/* ==========================================
   গ্লোবাল রিসেট এবং ভ্যারিয়েবল
   ========================================== */
:root {
    --primary-blue: #0A3C7E;
    --navy-dark: #072652;
    --accent-orange: #F2994A;
    --accent-yellow: #F2C94C;
    --bg-light: #F8FAFC;
    --text-color: #2D3748;
    --text-muted: #64748B;
    --white: #ffffff;
    --border-radius: 16px;
}

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

body {
    font-family: 'Noto Sans Bengali', sans-serif;
    background-color: var(--bg-light);
    color: var(--text-color);
    overflow-x: hidden;
}

.container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 20px;
}

a {
    text-decoration: none;
    transition: all 0.3s ease;
}

ul {
    list-style: none;
}

/* ==========================================
   বাটন স্টাইল
   ========================================== */
.btn {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    padding: 12px 28px;
    border-radius: 8px;
    font-weight: 600;
    font-size: 15px;
    cursor: pointer;
    text-align: center;
    box-shadow: 0 4px 12px rgba(0, 0, 0, 0.08);
}

.btn-navy {
    background-color: var(--primary-blue);
    color: var(--white);
}

.btn-navy:hover {
    background-color: var(--navy-dark);
    transform: translateY(-2px);
    box-shadow: 0 6px 16px rgba(10, 60, 126, 0.25);
}

.btn-outline {
    border: 2px solid var(--white);
    color: var(--navy-dark);
    background: rgba(255, 255, 255, 0.95);
    backdrop-filter: blur(4px);
}

.btn-outline:hover {
    background-color: var(--navy-dark);
    color: var(--white);
    border-color: var(--navy-dark);
    transform: translateY(-2px);
}

/* ==========================================
   ১০০% রেসপন্সিভ হিরো সেকশন
   ========================================== */
.hero {
    position: relative;
    width: 100%;
    /* ডেস্কটপে ছবির আসল রেশিও বজায় রাখতে aspect-ratio ব্যবহার করা হয়েছে */
    aspect-ratio: 21 / 9;
    min-height: 380px;
    max-height: 560px;
    overflow: hidden;
    display: flex;
    align-items: flex-end;
}

.hero-bg-img {
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    object-fit: cover;
    object-position: top center;
    z-index: 0;
}

.hero-container {
    position: absolute;
    bottom: 40px;
    left: 50%;
    transform: translateX(-50%);
    z-index: 2;
    width: 100%;
    display: flex;
    justify-content: center;
    padding: 0 20px;
}

.hero-btns {
    display: flex;
    align-items: center;
    justify-content: center;
    gap: 15px;
}

.hero-btns .btn {
    min-width: 160px;
    text-align: center;
}

.hero-wave {
    position: absolute;
    bottom: -1px;
    left: 0;
    width: 100%;
    line-height: 0;
    z-index: 3;
}

.hero-wave svg {
    width: 100%;
    height: auto;
}

/* ==========================================
   ৪টি ইনফো কার্ড সেকশন
   ========================================== */
.info-cards-section {
    margin-top: -30px;
    position: relative;
    z-index: 10;
    margin-bottom: 70px;
}

.info-cards-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(240px, 1fr));
    gap: 20px;
}

.info-card {
    background: var(--white);
    padding: 24px;
    border-radius: var(--border-radius);
    display: flex;
    align-items: flex-start;
    gap: 15px;
    box-shadow: 0 10px 25px rgba(0, 0, 0, 0.04);
    transition: all 0.3s ease;
    border: 1.5px solid #E2E8F0;
}

.info-card:nth-child(1) { border-bottom: 4px solid #3B82F6; }
.info-card:nth-child(2) { border-bottom: 4px solid #F97316; }
.info-card:nth-child(3) { border-bottom: 4px solid #072652; }
.info-card:nth-child(4) { border-bottom: 4px solid #EAB308; }

.info-card:hover {
    transform: translateY(-6px);
    box-shadow: 0 15px 30px rgba(0, 0, 0, 0.08);
}

.icon-box {
    width: 52px;
    height: 52px;
    border-radius: 12px;
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 22px;
    flex-shrink: 0;
}

.icon-blue { background-color: #EFF6FF; color: #2563EB; }
.icon-orange { background-color: #FFF7ED; color: #EA580C; }
.icon-navy { background-color: #F0F3F9; color: var(--navy-dark); }
.icon-gold { background-color: #FEFCE8; color: #CA8A04; }

.info-text h3 {
    font-size: 18px;
    color: var(--navy-dark);
    margin-bottom: 6px;
    font-weight: 700;
}

.info-text p {
    font-size: 13.5px;
    color: var(--text-muted);
    line-height: 1.5;
}

/* ==========================================
   আমাদের সম্পর্কে সেকশন
   ========================================== */
.about-section {
    padding: 40px 0 80px 0;
}

.about-container {
    display: flex;
    align-items: center;
    gap: 50px;
    background: var(--white);
    padding: 40px;
    border-radius: 24px;
    border: 1px solid #E2E8F0;
    box-shadow: 0 10px 30px rgba(0,0,0,0.03);
}

.about-content {
    flex: 1;
}

.section-tag {
    color: #EA580C;
    background: #FFF7ED;
    padding: 4px 14px;
    border-radius: 20px;
    font-size: 14px;
    font-weight: 700;
    display: inline-block;
    margin-bottom: 12px;
    border: 1px solid #FFEDD5;
}

.about-content h2 {
    font-size: 34px;
    color: var(--navy-dark);
    margin-bottom: 18px;
    line-height: 1.3;
}

.about-content p {
    color: var(--text-muted);
    font-size: 16px;
    margin-bottom: 25px;
    line-height: 1.7;
}

.about-image {
    flex: 1;
    width: 100%;
    border-radius: 16px;
    overflow: hidden;
    box-shadow: 0 12px 24px rgba(0,0,0,0.1);
}

.about-image img {
    width: 100%;
    height: auto;
    max-height: 400px;
    object-fit: cover;
    display: block;
}

/* ==========================================
   একাডেমিক প্রোগ্রামসমূহ
   ========================================== */
.academic-section {
    padding: 60px 0 90px 0;
}

.section-header {
    text-align: center;
    margin-bottom: 50px;
}

.section-header h2 {
    font-size: 34px;
    color: var(--navy-dark);
}

.academic-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(260px, 1fr));
    gap: 25px;
}

.academic-card {
    background: var(--white);
    padding: 28px 24px;
    border-radius: var(--border-radius);
    border: 1px solid #E2E8F0;
    transition: all 0.3s ease;
}

.academic-card:hover {
    transform: translateY(-5px);
    border-color: var(--primary-blue);
    box-shadow: 0 15px 30px rgba(10, 60, 126, 0.1);
}

.acad-header {
    display: flex;
    align-items: center;
    gap: 15px;
    margin-bottom: 15px;
}

.acad-icon {
    width: 48px;
    height: 48px;
    border-radius: 12px;
    background: linear-gradient(135deg, var(--primary-blue), var(--navy-dark));
    color: var(--white);
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 20px;
    flex-shrink: 0;
    box-shadow: 0 6px 12px rgba(10, 60, 126, 0.2);
}

.academic-card h3 {
    font-size: 18px;
    color: var(--navy-dark);
    font-weight: 700;
    margin-bottom: 0;
    line-height: 1.3;
}

.academic-card p {
    font-size: 14px;
    color: var(--text-muted);
    line-height: 1.6;
}

/* ==========================================
   রেসপন্সিভ মিডিয়া কোয়েরি
   ========================================== */

/* ট্যাবলেট ও মাঝারি স্ক্রিন */
@media (max-width: 992px) {
    .hero {
        aspect-ratio: 16 / 8;
        min-height: 320px;
    }

    .about-container {
        flex-direction: column;
        padding: 30px 20px;
    }

    .about-image img {
        max-height: 320px;
    }
}

/* ছোট ট্যাবলেট ও মোবাইল */
@media (max-width: 768px) {
    .hero {
        aspect-ratio: 16 / 9;
        min-height: 260px;
    }

    .hero-container {
        bottom: 20px;
        padding: 0 15px;
    }

    .hero-btns {
        width: 100%;
        max-width: 320px;
        gap: 10px;
    }

    .hero-btns .btn {
        flex: 1;
        min-width: auto;
        padding: 8px 12px;
        font-size: 13.5px;
    }

    .info-cards-section {
        margin-top: -15px;
    }

    .about-content h2, 
    .section-header h2 {
        font-size: 26px;
    }
}

/* খুব ছোট মোবাইল স্ক্রিন */
@media (max-width: 480px) {
    .hero {
        min-height: 230px;
    }

    .hero-container {
        bottom: 14px;
    }

    .hero-btns .btn {
        padding: 7px 8px;
        font-size: 12px;
        white-space: nowrap;
    }
}