 1em !important;
    height: 1em !important;
}
/* Nav links */
.navbar-marketing .nav-link {
    font-weight: 500;
    color: var(--text-dark) !important;
    padding: 0.5rem 0.875rem !important;
    transition: color 0.2s ease;
    font-size: 0.9rem;
}
.navbar-marketing .nav-link:hover {
    color: var(--primary) !important;
}

/* ===== MOBILE: Tablets and below ===== */
@media (max-width: 991.98px) {
    body { padding-top: 52px !important; }
    .navbar-marketing {
        padding-top: .3rem !important;
        padding-bottom: .3rem !important;
    }
    .navbar-marketing > .container {
        padding-left: .75rem !important;
        padding-right: .5rem !important;
    }
    .navbar-marketing .navbar-brand img {
        height: 24px !important;
    }
    .navbar-marketing .d-flex .btn-sm {
        font-size: .52rem !important;
        padding: .22rem .4rem !important;
    }
    .navbar-marketing .d-flex .btn-transparent {
        font-size: .6rem !important;
        padding: .15rem .25rem !important;
    }
    .navbar-marketing .navbar-toggler {
        padding: .15rem .28rem !important;
        font-size: .65rem !important;
    }
    .navbar-marketing .navbar-toggler-icon {
        width: .9em !important;
        height: .9em !important;
    }
    .page-header-ui {
        padding-top: 3rem !important;
        padding-bottom: 2rem !important;
    }
}

/* ===== iPhone 16 Pro Max and similar large phones (430px) ===== */
@media (max-width: 440px) {
    .navbar-marketing .d-flex.align-items-center {
        gap: .2rem !important;
    }
    .navbar-marketing .navbar-brand img {
        height: 20px !important;
    }
    .navbar-marketing .d-flex .btn-sm {
        font-size: .48rem !important;
        padding: .18rem .32rem !important;
        letter-spacing: 0;
    }
    .navbar-marketing .d-flex .btn-transparent {
        font-size: .55rem !important;
        padding: .12rem .2rem !important;
    }
    .navbar-marketing .navbar-toggler {
        padding: .12rem .22rem !important;
    }
    .navbar-marketing .navbar-toggler-icon {
        width: .85em !important;
        height: .85em !important;
    }
}

/* ===== Smaller phones (375px iPhone SE, etc.) ===== */
@media (max-width: 380px) {
    .navbar-marketing .navbar-brand img {
        height: 18px !important;
    }
    .navbar-marketing .d-flex .btn-sm {
        font-size: .42rem !important;
        padding: .15rem .25rem !important;
    }
    /* Hide phone icon on very small screens */
    .navbar-marketing .d-flex .btn-transparent {
        display: none !important;
    }
}

/* ===== BUTTONS ===== */
.btn {
    font-weight: 600;
    border-radius: 0.5rem;
    transition: all 0.2s ease;
}
.btn-primary {
    background-color: var(--primary);
    border-color: var(--primary);
    box-shadow: var(--shadow-sm);
}
.btn-primary:hover {
    background-color: var(--primary-dark);
    border-color: var(--primary-dark);
    transform: translateY(-1px);
    box-shadow: var(--shadow-md);
}

/* ===== HERO ===== */
.page-header-ui {
    padding: 8rem 0 6rem;
    background: radial-gradient(circle at top right, rgba(37, 99, 235, 0.05), transparent),
                radial-gradient(circle at bottom left, rgba(6, 182, 212, 0.05), transparent);
}
.page-header-ui-title {
    font-size: 3.5rem;
    line-height: 1.1;
    margin-bottom: 1.5rem;
}
.page-header-ui-text {
    font-size: 1.25rem;
    color: var(--text-main);
    margin-bottom: 2.5rem;
}

/* ===== CARDS ===== */
.card {
    border: none;
    border-radius: 1rem;
    box-shadow: var(--shadow-md);
    transition: transform 0.3s ease, box-shadow 0.3s ease;
}
.card:hover {
    transform: translateY(-5px);
    box-shadow: var(--shadow-lg);
}
.icon-stack {
    height: 3rem;
    width: 3rem;
    display: inline-flex;
    align-items: center;
    justify-content: center;
    border-radius: 0.75rem;
    margin-bottom: 1.5rem;
}

/* ===== SECTIONS ===== */
section {
    padding: 4rem 0;
}
section h2 {
    font-size: 2.25rem;
    margin-bottom: 1rem;
}
section .lead {
    font-size: 1.15rem;
    color: var(--text-main);
}

/* ===== FOOTER ===== */
.footer {
    background-color: var(--secondary) !important;
    color: rgba(255, 255, 255, 0.7);
    padding: 5rem 0 2rem;
}
.footer h6, .footer .footer-brand {
    color: var(--white) !important;
}
.footer a {
    color: rgba(255, 255, 255, 0.6);
    text-decoration: none;
    transition: color 0.2s ease;
}
.footer a:hover {
    color: var(--white);
}

/* ===== READABILITY: Ensure all text is high-contrast ===== */
.text-gray-700, .text-gray-600 {
    color: var(--text-main) !important;
}
.text-gray-800, .text-gray-900 {
    color: var(--text-dark) !important;
}
/* Fix any light-on-light text issues */
.bg-white p, .bg-white li, .bg-white span {
    color: var(--text-main);
}
.bg-light p, .bg-light li, .bg-light span {
    color: var(--text-main);
}