/*
===========================================
MAIN STYLESHEET
Custom CSS for WaveSense website (Redesign)
===========================================
*/

/* 
ROOT VARIABLES
Light & Dark themes, color scheme, typography
*/
:root {
    /* Light Theme (Default) */
    --bg-color: #ffffff;
    --text-color: #1a1a1a;
    --text-muted: #6b7280;
    --primary-color: #1E3A8A; /* Deep Blue from Spec */
    --primary-hover: #1e40af;
    --bg-alt: #f3f4f6;
    --border-color: #e5e7eb;
    
    --success-color: #16A34A;
    --error-color: #DC2626;
    
    --card-bg: #ffffff;
    --card-shadow: 0 4px 6px -1px rgba(0, 0, 0, 0.1), 0 2px 4px -1px rgba(0, 0, 0, 0.06);
    --card-shadow-hover: 0 10px 15px -3px rgba(0, 0, 0, 0.1), 0 4px 6px -2px rgba(0, 0, 0, 0.05);
    
    --font-heading: 'Inter', system-ui, -apple-system, sans-serif;
    --font-body: 'Inter', system-ui, -apple-system, sans-serif;
    --font-mono: 'JetBrains Mono', monospace;
    
    --max-width: 1200px;
    --transition-speed: 0.3s;
}

/* Dark Theme overrides */
[data-theme="dark"] {
    --bg-color: #121212;
    --text-color: #f3f4f6;
    --text-muted: #9ca3af;
    --primary-color: #3b82f6; /* Lighter blue for dark mode visibility */
    --primary-hover: #60a5fa;
    --bg-alt: #1e1e1e;
    --border-color: #374151;
    
    --card-bg: #1e1e1e;
    --card-shadow: 0 4px 6px -1px rgba(255, 255, 255, 0.05);
    --card-shadow-hover: 0 10px 15px -3px rgba(255, 255, 255, 0.1);
}

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

body {
    font-family: var(--font-body);
    line-height: 1.6;
    color: var(--text-color);
    background-color: var(--bg-color);
    transition: background-color var(--transition-speed), color var(--transition-speed);
    display: flex;
    flex-direction: column;
    min-height: 100vh;
}

main {
    flex: 1 0 auto;
    width: 100%;
    max-width: var(--max-width);
    margin: 0 auto;
    padding: 2rem;
}

footer {
    flex-shrink: 0;
    text-align: center;
    padding: 2rem;
    color: var(--text-muted);
    border-top: 1px solid var(--border-color);
    margin-top: 4rem;
}

/* 
TYPOGRAPHY
*/
h1, h2, h3, h4, h5, h6 {
    font-family: var(--font-heading);
    font-weight: 700;
    margin-bottom: 1rem;
    color: var(--text-color);
}

h1 { font-size: 2.5rem; }
h2 { font-size: 1.5rem; }
h3 { font-size: 1.25rem; }

p { margin-bottom: 1rem; }

a {
    color: var(--primary-color);
    text-decoration: none;
    transition: color var(--transition-speed);
}

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

code, pre {
    font-family: var(--font-mono);
    font-size: 0.9rem;
}

/* 
NAVIGATION
*/
.navbar {
    width: 100%;
    background-color: var(--bg-color);
    border-bottom: 1px solid var(--border-color);
    position: sticky;
    top: 0;
    z-index: 100;
    transition: background-color var(--transition-speed);
}

.nav-container {
    max-width: var(--max-width);
    margin: 0 auto;
    padding: 1rem 2rem;
    display: flex;
    justify-content: space-between;
    align-items: center;
}

.nav-brand img {
    height: 96px;
    object-fit: contain;
    transition: filter var(--transition-speed);
}

/* Make the white logo visible (black) in light mode */
html:not([data-theme="dark"]) .nav-brand img {
    filter: brightness(0);
}

.nav-links {
    display: flex;
    gap: 1.5rem;
    align-items: center;
}

.nav-links a {
    color: var(--text-muted);
    font-weight: 500;
}

.nav-links a:hover, .nav-links a.active {
    color: var(--text-color);
}

.nav-controls {
    display: flex;
    gap: 1rem;
    align-items: center;
}

/* Theme Toggle Button */
.theme-toggle {
    background: none;
    border: none;
    color: var(--text-color);
    cursor: pointer;
    font-size: 1.2rem;
    padding: 0.5rem;
}

/* Language Switcher */
.lang-switcher select {
    background-color: var(--bg-alt);
    color: var(--text-color);
    border: 1px solid var(--border-color);
    padding: 0.3rem 0.5rem;
    border-radius: 4px;
    font-family: var(--font-body);
    cursor: pointer;
}

/* Mobile Menu Toggle */
.mobile-menu-btn {
    display: none;
    background: none;
    border: none;
    color: var(--text-color);
    font-size: 1.5rem;
    cursor: pointer;
}

/* 
BUTTONS
*/
.btn {
    display: inline-block;
    padding: 0.75rem 1.5rem;
    border-radius: 6px;
    font-weight: 500;
    text-align: center;
    cursor: pointer;
    transition: all var(--transition-speed);
    border: 1px solid transparent;
}

.btn-primary {
    background-color: var(--primary-color);
    color: #ffffff;
}

.btn-primary:hover {
    background-color: var(--primary-hover);
    color: #ffffff;
    transform: translateY(-2px);
    box-shadow: 0 4px 6px rgba(0,0,0,0.1);
}

.btn-outline {
    background-color: transparent;
    color: var(--primary-color);
    border-color: var(--primary-color);
}

.btn-outline:hover {
    background-color: var(--primary-color);
    color: #ffffff;
    transform: translateY(-2px);
}

/* 
CARDS
*/
.card-grid {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(300px, 1fr));
    gap: 2rem;
    margin-top: 2rem;
}

.card {
    background-color: var(--card-bg);
    border-radius: 8px;
    border: 1px solid var(--border-color);
    padding: 1.5rem;
    transition: transform var(--transition-speed), box-shadow var(--transition-speed);
    box-shadow: var(--card-shadow);
    display: flex;
    flex-direction: column;
}

.card:hover {
    transform: translateY(-5px);
    box-shadow: var(--card-shadow-hover);
}

.card h3 {
    margin-bottom: 0.5rem;
}

.card p {
    color: var(--text-muted);
    flex-grow: 1;
}

/* 
FORMS
*/
.form-group {
    margin-bottom: 1.5rem;
}

.form-label {
    display: block;
    margin-bottom: 0.5rem;
    font-weight: 500;
}

.form-control {
    width: 100%;
    padding: 0.75rem;
    border: 1px solid var(--border-color);
    border-radius: 6px;
    background-color: var(--bg-alt);
    color: var(--text-color);
    font-family: var(--font-body);
    transition: border-color var(--transition-speed), box-shadow var(--transition-speed);
}

.form-control:focus {
    outline: none;
    border-color: var(--primary-color);
    box-shadow: 0 0 0 3px rgba(30, 58, 138, 0.1);
}

/* 
ALERTS/FLASH MESSAGES
*/
.alert {
    padding: 1rem;
    border-radius: 6px;
    margin-bottom: 1rem;
    border-left: 4px solid;
}

.alert-success {
    background-color: rgba(22, 163, 74, 0.1);
    color: var(--success-color);
    border-color: var(--success-color);
}

.alert-error, .alert-danger {
    background-color: rgba(220, 38, 38, 0.1);
    color: var(--error-color);
    border-color: var(--error-color);
}

/* 
UTILITIES & LAYOUT INFO
*/
.text-center { text-align: center; }
.mt-2 { margin-top: 2rem; }
.mb-2 { margin-bottom: 2rem; }
.py-4 { padding-top: 4rem; padding-bottom: 4rem; }

/* 
ANIMATIONS (Fade-in on scroll)
*/
.fade-in-section {
    opacity: 0;
    transform: translateY(20vh);
    visibility: hidden;
    transition: opacity 0.6s ease-out, transform 1.2s ease-out;
    will-change: opacity, visibility;
}
.fade-in-section.is-visible {
    opacity: 1;
    transform: none;
    visibility: visible;
}

/* 
RESPONSIVE DESIGN
*/
@media (max-width: 768px) {
    .nav-links {
        display: none; /* Hide by default on mobile, can be toggled via JS */
        flex-direction: column;
        position: absolute;
        top: 100%;
        left: 0;
        right: 0;
        background-color: var(--bg-color);
        padding: 1rem;
        border-bottom: 1px solid var(--border-color);
        box-shadow: 0 4px 6px rgba(0,0,0,0.05);
    }
    
    .nav-links.show {
        display: flex;
    }
    
    .mobile-menu-btn {
        display: block;
    }
    
    .card-grid {
        grid-template-columns: 1fr;
    }
}