/*******************/
/* GLOBAL VARIABLES */
/*******************/

:root {
    /* Colors */
    --primary-dark-blue: #0a192f;
    --primary-light-blue: #64ffda;
    --accent-orange-yellow: #ffcc00;
    
    /* Container Variants */
    --glass-white: rgba(255, 255, 255, 0.1);
    --glass-black: rgba(0, 0, 0, 0.3);
    
    /* Typography */
    --text-main: #e6f1ff;
    --text-dark: #0a192f;
    
    /* Layout */
    --border-radius: 15px;
    --header-height: 70px;
    --border-width: 2px; /* Added variable for easier global control */
}

/* BASIC RESET */

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

body {
    background-color: var(--primary-dark-blue);
    color: var(--text-main);
    font-family: 'Segoe UI', Roboto, Helvetica, Arial, sans-serif;
    line-height: 1.6;
    overflow-x: hidden;
}

/* FIXED HEADER */

header {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: var(--header-height);
    background-color: rgba(10, 25, 47, 0.95); /* Slightly transparent dark blue */
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 0 20px;
    z-index: 1000;
    border-bottom: 1px solid var(--primary-light-blue);
}

.logo {
    font-weight: bold;
    font-size: 1.2rem;
    color: var(--primary-light-blue);
    text-decoration: none;
}

nav ul {
    display: flex;
    list-style: none;
    gap: 20px;
}

nav a {
    color: var(--text-main);
    text-decoration: none;
    font-size: 0.9rem;
    transition: color 0.3s ease;
}

nav a:hover, nav a.active-link {
    color: var(--accent-orange-yellow);
}

/* Mobile Nav Toggle */
.menu-toggle {
    display: none; /* Hidden on desktop */
    cursor: pointer;
    font-size: 1.5rem;
    color: var(--primary-light-blue);
}

/*******************/
/* HERO CAROUSEL   */
/*******************/

.hero-carousel {
    position: relative;
    width: 100%;
    height: 80vh; /* 80% of viewport height */
    min-height: 400px;
    overflow: hidden;
    margin-bottom: 40px;
    border-radius: 0 0 var(--border-radius) var(--border-radius);
}

.hero-slide {
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background-size: cover;
    background-position: center;
    opacity: 0;
    transition: opacity 0.8s ease-in-out;
    display: flex;
    align-items: center;
    justify-content: center;
    text-align: center;
    z-index: 1;
}

.hero-slide.active {
    opacity: 1;
    z-index: 2;
}

.hero-overlay {
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background: linear-gradient(to bottom, rgba(10, 25, 47, 0.3), rgba(10, 25, 47, 0.8));
    z-index: -1;
}

.hero-content {
    max-width: 800px;
    padding: 0 20px;
    color: var(--text-main);
}

.hero-content h1 {
    font-size: clamp(2rem, 8vw, 3.5rem);
    margin-bottom: 20px;
    line-height: 1.2;
}

.hero-content p {
    font-size: clamp(1rem, 4vw, 1.25rem);
    margin-bottom: 30px;
    opacity: 0.9;
}

/* Carousel Controls */
.carousel-controls {
    position: absolute;
    bottom: 30px;
    left: 0;
    width: 100%;
    display: flex;
    justify-content: center;
    align-items: center;
    gap: 20px;
    z-index: 10;
}

.ctrl-btn {
    background: rgba(0, 0, 0, 0.5);
    color: white;
    border: 1px solid var(--primary-light-blue);
    width: 40px;
    height: 40px;
    border-radius: 50%;
    cursor: pointer;
    font-size: 1rem;
    transition: background 0.3s;
}

.ctrl-btn:hover {
    background: var(--primary-light-blue);
    color: var(--text-dark);
}

.carousel-dots {
    display: flex;
    gap: 10px;
}

.dot {
    width: 10px;
    height: 10px;
    background: rgba(255, 255, 255, 0.4);
    border-radius: 50%;
    cursor: pointer;
    transition: background 0.3s;
}

.dot.active {
    background: var(--accent-orange-yellow);
}

/* CONTENT CARDS */

.main-container {
    padding: calc(var(--header-height) + 20px) 20px 80px;
    max-width: 1200px;
    margin: 0 auto;
}

.content-card {
    margin-bottom: 30px;
    padding: 20px;
    border-radius: var(--border-radius);
    transition: transform 0.3s ease;
}

/* Variant A: Light Glass */
.card-light {
    background-color: var(--glass-white);
    border: var(--border-width) solid var(--text-main);
    color: var(--text-main);
}

/* Variant B: Dark Glass */
.card-dark {
    background-color: var(--glass-black);
    border: var(--border-width) solid var(--primary-light-blue);
    color: var(--primary-light-blue);
}

/* BUTTONS / CTAs */

.btn-cta {
    display: inline-block;
    background-color: var(--accent-orange-yellow);
    color: var(--text-dark);
    padding: 12px 24px;
    border-radius: 5px;
    text-decoration: none;
    font-weight: bold;
    text-align: center;
    transition: opacity 0.3s ease;
    border: none;
    cursor: pointer;
}

.btn-cta:hover {
    opacity: 0.9;
}

/*******************/
/* PRODUCT PAGE    */
/*******************/

.product-hero {
    margin-bottom: 40px;
}

.product-hero h1 {
    font-size: clamp(2rem, 6vw, 3rem);
    color: var(--primary-light-blue);
}

.section-label {
    font-size: 1.2rem;
    margin-bottom: 20px;
    color: var(--text-main);
    text-align: center;
}

.options-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
    gap: 20px;
    margin-bottom: 40px;
}

.option-tile {
    background-color: var(--glass-white);
    border: var(--border-width) solid var(--text-main);
    border-radius: var(--border-radius);
    padding: 20px;
    cursor: pointer;
    transition: all 0.3s ease;
    text-align: center;
}

.option-tile:hover {
    background-color: rgba(255, 255, 255, 0.2);
}

.option-tile.active {
    border-color: var(--accent-orange-yellow);
    box-shadow: 0 0 15px rgba(255, 204, 0, 0.3);
    background-color: rgba(255, 204, 0, 0.1);
}

.option-tile h3 {
    color: var(--primary-light-blue);
    margin-bottom: 10px;
}

.option-tile p {
    font-size: 0.9rem;
    opacity: 0.8;
}

/* Tech Specs Table */
.specs-table {
    width: 100%;
    border-collapse: collapse;
    margin-top: 20px;
}

.specs-table td {
    padding: 12px;
    border-bottom: 1px solid rgba(100, 255, 218, 0.2);
}

.specs-table td:first-child {
    font-weight: bold;
    color: var(--primary-light-blue);
    width: 40%;
}

/* STICKY BUY BAR */
.sticky-buy-bar {
    position: fixed;
    bottom: 0;
    left: 0;
    width: 100%;
    background-color: rgba(10, 25, 47, 0.9);
    backdrop-filter: blur(10px);
    border-top: 1px solid var(--primary-light-blue);
    padding: 15px 20px;
    z-index: 1000;
}

.buy-bar-content {
    max-width: 1200px;
    margin: 0 auto;
    display: flex;
    justify-content: space-between;
    align-items: center;
}

.selection-summary {
    font-size: 0.9rem;
    color: var(--text-main);
    font-style: italic;
}

/*******************/
/* CONTACT FORM    */
/*******************/

.contact-form {
    display: flex;
    flex-direction: column;
    gap: 20px;
    max-width: 600px;
    margin: 0 auto;
}

.form-group {
    display: flex;
    flex-direction: column;
    gap: 8px;
}

.form-group label {
    font-size: 0.9rem;
    color: var(--primary-light-blue);
}

.form-group input, 
.form-group textarea {
    background-color: rgba(0, 0, 0, 0.2);
    border: 1px solid var(--text-main);
    border-radius: 8px;
    padding: 12px;
    color: var(--text-main);
    font-family: inherit;
    transition: border-color 0.3s ease;
}

.form-group input:focus, 
.form-group textarea:focus {
    outline: none;
    border-color: var(--accent-orange-yellow);
}

/* RESPONSIVENESS */

@media (max-width: 768px) {
    .menu-toggle {
        display: block;
    }

    nav ul {
        display: none;
        position: absolute;
        top: var(--header-height);
        left: 0;
        width: 100%;
        background-color: var(--primary-dark-blue);
        flex-direction: column;
        padding: 20px;
        text-align: center;
        border-bottom: 1px solid var(--primary-light-blue);
    }

    nav ul.active {
        display: flex;
    }

    .buy-bar-content {
        flex-direction: column;
        gap: 15px;
        text-align: center;
    }
}