/* General Reset */
body {
    margin: 0;
    font-family: 'Arial', sans-serif;
    line-height: 1.6;
}

/* Navbar */
.navbar {
    background-color: #333; /* رنگ پس‌زمینه تیره */
    color: #fff; /* رنگ متن سفید */
    padding: 10px 20px;
}
.navbar .navbar-brand, .navbar .nav-link {
    color: #fff; /* متن سفید */
    text-decoration: none;
    font-weight: bold;
    transition: color 0.3s ease;
}
.navbar .nav-link:hover {
    color: #f0a500; /* تغییر رنگ هنگام هاور */
}
.navbar-toggler {
    border-color: #fff; /* دکمه ناوبری برای موبایل */
}
.navbar-toggler-icon {
    background-image: url("data:image/svg+xml;charset=utf8,%3Csvg xmlns='http://www.w3.org/2000/svg' viewBox='0 0 30 30'%3E%3Cpath stroke='rgba(255,255,255,1)' stroke-width='2' d='M4 7h22M4 15h22M4 23h22'/%3E%3C/svg%3E");
}


/* Header */
header {
    background: linear-gradient(135deg, #1a237e, #0d47a1, #42a5f5);
    background-size: 300% 300%;
    animation: gradientAnimation 6s ease infinite;
    color: white;
    text-align: center;
    padding: 50px 0;
    box-shadow: 0 10px 15px rgba(0, 0, 0, 0.4);
}

@keyframes gradientAnimation {
    0% { background-position: 0% 50%; }
    50% { background-position: 100% 50%; }
    100% { background-position: 0% 50%; }
}

header h1 {
    font-size: 3rem;
    font-weight: bold;
    background: linear-gradient(135deg, #42a5f5, #1e88e5);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    text-shadow: 1px 1px 2px rgba(0, 0, 0, 0.5);
    transition: all 0.3s ease; /* انیمیشن تغییر رنگ */
}

header h1:hover {
    background: none; /* حذف گرادینت هنگام هاور */
    -webkit-text-fill-color: white; /* ثابت شدن رنگ سفید */
    text-shadow: 1px 1px 5px rgba(0, 0, 0, 0.7); /* افزایش سایه */
}



/* Footer */
footer {
    background: #333;
    color: #fff;
    text-align: center;
    padding: 10px 0;
    position: relative;
    bottom: 0;
    width: 100%;
}

/* Main Sections */
main {
    padding: 20px;
}

/* Cards */
.card {
    border: 1px solid #ddd;
    border-radius: 8px;
    box-shadow: 0 4px 6px rgba(0, 0, 0, 0.1);
}
.card img {
    border-top-left-radius: 8px;
    border-top-right-radius: 8px;
}
.card-body {
    padding: 15px;
}

/* Buttons */
.btn {
    background-color: #333;
    color: #fff;
    border: none;
    padding: 10px 20px;
    text-transform: uppercase;
    cursor: pointer;
    transition: background-color 0.3s;
}
.btn:hover {
    background-color: #f0a500;
}

/* Lists */
ul {
    list-style: none;
    padding: 0;
}
ul li {
    margin-bottom: 10px;
}
.parallax {
    background-image: url('https://cdn.britannica.com/84/203584-131-357FBE7D/speed-internet-technology-background.jpg'); /* تصویر مورد نظر */
    background-attachment: fixed;
    background-position: center;
    background-repeat: no-repeat;
    background-size: cover;
    height: 400px;
    display: flex;
    justify-content: center;
    align-items: center;
    color: white;
    font-size: 2rem;
    font-weight: bold;
    text-shadow: 0 2px 5px rgba(0, 0, 0, 0.7);
}
/* استایل عکس پروفایل */
.profile-pic {
    display: block;
    margin: 0 auto;
    width: 150px;
    border-radius: 50%;
    transition: opacity 0.3s ease;
}

.profile-pic:hover {
    opacity: 0.7;
}


/* هدر با افکت پارالاکس */
.publications-header {
    background: url('https://source.unsplash.com/1600x900/?research,technology') center/cover fixed;
    height: 250px;
    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: center;
    text-align: center;
    color: white;
    text-shadow: 2px 2px 10px rgba(0, 0, 0, 0.7);
}

.publications-header h1 {
    font-size: 36px;
    font-weight: bold;
}

/* طراحی کارت مقالات */
.publication-container {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(350px, 1fr));
    gap: 20px;
    padding: 20px;
    max-width: 1100px;
    margin: auto;
}

.publication-card {
    background: rgba(255, 255, 255, 0.9);
    border-radius: 12px;
    box-shadow: 0 5px 15px rgba(0, 0, 0, 0.2);
    padding: 20px;
    text-align: left;
    transition: transform 0.3s ease, box-shadow 0.3s ease;
}

.publication-card.alt {
    background: linear-gradient(135deg, #e3f2fd, #bbdefb);
}

.publication-card h2 {
    font-size: 18px;
    color: #0d47a1;
    margin-bottom: 10px;
}

.publication-card p {
    color: #444;
    font-size: 14px;
}

.publication-card:hover {
    transform: translateY(-5px);
    box-shadow: 0 10px 20px rgba(0, 0, 0, 0.3);
}

/* دکمه لینک مقاله */
.btn {
    display: inline-block;
    margin-top: 10px;
    padding: 8px 16px;
    background: #0d47a1;
    color: white;
    text-decoration: none;
    font-weight: bold;
    border-radius: 5px;
    transition: background 0.3s;
}

.btn:hover {
    background: #1565c0;
}

/* ===== GLOBAL DARK FIX ===== */
body {
    background: #0b0f1a;
    color: #e6e9f0;
}

/* ===== TIMELINE SECTION ===== */
.timeline-section {
    padding: 80px 8%;
    background: linear-gradient(180deg, #0b0f1a, #0e1324);
}

.timeline-title {
    text-align: center;
    font-size: 2.6rem;
    margin-bottom: 70px;
    font-weight: 700;
    background: linear-gradient(90deg, #4facfe, #ffffff, #4facfe);
    background-size: 300%;
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    animation: titleGlow 6s infinite linear;
}

@keyframes titleGlow {
    0% { background-position: 0%; }
    100% { background-position: 300%; }
}

/* ===== TIMELINE CORE ===== */
.timeline {
    position: relative;
    max-width: 900px;
    margin: auto;
}

.timeline::before {
    content: "";
    position: absolute;
    left: 50%;
    top: 0;
    width: 3px;
    height: 100%;
    background: rgba(79, 172, 254, 0.25);
    transform: translateX(-50%);
}

/* ===== TIMELINE ITEM ===== */
.timeline-item {
    position: relative;
    margin-bottom: 80px;
    opacity: 0;
    transform: translateY(40px);
    transition: all 0.9s ease;
}

.timeline-item.show {
    opacity: 1;
    transform: translateY(0);
}

.timeline-year {
    position: absolute;
    left: 50%;
    top: -35px;
    transform: translateX(-50%);
    background: #11162a;
    color: #4facfe;
    padding: 6px 16px;
    border-radius: 30px;
    font-weight: 600;
    font-size: 0.9rem;
    box-shadow: 0 0 20px rgba(79,172,254,0.35);
}

/* ===== TIMELINE CARD ===== */
.timeline-card {
    width: 46%;
    background: rgba(17, 22, 42, 0.85);
    padding: 26px;
    border-radius: 18px;
    box-shadow: 0 25px 60px rgba(0,0,0,0.6);
    backdrop-filter: blur(10px);
    transition: transform 0.4s ease, box-shadow 0.4s ease;
}

.timeline-item:nth-child(odd) .timeline-card {
    margin-left: auto;
}

.timeline-card:hover {
    transform: translateY(-8px) scale(1.02);
    box-shadow: 0 35px 80px rgba(79,172,254,0.35);
}

.timeline-card h3 {
    font-size: 1.2rem;
    color: #ffffff;
    margin-bottom: 10px;
}

.timeline-card p {
    font-size: 0.95rem;
    opacity: 0.85;
}

/* ===== BUTTON ===== */
.timeline-card .btn {
    margin-top: 12px;
    background: linear-gradient(135deg, #4facfe, #00f2fe);
    color: #000;
    border-radius: 30px;
    padding: 8px 18px;
    font-weight: 600;
}