/* --- American Courier - Modern Corporate Theme --- */
:root {
    --font-primary: 'Inter', system-ui, -apple-system, sans-serif;
    
    /* Modern Palette */
    --color-bg-body: #FFFFFF;
    --color-bg-light: #F4F7FA;     /* Very subtle blue-grey for sections */
    --color-bg-dark: #0A192F;      /* Deep Navy for Footer/Hero */
    
    --color-brand-red: #D90429;    /* Vivid American Red */
    --color-brand-navy: #003049;   /* Professional Navy Blue */
    --color-brand-accent: #669BBC; /* Soft Blue for accents */
    
    --color-text-main: #1D1D1F;
    --color-text-secondary: #4A5568;
    --color-text-light: #E2E8F0;

    --header-height: 80px;
    --container-width: 1200px;
    --border-radius-pill: 50px;
    --border-radius-card: 12px;
    --shadow-card: 0 4px 6px -1px rgba(0, 0, 0, 0.1), 0 2px 4px -1px rgba(0, 0, 0, 0.06);
    --shadow-hover: 0 20px 25px -5px rgba(0, 0, 0, 0.1), 0 10px 10px -5px rgba(0, 0, 0, 0.04);
    --transition: all 0.3s ease;
}

html { scroll-behavior: smooth; box-sizing: border-box; }
*, *:before, *:after { box-sizing: inherit; }

body {
    font-family: var(--font-primary);
    background-color: var(--color-bg-body);
    color: var(--color-text-main);
    line-height: 1.6;
    margin: 0;
    -webkit-font-smoothing: antialiased;
}

/* --- Typography --- */
h1, h2, h3, h4 {
    color: var(--color-brand-navy);
    font-weight: 800;
    margin-top: 0;
    margin-bottom: 1rem;
    line-height: 1.2;
}

h1 { font-size: 2.5rem; letter-spacing: -1px; }
h2 { font-size: 2rem; margin-bottom: 1.5rem; }
h3 { font-size: 1.5rem; }
h4 { font-size: 1.25rem; }

p { color: var(--color-text-secondary); margin-bottom: 1.5rem; font-size: 1rem; }

@media (min-width: 768px) {
    h1 { font-size: 3.5rem; }
    h2 { font-size: 2.5rem; }
    p { font-size: 1.1rem; }
}

a { color: var(--color-brand-red); text-decoration: none; font-weight: 600; transition: var(--transition); }
a:hover { color: var(--color-brand-navy); }

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

/* --- Layout --- */
.container { 
    width: 100%;
    max-width: var(--container-width); 
    margin: 0 auto; 
    padding: 0 1.5rem; 
}

section { padding: 4rem 0; }
@media (min-width: 768px) { section { padding: 6rem 0; } }

.bg-light { background-color: var(--color-bg-light); }

/* --- Navigation --- */
.main-header { 
    position: fixed; top: 0; left: 0; width: 100%; height: var(--header-height);
    display: flex; align-items: center; justify-content: space-between;
    padding: 0 1.5rem; z-index: 1000;
    background-color: rgba(255, 255, 255, 0.95);
    backdrop-filter: blur(10px);
    border-bottom: 1px solid rgba(0,0,0,0.05);
    box-shadow: 0 4px 20px rgba(0,0,0,0.03);
}

.logo { 
    display: flex; align-items: center; 
    font-weight: 900; font-size: 1.2rem; 
    color: var(--color-brand-navy); 
    text-transform: uppercase; letter-spacing: -0.5px; 
}
.logo-img { height: 100px; width: auto; margin-right: 10px; }

/* Desktop Menu */
.nav-links-desktop { display: none; gap: 2rem; align-items: center; }
.nav-links-desktop a { color: var(--color-text-main); font-size: 0.95rem; font-weight: 600; }
.nav-links-desktop a:hover { color: var(--color-brand-red); }

.hamburger-menu { 
    font-size: 1.5rem; color: var(--color-brand-navy); 
    cursor: pointer; display: block; 
}

@media(min-width: 900px) { 
    .nav-links-desktop { display: flex; } 
    .hamburger-menu { display: none; } 
    .logo { font-size: 1.5rem; }
}

/* --- Buttons --- */
.btn {
    display: inline-flex; align-items: center; justify-content: center;
    padding: 12px 30px;
    background-color: var(--color-brand-navy); color: white;
    border-radius: var(--border-radius-pill);
    font-weight: 700; text-transform: uppercase; font-size: 0.9rem; letter-spacing: 0.5px;
    border: 2px solid var(--color-brand-navy);
    transition: var(--transition);
    text-align: center;
    cursor: pointer;
}
.btn:hover { background-color: transparent; color: var(--color-brand-navy); transform: translateY(-2px); }

.btntrack {
    display: inline-flex; align-items: center; justify-content: center;
    padding: 12px 30px;
    background-color: var(--color-brand-red); color: white;
    border-radius: var(--border-radius-pill);
    font-weight: 700; text-transform: uppercase; font-size: 0.9rem; letter-spacing: 0.5px;
    border: 2px solid var(--color-brand-red);
    box-shadow: 0 4px 15px rgba(217, 4, 41, 0.3);
    transition: var(--transition);
    text-align: center;
    cursor: pointer;
}
.btntrack:hover { background-color: transparent; color: var(--color-brand-red); transform: translateY(-2px); box-shadow: 0 6px 20px rgba(217, 4, 41, 0.4); }

/* --- Hero Section --- */
.hero {
    min-height: 80vh; padding-top: var(--header-height);
    display: flex; align-items: center; justify-content: center;
    background: linear-gradient(135deg, var(--color-bg-dark) 0%, #162a47 100%);
    color: white; text-align: center; position: relative; overflow: hidden;
    padding-left: 1rem; padding-right: 1rem;
}
.hero::before {
    content: ''; position: absolute; top: 0; left: 0; width: 100%; height: 100%;
    background-image: url('https://images.unsplash.com/photo-1586528116311-ad8dd3c8310d?ixlib=rb-1.2.1&auto=format&fit=crop&w=1950&q=80');
    background-size: cover; background-position: center; opacity: 0.2; pointer-events: none;
}
.hero-content { position: relative; z-index: 1; max-width: 900px; margin: 0 auto; }
.hero-content h1 { color: white; margin-bottom: 1rem; }
.hero-content p { color: var(--color-text-light); font-size: 1.1rem; margin-bottom: 2rem; max-width: 700px; margin-left: auto; margin-right: auto; }

/* --- Grids & Cards --- */
.grid-cols-3, .grid-cols-4 {
    display: grid;
    grid-template-columns: 1fr;
    gap: 2rem;
}

@media (min-width: 640px) {
    .grid-cols-3, .grid-cols-4 { grid-template-columns: repeat(2, 1fr); }
}

@media (min-width: 1024px) {
    .grid-cols-3 { grid-template-columns: repeat(3, 1fr); }
    .grid-cols-4 { grid-template-columns: repeat(4, 1fr); }
}

.feature-card {
    background: white; padding: 2rem;
    border-radius: var(--border-radius-card);
    box-shadow: var(--shadow-card);
    border: 1px solid #eee; transition: var(--transition);
    position: relative; overflow: hidden;
    display: flex; flex-direction: column;
}
.feature-card::before { content: ''; position: absolute; top: 0; left: 0; width: 100%; height: 4px; background: var(--color-brand-red); transform: scaleX(0); transition: var(--transition); transform-origin: left; }
.feature-card:hover { transform: translateY(-5px); box-shadow: var(--shadow-hover); }
.feature-card:hover::before { transform: scaleX(1); }
.feature-card .icon { color: var(--color-brand-red); font-size: 2rem; margin-bottom: 1rem; }
.feature-card h3 { font-size: 1.3rem; margin-bottom: 0.5rem; }

/* --- Testimonials --- */
.testimonial-card {
    background: white; padding: 2rem; border-radius: var(--border-radius-card);
    border-left: 4px solid var(--color-brand-red);
    box-shadow: var(--shadow-card);
    height: 100%;
}
.testimonial-card p { font-style: italic; color: var(--color-text-main); margin-bottom: 1rem; }
.testimonial-card h4 { color: var(--color-brand-navy); margin-top: auto; font-size: 0.9rem; font-weight: 700; text-transform: uppercase; }

/* --- Footer --- */
.main-footer { background-color: var(--color-bg-dark); color: var(--color-text-light); padding: 4rem 0 2rem; }
.main-footer h4 { color: white; margin-bottom: 1rem; font-size: 1.1rem; }
.main-footer a { color: var(--color-text-light); font-weight: 400; opacity: 0.8; }
.main-footer a:hover { color: var(--color-brand-red); opacity: 1; }

.footer-grid { display: grid; grid-template-columns: 1fr; gap: 3rem; }
@media (min-width: 768px) {
    .footer-grid { grid-template-columns: 2fr 1fr 1fr; }
}

.footer-bottom { border-top: 1px solid rgba(255,255,255,0.1); margin-top: 3rem; padding-top: 2rem; text-align: center; font-size: 0.9rem; opacity: 0.6; }

/* --- Mobile Nav --- */
.nav-panel { 
    position: fixed; top: 0; left: 0; width: 100%; height: 100vh; 
    background: white; z-index: 2000; 
    display: flex; flex-direction: column; align-items: center; justify-content: center; 
    transform: translateX(100%); transition: var(--transition); 
}
.nav-panel.open { transform: translateX(0); }
.nav-links-mobile a { 
    font-size: 1.5rem; font-weight: 800; 
    color: var(--color-brand-navy); margin: 1rem 0; display: block; 
}
.close-menu-button { 
    position: absolute; top: 1.5rem; right: 1.5rem; 
    font-size: 2.5rem; cursor: pointer; color: var(--color-brand-navy);
}

/* --- Forms --- */
.form-input {
    width: 100%; padding: 12px 15px; margin-bottom: 1rem;
    border: 1px solid #ccc; border-radius: 8px;
    font-family: inherit; font-size: 1rem;
    transition: var(--transition);
}
.form-input:focus { outline: none; border-color: var(--color-brand-navy); box-shadow: 0 0 0 3px rgba(0, 48, 73, 0.1); }
.form-group label { display: block; margin-bottom: 0.5rem; font-weight: 600; color: var(--color-brand-navy); }

.contact-grid {
    display: grid; grid-template-columns: 1fr; gap: 3rem;
}
@media (min-width: 900px) {
    .contact-grid { grid-template-columns: 1fr 1fr; gap: 4rem; }
}

/* --- Animation --- */
.reveal { opacity: 0; transform: translateY(30px); transition: all 0.8s ease; }
.reveal.visible { opacity: 1; transform: translateY(0); }

/* --- Tracking Page Specifics --- */
.tracking-card {
    background: white; padding: 2rem; border-radius: var(--border-radius-card);
    box-shadow: var(--shadow-card); border: 1px solid #eee;
}
.tracking-header {
    display: flex; flex-direction: column; gap: 1rem; align-items: flex-start; justify-content: space-between; margin-bottom: 2rem;
}
@media(min-width: 640px) {
    .tracking-header { flex-direction: row; align-items: center; }
}
.tracking-details-grid {
    display: grid; grid-template-columns: 1fr; gap: 2rem; margin-top: 2rem;
}
@media(min-width: 768px) {
    .tracking-details-grid { grid-template-columns: 1fr 1fr; }
}