/* Modern Dark Theme */
:root {
    --bg-primary: #0f0f0f;
    --bg-secondary: #1a1a1a;
    --bg-tertiary: #252525;
    --bg-hover: #2d2d2d;
    --text-primary: #ffffff;
    --text-secondary: #a0a0a0;
    --accent: #6366f1;
    --accent-hover: #818cf8;
    --accent-glow: rgba(99, 102, 241, 0.3);
    --border: #333333;
    --shadow: rgba(0, 0, 0, 0.5);
    --success: #22c55e;
    --error: #ef4444;
}

* {
    box-sizing: border-box;
}

body {
    font-family: 'Segoe UI', -apple-system, BlinkMacSystemFont, sans-serif;
    margin: 0;
    padding: 0;
    background-color: var(--bg-primary);
    color: var(--text-primary);
    line-height: 1.6;
}

/* Login Container */
.login-container {
    display: flex;
    justify-content: center;
    align-items: center;
    height: 100vh;
    background: linear-gradient(135deg, var(--bg-primary) 0%, #1a1a2e 100%);
}

.login-form {
    background: var(--bg-secondary);
    padding: 40px;
    border-radius: 16px;
    box-shadow: 0 25px 50px -12px var(--shadow),
                0 0 0 1px var(--border);
    width: 360px;
    backdrop-filter: blur(10px);
}

.login-form h2 {
    margin: 0 0 30px 0;
    text-align: center;
    font-weight: 600;
    font-size: 1.75rem;
    background: linear-gradient(135deg, var(--text-primary), var(--accent));
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
}

.login-form input {
    width: 100%;
    padding: 14px 16px;
    margin: 8px 0;
    border: 1px solid var(--border);
    border-radius: 10px;
    background-color: var(--bg-tertiary);
    color: var(--text-primary);
    font-size: 1rem;
    transition: all 0.2s ease;
}

.login-form input:focus {
    outline: none;
    border-color: var(--accent);
    box-shadow: 0 0 0 3px var(--accent-glow);
}

.login-form input::placeholder {
    color: var(--text-secondary);
}

.login-form button {
    width: 100%;
    padding: 14px;
    margin-top: 20px;
    background: linear-gradient(135deg, var(--accent), #8b5cf6);
    color: white;
    border: none;
    border-radius: 10px;
    cursor: pointer;
    font-size: 1rem;
    font-weight: 600;
    transition: all 0.3s ease;
    box-shadow: 0 4px 15px var(--accent-glow);
}

.login-form button:hover {
    transform: translateY(-2px);
    box-shadow: 0 8px 25px var(--accent-glow);
}

.login-form button:active {
    transform: translateY(0);
}

/* App Container */
.app-container {
    display: none;
    padding: 30px;
    max-width: 1400px;
    margin: 0 auto;
    min-height: 100vh;
}

/* Tabs */
.tabs {
    display: flex;
    border-bottom: 2px solid var(--border);
    margin-bottom: 30px;
    gap: 4px;
    overflow-x: auto;
    padding-bottom: 2px;
}

.tab {
    padding: 14px 24px;
    cursor: pointer;
    background-color: transparent;
    border: none;
    border-radius: 10px 10px 0 0;
    color: var(--text-secondary);
    font-size: 0.95rem;
    font-weight: 500;
    transition: all 0.2s ease;
    white-space: nowrap;
    position: relative;
}

.tab:hover {
    background-color: var(--bg-hover);
    color: var(--text-primary);
}

.tab.active {
    background-color: var(--bg-secondary);
    color: var(--accent);
    border: 1px solid var(--border);
    border-bottom: 1px solid var(--bg-secondary);
    margin-bottom: -2px;
}

.tab.active::after {
    content: '';
    position: absolute;
    bottom: 0;
    left: 50%;
    transform: translateX(-50%);
    width: 40%;
    height: 2px;
    background: var(--accent);
    border-radius: 2px;
}

/* Tab Content */
.tab-content {
    display: none;
    padding: 30px;
    border: 1px solid var(--border);
    border-radius: 12px;
    background-color: var(--bg-secondary);
    box-shadow: 0 4px 20px var(--shadow);
}

.tab-content.active {
    display: block;
    animation: fadeIn 0.3s ease;
}

@keyframes fadeIn {
    from {
        opacity: 0;
        transform: translateY(10px);
    }
    to {
        opacity: 1;
        transform: translateY(0);
    }
}

/* Buttons Container */
.buttons-container {
    display: flex;
    flex-wrap: wrap;
    gap: 12px;
}

.menu-button {
    padding: 12px 20px;
    background: linear-gradient(135deg, var(--bg-tertiary), var(--bg-hover));
    color: var(--text-primary);
    border: 1px solid var(--border);
    border-radius: 10px;
    cursor: pointer;
    text-decoration: none;
    font-size: 0.95rem;
    font-weight: 500;
    transition: all 0.2s ease;
    display: inline-flex;
    align-items: center;
    gap: 8px;
}

.menu-button:hover {
    background: linear-gradient(135deg, var(--accent), #8b5cf6);
    border-color: var(--accent);
    transform: translateY(-2px);
    box-shadow: 0 4px 15px var(--accent-glow);
}

.menu-button:active {
    transform: translateY(0);
}

/* Scrollbar Styling */
::-webkit-scrollbar {
    width: 8px;
    height: 8px;
}

::-webkit-scrollbar-track {
    background: var(--bg-primary);
}

::-webkit-scrollbar-thumb {
    background: var(--border);
    border-radius: 4px;
}

::-webkit-scrollbar-thumb:hover {
    background: var(--text-secondary);
}

/* Selection */
::selection {
    background: var(--accent);
    color: white;
}

/* Responsive */
@media (max-width: 768px) {
    .login-form {
        width: 90%;
        max-width: 360px;
        padding: 30px;
    }
    
    .app-container {
        padding: 15px;
    }
    
    .tabs {
        flex-wrap: nowrap;
        overflow-x: auto;
    }
    
    .tab {
        padding: 12px 18px;
        font-size: 0.9rem;
    }
    
    .tab-content {
        padding: 20px;
    }
}