/* Global Styles */
:root {
    /* Default theme colors (Light) */
    --color-primary: #667eea;
    --color-primary-dark: #5568d3;
    --color-secondary: #764ba2;
    --color-background: #ffffff;
    --color-surface: #f8f9fa;
    --color-text: #333333;
    --color-text-secondary: #666666;
    --color-border: #e0e0e0;
    --color-success: #11998e;
    --color-error: #ff6b6b;
    --gradient-header: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    --gradient-button-primary: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    --gradient-button-success: linear-gradient(135deg, #11998e 0%, #38ef7d 100%);
    
    /* Special effects for glassmorphism */
    --backdrop-filter: none;
    --border-glass: none;
    --box-shadow-glass: none;
}

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

body {
    font-family: 'Roboto', 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
    background: var(--gradient-header);
    min-height: 100vh;
    padding: 20px;
    color: var(--color-text);
    transition: background 0.3s ease, color 0.3s ease;
}

.container {
    max-width: 900px;
    margin: 0 auto;
    background: var(--color-background);
    border-radius: 20px;
    box-shadow: 0 20px 60px rgba(0, 0, 0, 0.3);
    overflow: hidden;
    backdrop-filter: var(--backdrop-filter);
    border: var(--border-glass);
}

/* Slide preview typography */
.slide-item {
    padding: 20px;
    min-height: 80px;
    margin-bottom: 16px;
    background: var(--color-surface);
    border: 1px solid var(--color-border);
    border-radius: 12px;
}
.slide-item h4 {
    font-family: 'Roboto', sans-serif;
    font-weight: 700;
    font-size: 42px;
    letter-spacing: 0.5px;
    margin-bottom: 8px;
}
.slide-item p {
    font-family: 'Roboto', sans-serif;
    font-weight: 400;
    font-size: 16px;
    line-height: 1.6;
    letter-spacing: 0px;
}
.slide-item p strong {
    font-weight: 700;
}

/* Header */
header {
    background: var(--gradient-header);
    color: var(--color-text);
    padding: 70px 30px 40px 30px;
    text-align: center;
    position: relative;
    backdrop-filter: var(--backdrop-filter);
    border-bottom: var(--border-glass);
}

/* Language Selector (LEFT) */
.language-selector {
    position: absolute;
    top: 20px;
    left: 30px;
    display: flex;
    align-items: center;
    gap: 10px;
    z-index: 10;
}

.language-selector label {
    font-size: 0.9em;
    font-weight: 500;
    color: var(--color-text);
    opacity: 0.9;
}

.language-dropdown {
    padding: 8px 12px;
    border: 2px solid var(--color-border);
    border-radius: 8px;
    background: var(--color-surface);
    color: var(--color-text);
    font-size: 0.95em;
    font-weight: 500;
    cursor: pointer;
    transition: all 0.3s;
    backdrop-filter: var(--backdrop-filter);
}

.language-dropdown:hover {
    background: var(--color-primary);
    border-color: var(--color-primary-dark);
    color: #ffffff;
}

.language-dropdown:focus {
    outline: none;
    background: var(--color-primary);
    border-color: var(--color-primary-dark);
    color: #ffffff;
}

.language-dropdown option {
    background: var(--color-background);
    color: var(--color-text);
    padding: 8px;
}

/* User Navigation (RIGHT) */
.user-nav {
    position: absolute;
    top: 20px;
    right: 30px;
    display: flex;
    align-items: center;
    gap: 10px;
    z-index: 10;
}

.nav-btn {
    color: white;
    text-decoration: none;
    font-weight: 500;
    padding: 8px 16px;
    background: rgba(255, 255, 255, 0.2);
    border-radius: 5px;
    transition: all 0.3s;
    white-space: nowrap;
    font-size: 0.95em;
}

.nav-btn:hover {
    background: rgba(255, 255, 255, 0.35);
    transform: translateY(-2px);
}

.nav-btn-signup {
    background: rgba(102, 126, 234, 0.9);
}

.nav-btn-signup:hover {
    background: rgba(102, 126, 234, 1);
}

.nav-btn-admin {
    background: rgba(255, 152, 0, 0.85);
}

.nav-btn-admin:hover {
    background: rgba(255, 152, 0, 1);
}

/* Theme Selector */
.theme-selector {
    position: absolute;
    top: 20px;
    left: 30px;
    display: flex;
    align-items: center;
    gap: 10px;
}

.theme-selector label {
    font-size: 1.2em;
}

.theme-dropdown {
    padding: 8px 12px;
    border: 2px solid var(--color-border);
    border-radius: 8px;
    background: var(--color-surface);
    color: var(--color-text);
    font-size: 0.95em;
    font-weight: 500;
    cursor: pointer;
    transition: all 0.3s;
    backdrop-filter: var(--backdrop-filter);
    width: 100%;
}

.theme-dropdown:hover {
    background: var(--color-primary);
    border-color: var(--color-primary-dark);
    color: #ffffff;
}

.theme-dropdown:focus {
    outline: none;
    background: var(--color-primary);
    border-color: var(--color-primary-dark);
    color: #ffffff;
}

.theme-dropdown option {
    background: var(--color-background);
    color: var(--color-text);
    padding: 8px;
}

/* Presentation Type Dropdown */
.type-dropdown {
    padding: 8px 12px;
    border: 2px solid var(--color-border);
    border-radius: 8px;
    background: var(--color-surface);
    color: var(--color-text);
    font-size: 0.95em;
    font-weight: 500;
    cursor: pointer;
    transition: all 0.3s;
    backdrop-filter: var(--backdrop-filter);
    width: 100%;
}

.type-dropdown:hover {
    background: var(--color-primary);
    border-color: var(--color-primary-dark);
    color: #ffffff;
}

.type-dropdown:focus {
    outline: none;
    background: var(--color-primary);
    border-color: var(--color-primary-dark);
    color: #ffffff;
}

.type-dropdown option {
    background: var(--color-background);
    color: var(--color-text);
    padding: 8px;
}

header h1 {
    font-size: 2.5em;
    margin-bottom: 10px;
}

.subtitle {
    font-size: 1.1em;
    opacity: 0.9;
}

/* Main Content */
main {
    padding: 40px 30px;
}

/* Form Section */
.form-section {
    max-width: 500px;
    margin: 0 auto;
}

.form-group {
    margin-bottom: 25px;
}

.form-group label {
    display: block;
    font-weight: 600;
    margin-bottom: 8px;
    color: var(--color-text);
    font-size: 1.05em;
}

.form-group input {
    width: 100%;
    padding: 12px 15px;
    border: 2px solid var(--color-border);
    border-radius: 8px;
    font-size: 1em;
    transition: border-color 0.3s;
    background: var(--color-surface);
    color: var(--color-text);
}

.form-group input:focus {
    outline: none;
    border-color: var(--color-primary);
}

.form-group small {
    display: block;
    margin-top: 5px;
    color: var(--color-text-secondary);
    font-size: 0.9em;
}

/* Buttons */
.btn-primary,
.btn-success,
.btn-secondary {
    width: 100%;
    padding: 15px 30px;
    border: none;
    border-radius: 10px;
    font-size: 1.1em;
    font-weight: 600;
    cursor: pointer;
    transition: all 0.3s;
    display: flex;
    align-items: center;
    justify-content: center;
    gap: 10px;
    color: white;
    text-decoration: none;
}

.btn-primary {
    background: var(--gradient-button-primary);
    color: white;
    margin-top: 10px;
}

.btn-primary:hover {
    transform: translateY(-2px);
    box-shadow: 0 10px 25px rgba(102, 126, 234, 0.4);
}

.btn-success {
    background: var(--gradient-button-success);
    color: white;
}

.btn-success:hover {
    transform: translateY(-2px);
    box-shadow: 0 10px 25px rgba(17, 153, 142, 0.4);
}

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

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

/* Loading Section */
.loading-section {
    text-align: center;
    padding: 40px 20px;
}

.spinner {
    width: 60px;
    height: 60px;
    border: 5px solid #f3f3f3;
    border-top: 5px solid #667eea;
    border-radius: 50%;
    margin: 0 auto 30px;
    animation: spin 1s linear infinite;
}

@keyframes spin {
    0% { transform: rotate(0deg); }
    100% { transform: rotate(360deg); }
}

.loading-section h2 {
    color: var(--color-text);
    margin-bottom: 10px;
}

.loading-text {
    color: var(--color-text-secondary);
    margin-bottom: 30px;
}

.progress-steps {
    display: flex;
    justify-content: center;
    gap: 30px;
    margin-top: 30px;
}

.step {
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: 10px;
    opacity: 0.3;
    transition: opacity 0.3s;
}

.step.active {
    opacity: 1;
}

.step-icon {
    font-size: 2em;
}

.step-text {
    font-size: 0.9em;
    color: var(--color-text-secondary);
}

/* Preview Section */
.preview-section {
    padding: 20px 0;
}

.preview-section h2 {
    text-align: center;
    color: var(--color-success);
    margin-bottom: 30px;
    font-size: 2em;
}

.preview-container {
    max-width: 700px;
    margin: 0 auto;
}

.preview-info {
    text-align: center;
    margin-bottom: 30px;
    padding: 20px;
    background: var(--color-surface);
    border-radius: 10px;
}

.preview-info h3 {
    color: var(--color-text);
    font-size: 1.8em;
    margin-bottom: 10px;
}

.preview-info p {
    color: var(--color-text-secondary);
    font-size: 1.1em;
}

.slides-preview {
    margin-bottom: 30px;
    max-height: 400px;
    overflow-y: auto;
    border: 2px solid var(--color-border);
    border-radius: 10px;
    padding: 20px;
    background: var(--color-surface);
}

.slide-item {
    background: var(--color-background);
    padding: 15px;
    margin-bottom: 15px;
    border-radius: 8px;
    border-left: 4px solid var(--color-primary);
    box-shadow: 0 2px 5px rgba(0, 0, 0, 0.05);
    overflow: hidden;
}

.slide-item h4 {
    color: var(--color-primary);
    margin-bottom: 10px;
    font-size: 1.2em;
    word-break: break-word;
    overflow-wrap: break-word;
    hyphens: auto;
}

.slide-item p {
    color: var(--color-text-secondary);
    line-height: 1.6;
    white-space: pre-line;
    word-break: break-word;
    overflow-wrap: break-word;
    hyphens: auto;
    max-height: 200px;
    overflow-y: auto;
}

.action-buttons {
    display: flex;
    gap: 15px;
}

.action-buttons button {
    flex: 1;
}

/* Error Section */
.error-section {
    text-align: center;
    padding: 40px 20px;
}

.error-container {
    max-width: 500px;
    margin: 0 auto;
    padding: 30px;
    background: var(--color-surface);
    border: 2px solid var(--color-error);
    border-radius: 10px;
}

.error-container h2 {
    color: var(--color-error);
    margin-bottom: 15px;
}

.error-container p {
    color: var(--color-text-secondary);
    margin-bottom: 20px;
    line-height: 1.6;
}

/* Footer */
footer {
    background: var(--color-surface);
    padding: 20px;
    text-align: center;
    color: var(--color-text-secondary);
    font-size: 0.9em;
}

/* Utility Classes */
.hidden {
    display: none !important;
}

/* Responsive Design */
@media (max-width: 768px) {
    body {
        padding: 10px;
    }
    
    header {
        padding: 120px 15px 30px 15px;
    }
    
    header h1 {
        font-size: 2em;
    }

    .subtitle {
        font-size: 1em;
    }
    
    /* Language selector responsive */
    .language-selector {
        top: 10px;
        left: 10px;
        flex-direction: column;
        gap: 5px;
        align-items: flex-start;
    }
    
    .language-selector label {
        font-size: 0.75em;
    }
    
    .language-dropdown {
        font-size: 0.85em;
        padding: 6px 10px;
    }
    
    /* User navigation responsive */
    .user-nav {
        top: 10px;
        right: 10px;
        flex-direction: column;
        gap: 6px;
        align-items: flex-end;
    }
    
    .nav-btn {
        font-size: 0.8em;
        padding: 6px 10px;
    }
    
    /* Theme selector responsive */
    .theme-selector {
        position: static;
        margin-bottom: 20px;
        justify-content: center;
    }
    
    .theme-selector label {
        font-size: 1em;
    }
    
    .theme-dropdown {
        font-size: 0.9em;
        padding: 6px 10px;
    }

    main {
        padding: 30px 20px;
    }

    .progress-steps {
        flex-direction: column;
        gap: 15px;
    }

    .action-buttons {
        flex-direction: column;
    }

    .slides-preview {
        max-height: 300px;
    }
}