/* ======================== IMPORT COLOR SCHEME ======================== */
@import url('color-scheme.css');

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

html,
body {
    height: 100%;
    font-family: 'Roboto', -apple-system, BlinkMacSystemFont, 'Segoe UI', sans-serif;
}

/* ======================== HEADER ======================== */
header {
    width: 100%;
    height: 10vh;
    background: #1e293b !important;
    background: linear-gradient(135deg, #1e293b 0%, #334155 50%, #475569 100%) !important;
    display: flex;
    align-items: center;
    /* Căn giữa theo chiều dọc */
    justify-content: space-between;
    /* Chia đều 3 phần: trái - giữa - phải */
    padding: 0 2rem;
    box-shadow: 0 4px 20px rgba(30, 41, 59, 0.15);
    position: sticky;
    top: 0;
    z-index: 1000;
    border-bottom: 1px solid rgba(255, 255, 255, 0.1);
}

/* Navigation bên trái */
.nav-left {
    flex: 1;
    /* Chiếm 1 phần không gian */
    display: flex;
    justify-content: flex-start;
    /* Căn trái */
    gap: 1.5rem;
    align-items: center;
}

.nav-left a {
    color: var(--secondary-color);
    text-decoration: none;
    font-weight: 500;
    padding: 0.6rem 1.2rem;
    border-radius: 8px;
    transition: all 0.3s ease;
    background-color: transparent;
    min-width: 100px;
    text-align: center;
    white-space: nowrap;
    display: inline-flex;
    align-items: center;
    justify-content: center;
}

.nav-left a:hover {
    background-color: rgba(255, 255, 255, 0.1);
    color: var(--secondary-color);
    transform: translateY(-1px);
    box-shadow: 0 2px 8px rgba(255, 255, 255, 0.2);
}
/* Logo ở giữa */
.logo {
    flex: 1;
    /* Chiếm 1 phần không gian */
    display: flex;
    justify-content: center;
    /* Căn giữa */
}

/* Navigation bên phải */
.nav-right {
    flex: 1;
    /* Chiếm 1 phần không gian */
    display: flex;
    justify-content: flex-end;
    /* Căn phải */
    gap: 1rem;
    /* Khoảng cách giữa các link */
}
.nav-right a {
    color: var(--secondary-color);
    text-decoration: none;
    font-weight: 500;
    padding: 0.5rem 0;
    position: relative;
    transition: all 0.3s ease;
}

.nav-right a::after {
    content: '';
    position: absolute;
    bottom: 0;
    left: 0;
    width: 0;
    height: 2px;
    background-color: var(--secondary-color);
    transition: width 0.3s ease;
}

.nav-right a:hover::after {
    width: 100%;
}

/* Style cho logo */
header img {
    height: 8vh;
    width: auto;
    border-radius: 50%;
    transition: all 0.3s ease;
    cursor: pointer;
}

header img:hover {
    transform: scale(1.1) rotate(5deg);
    box-shadow: 0 4px 15px rgba(255, 255, 255, 0.3);
    filter: brightness(1.1);
}

/* ======================== BODY ======================== */
body {
    background-color: var(--background-color);
    color: var(--text-primary);
    font-size: 16px;
    /* Cỡ chữ cơ bản */

    min-height: 100vh;
}

/* ======================== FOOTER ======================== */
footer {
    width: 100%;
    background: #1e293b;
    background: linear-gradient(135deg, #1e293b 0%, #334155 50%, #475569 100%);
    color: var(--secondary-color);
    padding: 3rem 0 2rem 0;
    margin-top: auto;
    border-top: 1px solid rgba(255, 255, 255, 0.1);
}

.frow {
    width: 90%;
    max-width: 1200px;
    margin: 0 auto;
    display: flex;
    justify-content: space-between;
    align-items: flex-start;
    gap: 2rem;
    flex-wrap: wrap;
}

.fcol {
    flex: 1;
    min-width: 250px;
    padding: 0 1rem;
}

.fcol h3 {
    color: var(--secondary-color);
    margin-bottom: 1rem;
    font-size: 1.1rem;
    font-weight: 600;
}

.fcol p {
    margin-bottom: 0.8rem;
    line-height: 1.5;
    color: var(--secondary-color);
}

.fcol a {
    color: var(--accent-color);
    text-decoration: none;
    transition: all 0.3s ease;
    position: relative;
    display: inline-block;
}

.fcol a::after {
    content: '';
    position: absolute;
    bottom: 0;
    left: 0;
    width: 0;
    height: 2px;
    background-color: var(--accent-color);
    transition: width 0.3s ease;
}

.fcol a:hover::after {
    width: 100%;
}

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

.fcol ul {
    list-style: none;
    padding: 0;
}

.fcol ul li {
    margin-bottom: 0.8rem;
}

.fcol ul li a {
    color: var(--secondary-color);
    text-decoration: none;
    transition: all 0.3s ease;
    padding: 0.3rem 0;
    display: inline-block;
    position: relative;
}

.fcol ul li a::after {
    content: '';
    position: absolute;
    bottom: 0;
    left: 0;
    width: 0;
    height: 2px;
    background-color: var(--accent-color);
    transition: width 0.3s ease;
}

.fcol ul li a:hover {
    color: var(--accent-color);
    transform: translateX(5px);
}

.fcol ul li a:hover::after {
    width: 100%;
}

.fcol iframe {
    border-radius: 8px;
    margin-bottom: 1rem;
}

/* ======================== RESPONSIVE MOBILE ======================== */
@media (max-width: 768px) {
    .frow {
        flex-direction: column;
        text-align: center;
    }
    
    .fcol {
        min-width: 100%;
        margin-bottom: 2rem;
    }
    
    .fcol iframe {
        width: 100%;
        max-width: 300px;
    }
    
    header {
        padding: 0 1rem;
        height: auto;
        min-height: 10vh;
        flex-wrap: wrap;
    }
    
    .nav-left {
        gap: 0.8rem;
        flex-wrap: wrap;
        justify-content: center;
    }
    
    .nav-left a {
        min-width: 80px !important;
        padding: 0.5rem 0.8rem !important;
        font-size: 0.9rem !important;
    }
    
    .logo {
        order: -1;
        flex: 100%;
        margin-bottom: 0.5rem;
    }
    
    .nav-right {
        gap: 0.8rem;
        justify-content: center;
    }
}