/* Variables - Clinical/Teal Theme */
:root {
    --primary: #0d9488;      /* Clinical Teal */
    --primary-dark: #0f766e; /* Deep Teal */
    --secondary: #0284c7;    /* Hospital Blue */
    --bg-light: #f8fafc;     /* Slate Light background */
    --bg-white: #ffffff;     /* Card background */
    --text-dark: #0f172a;    /* Title text */
    --text-muted: #475569;   /* Body text */
}

/* Reset and Global rules */
* {
    box-sizing: border-box;
    margin: 0;
    padding: 0;
}

html {
    scroll-behavior: smooth;
}

body {
    font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, Helvetica, Arial, sans-serif;
    background-color: var(--bg-light);
    color: var(--text-dark);
    line-height: 1.6;
}

a {
    text-decoration: none;
    color: inherit;
}

.container {
    width: 90%;
    max-width: 1100px;
    margin: 0 auto;
    padding: 0 15px;
}

/* Header & Navigation layout */
header {
    position: sticky;
    top: 0;
    background-color: var(--bg-white);
    box-shadow: 0 2px 10px rgba(0,0,0,0.06);
    z-index: 1000;
}

nav {
    display: flex;
    justify-content: space-between;
    align-items: center;
    height: 70px;
}

/* Right-aligned Oran 1 University Logo */
.nav-logo {
    display: flex;
    align-items: center;
    height: 50px;
    max-width: 150px;
}

.nav-logo img {
    max-height: 100%;
    max-width: 100%;
    object-fit: contain;
}

.nav-logo-fallback {
    display: none; /* Only displays if image fails to load */
    font-weight: 700;
    color: var(--primary-dark);
    font-size: 0.95rem;
}

.nav-links {
    display: flex;
    list-style: none;
    gap: 15px;
}

.nav-links a {
    font-size: 0.95rem;
    font-weight: 500;
    color: var(--text-muted);
    padding: 8px 12px;
    border-radius: 4px;
    transition: all 0.2s ease;
}

.nav-links a:hover, .nav-links a.active {
    color: var(--primary-dark);
    background-color: rgba(13, 148, 136, 0.08);
}

/* Mobile Menu Button */
.burger {
    display: none;
    cursor: pointer;
    flex-direction: column;
    gap: 5px;
}

.burger div {
    width: 25px;
    height: 3px;
    background-color: var(--text-dark);
    border-radius: 2px;
    transition: all 0.3s ease;
}

/* Hero Unit */
.hero {
    background: linear-gradient(135deg, #0f172a 0%, #0f766e 100%);
    color: var(--bg-white);
    padding: 80px 0 60px 0;
    text-align: center;
}

.patronage {
    display: inline-block;
    background-color: rgba(255, 255, 255, 0.15);
    padding: 6px 14px;
    border-radius: 20px;
    font-size: 0.85rem;
    text-transform: uppercase;
    letter-spacing: 1px;
    margin-bottom: 20px;
    border: 1px solid rgba(255, 255, 255, 0.2);
}

.hero h1 {
    font-size: 2rem;
    line-height: 1.3;
    margin-bottom: 20px;
    font-weight: 800;
}

.hero-meta {
    display: flex;
    justify-content: center;
    flex-wrap: wrap;
    gap: 15px;
    margin-top: 30px;
    font-size: 0.9rem;
}

.meta-item {
    display: flex;
    align-items: center;
    gap: 8px;
    background: rgba(255, 255, 255, 0.08);
    padding: 8px 16px;
    border-radius: 30px;
}

/* Layout Sections */
section {
    padding: 65px 0;
    border-bottom: 1px solid rgba(0,0,0,0.03);
}

section:nth-child(even) {
    background-color: var(--bg-white);
}

.section-title {
    text-align: center;
    margin-bottom: 40px;
    position: relative;
    padding-bottom: 15px;
    font-size: 1.7rem;
    font-weight: 700;
}

.section-title::after {
    content: "";
    position: absolute;
    bottom: 0;
    left: 50%;
    transform: translateX(-50%);
    width: 60px;
    height: 4px;
    background-color: var(--primary);
    border-radius: 2px;
}

/* About Layout */
.about-text {
    max-width: 800px;
    margin: 0 auto;
    text-align: justify;
    font-size: 1.05rem;
    color: var(--text-muted);
    background: rgba(13, 148, 136, 0.03);
    padding: 30px;
    border-left: 5px solid var(--primary);
    border-radius: 0 8px 8px 0;
}

/* Keynote Cards Layout */
.keynote-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
    gap: 30px;
    max-width: 800px;
    margin: 0 auto;
}

.keynote-card {
    display: block;
    background-color: var(--bg-white);
    border-radius: 12px;
    padding: 30px;
    text-align: center;
    box-shadow: 0 4px 15px rgba(0,0,0,0.04);
    border: 1px solid rgba(0,0,0,0.04);
    transition: transform 0.25s ease, box-shadow 0.25s ease;
}

.keynote-card:hover {
    transform: translateY(-5px);
    box-shadow: 0 8px 25px rgba(13, 148, 136, 0.15);
}

.keynote-avatar {
    width: 90px;
    height: 90px;
    border-radius: 50%;
    overflow: hidden;
    margin: 0 auto 15px auto;
    background-color: rgba(13, 148, 136, 0.08);
    display: flex;
    align-items: center;
    justify-content: center;
}

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

.keynote-avatar svg {
    width: 45px;
    height: 45px;
    color: var(--primary);
}

.keynote-card h3 {
    font-size: 1.25rem;
    color: var(--text-dark);
    margin-bottom: 5px;
}

.keynote-card .role {
    font-size: 0.85rem;
    color: var(--primary);
    font-weight: 700;
    text-transform: uppercase;
    letter-spacing: 0.5px;
    margin-bottom: 8px;
}

.keynote-card .affiliation {
    font-size: 0.9rem;
    color: var(--text-muted);
    margin-bottom: 20px;
}

.btn-profile {
    display: inline-block;
    padding: 8px 16px;
    border: 1.5px solid var(--primary);
    color: var(--primary);
    font-size: 0.85rem;
    font-weight: 600;
    border-radius: 20px;
    transition: all 0.2s ease;
}

.keynote-card:hover .btn-profile {
    background-color: var(--primary);
    color: var(--bg-white);
}

/* Single-Section Committee Layout */
.committee-container {
    display: flex;
    flex-direction: column;
    gap: 40px;
}

.committee-section {
    width: 100%;
}

.committee-subtitle {
    font-size: 1.25rem;
    color: var(--primary-dark);
    margin-bottom: 20px;
    position: relative;
    padding-bottom: 5px;
    border-bottom: 2px solid rgba(13, 148, 136, 0.1);
}

.committee-grid {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(240px, 1fr));
    gap: 15px;
}

.committee-card {
    background: var(--bg-light);
    padding: 16px 20px;
    border-radius: 8px;
    border-left: 3px solid var(--secondary);
    display: flex;
    flex-direction: column;
    justify-content: center;
}

.committee-card h4 {
    font-size: 0.95rem;
    font-weight: 600;
    color: var(--text-dark);
}

.committee-card .affiliation {
    font-size: 0.8rem;
    color: var(--primary-dark);
    margin-top: 4px;
    font-weight: 500;
}

/* Sponsors/Logos section */
.logo-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(140px, 1fr));
    gap: 20px;
    align-items: center;
    justify-items: center;
}

.logo-box {
    display: flex;
    background-color: var(--bg-white);
    border: 1px solid rgba(0,0,0,0.06);
    border-radius: 8px;
    width: 150px;
    height: 85px;
    padding: 10px;
    align-items: center;
    justify-content: center;
    box-shadow: 0 2px 5px rgba(0,0,0,0.02);
    position: relative;
    overflow: hidden;
    transition: all 0.2s ease;
}

.logo-box:hover {
    transform: scale(1.05);
    box-shadow: 0 4px 15px rgba(0,0,0,0.08);
    border-color: var(--primary);
}

.logo-box img {
    max-width: 100%;
    max-height: 100%;
    object-fit: contain;
}

/* Image fallback styling (data-label display) */
.logo-box::after {
    content: attr(data-label);
    position: absolute;
    background: var(--bg-white);
    top: 0; left: 0; width: 100%; height: 100%;
    display: flex;
    align-items: center;
    justify-content: center;
    text-align: center;
    font-size: 0.8rem;
    font-weight: 700;
    color: var(--text-muted);
    padding: 5px;
}

.logo-box.has-img::after {
    display: none;
}

/* Footer structure */
footer {
    background-color: #0f172a;
    color: #94a3b8;
    padding: 40px 0;
    text-align: center;
    font-size: 0.85rem;
}

footer p {
    margin-bottom: 10px;
}

footer a {
    color: var(--primary);
    font-weight: 500;
}

/* Responsive layout controls */
@media (max-width: 768px) {
    nav {
        flex-direction: row-reverse; /* Put logo on top-right, burger on top-left */
    }

    .nav-links {
        position: fixed;
        right: -100%;
        top: 70px;
        flex-direction: column;
        background-color: var(--bg-white);
        width: 100%;
        height: calc(100vh - 70px);
        text-align: center;
        gap: 0;
        transition: 0.3s ease;
        box-shadow: 0 10px 15px rgba(0,0,0,0.05);
    }

    .nav-links li {
        width: 100%;
        border-bottom: 1px solid rgba(0,0,0,0.02);
    }

    .nav-links a {
        display: block;
        padding: 20px;
        border-radius: 0;
    }

    .burger {
        display: flex;
    }

    .nav-active {
        right: 0;
    }

    /* Hamburger Menu Animation */
    .toggle .line1 {
        transform: rotate(-45deg) translate(-5px, 6px);
    }
    .toggle .line2 {
        opacity: 0;
    }
    .toggle .line3 {
        transform: rotate(45deg) translate(-5px, -6px);
    }

    .hero h1 {
        font-size: 1.5rem;
    }

    section {
        padding: 45px 0;
    }
}