:root {
    /* Trainer Palette */
    --primary: #007BFF;
    /* Active Blue */
    --secondary: #1A1A1A;
    /* Dark Grey */
    --accent: #FFD700;
    /* Gold Medal */
    --bg-body: #F4F4F4;
    --bg-card: #FFFFFF;
    --text-main: #333333;
    --text-light: #666666;

    /* Typography */
    --font-heading: 'Oswald', sans-serif;
    --font-body: 'Open Sans', sans-serif;

    /* Spacing */
    --container-width: 1100px;
    --header-height: 80px;

    /* UI */
    --radius: 8px;
    --shadow: 0 5px 20px rgba(0, 0, 0, 0.1);
}

[data-theme="female-fitness"] {
    --primary: #FF6B6B;
    /* Coral */
    --secondary: #2D3436;
    --accent: #FFEAA7;
    --bg-body: #FFF5F5;
}

[data-theme="dark-mode"] {
    --primary: #00D2D3;
    /* Cyan */
    --secondary: #FFFFFF;
    --bg-body: #222F3E;
    --bg-card: #2C3A47;
    --text-main: #C8D6E5;
    --text-light: #8395A7;
}

* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

body {
    font-family: var(--font-body);
    background-color: var(--bg-body);
    color: var(--text-main);
    line-height: 1.6;
}

h1,
h2,
h3,
h4 {
    font-family: var(--font-heading);
    text-transform: uppercase;
    font-weight: 700;
}

/* Header */
header {
    height: var(--header-height);
    background: white;
    box-shadow: 0 2px 10px rgba(0, 0, 0, 0.05);
    position: sticky;
    top: 0;
    z-index: 100;
    display: flex;
    align-items: center;
}

[data-theme="dark-mode"] header {
    background: #2C3A47;
}

.container {
    max-width: var(--container-width);
    margin: 0 auto;
    padding: 0 2rem;
    width: 100%;
}

.nav-flex {
    display: flex;
    justify-content: space-between;
    align-items: center;
}

.logo {
    font-family: var(--font-heading);
    font-size: 1.8rem;
    color: var(--primary);
    text-decoration: none;
    font-style: italic;
}

.nav-links {
    display: flex;
    gap: 2rem;
    list-style: none;
}

.nav-links a {
    color: var(--text-main);
    text-decoration: none;
    font-weight: 600;
    transition: color 0.3s;
}

.nav-links a:hover {
    color: var(--primary);
}

/* Hero */
.hero {
    padding: 6rem 0;
    display: flex;
    align-items: center;
    gap: 4rem;
}

.hero-content {
    flex: 1;
}

.hero h1 {
    font-size: 4rem;
    line-height: 1.1;
    margin-bottom: 1.5rem;
}

.hero p {
    font-size: 1.2rem;
    color: var(--text-light);
    margin-bottom: 2rem;
}

.hero-img {
    flex: 1;
    position: relative;
}

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

.btn {
    display: inline-block;
    padding: 1rem 2.5rem;
    background: var(--primary);
    color: white;
    text-decoration: none;
    border-radius: 50px;
    font-weight: 700;
    text-transform: uppercase;
    transition: transform 0.2s;
}

.btn:hover {
    transform: translateY(-3px);
}

/* Before/After Slider (Simulated) */
.transformations {
    padding: 6rem 0;
    text-align: center;
    background: var(--bg-card);
}

.slider-container {
    display: flex;
    gap: 2rem;
    overflow-x: auto;
    padding: 2rem 0;
    scroll-snap-type: x mandatory;
}

.slide-card {
    min-width: 300px;
    background: var(--bg-body);
    padding: 1rem;
    border-radius: var(--radius);
    scroll-snap-align: center;
}

.slide-img {
    width: 100%;
    height: 300px;
    object-fit: cover;
    border-radius: var(--radius);
    margin-bottom: 1rem;
}

/* Calculator */
.calculator {
    padding: 6rem 0;
    background: var(--primary);
    color: white;
    text-align: center;
}

.calc-box {
    background: white;
    color: var(--text-main);
    max-width: 500px;
    margin: 2rem auto 0;
    padding: 2rem;
    border-radius: var(--radius);
    box-shadow: var(--shadow);
}

.form-group {
    margin-bottom: 1rem;
    text-align: left;
}

.form-group label {
    display: block;
    font-size: 0.8rem;
    font-weight: 700;
    margin-bottom: 0.5rem;
}

.form-control {
    width: 100%;
    padding: 0.8rem;
    border: 1px solid #ddd;
    border-radius: 4px;
}

/* Pricing */
.pricing {
    padding: 6rem 0;
}

.price-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
    gap: 2rem;
}

.price-card {
    background: var(--bg-card);
    padding: 2rem;
    border-radius: var(--radius);
    text-align: center;
    border: 1px solid #eee;
    transition: transform 0.3s;
}

[data-theme="dark-mode"] .price-card {
    border-color: #444;
}

.price-card:hover {
    transform: translateY(-10px);
    border-color: var(--primary);
}

.price-amount {
    font-size: 3rem;
    font-family: var(--font-heading);
    color: var(--primary);
    display: block;
    margin: 1rem 0;
}

/* Footer */
footer {
    padding: 4rem 0;
    text-align: center;
    background: var(--secondary);
    color: white;
}

@media (max-width: 768px) {
    .hero {
        flex-direction: column;
        text-align: center;
    }

    .nav-links {
        display: none;
    }
}