/* 
   ==========================================================================
   BIO-INSPIRED RESEARCH PLATFORM - MASTER STYLESHEET
   Author: Abdullah Khatip
   Design System: Scientific Modernism (Clean, High Contrast, Accessible)
   ==========================================================================
*/

/* 1. THEME VARIABLES - THE ENGINE OF THE SITE */
:root {
    /* Light Mode Palette */
    --bg-color: #fcfcfc;            /* Soft white background */
    --nav-bg: #ffffff;              /* Pure white for navbar */
    --card-bg: #ffffff;             /* Pure white for cards */
    --text-main: #1a1a1a;           /* Deep black for readability */
    --text-muted: #555555;          /* Grey for secondary text */
    --accent-color: #0056b3;        /* Professional scientific blue */
    --accent-hover: #003d7a;        /* Darker blue for hover effects */
    --border-color: #e0e0e0;        /* Light grey borders */
    --shadow: 0 4px 12px rgba(0, 0, 0, 0.08);
    --transition: all 0.3s cubic-bezier(0.4, 0, 0.2, 1);
}

[data-theme="dark"] {
    /* Dark Mode Palette */
    --bg-color: #121212;            /* Deep charcoal background */
    --nav-bg: #1e1e1e;              /* Slightly lighter grey for navbar */
    --card-bg: #1e1e1e;             /* Matching dark card background */
    --text-main: #f5f5f5;           /* Soft white for readability */
    --text-muted: #b0b0b0;          /* Light grey for secondary text */
    --accent-color: #bb86fc;        /* Soft purple/lavender for dark mode */
    --accent-hover: #9965f4;        /* Darker purple */
    --border-color: #333333;        /* Dark borders */
    --shadow: 0 4px 12px rgba(0, 0, 0, 0.5);
}

/* 2. GLOBAL RESET & BASE STYLES */
* {
    box-sizing: border-box;
    margin: 0;
    padding: 0;
}

body {
    background-color: var(--bg-color);
    color: var(--text-main);
    font-family: 'Inter', 'Segoe UI', Roboto, Helvetica, Arial, sans-serif;
    line-height: 1.6;
    transition: background-color 0.4s ease, color 0.4s ease;
}

/* 3. TYPOGRAPHY */
h1, h2, h3, h4 {
    color: var(--text-main);
    margin-bottom: 1rem;
    font-weight: 700;
    transition: color 0.4s ease;
}

p {
    color: var(--text-muted);
    margin-bottom: 1.5rem;
    transition: color 0.4s ease;
}

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

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

/* 4. NAVIGATION BAR */
nav {
    background-color: var(--nav-bg);
    border-bottom: 1px solid var(--border-color);
    padding: 1rem 2rem;
    display: flex;
    justify-content: space-between;
    align-items: center;
    position: sticky;
    top: 0;
    z-index: 1000;
    box-shadow: var(--shadow);
    transition: var(--transition);
}

/* 5. THEME TOGGLE BUTTON - PROFESSIONAL DESIGN */
#theme-toggle {
    cursor: pointer;
    padding: 8px 16px;
    border-radius: 25px;
    border: 2px solid var(--accent-color);
    background: transparent;
    color: var(--text-main);
    font-weight: 600;
    font-size: 0.9rem;
    transition: var(--transition);
    outline: none;
}

#theme-toggle:hover {
    background-color: var(--accent-color);
    color: #fff;
    transform: translateY(-2px);
}

#theme-toggle:active {
    transform: scale(0.95);
}

/* 6. CARDS & SECTIONS (For your project pages) */
.container {
    max-width: 1100px;
    margin: 2rem auto;
    padding: 0 20px;
}

.card {
    background-color: var(--card-bg);
    border: 1px solid var(--border-color);
    border-radius: 12px;
    padding: 2rem;
    margin-bottom: 2rem;
    box-shadow: var(--shadow);
    transition: var(--transition);
}

.card:hover {
    transform: translateY(-5px);
    box-shadow: 0 8px 24px rgba(0, 0, 0, 0.15);
}

/* 7. RESPONSIVENESS */
@media (max-width: 768px) {
    nav {
        flex-direction: column;
        gap: 1rem;
        text-align: center;
    }
}