:root {
    --bg-color: #f8f9fa;
    --card-bg: #ffffff;
    --border-color: #e5e7eb;
    --text-main: #111827;
    --text-muted: #6b7280;
    --primary-blue: #3b82f6; 
    --primary-blue-light: #eff6ff;
    --primary-orange: #f59e0b;
    --input-bg: #f9fafb;
    --shadow-sm: 0 1px 3px 0 rgba(0, 0, 0, 0.05);
}

* { box-sizing: border-box; margin: 0; padding: 0; font-family: 'Inter', sans-serif; }

body {
    background-color: var(--bg-color);
    color: var(--text-main);
    display: flex;
    justify-content: center;
    min-height: 100vh;
    padding: 24px 16px;
    transition: background-color 0.3s, color 0.3s;
}

.app-container { width: 100%; max-width: 600px; display: flex; flex-direction: column; gap: 16px; }

/* Card Base */
.app-card {
    background: var(--card-bg);
    border: 1px solid var(--border-color);
    border-radius: 16px;
    padding: 20px;
    box-shadow: var(--shadow-sm);
    transition: background-color 0.3s, border-color 0.3s;
}

/* Header Panel */
.header-panel { padding: 20px; display: flex; justify-content: space-between; align-items: center; }
.brand { display: flex; align-items: center; gap: 16px; cursor: pointer; user-select: none; }
.logo-icon { font-size: 20px; background: var(--primary-blue); width: 46px; height: 46px; display: flex; align-items: center; justify-content: center; border-radius: 14px; color: white; transition: background-color 0.3s; }
.brand-text h1 { font-size: 1.25rem; font-weight: 700; color: var(--text-main); letter-spacing: -0.5px; }
.streak { font-size: 0.85rem; color: var(--primary-orange); font-weight: 600; display: block; margin-top: 2px; }
.btn-install { background: #10b981; color: white; border: none; padding: 10px 14px; border-radius: 10px; font-size: 0.8rem; font-weight: 600; cursor: pointer; transition: background 0.2s; white-space: nowrap; }
.btn-install:hover { background: #059669; }

/* Navigation Panel */
.nav-panel { display: flex; flex-direction: column; gap: 10px; }
.nav-btn {
    background: var(--card-bg); border: 1px solid var(--border-color);
    color: var(--text-muted); padding: 16px 20px; border-radius: 14px;
    cursor: pointer; font-weight: 500; font-size: 0.95rem;
    text-align: left; display: flex; align-items: center; gap: 12px;
    transition: all 0.2s ease;
}
.nav-btn:hover { background: var(--input-bg); color: var(--text-main); }
.nav-btn.active { background: var(--primary-blue-light); border-color: var(--primary-blue); color: var(--primary-blue); font-weight: 500; }
.nav-icon { font-size: 1.1rem; }
.nav-text { flex: 1; }
.lock-icon { margin-left: auto; font-size: 0.8rem; opacity: 0.7; }

/* Theme Panel */
.theme-panel { padding: 20px; }
.panel-header { font-size: 0.75rem; font-weight: 700; color: var(--primary-blue); margin-bottom: 12px; display: flex; align-items: center; gap: 6px; letter-spacing: 0.5px; transition: color 0.3s; }
.custom-select-wrapper { position: relative; user-select: none; }
.custom-select-trigger {
    display: flex; justify-content: space-between; align-items: center;
    background: var(--input-bg); border: 1px solid var(--border-color);
    padding: 16px 20px; border-radius: 12px; cursor: pointer;
    font-size: 0.95rem; color: var(--text-main); font-weight: 500;
    transition: border-color 0.2s;
}
.custom-select-trigger:hover { border-color: var(--primary-blue); }
.custom-select-trigger .arrow { font-size: 0.7rem; transition: transform 0.2s; color: var(--text-muted); }
.custom-select-wrapper.open .arrow { transform: rotate(180deg); }
.custom-options {
    position: absolute; top: 100%; left: 0; right: 0;
    background: var(--card-bg); border: 1px solid var(--border-color);
    border-radius: 12px; margin-top: 8px; z-index: 100;
    max-height: 250px; overflow-y: auto;
    display: none; flex-direction: column;
    box-shadow: 0 10px 25px -5px rgba(0, 0, 0, 0.1);
}
.custom-options::-webkit-scrollbar { width: 8px; }
.custom-options::-webkit-scrollbar-track { background: var(--input-bg); border-radius: 4px; }
.custom-options::-webkit-scrollbar-thumb { background: #cbd5e1; border-radius: 4px; }

.custom-select-wrapper.open .custom-options { display: flex; }
.custom-option {
    padding: 14px 20px; cursor: pointer; font-size: 0.9rem;
    color: var(--text-main); border-bottom: 1px solid var(--border-color);
    transition: background 0.2s, color 0.2s;
}
.custom-option:last-child { border-bottom: none; }
.custom-option:hover { background: var(--primary-blue-light); color: var(--primary-blue); }
.custom-option.selected { background: var(--primary-blue-light); color: var(--primary-blue); font-weight: 600; }

/* Pro Panel */
.pro-panel { padding: 20px; display: flex; flex-direction: column; gap: 10px; }
.pro-header { display: flex; align-items: center; gap: 16px; margin-bottom: 6px; }
.crown { font-size: 1.8rem; line-height: 1; }
.pro-text h3 { font-size: 1.05rem; font-weight: 700; color: var(--text-main); }
.pro-text p { font-size: 0.85rem; color: var(--text-muted); margin-top: 2px; }
.btn-pro {
    width: 100%; padding: 16px; background: var(--primary-orange);
    border: none; border-radius: 12px; color: white; font-weight: 600; font-size: 0.95rem;
    cursor: pointer; transition: all 0.2s;
}
.btn-pro:hover { filter: brightness(0.95); transform: translateY(-1px); }
.btn-logout { width: 100%; padding: 14px; background: #ef4444; border: none; border-radius: 12px; color: white; font-weight: 600; font-size: 0.95rem; cursor: pointer; }
.btn-logout:hover { filter: brightness(0.9); }
.btn-export { width: 100%; padding: 14px; background: #10b981; border: none; border-radius: 12px; color: white; font-weight: 600; font-size: 0.95rem; cursor: pointer; }
.btn-exit-admin { width: 100%; padding: 14px; background: #ef4444; border: none; border-radius: 12px; color: white; font-weight: 600; font-size: 0.95rem; cursor: pointer; }
.btn-exit-admin:hover { filter: brightness(0.9); }

/* Task Panel */
.task-panel { padding: 20px; }
.task-header { display: flex; justify-content: space-between; align-items: flex-start; margin-bottom: 20px; }
.task-header h2 { font-size: 1.1rem; font-weight: 700; color: var(--text-main); }
.task-header p { font-size: 0.85rem; color: var(--text-muted); margin-top: 4px; }

.search-input { width: 100%; padding: 16px; background: var(--input-bg); border: 1px solid var(--border-color); border-radius: 12px; color: var(--text-main); outline: none; font-size: 0.9rem; margin-bottom: 12px; transition: border-color 0.2s; }
.search-input:focus { border-color: var(--primary-blue); }
.search-input::placeholder { color: var(--text-muted); }

.input-group { display: flex; gap: 12px; margin-bottom: 16px; }
.task-input { flex: 1; padding: 16px; background: var(--input-bg); border: 1px solid var(--border-color); border-radius: 12px; color: var(--text-main); outline: none; font-size: 0.9rem; transition: border-color 0.2s; }
.task-input:focus { border-color: var(--primary-blue); }
.task-input::placeholder { color: var(--text-muted); }
.btn-add { padding: 0 24px; background: var(--primary-blue); border: none; border-radius: 12px; color: white; font-weight: 600; cursor: pointer; font-size: 0.9rem; transition: all 0.2s; }
.btn-add:hover { filter: brightness(0.9); transform: translateY(-1px); }

.filters { display: flex; gap: 8px; margin-bottom: 20px; }
.filter-btn { padding: 10px 18px; background: var(--input-bg); border: 1px solid transparent; border-radius: 10px; color: var(--text-muted); font-size: 0.85rem; font-weight: 500; cursor: pointer; transition: all 0.2s; }
.filter-btn:hover { background: var(--primary-blue-light); color: var(--primary-blue); }
.filter-btn.active { background: var(--primary-blue); color: white; }

/* Task List */
.task-list { list-style: none; display: flex; flex-direction: column; gap: 10px; }
.task-item { background: var(--card-bg); border: 1px solid var(--border-color); border-radius: 12px; padding: 16px; display: flex; align-items: flex-start; gap: 12px; transition: border-color 0.2s, box-shadow 0.2s; }
.task-item:hover { border-color: var(--primary-blue-light); box-shadow: 0 2px 8px rgba(0,0,0,0.04); }
.task-checkbox { appearance: none; width: 22px; height: 22px; border: 2px solid var(--border-color); border-radius: 6px; cursor: pointer; position: relative; margin-top: 2px; flex-shrink: 0; transition: all 0.2s; }
.task-checkbox:hover { border-color: var(--primary-blue); }
.task-checkbox:checked { background: var(--primary-blue); border-color: var(--primary-blue); }
.task-checkbox:checked::after { content: '✓'; position: absolute; top: 50%; left: 50%; transform: translate(-50%, -50%); color: white; font-size: 12px; font-weight: bold; }
.task-content { flex: 1; display: flex; flex-direction: column; gap: 6px; }
.task-text { font-size: 0.95rem; font-weight: 500; color: var(--text-main); }
.task-text.completed { text-decoration: line-through; color: var(--text-muted); }
.task-meta { font-size: 0.75rem; color: var(--text-muted); display: flex; align-items: center; gap: 4px; }
.delete-btn { background: transparent; border: none; color: #ef4444; cursor: pointer; font-size: 1rem; opacity: 0.4; transition: opacity 0.2s; }
.delete-btn:hover { opacity: 1; }

/* Views */
.view { display: none; animation: fadeIn 0.2s ease; }
.view.active { display: block; }
@keyframes fadeIn { from { opacity: 0; transform: translateY(5px); } to { opacity: 1; transform: translateY(0); } }

/* Calendar */
.calendar-container { background: var(--input-bg); border-radius: 12px; padding: 16px; margin-bottom: 16px; }
.calendar-header { display: flex; justify-content: space-between; align-items: center; margin-bottom: 16px; }
.calendar-header h3 { font-size: 1rem; font-weight: 700; color: var(--text-main); }
.cal-nav { background: var(--card-bg); border: 1px solid var(--border-color); border-radius: 8px; width: 36px; height: 36px; display: flex; align-items: center; justify-content: center; cursor: pointer; color: var(--text-main); transition: all 0.2s; }
.cal-nav:hover { background: var(--primary-blue-light); color: var(--primary-blue); border-color: var(--primary-blue); }
.calendar-weekdays { display: grid; grid-template-columns: repeat(7, 1fr); text-align: center; font-size: 0.75rem; font-weight: 600; color: var(--text-muted); margin-bottom: 8px; }
.calendar-grid { display: grid; grid-template-columns: repeat(7, 1fr); gap: 4px; }
.calendar-day { background: var(--card-bg); aspect-ratio: 1; display: flex; align-items: center; justify-content: center; border-radius: 8px; font-size: 0.85rem; font-weight: 500; cursor: pointer; border: 1px solid transparent; color: var(--text-main); transition: all 0.2s ease; }
.calendar-day:hover { background: var(--primary-blue-light); color: var(--primary-blue); border-color: var(--primary-blue); transform: scale(1.05); }
.calendar-day.today { border-color: var(--primary-blue); color: var(--primary-blue); font-weight: 700; }
.calendar-day.locked { opacity: 0.5; cursor: not-allowed; }
.calendar-day.locked:hover { background: var(--card-bg); color: var(--text-main); transform: none; border-color: transparent; }
.calendar-day.selected { background: var(--primary-blue); color: white; border-color: var(--primary-blue); }
.selected-date-display { background: var(--input-bg); border: 1px solid var(--border-color); border-radius: 12px; padding: 16px; font-size: 0.9rem; font-weight: 500; color: var(--text-main); }

/* History */
.btn-clear { background: #ef4444; color: white; border: none; padding: 8px 16px; border-radius: 8px; font-size: 0.8rem; font-weight: 600; cursor: pointer; display: flex; align-items: center; gap: 6px; transition: background 0.2s; }
.btn-clear:hover { filter: brightness(0.9); }

/* Footer */
.footer { text-align: center; font-size: 0.8rem; color: var(--text-muted); padding: 20px 0; }

/* Utility class to enforce hiding */
.hidden { display: none !important; }

/* Modals */
.modal-overlay { position: fixed; top: 0; left: 0; right: 0; bottom: 0; background: rgba(0, 0, 0, 0.4); backdrop-filter: blur(4px); display: flex; align-items: center; justify-content: center; z-index: 1000; opacity: 0; pointer-events: none; transition: opacity 0.3s; }
.modal-overlay.active { opacity: 1; pointer-events: auto; }
.modal-content { width: 90%; max-width: 400px; text-align: center; padding: 24px; background: var(--card-bg); border-radius: 20px; border: 1px solid var(--border-color); }
.pro-modal-content { text-align: left; }
.modal-header { display: flex; justify-content: space-between; align-items: center; margin-bottom: 16px; }
.modal-header h2 { font-size: 1.2rem; color: var(--text-main); }
.close-modal { background: transparent; border: none; color: var(--text-muted); font-size: 1.5rem; cursor: pointer; }
.modal-desc { font-size: 0.9rem; color: var(--text-muted); line-height: 1.5; margin-bottom: 20px; }

/* Device ID Box */
.device-id-box { background: var(--input-bg); border: 1px solid var(--border-color); border-radius: 12px; padding: 12px; margin-bottom: 16px; text-align: center; }
.device-id-box p { font-size: 0.75rem; font-weight: 700; color: var(--text-muted); letter-spacing: 1px; margin-bottom: 8px; }
.device-id-row { display: flex; justify-content: center; align-items: center; gap: 10px; }
.device-id-row span { font-size: 1.1rem; font-family: monospace; font-weight: 700; color: var(--text-main); }
#copy-device-id-btn { background: transparent; border: none; cursor: pointer; font-size: 1rem; opacity: 0.7; transition: opacity 0.2s; }
#copy-device-id-btn:hover { opacity: 1; }

/* Instagram Button */
.btn-instagram { 
    display: flex; align-items: center; justify-content: center;
    width: 100%; padding: 14px; background: #d6336c; color: white; 
    text-decoration: none; border-radius: 12px; font-weight: 600; 
    text-align: center; margin-bottom: 20px; font-size: 0.9rem; 
    transition: background 0.2s, transform 0.2s; 
}
.btn-instagram:hover { background: #b02a56; transform: translateY(-1px); }

/* Promo Input */
.promo-label { font-size: 0.75rem; font-weight: 700; color: var(--text-muted); text-align: center; margin-bottom: 10px; letter-spacing: 0.5px; }
.promo-row { display: flex; gap: 10px; }
.promo-row input { flex: 1; padding: 14px; background: var(--input-bg); border: 1px solid var(--border-color); border-radius: 12px; color: var(--text-main); outline: none; font-size: 0.9rem; transition: border-color 0.2s; }
.promo-row input:focus { border-color: var(--primary-blue); }
.btn-activate { padding: 0 20px; background: var(--primary-blue); border: none; border-radius: 12px; color: white; font-weight: 600; cursor: pointer; transition: filter 0.2s; }
.btn-activate:hover { filter: brightness(0.9); }

/* Modal Actions */
.modal-actions { display: flex; gap: 10px; margin-top: 16px; }
.btn-cancel, .btn-submit, .btn-danger { flex: 1; padding: 14px; border: none; border-radius: 12px; cursor: pointer; font-weight: 600; font-size: 0.95rem; }
.btn-cancel { background: var(--input-bg); color: var(--text-main); border: 1px solid var(--border-color); }
.btn-submit { background: var(--primary-blue); color: white; }
.btn-danger { background: #ef4444; color: white; }
.error-msg { color: #ef4444; font-size: 0.85rem; margin-top: 12px; min-height: 1rem; text-align: center; font-weight: 500; }

/* --- TOAST NOTIFICATION --- */
.toast-container {
    position: fixed;
    top: 24px;
    left: 50%;
    transform: translateX(-50%);
    display: flex;
    flex-direction: column;
    gap: 10px;
    z-index: 9999;
    pointer-events: none;
}

.toast {
    background: var(--card-bg);
    color: var(--text-main);
    border: 2px solid var(--primary-blue);
    padding: 16px 24px;
    border-radius: 16px;
    box-shadow: 0 10px 30px rgba(0, 0, 0, 0.15);
    display: flex;
    align-items: center;
    gap: 12px;
    font-weight: 500;
    font-size: 0.95rem;
    min-width: 300px;
    
    transform: translateY(-100px);
    opacity: 0;
    animation: slideDown 0.4s cubic-bezier(0.175, 0.885, 0.32, 1.275) forwards;
}

.toast.hiding {
    animation: fadeOutUp 0.3s ease forwards;
}

.toast-icon {
    font-size: 1.3rem;
}

@keyframes slideDown {
    to { transform: translateY(0); opacity: 1; }
}

@keyframes fadeOutUp {
    to { transform: translateY(-50px); opacity: 0; }
}