:root {
    --brand-dark: #2a2b25; /* màu chính (đen) */
    --brand-accent: #ffe484; /* vàng nhấn */
    --muted: #6c757d;
    --bg: #ffffff;
}

body {
    font-family: Inter, system-ui, -apple-system, "Segoe UI", Roboto,
        "Helvetica Neue", Arial;
    color: var(--brand-dark);
    background: var(--bg);
    -webkit-font-smoothing: antialiased;
    -moz-osx-font-smoothing: grayscale;
}

/* Navbar */
.navbar {
    background: #fff;
}
.navbar-brand {
    color: var(--brand-dark) !important;
    font-weight: 700;
}
.nav-link {
    color: var(--brand-dark) !important;
}
.nav-link.active {
    font-weight: 600;
    color: var(--brand-dark) !important;
}

/* Hero */
.hero {
    background: linear-gradient(135deg, var(--brand-dark), #3a3b35);
    color: #fff;
    padding: 4rem 0;
}
.hero .display-6 {
    color: var(--brand-accent);
}
.hero .lead {
    color: rgba(255, 255, 255, 0.92);
}

/* Buttons */
.btn-primary {
    background: var(--brand-accent);
    color: var(--brand-dark);
    border: none;
}
.btn-primary:hover {
    opacity: 0.95;
}

.btn-outline-secondary {
    border-color: rgba(0, 0, 0, 0.08);
    color: var(--brand-dark);
}

/* General sections */
.section-title h2 {
    color: var(--brand-dark);
}
.text-muted {
    color: var(--muted) !important;
}

/* Feature / Doctor cards */
.feature-card img {
    max-height: 200px;
    object-fit: cover;
}
.card-doctor img {
    height: 220px;
    object-fit: cover;
}
.card .card-title {
    color: var(--brand-dark);
}
.feature-card .card-body p {
    color: var(--muted);
}

/* Footer */
footer {
    background: var(--brand-dark);
    color: #fff;
    padding: 20px 0;
}

.floating-phone {
    position: fixed;
    right: 18px;
    bottom: 18px;
    background: var(--brand-accent);
    color: var(--brand-dark);
    border-radius: 50%;
    width: 56px;
    height: 56px;
    display: flex;
    align-items: center;
    justify-content: center;
    box-shadow: 0 6px 18px rgba(0, 0, 0, 0.12);
}

@media (prefers-color-scheme: dark) {
    body {
        background: #0f0f0f;
        color: #ddd;
    }
}