:root {
    --primary: #ff6b35;
    --secondary: #1a1a1a;
    --accent: #ffd700;
    --light: #f8f9fa;
    --gradient: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
}

* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
    font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
}

body {
    background: var(--gradient);
    color: var(--light);
    overflow-x: hidden;
}

/* Alert Container */
.alert-container {
    position: fixed;
    top: 20px;
    right: 20px;
    z-index: 9999;
    max-width: 350px;
}

.alert {
    box-shadow: 0 4px 15px rgba(0, 0, 0, 0.2);
    border: none;
    border-radius: 10px;
    animation: alertSlideIn 0.5s ease;
}

@keyframes alertSlideIn {
    from {
        transform: translateX(100%);
        opacity: 0;
    }
    to {
        transform: translateX(0);
        opacity: 1;
    }
}

.alert-success {
    background: linear-gradient(135deg, #2ecc71, #27ae60);
    color: white;
}

.alert-info {
    background: linear-gradient(135deg, #3498db, #2980b9);
    color: white;
}

.alert-warning {
    background: linear-gradient(135deg, #f39c12, #e67e22);
    color: white;
}

.alert-danger {
    background: linear-gradient(135deg, #e74c3c, #c0392b);
    color: white;
}

/* Navigation */
.navbar {
    background: rgba(26, 26, 26, 0.95);
    backdrop-filter: blur(10px);
    box-shadow: 0 4px 20px rgba(0, 0, 0, 0.3);
    transition: all 0.3s;
}

.navbar-brand {
    font-weight: bold;
    color: var(--primary);
    font-size: 1.8rem;
}

.nav-link {
    color: var(--light);
    font-weight: 500;
    transition: all 0.3s;
}

.nav-link:hover {
    color: var(--primary);
    transform: translateY(-2px);
}

.text-primary {
    color: var(--primary) !important;
}

.text-accent {
    color: var(--accent) !important;
}

/* Hero Section */
.hero {
    min-height: 100vh;
    display: flex;
    align-items: center;
    background: linear-gradient(rgba(0, 0, 0, 0.6), rgba(0, 0, 0, 0.4));
    background-size: cover;
    background-position: center;
}

.hero-content h1 {
    font-size: 3.5rem;
    font-weight: 900;
    margin-bottom: 1.5rem;
    text-shadow: 3px 3px 6px rgba(0, 0, 0, 0.7);
}

.hero-content p {
    font-size: 1.2rem;
    margin-bottom: 2rem;
}

.btn-hero {
    background: var(--primary);
    border: none;
    padding: 15px 40px;
    font-size: 1.2rem;
    font-weight: bold;
    border-radius: 50px;
    transition: all 0.3s;
    box-shadow: 0 8px 25px rgba(255, 107, 53, 0.3);
    color: white;
}

.btn-hero:hover {
    transform: translateY(-3px);
    box-shadow: 0 12px 35px rgba(255, 107, 53, 0.4);
    color: white;
}

/* Image Slider */
.slider-container {
    position: relative;
    border-radius: 15px;
    overflow: hidden;
    box-shadow: 0 15px 35px rgba(0, 0, 0, 0.3);
    height: 400px;
}

.slider {
    display: flex;
    transition: transform 0.5s ease;
    height: 100%;
}

.slide {
    min-width: 100%;
    height: 100%;
}

.slide img {
    width: 100%;
    height: 100%;
    object-fit: cover;
}

.slider-nav {
    position: absolute;
    bottom: 20px;
    left: 50%;
    transform: translateX(-50%);
    display: flex;
    gap: 10px;
}

.slider-dot {
    width: 12px;
    height: 12px;
    border-radius: 50%;
    background: rgba(255, 255, 255, 0.5);
    cursor: pointer;
    transition: background 0.3s;
}

.slider-dot.active {
    background: var(--primary);
}

/* Cards */
.card {
    background: rgba(255, 255, 255, 0.1);
    backdrop-filter: blur(10px);
    border: 1px solid rgba(255, 255, 255, 0.2);
    border-radius: 20px;
    padding: 2rem;
    transition: all 0.3s;
    height: 100%;
}

.card:hover {
    transform: translateY(-10px);
}

.card-icon {
    font-size: 3rem;
    color: var(--primary);
    margin-bottom: 1rem;
}

/* BMI Calculator */
.bmi-calc {
    background: rgba(26, 26, 26, 0.9);
    backdrop-filter: blur(15px);
    border-radius: 25px;
    padding: 2rem;
    box-shadow: 0 25px 50px rgba(0, 0, 0, 0.3);
    border: 2px solid rgba(255, 107, 53, 0.3);
}

.form-control {
    background: rgba(255, 255, 255, 0.1);
    border: 2px solid rgba(255, 255, 255, 0.2);
    border-radius: 15px;
    color: var(--light);
    padding: 12px 20px;
}

.form-control:focus {
    background: rgba(255, 255, 255, 0.15);
    border-color: var(--primary);
    box-shadow: 0 0 20px rgba(255, 107, 53, 0.3);
    color: var(--light);
}

/* Fix for gender select - remove transparency */
select.form-control {
    background: rgba(40, 40, 40, 0.95) !important;
    appearance: auto !important;
    -webkit-appearance: menulist !important;
    -moz-appearance: menulist !important;
}

select.form-control option {
    background: #2a2a2a !important;
    color: white !important;
    padding: 10px !important;
}

/* Ensure dropdown is visible and properly styled */
select.form-control:focus {
    background: rgba(50, 50, 50, 0.95) !important;
}

.form-label {
    color: var(--accent);
    font-weight: 600;
    margin-bottom: 0.8rem;
}

.bmi-result {
    background: rgba(255, 107, 53, 0.1);
    border: 2px solid var(--primary);
    border-radius: 20px;
    padding: 2rem;
    text-align: center;
    margin-top: 2rem;
    display: none;
}

.bmi-value {
    font-size: 3rem;
    font-weight: bold;
    color: var(--primary);
}

.bmi-category {
    font-size: 1.5rem;
    margin: 1rem 0;
    padding: 10px 20px;
    border-radius: 25px;
    font-weight: bold;
}

.underweight { 
    background: #3498db; 
    color: white; 
}

.normal { 
    background: #2ecc71; 
    color: white; 
}

.overweight { 
    background: #f39c12; 
    color: white; 
}

.obese { 
    background: #e74c3c; 
    color: white; 
}

/* Footer */
footer {
    background: var(--secondary);
    border-top: 3px solid var(--primary);
    padding: 3rem 0 1rem;
}

footer h5 {
    color: var(--primary);
    margin-bottom: 1rem;
}

.social-links {
    margin-bottom: 1rem;
}

.social-links a {
    display: inline-block;
    width: 40px;
    height: 40px;
    background: rgba(255, 255, 255, 0.1);
    border-radius: 50%;
    text-align: center;
    line-height: 40px;
    color: white;
    margin-right: 10px;
    transition: all 0.3s;
}

.social-links a:hover {
    background: var(--primary);
    transform: translateY(-3px);
}

/* Responsive */
@media (max-width: 768px) {
    .hero-content h1 {
        font-size: 2.5rem;
    }
    
    .hero-content p {
        font-size: 1rem;
    }
    
    .btn-hero {
        padding: 10px 25px;
        font-size: 1rem;
    }
    
    .alert-container {
        left: 20px;
        right: 20px;
        max-width: none;
    }
    
    footer .col-md-4 {
        margin-bottom: 2rem;
    }
    
    .slider-container {
        height: 300px;
        margin-top: 2rem;
    }
}