:root {
    --bg-color: #f0f2f5;
    --card-bg: rgba(255, 255, 255, 0.7);
    --text-color: #333;
    --accent-color: #6366f1;
}

[data-theme='dark'] {
    --bg-color: #1f2937;
    --card-bg: rgba(31, 41, 55, 0.7);
    --text-color: #f9fafb;
    --accent-color: #818cf8;
}

body {
    background-color: var(--bg-color);
    color: var(--text-color);
    font-family: 'Segoe UI', sans-serif;
    margin: 0;
    padding: 20px;
    transition: background-color 0.3s, color 0.3s;
}

.app-container {
    max-width: 800px;
    margin: 0 auto;
}

header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    margin-bottom: 20px;
}

.reminder-form {
    background: var(--card-bg);
    backdrop-filter: blur(10px);
    padding: 20px;
    border-radius: 15px;
    display: flex;
    flex-direction: column;
    gap: 10px;
    margin-bottom: 20px;
}

.reminder-list {
    display: grid;
    gap: 15px;
}

.reminder-card {
    background: var(--card-bg);
    backdrop-filter: blur(10px);
    padding: 15px;
    border-radius: 10px;
    display: flex;
    justify-content: space-between;
    align-items: center;
}