:root {
    --glass-bg: rgba(15, 23, 42, 0.4);
    --glass-border: rgba(255, 255, 255, 0.1);
    --text-main: #f8fafc;
    --text-muted: #94a3b8;
    --accent: #38bdf8;
}
body {
    margin: 0;
    font-family: 'Segoe UI', system-ui, sans-serif;
    background-color: #020617;
    background-image: url('../assets/bg/bg1.jpg');
    background-size: cover;
    background-position: center;
    background-attachment: fixed;
    color: var(--text-main);
    line-height: 1.6;
    transition: background-image 1.5s ease-in-out;
}
.overlay {
    position: fixed;
    top: 0; left: 0; width: 100%; height: 100%;
    background: linear-gradient(135deg, rgba(2,6,23,0.8) 0%, rgba(15,23,42,0.4) 100%);
    z-index: -1;
}
header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 20px 5%;
    background: rgba(15, 23, 42, 0.6);
    backdrop-filter: blur(16px);
    -webkit-backdrop-filter: blur(16px);
    border-bottom: 1px solid var(--glass-border);
    position: sticky;
    top: 0;
    z-index: 100;
}
.logo {
    font-size: 1.5rem;
    font-weight: 900;
    letter-spacing: 3px;
    color: var(--text-main);
    text-decoration: none;
    display: flex;
    align-items: center;
    gap: 12px;
}
.logo svg { width: 32px; height: 32px; fill: var(--accent); }
.nav-links a {
    color: var(--text-muted);
    text-decoration: none;
    margin-left: 25px;
    font-size: 0.85rem;
    text-transform: uppercase;
    letter-spacing: 1px;
    font-weight: bold;
    transition: color 0.3s;
}
.nav-links a:hover { color: var(--accent); }

.container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 60px 5%;
}

.hero-glass {
    background: var(--glass-bg);
    backdrop-filter: blur(20px);
    -webkit-backdrop-filter: blur(20px);
    border: 1px solid var(--glass-border);
    border-radius: 24px;
    padding: 80px 40px;
    text-align: center;
    box-shadow: 0 25px 50px -12px rgba(0, 0, 0, 0.5);
    margin-bottom: 60px;
    position: relative;
    overflow: hidden;
}
.hero-glass h1 { font-size: clamp(2.5rem, 5vw, 4rem); margin: 0 0 20px 0; font-weight: 900; background: linear-gradient(to right, #38bdf8, #818cf8); -webkit-background-clip: text; -webkit-text-fill-color: transparent; }
.hero-glass p { font-size: 1.2rem; color: var(--text-muted); max-width: 700px; margin: 0 auto; }

.grid-2 {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(320px, 1fr));
    gap: 30px;
    margin-bottom: 60px;
}

.glass-panel {
    background: var(--glass-bg);
    backdrop-filter: blur(16px);
    border: 1px solid var(--glass-border);
    border-radius: 16px;
    padding: 40px;
    transition: all 0.4s ease;
}
.glass-panel:hover { transform: translateY(-5px); border-color: rgba(56, 189, 248, 0.5); box-shadow: 0 10px 30px -10px rgba(56, 189, 248, 0.2); }
.glass-panel h2 { margin-top: 0; font-size: 1.4rem; border-bottom: 1px solid var(--glass-border); padding-bottom: 15px; display: flex; align-items: center; gap: 12px;}
.glass-panel h2 svg { width: 28px; height: 28px; stroke: var(--accent); fill: none; }

#audio-controls, #focus-timer {
    min-height: 150px;
    display: flex;
    flex-direction: column;
    justify-content: center;
    align-items: center;
    text-align: center;
}

.article-grid {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(280px, 1fr));
    gap: 20px;
}
.article-card {
    background: rgba(15, 23, 42, 0.7);
    border: 1px solid var(--glass-border);
    border-radius: 12px;
    padding: 25px;
    text-decoration: none;
    color: var(--text-main);
    transition: all 0.3s ease;
}
.article-card:hover {
    background: rgba(30, 41, 59, 0.9);
    border-color: var(--accent);
}
.article-card h3 { margin: 0 0 10px 0; font-size: 1.1rem; }
.article-card p { margin: 0; font-size: 0.9rem; color: var(--text-muted); }

footer {
    text-align: center;
    padding: 40px;
    border-top: 1px solid var(--glass-border);
    color: var(--text-muted);
    font-size: 0.9rem;
    background: rgba(2, 6, 23, 0.9);
}