/* ====================================
   Variables CSS
   ==================================== */
:root {
    --primary-color: #4a90e2;
    --primary-hover: #357abd;
    --secondary-color: #6c757d;
    --success-color: #28a745;
    --error-color: #dc3545;
    --warning-color: #ffc107;
    --bg-color: #f5f7fa;
    --card-bg: #ffffff;
    --text-color: #333333;
    --text-muted: #6c757d;
    --border-color: #dee2e6;
    --shadow: 0 2px 4px rgba(0,0,0,0.1);
    --shadow-lg: 0 4px 12px rgba(0,0,0,0.15);
    --border-radius: 8px;
    --transition: all 0.3s ease;
}

/* ====================================
   Reset & Base
   ==================================== */
* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

body {
    font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, "Helvetica Neue", Arial, sans-serif;
    background-color: var(--bg-color);
    color: var(--text-color);
    line-height: 1.6;
    font-size: 16px;
}

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

/* ====================================
   Header
   ==================================== */
.main-header {
    background: var(--card-bg);
    border-bottom: 1px solid var(--border-color);
    padding: 1rem 0;
    box-shadow: var(--shadow);
}

.header-content {
    display: flex;
    justify-content: space-between;
    align-items: center;
    gap: 1rem;
}

.logo {
    font-size: 1.5rem;
    font-weight: 700;
    color: var(--primary-color);
}

.main-nav {
    display: flex;
    align-items: center;
    gap: 1rem;
}

.user-info {
    color: var(--text-muted);
    font-size: 0.9rem;
}

/* ====================================
   Main Content
   ==================================== */
.main-content {
    padding: 2rem 0;
    min-height: calc(100vh - 180px);
}

.welcome-section {
    text-align: center;
    margin-bottom: 3rem;
}

.welcome-section h2 {
    font-size: 2rem;
    margin-bottom: 0.5rem;
    color: var(--text-color);
}

.welcome-section p {
    color: var(--text-muted);
    font-size: 1.1rem;
}

/* ====================================
   Tools Section
   ==================================== */
.tools-section {
    margin-bottom: 2rem;
}

.section-header {
    margin-bottom: 2rem;
}

.section-header h3 {
    font-size: 1.5rem;
    margin-bottom: 0.5rem;
}

.tools-grid {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(250px, 1fr));
    gap: 1.5rem;
    margin-bottom: 2rem;
}

.tool-card {
    background: var(--card-bg);
    border: 1px solid var(--border-color);
    border-radius: var(--border-radius);
    padding: 2rem 1.5rem;
    text-align: center;
    text-decoration: none;
    color: var(--text-color);
    transition: var(--transition);
    box-shadow: var(--shadow);
}

.tool-card:hover {
    transform: translateY(-4px);
    box-shadow: var(--shadow-lg);
    border-color: var(--primary-color);
}

.tool-icon {
    font-size: 3rem;
    margin-bottom: 1rem;
}

.tool-name {
    font-size: 1.2rem;
    margin-bottom: 0.5rem;
    color: var(--text-color);
}

.tool-description {
    font-size: 0.9rem;
    color: var(--text-muted);
}

/* ====================================
   Empty State
   ==================================== */
.empty-state {
    text-align: center;
    padding: 3rem 1rem;
    background: var(--card-bg);
    border-radius: var(--border-radius);
    border: 2px dashed var(--border-color);
}

.empty-icon {
    font-size: 4rem;
    margin-bottom: 1rem;
    opacity: 0.5;
}

.empty-state h4 {
    font-size: 1.3rem;
    margin-bottom: 0.5rem;
}

.empty-state p {
    color: var(--text-muted);
    margin-bottom: 0.5rem;
}

/* ====================================
   Info Section
   ==================================== */
.info-section {
    margin-top: 3rem;
}

.info-box {
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    color: white;
    padding: 2rem;
    border-radius: var(--border-radius);
    box-shadow: var(--shadow-lg);
}

.info-box h4 {
    margin-bottom: 1rem;
    font-size: 1.2rem;
}

.info-box ol {
    margin-left: 1.5rem;
}

.info-box li {
    margin-bottom: 0.5rem;
}

.info-box code {
    background: rgba(255,255,255,0.2);
    padding: 0.2rem 0.4rem;
    border-radius: 4px;
    font-size: 0.9rem;
}

/* ====================================
   Footer
   ==================================== */
.main-footer {
    background: var(--card-bg);
    border-top: 1px solid var(--border-color);
    padding: 1.5rem 0;
    text-align: center;
    color: var(--text-muted);
    font-size: 0.9rem;
}

/* ====================================
   Login Page
   ==================================== */
.login-page {
    display: flex;
    align-items: center;
    justify-content: center;
    min-height: 100vh;
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
}

.login-container {
    width: 100%;
    max-width: 420px;
    padding: 0 20px;
}

.login-box {
    background: var(--card-bg);
    border-radius: var(--border-radius);
    padding: 2.5rem;
    box-shadow: var(--shadow-lg);
}

.login-header {
    text-align: center;
    margin-bottom: 2rem;
}

.login-header h1 {
    font-size: 2.5rem;
    margin-bottom: 0.5rem;
    color: var(--primary-color);
}

.login-header p {
    color: var(--text-muted);
}

.login-form {
    margin-bottom: 1.5rem;
}

.login-footer {
    text-align: center;
    padding-top: 1.5rem;
    border-top: 1px solid var(--border-color);
}

.login-footer .text-muted {
    font-size: 0.85rem;
}

/* ====================================
   Forms
   ==================================== */
.form-group {
    margin-bottom: 1.5rem;
}

.form-group label {
    display: block;
    margin-bottom: 0.5rem;
    font-weight: 500;
    color: var(--text-color);
}

.form-group input[type="text"],
.form-group input[type="password"],
.form-group input[type="email"],
.form-group textarea,
.form-group select {
    width: 100%;
    padding: 0.75rem 1rem;
    border: 1px solid var(--border-color);
    border-radius: var(--border-radius);
    font-size: 1rem;
    transition: var(--transition);
    background: var(--card-bg);
}

.form-group input:focus,
.form-group textarea:focus,
.form-group select:focus {
    outline: none;
    border-color: var(--primary-color);
    box-shadow: 0 0 0 3px rgba(74, 144, 226, 0.1);
}

/* ====================================
   Buttons
   ==================================== */
.btn {
    display: inline-block;
    padding: 0.75rem 1.5rem;
    font-size: 1rem;
    font-weight: 500;
    text-align: center;
    text-decoration: none;
    border: none;
    border-radius: var(--border-radius);
    cursor: pointer;
    transition: var(--transition);
}

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

.btn-primary:hover {
    background-color: var(--primary-hover);
}

.btn-secondary {
    background-color: var(--secondary-color);
    color: white;
}

.btn-secondary:hover {
    background-color: #5a6268;
}

.btn-block {
    display: block;
    width: 100%;
}

.btn-sm {
    padding: 0.5rem 1rem;
    font-size: 0.9rem;
}

/* ====================================
   Alerts
   ==================================== */
.alert {
    padding: 1rem;
    border-radius: var(--border-radius);
    margin-bottom: 1.5rem;
}

.alert-error {
    background-color: #f8d7da;
    color: #721c24;
    border: 1px solid #f5c6cb;
}

.alert-success {
    background-color: #d4edda;
    color: #155724;
    border: 1px solid #c3e6cb;
}

.alert-warning {
    background-color: #fff3cd;
    color: #856404;
    border: 1px solid #ffeeba;
}

/* ====================================
   Utility Classes
   ==================================== */
.text-center {
    text-align: center;
}

.text-muted {
    color: var(--text-muted);
}

code {
    background: #f4f4f4;
    padding: 0.2rem 0.4rem;
    border-radius: 4px;
    font-family: "Courier New", monospace;
    font-size: 0.9em;
}

/* ====================================
   Responsive Design
   ==================================== */

/* Tablets */
@media (max-width: 768px) {
    .header-content {
        flex-direction: column;
        text-align: center;
    }

    .main-nav {
        flex-direction: column;
    }

    .welcome-section h2 {
        font-size: 1.5rem;
    }

    .tools-grid {
        grid-template-columns: repeat(auto-fill, minmax(200px, 1fr));
        gap: 1rem;
    }

    .tool-card {
        padding: 1.5rem 1rem;
    }

    .info-box {
        padding: 1.5rem;
    }
}

/* Mobile phones */
@media (max-width: 480px) {
    .container {
        padding: 0 15px;
    }

    .logo {
        font-size: 1.3rem;
    }

    .welcome-section h2 {
        font-size: 1.3rem;
    }

    .welcome-section p {
        font-size: 1rem;
    }

    .tools-grid {
        grid-template-columns: 1fr;
    }

    .tool-icon {
        font-size: 2.5rem;
    }

    .tool-name {
        font-size: 1.1rem;
    }

    .login-box {
        padding: 2rem 1.5rem;
    }

    .login-header h1 {
        font-size: 2rem;
    }

    .btn {
        padding: 0.7rem 1.2rem;
    }
}

/* Touch device optimizations */
@media (hover: none) {
    .tool-card:active {
        transform: scale(0.98);
    }

    .btn:active {
        transform: scale(0.98);
    }
}