/* ==========================================================================
   1. Reset & Global Styles
   ========================================================================== */
:root {
    --primary-color: #4f46e5;
    --primary-hover: #4338ca;
    --background: #f8fafc;
    --card-bg: #ffffff;
    --text-main: #0f172a;
    --text-muted: #64748b;
    --border-color: #e2e8f0;
    --danger-color: #ef4444;
    --danger-hover: #dc2626;
    --success-color: #10b981;
    --radius: 12px;
    --shadow: 0 10px 15px -3px rgba(0, 0, 0, 0.05), 0 4px 6px -4px rgba(0, 0, 0, 0.05);
}

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

body {
    font-family: 'Inter', sans-serif;
    background-color: var(--background);
    color: var(--text-main);
    display: flex;
    justify-content: center;
    align-items: center;
    min-height: 100vh;
    padding: 20px;
}

/* ==========================================================================
   2. Layout Container
   ========================================================================== */
.todo-card {
    background: var(--card-bg);
    width: 100%;
    max-width: 650px;
    border-radius: var(--radius);
    box-shadow: var(--shadow);
    padding: 30px;
}

header {
    margin-bottom: 25px;
    display: flex;
    justify-content: space-between;
    align-items: center;
}

header h1 {
    font-size: 1.5rem;
    font-weight: 700;
    color: var(--text-main);
    display: flex;
    align-items: center;
    gap: 10px;
}

header h1 i {
    color: var(--primary-color);
}

/* ==========================================================================
   3. Input Form Elements
   ========================================================================== */
.input-container {
    display: flex;
    flex-direction: column;
    gap: 16px;
    background: #f1f5f9;
    padding: 20px;
    border-radius: var(--radius);
    margin-bottom: 30px;
}

.input-group {
    display: flex;
    flex-direction: column;
    gap: 6px;
}

.input-group label {
    font-size: 0.75rem;
    font-weight: 600;
    color: var(--text-muted);
    text-transform: uppercase;
    letter-spacing: 0.5px;
}

/* Common input styling */
input[type="text"],
input[type="date"],
input[type="time"] {
    width: 100%;
    padding: 12px 16px;
    font-family: inherit;
    font-size: 0.95rem;
    border: 1px solid var(--border-color);
    border-radius: 8px;
    background-color: #ffffff;
    color: var(--text-main);
    transition: all 0.2s ease;
}

input[type="text"]:focus,
input[type="date"]:focus,
input[type="time"]:focus {
    outline: none;
    border-color: var(--primary-color);
    box-shadow: 0 0 0 3px rgba(79, 70, 229, 0.15);
}

/* Date and Time alignment side by side */
.datetime-group {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 12px;
}

/* Action Button */
#addTaskBtn {
    background-color: var(--primary-color);
    color: #ffffff;
    border: none;
    padding: 14px;
    font-size: 0.95rem;
    font-weight: 600;
    border-radius: 8px;
    cursor: pointer;
    display: flex;
    justify-content: center;
    align-items: center;
    gap: 8px;
    transition: background-color 0.2s ease, transform 0.1s ease;
}

#addTaskBtn:hover {
    background-color: var(--primary-hover);
}

#addTaskBtn:active {
    transform: scale(0.98);
}

/* Messages */
.span {
    font-size: 0.85rem;
    color: var(--danger-color);
}

.info-message {
    font-size: 0.85rem;
    color: var(--success-color);
    font-weight: 500;
}

/* ==========================================================================
   4. Tasks Table View
   ========================================================================== */
.table-responsive {
    width: 100%;
    overflow-x: auto;
}

table {
    width: 100%;
    border-collapse: collapse;
    text-align: left;
}

th {
    padding: 12px 16px;
    font-size: 0.8rem;
    font-weight: 600;
    text-transform: uppercase;
    letter-spacing: 0.5px;
    color: var(--text-muted);
    border-bottom: 2px solid var(--border-color);
}

td {
    padding: 16px;
    border-bottom: 1px solid var(--border-color);
    vertical-align: middle;
    font-size: 0.95rem;
}

tr:last-child td {
    border-bottom: none;
}

/* Custom Checkbox Design */
.task-checkbox {
    width: 18px;
    height: 18px;
    accent-color: var(--success-color);
    cursor: pointer;
}

/* Text styles inside table */
.task-text {
    font-weight: 500;
    color: var(--text-main);
}

/* Deadline badge style */
.deadline-badge {
    background-color: #f1f5f9;
    color: var(--text-muted);
    padding: 4px 8px;
    border-radius: 6px;
    font-size: 0.8rem;
    font-weight: 500;
    display: inline-block;
}

/* Table Delete Button */
.btn-delete {
    background: none;
    border: none;
    color: var(--text-muted);
    font-size: 1.1rem;
    cursor: pointer;
    padding: 6px;
    border-radius: 6px;
    transition: all 0.2s ease;
}

.btn-delete:hover {
    color: var(--danger-color);
    background-color: #fef2f2;
}

/* Styling changes for dynamically finished tasks (Add via JavaScript classList toggle if you wish) */
.completed-task {
    text-decoration: line-through;
    color: var(--text-muted);
    opacity: 0.6;
}