/* Reset and Base Styles */
* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

:root {
    --bg-primary: #fafafa;
    --bg-secondary: white;
    --bg-tertiary: #f9f9f9;
    --text-primary: #2c3e50;
    --text-secondary: #7f8c8d;
    --text-tertiary: #555;
    --border-color: #e0e0e0;
    --border-light: #f0f0f0;
    --header-bg: linear-gradient(135deg, #FF6B6B 0%, #FF8E53 100%);
    --header-text: white;
    --primary-color: #FF6B6B;
    --primary-hover: #ff5252;
    --primary-gradient: linear-gradient(135deg, #FF6B6B 0%, #FF8E53 100%);
    --card-shadow: 0 2px 8px rgba(0,0,0,0.08);
    --card-shadow-hover: 0 4px 16px rgba(0,0,0,0.12);
    --success-bg: #E8F5E9;
    --success-text: #2E7D32;
    --success-border: #81C784;
    --error-bg: #FFEBEE;
    --error-text: #C62828;
    --error-border: #EF5350;
    --warning-bg: #FFF8E1;
    --overdue-bg: #FFEBEE;
    --never-bg: #FAFAFA;
    --modal-overlay: rgba(0,0,0,0.5);
}

body.dark-mode {
    --bg-primary: #1a1a1a;
    --bg-secondary: #2d2d2d;
    --bg-tertiary: #262626;
    --text-primary: #e0e0e0;
    --text-secondary: #b0b0b0;
    --text-tertiary: #c0c0c0;
    --border-color: #444;
    --border-light: #555;
    --header-bg: linear-gradient(135deg, #cc5555 0%, #d97656 100%);
    --header-text: #e0e0e0;
    --primary-color: #FF6B6B;
    --primary-hover: #ff5252;
    --primary-gradient: linear-gradient(135deg, #FF6B6B 0%, #FF8E53 100%);
    --card-shadow: 0 2px 8px rgba(0,0,0,0.4);
    --card-shadow-hover: 0 4px 16px rgba(0,0,0,0.6);
    --success-bg: #1b3d1b;
    --success-text: #81C784;
    --success-border: #2d5f2e;
    --error-bg: #3d1b1b;
    --error-text: #EF5350;
    --error-border: #5f2d2d;
    --warning-bg: #3d3a1b;
    --overdue-bg: #3d1b1b;
    --never-bg: #252525;
    --modal-overlay: rgba(0,0,0,0.8);
}

body {
    font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, Oxygen, Ubuntu, Cantarell, sans-serif;
    background: var(--bg-primary);
    color: var(--text-primary);
    line-height: 1.6;
    transition: background-color 0.3s, color 0.3s;
}

.container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 2rem 1.5rem;
}

.container h2 {
    font-size: 1.8rem;
    font-weight: 700;
    color: var(--text-primary);
    margin-bottom: 1rem;
    letter-spacing: -0.5px;
}

/* Screen Management */
.screen {
    min-height: 100vh;
}

/* Login Screen */
.login-box {
    background: var(--bg-secondary);
    border-radius: 20px;
    padding: 3rem 2.5rem;
    box-shadow: var(--card-shadow);
    max-width: 420px;
    margin: 15vh auto;
    text-align: center;
    border: 1px solid var(--border-light);
}

.login-box .logo {
    max-width: 280px;
    width: 100%;
    height: auto;
    margin-bottom: 1.5rem;
}

.login-box p {
    color: var(--text-secondary);
    margin-bottom: 2rem;
    font-size: 1.05rem;
}

.login-box form {
    margin-bottom: 0;
}

.login-box input[type="password"] {
    width: 100%;
    padding: 1rem 1.25rem;
    border: 2px solid var(--border-color);
    border-radius: 12px;
    font-size: 1.05rem;
    font-family: inherit;
    transition: all 0.3s;
    background: var(--bg-primary);
    color: var(--text-primary);
    margin-bottom: 1.25rem;
    box-shadow: inset 0 2px 4px rgba(0,0,0,0.05);
}

.login-box input[type="password"]:focus {
    outline: none;
    border-color: var(--primary-color);
    box-shadow: 0 0 0 4px rgba(255, 107, 107, 0.15), inset 0 2px 4px rgba(0,0,0,0.05);
    background: var(--bg-secondary);
}

.login-box input[type="password"]::placeholder {
    color: var(--text-secondary);
    opacity: 0.7;
}

.login-box button[type="submit"] {
    width: 100%;
    padding: 1rem;
    font-size: 1.05rem;
    margin-top: 0.5rem;
}

.login-box .error-message {
    margin-top: 1.5rem;
    margin-bottom: 0;
}

.login-box .error-message:empty {
    display: none;
    padding: 0;
    margin: 0;
}

/* Header */
.header {
    background: var(--header-bg);
    color: var(--header-text);
    padding: 1.25rem 1rem;
    box-shadow: 0 2px 12px rgba(0,0,0,0.1);
}

.header-content {
    max-width: 1200px;
    margin: 0 auto;
    display: flex;
    justify-content: space-between;
    align-items: center;
}

.header-logo {
    display: flex;
    align-items: center;
    gap: 0.875rem;
}

.header-logo .logo-icon {
    width: 42px;
    height: 42px;
    filter: drop-shadow(0 2px 4px rgba(0,0,0,0.1));
}

.header h1 {
    font-size: 1.6rem;
    margin: 0;
    font-weight: 600;
    letter-spacing: -0.5px;
}

.header-actions {
    display: flex;
    gap: 0.5rem;
    align-items: center;
}

.username {
    background: rgba(255,255,255,0.25);
    padding: 0.5rem 1rem;
    border-radius: 24px;
    font-size: 0.9rem;
    font-weight: 500;
    backdrop-filter: blur(10px);
}

/* Tabs Navigation */
.tabs {
    background: var(--bg-secondary);
    display: flex;
    border-bottom: 1px solid var(--border-light);
    padding: 0 1rem;
    overflow-x: auto;
    box-shadow: 0 1px 3px rgba(0,0,0,0.05);
}

.tab {
    background: none;
    border: none;
    padding: 1rem 1.5rem;
    cursor: pointer;
    font-size: 1rem;
    color: var(--text-secondary);
    border-bottom: 3px solid transparent;
    transition: all 0.3s;
    white-space: nowrap;
    font-weight: 500;
}

.tab:hover {
    color: var(--primary-color);
    background: rgba(255, 107, 107, 0.05);
}

.tab.active {
    color: var(--primary-color);
    border-bottom-color: var(--primary-color);
    font-weight: 600;
}

.tab-content {
    display: none;
    padding: 1rem 0;
}

.tab-content.active {
    display: block;
}

/* Dashboard */
.dashboard-grid {
    display: grid;
    gap: 1.25rem;
    margin-top: 1.5rem;
}

.dashboard-card {
    background: var(--bg-secondary);
    border-radius: 16px;
    padding: 1.75rem;
    box-shadow: var(--card-shadow);
    border-left: 5px solid var(--border-color);
    transition: all 0.3s ease;
    border: 1px solid var(--border-light);
}

.dashboard-card:hover {
    box-shadow: var(--card-shadow-hover);
    transform: translateY(-2px);
}

.dashboard-card.ok {
    border-left-color: var(--primary-color);
}

.dashboard-card.warning {
    border-left-color: #FF9800;
    background: var(--warning-bg);
}

.dashboard-card.overdue {
    border-left-color: #F44336;
    background: var(--overdue-bg);
}

.dashboard-card.never {
    border-left-color: #9E9E9E;
    background: var(--never-bg);
}

.dashboard-card h3 {
    margin-bottom: 0.75rem;
    font-size: 1.3rem;
    font-weight: 600;
    color: var(--text-primary);
}

.dashboard-card .status {
    font-size: 1.6rem;
    font-weight: 700;
    margin: 0.75rem 0;
    letter-spacing: -0.5px;
}

.dashboard-card .status.ok {
    color: #4CAF50;
}

.dashboard-card .status.warning {
    color: #FF9800;
}

.dashboard-card .status.overdue {
    color: #F44336;
}

.dashboard-card .info {
    font-size: 0.9rem;
    color: var(--text-secondary);
    margin-top: 0.5rem;
}

.dashboard-card .no-expiration {
    color: var(--text-secondary);
    font-style: italic;
}

.btn-record {
    margin-top: 1rem;
    width: 100%;
}

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

.form-group label {
    display: block;
    margin-bottom: 0.5rem;
    font-weight: 600;
    color: var(--text-tertiary);
}

.form-group input,
.form-group select,
.form-group textarea {
    width: 100%;
    padding: 0.875rem 1rem;
    border: 2px solid var(--border-color);
    border-radius: 10px;
    font-size: 1rem;
    font-family: inherit;
    transition: all 0.3s;
    background: var(--bg-secondary);
    color: var(--text-primary);
}

.form-group input:focus,
.form-group select:focus,
.form-group textarea:focus {
    outline: none;
    border-color: var(--primary-color);
    box-shadow: 0 0 0 3px rgba(255, 107, 107, 0.1);
}

/* Buttons */
.btn {
    padding: 0.875rem 1.75rem;
    border: none;
    border-radius: 12px;
    font-size: 1rem;
    cursor: pointer;
    transition: all 0.3s ease;
    font-weight: 600;
    box-shadow: 0 2px 4px rgba(0,0,0,0.1);
}

.btn:hover {
    transform: translateY(-1px);
    box-shadow: 0 4px 8px rgba(0,0,0,0.15);
}

.btn:active {
    transform: translateY(0);
}

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

.btn-primary:hover {
    opacity: 0.95;
}

.btn-small {
    padding: 0.5rem 1rem;
    font-size: 0.9rem;
    background: rgba(255,255,255,0.95);
    color: var(--primary-color);
    border-radius: 10px;
    font-weight: 600;
}

.btn-icon {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    padding: 0.5rem;
}

.btn-icon svg {
    display: block;
}

.btn-large {
    width: 100%;
    padding: 1rem;
    font-size: 1.1rem;
}

.btn-danger {
    background: #F44336;
    color: white;
}

.btn-danger:hover {
    background: #da190b;
}

/* History */
.history-list {
    margin-top: 1.5rem;
}

.history-item {
    background: var(--bg-secondary);
    border-radius: 14px;
    padding: 1.25rem;
    margin-bottom: 0.75rem;
    box-shadow: var(--card-shadow);
    display: flex;
    justify-content: space-between;
    align-items: center;
    border: 1px solid var(--border-light);
    transition: all 0.3s ease;
}

.history-item:hover {
    box-shadow: var(--card-shadow-hover);
    transform: translateX(4px);
}

.history-item .info {
    flex: 1;
}

.history-item .name {
    font-weight: 600;
    color: var(--text-primary);
}

.history-item .date {
    color: var(--text-secondary);
    font-size: 0.9rem;
}

.history-item .user {
    color: var(--primary-color);
    font-size: 0.85rem;
}

/* Messages */
.message,
.error-message {
    padding: 1rem;
    border-radius: 10px;
    margin-top: 1rem;
    font-size: 0.95rem;
    font-weight: 500;
}

.message {
    background: var(--success-bg);
    color: var(--success-text);
    border: 1px solid var(--success-border);
}

.error-message {
    background: var(--error-bg);
    color: var(--error-text);
    border: 1px solid var(--error-border);
}

.error-message:empty {
    display: none;
}

.loading {
    text-align: center;
    padding: 2rem;
    color: var(--text-secondary);
}

/* Modal */
.modal {
    display: none;
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background: var(--modal-overlay);
    z-index: 1000;
    overflow-y: auto;
}

.modal.active {
    display: flex;
    align-items: center;
    justify-content: center;
    padding: 1rem;
}

.modal-content {
    background: var(--bg-secondary);
    border-radius: 20px;
    width: 100%;
    max-width: 700px;
    box-shadow: 0 8px 32px rgba(0,0,0,0.2);
    max-height: 90vh;
    overflow-y: auto;
}

.modal-header {
    padding: 1.5rem;
    border-bottom: 1px solid var(--border-color);
    display: flex;
    justify-content: space-between;
    align-items: center;
}

.modal-header h2 {
    margin: 0;
    color: var(--text-primary);
}

.close-modal {
    background: none;
    border: none;
    font-size: 2rem;
    cursor: pointer;
    color: var(--text-secondary);
    line-height: 1;
    padding: 0;
}

.modal-body {
    padding: 1.5rem;
}

/* Admin Panel */
.admin-tabs {
    display: flex;
    gap: 0.5rem;
    margin-bottom: 1.5rem;
    border-bottom: 2px solid var(--border-color);
}

.admin-tab {
    background: none;
    border: none;
    padding: 0.75rem 1.5rem;
    cursor: pointer;
    font-size: 1rem;
    color: var(--text-secondary);
    border-bottom: 3px solid transparent;
    transition: all 0.3s;
    font-weight: 500;
}

.admin-tab:hover {
    color: var(--primary-color);
}

.admin-tab.active {
    color: var(--primary-color);
    border-bottom-color: #4CAF50;
    font-weight: 600;
}

.admin-tab-content {
    display: none;
}

.admin-tab-content.active {
    display: block;
}

.admin-list {
    margin-top: 1rem;
}

.admin-item {
    background: var(--bg-tertiary);
    border: 1px solid var(--border-color);
    border-radius: 6px;
    padding: 1rem;
    margin-bottom: 0.5rem;
    display: flex;
    justify-content: space-between;
    align-items: center;
}

.admin-item .item-info {
    flex: 1;
}

.admin-item .item-actions {
    display: flex;
    gap: 0.5rem;
}

.form-actions {
    display: flex;
    gap: 1rem;
    margin-top: 1.5rem;
}

.form-actions button {
    flex: 1;
}

.cancel-modal {
    background: #9E9E9E;
    color: white;
}

/* Notification Settings */
.notification-status {
    padding: 1rem;
    background: var(--bg-tertiary);
    border-radius: 6px;
    margin-bottom: 1rem;
}

.notification-actions {
    display: flex;
    gap: 0.5rem;
    margin-bottom: 1rem;
}

.notification-info {
    margin-top: 1rem;
    padding: 1rem;
    background: var(--bg-tertiary);
    border-radius: 6px;
    font-size: 0.9rem;
}

/* Responsive Design */
@media (max-width: 600px) {
    .login-box .logo {
        max-width: 240px;
    }
    
    .header-content {
        flex-direction: column;
        gap: 0.5rem;
        text-align: center;
    }
    
    .header-logo {
        justify-content: center;
    }
    
    .tabs {
        padding: 0;
    }
    
    .tab {
        padding: 0.75rem 1rem;
        font-size: 0.9rem;
    }
    
    .dashboard-grid {
        gap: 0.9rem;
    }
    
    .dashboard-card {
        padding: 1rem;
        border-radius: 12px;
    }
    
    .dashboard-card h3 {
        font-size: 1.1rem;
        margin-bottom: 0.5rem;
    }
    
    .dashboard-card .status {
        font-size: 1.3rem;
        margin: 0.5rem 0;
    }
    
    .dashboard-card .info {
        font-size: 0.85rem;
        margin-top: 0.4rem;
    }
    
    .history-item {
        flex-direction: column;
        align-items: flex-start;
        gap: 0.5rem;
    }
    
    .form-actions {
        flex-direction: column;
    }
}